Die Autoren haben keine Anerkennung.

1. Vorläuferlösung Vorbereitung HINWEIS: Bitte konsultieren Sie vor dem Gebrauch alle relevanten Sicherheitsdatenblätter (MSDS). Mehrere der in diesem Verfahren verwendeten Chemikalien sind schädlich und / oder giftig für den Menschen. Nanomaterialien können zusätzliche Gefahren im Vergleich zu ihrem Bulk-Gegenstück haben. Bitte die entsprechenden Sicherheitsmaßnahmen und persönliche Schutzausrüstung verwenden. <ol><li> 5 g Titan (IV) n-butoxid, 1 g Polyvinylpyrrolidon (PVP), 1 ml Eisessig und 10 ml absolutem Ethanol in ein Probengefäß geben. </li><li> Verwenden Sie eine magnetische Rührplatte, um die Lösung zu mischen, bis sie homogen geworden ist und keine Blasen beobachtet werden können. </li></ol> 2. Elektrospinnen und Kalzinieren der Nanofasern <ol><li> Die Nadel, die für den Elektrospinnvorgang verwendet wird, vorbereiten, indem man die Spitze einer 21 G-Nadel abschneidet und mit mäßigem Sandpapier abschleift, bis die Spitze vollständig flach ist. </li><li> Montieren Sie die NotwendigkeitLe auf eine Einweg-10-ml-Spritze. </li><li> Legen Sie einige der Vorläuferlösung in die Spritze und legen Sie sie auf die Spritzenpumpe. </li><li> Wickeln Sie die Kollektorplatte in Aluminiumfolie ein und legen Sie sie direkt vor die Nadelspitze. HINWEIS: Der Abstand von der Nadel zur Platte sollte 20 cm betragen. </li><li> Verbinden Sie die Kollektorplatte mit dem Boden und der Nadel mit der Hochspannungsquelle. </li><li> Legen Sie den Schutzschild um das Setup herum. </li><li> Stellen Sie den Durchfluss auf die Spritzenpumpe auf 1 mL / h ein und beginnen Sie zu pumpen. </li><li> Sobald eine Lösung an der Spitze der Nadel erscheint, schalten Sie die Hochspannungsquelle ein und stellen Sie sie auf 15 kV ein. HINWEIS: An diesem Punkt werden Fasern auf dem Teller sammeln. Der Aufbau wird so lange wie nötig gelassen, um die gewünschte Dicke der Fasermatte zu erreichen. </li><li> Nachdem das Spinnen beendet ist, schalten Sie die Hochspannungsquelle und die Spritzenpumpe aus. Entfernen Sie die Folie von der Kollektorplatte. </li><li> Lassen Sie die Fasern ruhen oVernichten und dann die Aluminiumfolie abziehen. </li><li> Legen Sie die abgezogenen Fasern in einen Tiegel und legen Sie sie in einen Muffelofen. </li><li> Kalzinieren der Fasern durch Aufstellen einer Temperaturrampe von 5 ° / min bis 500 ° C und Halten für 2 h zur Entfernung des PVP und zur Herstellung von reinen TiO 2 -Nanofasern. </li><li> Sobald der Kalzinierungsvorgang abgeschlossen ist, lassen Sie den Ofen geschlossen, bis die Temperatur unter 80 ° C reicht, um einen thermischen Schock zu vermeiden, der die Fasern beschädigen könnte. </li></ol> 3. Elektrodenfertigung <ol><li> Vorbereitung der Aufschlämmungen <ol><li> Fügen Sie 500 mg Titandioxid-Paste zu 20 ml Ethanol in einem Rundkolben hinzu. </li><li> In einem separaten Kolben werden 500 mg der elektrogesponnenen TiO 2 -NFs mit weiteren 20 ml Ethanol vermischt. </li><li> Sonate die Lösungen für 2 h mit einem Bad-Sonicator. </li><li> Sobald einheitliche Mischungen erhalten werden, fügen Sie 2 ml Terpineol zu jedem Kolben und Sonate für einAndere 15 min. </li><li> Verdampfe das Lösungsmittel aus beiden Kolben unter Verwendung eines Rotationsverdampfers, um die Aufschlämmungen zu erhalten. </li></ol></li><li> Doktor Blading und Sinterung <ol><li> Mit einem Diamant-Glasschneider einen FTO-leitfähigen Glasschieber in ein 2 cm x 2 cm großes Quadrat schneiden. </li><li> Sichern Sie den FTO-Schieber in den Arbeitsbereich, indem Sie Klebeband auf den Glasschieber legen, so dass ein 0.4-cm 2- Bereich in der Mitte freigelegt wird. Um eine unregelmäßige Beschichtung zu vermeiden, platziere das Band auf zwei parallelen Seiten und dann auf die beiden anderen. </li><li> Legen Sie ein paar Tropfen der TiO 2 -NP-Aufschlämmung auf die exponierte Mitte des Objektträgers auf. </li><li> Verwenden Sie eine Rasierklinge, um die Aufschlämmung gleichmäßig über den exponierten Bereich zu verteilen. </li><li> Sobald eine gleichmäßige Beschichtung erreicht ist, entfernen Sie vorsichtig das Klebeband. </li><li> Den beschichteten Schieber in einen Ofen geben und 2 h bei 500 ° C sintern. </li><li> Wiederholen Sie die Schritte 3.2.2-3.2.6 auf der gleichen FTO-Folie, diesmal mit der TiO 2 -NF-Aufschlämmung anstelle vonDie Nanopartikel, um die Photoanode zu erhalten. </li></ol></li></ol> 4. NF Charakterisierung <ol><li> SEM-Charakterisierung <ol><li> Bereiten Sie die Probe für SEM vor, indem Sie einen Streifen Klebstoff-Klebeband an einen Mikroskopstutzen anschließen. Setzen Sie sorgfältig eine kleine Menge Nanofasern auf das Band. </li><li> Montieren Sie den Stutzen auf einen Probenhalter und legen Sie ihn in die Austauschkammer des Gerätes. </li><li> Stellen Sie die Gerätebedingungen und Parameter ein: Stellen Sie die Beschleunigungsspannung auf 20 kV und den Arbeitsabstand auf 10 mm ein. </li><li> Sammeln Sie Bilder der Probe, um sicherzustellen, dass sie die Gesamtmorphologie des Materials anzeigen. </li></ol></li><li> XRD-Charakterisierung <ol><li> Schütteln Sie einige Nanofasern vorsichtig in ein feines Pulver und breiten sie gleichmäßig auf einer XRD-Stufe aus. </li><li> Legen Sie die Probe in das Diffraktometer ein. </li><li> Stellen Sie die Erfassungsparameter ein: Verwenden Sie einen Startwinkel von 10 °, einen Endwinkel von 80 °, einDa Schrittgröße von 0,015 °. </li><li> Starten Sie die Erfassung der XRD-Daten. </li></ol></li></ol> 5. Solarzellenfertigung <ol><li> Die Photoanode mit einer wässrigen Lösung von TiCl &amp; sub4; bei 75ºC für 45 min behandeln. Nach der Behandlung mit gewaschenem Wasser waschen und trocknen lassen. </li><li> Sensibilisieren Sie die Photoanode, indem Sie sie in einer 0,5 mM Lösung des Rutheniumfarbstoffs N719 in absolutem Ethanol für 24 h unter dunklen Bedingungen eintauchen. </li><li> Legen Sie eine Folie des Siegelfilms auf die sensibilisierte Photoanode, um als thermoplastische Dichtung zwischen dem Photoanode und der Gegenelektrode zu dienen. </li><li> Legen Sie eine Pt-beschichtete FTO-Gegenelektrode mit einem vorgebohrten Loch in der Mitte auf die Oberseite der Siegelfolie, so dass beide Seiten einander zugewandt sind. </li><li> Die zusammengesetzte Zelle 15 min lang auf 100 ° C erhitzen, um die Dichtung abzudichten. </li><li> Ein paar Tropfen eines Redoxmediators, bestehend aus einer Lösung von 1-Propyl-3-methylimidazoliumjodid (0,8 M), Iod (0,1 M),Und Benzimidazol (0,3 M) in 3-Methoxypropionitril, oben auf dem vorgebohrten Loch der Gegenelektrode. </li><li> Legen Sie die Zelle in einen Vakuum-Exsikkator, damit der Redox-Mediator den Innenraum der zusammengesetzten Zelle füllen kann. </li></ol> 6. JV Kurvencharakterisierung <ol><li> Erfassen Sie die JV-Kurven mit einem digitalen Quellzähler unter 100 mW / cm 2 Beleuchtung aus einer Xenon-Bogen-Quelle, die durch ein AM1.5G-Filter geführt wird. </li></ol>

<ol>
	<li>O'Regan, B., Gr&#228;tzel, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+low-cost,+high-efficiency+solar+cell+based+on+dye-sensitized+colloidal+TiO2+films.">A low-cost, high-efficiency solar cell based on dye-sensitized colloidal TiO2 films.</a> Nature. 353 (6346), 737-740 (1991).</li><li>Lee, C. H., Chiu, W. H., Lee, K. M., Hsieh, W. F., Wu, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improved+performance+of+flexible+dye-sensitized+solar+cells+by+introducing+an+interfacial+layer+on+Ti+substrates.">Improved performance of flexible dye-sensitized solar cells by introducing an interfacial layer on Ti substrates.</a> J Mat Chem. 21 (13), 5114-5119 (2011).</li><li>Burschka, J., Pellet, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sequential+deposition+as+a+route+to+high-performance+perovskite-sensitized+solar+cells.">Sequential deposition as a route to high-performance perovskite-sensitized solar cells.</a> Nature. 499 (7458), 316-319 (2013).</li><li>Ohsaki, Y., Masaki, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dye-sensitized+TiO2+nanotube+solar+cells:+fabrication+and+electronic+characterization.">Dye-sensitized TiO2 nanotube solar cells: fabrication and electronic characterization.</a> Phys Chem Chem Phys. 7 (24), 4157-4163 (2005).</li><li>Mor, G. K., Shankar, K., Paulose, M., Varghese, O. K., Grimes, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enhanced+Photocleavage+of+Water+Using+Titania+Nanotube+Arrays.">Enhanced Photocleavage of Water Using Titania Nanotube Arrays.</a> Nano Letters. 5 (1), 191-195 (2005).</li><li>Feng, X., Shankar, K., Varghese, O. K., Paulose, M., Latempa, T. J., Grimes, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vertically+Aligned+Single+Crystal+TiO2+Nanowire+Arrays+Grown+Directly+on+Transparent+Conducting+Oxide+Coated+Glass:+Synthesis+Details+and+Applications.">Vertically Aligned Single Crystal TiO2 Nanowire Arrays Grown Directly on Transparent Conducting Oxide Coated Glass: Synthesis Details and Applications.</a> Nano Letters. 8 (11), 3781-3786 (2008).</li><li>Roy, P., Berger, S., Schmuki, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TiO2+Nanotubes:+Synthesis+and+Applications.">TiO2 Nanotubes: Synthesis and Applications.</a> Angewandte Chemie International Edition. 50 (13), 2904-2939 (2011).</li><li>Macdonald, T. J., Xu, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=NiO+Nanofibers+as+a+Candidate+for+a+Nanophotocathode.">NiO Nanofibers as a Candidate for a Nanophotocathode.</a> Nanomaterials. 4 (2), 256-266 (2014).</li><li>Chuangchote, S., Sagawa, T., Yoshikawa, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+dye-sensitized+solar+cells+using+electrospun+TiO2+nanofibers+as+a+light+harvesting+layer.">Efficient dye-sensitized solar cells using electrospun TiO2 nanofibers as a light harvesting layer.</a> Appl Phys Lett. 93 (3), 033310 (2008).</li><li>Li, D., Xia, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrospinning+of+Nanofibers:+Reinventing+the+Wheel?.">Electrospinning of Nanofibers: Reinventing the Wheel?.</a> Adv Mat. 16 (14), 1151-1170 (2004).</li><li>Li, W. J., Laurencin, C. T., Caterson, E. J., Tuan, R. S., Ko, F. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrospun+nanofibrous+structure:+A+novel+scaffold+for+tissue+engineering.">Electrospun nanofibrous structure: A novel scaffold for tissue engineering.</a> J Biomed Mat Res. 60 (4), 613-621 (2002).</li><li>Jia, H., Zhu, G., Vugrinovich, B., Kataphinan, W., Reneker, D. H., Wang, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enzyme-Carrying+Polymeric+Nanofibers+Prepared+via+Electrospinning+for+Use+as+Unique+Biocatalysts.">Enzyme-Carrying Polymeric Nanofibers Prepared via Electrospinning for Use as Unique Biocatalysts.</a> Biotechnol Prog. 18 (5), 1027-1032 (2002).</li><li>Mai, L., Xu, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrospun+Ultralong+Hierarchical+Vanadium+Oxide+Nanowires+with+High+Performance+for+Lithium+Ion+Batteries.">Electrospun Ultralong Hierarchical Vanadium Oxide Nanowires with High Performance for Lithium Ion Batteries.</a> Nano Letters. 10 (11), 4750-4755 (2010).</li><li>Cai, J., Niu, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-Performance+Supercapacitor+Electrode+Materials+from+Cellulose-Derived+Carbon+Nanofibers.">High-Performance Supercapacitor Electrode Materials from Cellulose-Derived Carbon Nanofibers.</a> ACS Appl Mat Interfaces. 7 (27), 14946-14953 (2015).</li><li>Joshi, P., Zhang, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Composite+of+TiO2+nanofibers+and+nanoparticles+for+dye-sensitized+solar+cells+with+significantly+improved+efficiency.">Composite of TiO2 nanofibers and nanoparticles for dye-sensitized solar cells with significantly improved efficiency.</a> Energ Environ Sci. 3 (10), 1507-1510 (2010).</li><li>Macdonald, T. J., Tune, D. D., Dewi, M. R., Gibson, C. T., Shapter, J. G., Nann, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+TiO2+Nanofiber-Carbon+Nanotube-Composite+Photoanode+for+Improved+Efficiency+in+Dye-Sensitized+Solar+Cells.">A TiO2 Nanofiber-Carbon Nanotube-Composite Photoanode for Improved Efficiency in Dye-Sensitized Solar Cells.</a> ChemSusChem. 8 (20), 3396-3400 (2015).</li><li>Teo, W. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Electrospinning parameters and fiber control. , (2015).</li></ol>

Die Autoren haben nichts zu offenbaren.

Die in dieser Arbeit vorgestellten Methoden beschreiben die Herstellung von effizienten nanofaserigen Photoanoden für photokatalytische Geräte wie DSSCs. Electrospinning ist eine sehr vielseitige Technik für die Herstellung von Nanofasern, aber ein gewisses Maß an Geschick und Wissen ist erforderlich, um Materialien mit optimalen Morphologien zu erhalten. Einer der kritischsten Aspekte, um gute Nanofasern zu erhalten, ist die Vorbereitung der Vorläuferlösung: Es gibt einige Schlüsselfaktoren wie die Konzentration...

Dye-sensibilisierte Solarzellen (DSSCs) sind eine interessante Alternative zu Silizium-Solarzellen 1 dank ihrer geringen Kosten, dem relativ einfachen Herstellungsprozess und der Leichtigkeit der Großproduktion. Ein weiterer Vorteil ist ihr Potenzial, in flexible Substrate eingebaut zu werden, ein deutlicher Vorteil gegenüber Silizium-Solarzellen 2 . Ein typischer DSSC nutzt: (1) ein mit einem Farbstoff sensibilisierter nanopartikulärer TiO 2 -Analanode als lichtgewachsene Schicht; (2) eine Pt-beschichtete FTO, die als Gegenelektrode verwendet wird; Und (3) einen Elektrolyten, der ein Redoxpaar wie I - / I 3 - enthält , das zwischen den beiden Elektroden angeordnet ist und als &quot;lochleitendes Medium&quot; arbeitet. Obwohl DSSCs Wirkungsgrade von 15% 3 übertroffen haben, wird die Leistung von Nanopartikel-basierten Photoanoden immer noch durch eine Reihe von Einschränkungen behindert, einschließlich langsamer ElektronenmobilisierungY 4 , schlechte Absorption von niederenergetischen Photonen 5 und Ladungsrekombination 6 . Der Elektronensammelwirkungsgrad hängt stark von der Geschwindigkeit des Elektronentransports durch die TiO 2 -Nanopartikelschicht ab. Wenn die Ladungsdiffusion langsam ist, erhöht sich die Wahrscheinlichkeit der Rekombination mit I 3 - in der Elektrolytlösung, was zu einem Verlust an Effizienz führt. Es wurde gezeigt, dass das Ersetzen von nanopartikulärem TiO 2 mit eindimensionalen (1D) TiO 2 -Nanoarchitekturen den Ladungstransport durch Verringerung der Streuung von freien Elektronen aus den Korngrenzen der miteinander verbundenen TiO 2 -Nanopartikel 7 verbessern kann. Da 1D-Nanostrukturen einen direkteren Weg zur Ladungssammlung bieten, können wir erwarten, dass der Elektronentransport in Nanofasern (NFs) deutlich schneller als in Nanopartikeln 8 , </sup&gt; 9 Das Elektrospinnen ist eines der am häufigsten verwendeten Verfahren zur Herstellung von Fasermaterialien mit Submikrometer-Durchmessern 10 . Diese Technik beinhaltet die Verwendung von Hochspannung, um den Ausstoß eines Polymerlösungsstrahls durch eine Spinndüse zu induzieren. Aufgrund der Biegeinstabilität wird dieser Strahl anschließend oftmals zu kontinuierlichen Nanofasern gedehnt. In den letzten Jahren wurde diese Technik weitgehend zur Herstellung von polymeren und anorganischen Materialien verwendet, die für zahlreiche und vielfältige Anwendungen wie Tissue Engineering 11 , Katalyse 12 und als Elektrodenmaterialien für Lithium-Ionen-Batterien 13 und Superkondensatoren verwendet wurden. Die Verwendung von elektrogesponnenen TiO 2 -NFs als Streuschicht in der Photoanode kann die Leistung von DSSCs erhöhen. Allerdings photoanodes mit nanofibroUns Architekturen neigen dazu, eine schlechte Farbstoffabsorption aufgrund von Oberflächenbeschränkungen zu haben. Eine der möglichen Lösungen, um dies zu überwinden, besteht darin, NFs und Nanopartikel zu mischen. Es wurde gezeigt, dass sich zusätzliche Streuschichten ergeben, wodurch die Lichtabsorption und der Gesamtwirkungsgrad verbessert werden. Das in diesem Video präsentierte Protokoll bietet ein einfaches Verfahren zur Synthese von ultralong-TiO 2 -Nanofasern durch eine Kombination von Elektrospinn- und Sol-Gel-Techniken, gefolgt von einem Kalzinierungsverfahren. Das Protokoll veranschaulicht dann die Verwendung der TiO 2 -NFs in Kombination mit nanopartikulärem TiO 2 für die Herstellung eines zweischichtigen Photoanodes mit verbesserter Lichtstreuungsfähigkeit unter Verwendung von Rakeltechniken sowie die anschließende Montage eines DSSC unter Verwendung eines solchen Photoanode

<table border="0" cellpadding="0" cellspacing="0" width="689">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">titanium(IV) n-butoxide</td>
			<td style="width:149px;">Sigma-Aldrich</td>
			<td align="right" style="width:127px;">244112</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Polyvinylpyrrolidone</td>
			<td style="width:149px;">Sigma-Aldrich</td>
			<td align="right" style="width:127px;">437190</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">glacial acetic acid</td>
			<td style="width:149px;">Sigma-Aldrich</td>
			<td style="width:127px;">A6283</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Ethanol, absolute</td>
			<td style="width:149px;">Fisher Scientific</td>
			<td style="width:127px;">E/0650DF/17</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">20 mL Sample vials</td>
			<td style="width:149px;">(any)</td>
			<td style="width:127px;"></td>
			<td>(or larger volume)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">disposable 21G needle</td>
			<td style="width:149px;">(any)</td>
			<td style="width:127px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">P150 grit sandpaper</td>
			<td style="width:149px;">(any)</td>
			<td style="width:127px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">disposable 10mL syringe</td>
			<td style="width:149px;">(any)</td>
			<td style="width:127px;"></td>
			<td>(or larger volume)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">magnetic stirrer + stirring bar</td>
			<td style="width:149px;">(any)</td>
			<td style="width:127px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">PHD 2000 syringe pump</td>
			<td style="width:149px;">Harvard Apparatus</td>
			<td style="width:127px;">71-2002</td>
			<td>(or any other syringe pump capable of outputting a 1mL/hr flow</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Aluminium foil</td>
			<td style="width:149px;">(any)</td>
			<td style="width:127px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Stainless steel collector plate</td>
			<td style="width:149px;">(custom built)</td>
			<td style="width:127px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:247px;">High Voltage Power Source</td>
			<td style="width:149px;">Gamma High Voltage Research, Inc</td>
			<td style="width:127px;">ES30P-10W</td>
			<td>(or any other power supply capable of outputting +15 kV</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Polycarbonate protective shield</td>
			<td style="width:149px;">(custom built)</td>
			<td style="width:127px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Ceramic crucible</td>
			<td style="width:149px;">(any)</td>
			<td style="width:127px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Muffle furnace</td>
			<td style="width:149px;">(any)</td>
			<td style="width:127px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Titanium dioxide, nanopowder</td>
			<td style="width:149px;">Sigma-Aldrich</td>
			<td align="right" style="width:127px;">718467</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">50 mL 1-neck round bottom flasks</td>
			<td style="width:149px;">(any)</td>
			<td style="width:127px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">bath sonicator</td>
			<td style="width:149px;">(any)</td>
			<td style="width:127px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Terpineol</td>
			<td style="width:149px;">Sigma-Aldrich</td>
			<td style="width:127px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Rotary evaporator</td>
			<td style="width:149px;">(any)</td>
			<td style="width:127px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">FTO glass</td>
			<td style="width:149px;">Solaronix</td>
			<td>TCO30-10/LI</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Adhesive tape</td>
			<td style="width:149px;">(any)</td>
			<td style="width:127px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">razor blade</td>
			<td style="width:149px;">(any)</td>
			<td style="width:127px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">SEM</td>
			<td style="width:149px;">JEOL</td>
			<td style="width:127px;">6500F</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">XRD</td>
			<td style="width:149px;">PANalytical&#160;</td>
			<td style="width:127px;">X&#39;pert Pro</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Titanium Tetrachloride</td>
			<td style="width:149px;">Sigma-Aldrich</td>
			<td align="right" style="width:127px;">89545</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Ruthenizer&#160; 535-bisTBA</td>
			<td style="width:149px;">Solaronix</td>
			<td style="width:127px;">N719</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">sealing film</td>
			<td style="width:149px;">Dyesol</td>
			<td>Meltonix 1170-25</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Pt-coated FTO</td>
			<td style="width:149px;">Solaronix</td>
			<td>TCO30-10/LI</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">1-propyl-3-methylimidazolium iodide</td>
			<td style="width:149px;">Sigma-Aldrich</td>
			<td align="right" style="width:127px;">49637</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Iodine</td>
			<td style="width:149px;">Sigma-Aldrich</td>
			<td align="right" style="width:127px;">207772</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">benzimidazole</td>
			<td style="width:149px;">Sigma-Aldrich</td>
			<td align="right" style="width:127px;">194123</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">3-Methoxypropionitrile</td>
			<td style="width:149px;">Sigma-Aldrich</td>
			<td align="right" style="width:127px;">65290</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Digital source meter</td>
			<td style="width:149px;">Keithley</td>
			<td align="right" style="width:127px;">2400</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:247px;">Solar Simulator</td>
			<td style="width:149px;">Abet technologies</td>
			<td align="right" style="width:127px;">10500</td>
			<td></td>
		</tr>
	</tbody>
</table>

electrospinning of photocatalytic electrodes for dye-sensitized solar cells

Diese Arbeit veranschaulicht ein Protokoll zur Herstellung eines faserbasierten Photoanodens für farbstoffsensibilisierte Solarzellen, bestehend aus einer lichtstreuenden Schicht aus elektrogesponnenen Titandioxid-Nanofasern (TiO 2 -NFs) auf einer Sperrschicht aus handelsüblichem Titandioxid Nanopartikel (TiO 2 -NPs). Dies wird durch erstes Elektrospinnen einer Lösung von Titan (IV) butoxid, Polyvinylpyrrolidon (PVP) und Eisessig in Ethanol erreicht, um zusammengesetzte PVP / TiO 2 -Nanofasern zu erhalten. Diese werden dann bei 500 ° C calciniert, um das PVP zu entfernen und reine Anatasphasen-Titandioxid-Nanofasern zu erhalten. Dieses Material zeichnet sich durch Rasterelektronenmikroskopie (SEM) und Pulverröntgenbeugung (XRD) aus. Die Photoanode wird hergestellt, indem zuerst eine Sperrschicht durch die Abscheidung einer TiO &amp; sub2; -NPs / Terpineol-Aufschlämmung auf einem mit einem Fluor-dotierten Zinnoxid (FTO) -Glasschlitten unter Verwendung von Rakeltechniken hergestellt wird. Eine anschließende thermische BehandlungWird bei 500 ° C durchgeführt. Dann wird die lichtstreuende Schicht durch Abscheiden einer TiO &amp; sub2; -NFs / Terpineol-Aufschlämmung auf demselben Objektträger unter Verwendung derselben Technik und Calcinieren bei 500ºC gebildet. Die Leistung des Photoanodens wird durch die Herstellung einer farbstoffsensibilisierten Solarzelle getestet und deren Effizienz durch JV-Kurven unter einer Reihe von einfallenden Lichtdichten von 0,25-1 Sun gemessen.

Die TiO 2 -Nanofasern wurden unter Verwendung von SEM, Röntgen-Photoelektronenspektroskopie (XPS) und XRD charakterisiert. Die Nanostruktur des Photoanodes wurde durch SEM charakterisiert. Die Leistung des montierten DSSC wurde mit einem Solarsimulator und einer Quellmesseinheit getestet. Das SEM-Bild in Fig. 1A zeigt, daß die unter Verwendung dieses Protokolls synthetisierten Nanofas...

Watch this Scientific Journal Video about Electrospinning of Photocatalytic Electrodes for Dye-sensitized Solar Cells at JoVE.com

Electrospinning of Photocatalytic Electrodes for Dye-sensitized Solar Cells

Das übergeordnete Ziel dieses Projektes war es, das Elektrospinnen zu verwenden, um eine Photoanode mit verbesserter Leistung für farbstoffsensibilisierte Solarzellen herzustellen.

Elektrospinnen von photokatalytischen Elektroden für farbstoffsensibilisierte Solarzellen

This work demonstrates a protocol to fabricate a fiber-based photoanode for dye-sensitized solar cells, consisting of a light-scattering layer made of ...

electrospinning-photocatalytic-electrodes-for-dye-sensitized-solar

Research

JoVE Journal

Engineering

9.6K Aufrufe.  Victoria University of Wellington.  Das übergeordnete Ziel dieses Projektes war es, das Elektrospinnen zu verwenden, um eine Photoanode mit verbesserter Leistung für farbstoffsensibilisierte Solarzellen herzustellen. 

Serie: Electrospinning of Photocatalytic Electrodes for Dye-sensitized Solar Cells

Polycrystalline Silicon Thin-film Solar cells with Plasmonic-enhanced Light-trapping

One of major approaches to cheaper solar cells is reducing the amount of semiconductor material used for their fabrication and making cells thinner. To compensate for lower light absorption such physically thin devices have to incorporate light-trapping which increases their optical thickness. Light scattering by textured surfaces is a common technique but it cannot be universally applied to all solar cell technologies. Some cells, for example those made of evaporated silicon, are planar as produced and they require an alternative light-trapping means suitable for planar devices. Metal nanoparticles formed on planar silicon cell surface and capable of light scattering due to surface plasmon resonance is an effective approach.
The paper presents a fabrication procedure of evaporated polycrystalline silicon solar cells with plasmonic light-trapping and demonstrates how the cell quantum efficiency improves due to presence of metal nanoparticles.
To fabricate the cells a film consisting of alternative boron and phosphorous doped silicon layers is deposited on glass substrate by electron beam evaporation. An Initially amorphous film is crystallised and electronic defects are mitigated by annealing and hydrogen passivation. Metal grid contacts are applied to the layers of opposite polarity to extract electricity generated by the cell. Typically, such a ~2 &mu;m thick cell has a short-circuit current density (Jsc) of 14-16 mA/cm2, which can be increased up to 17-18 mA/cm2 (~25% higher) after application of a simple diffuse back reflector made of a white paint.
To implement plasmonic light-trapping a silver nanoparticle array is formed on the metallised cell silicon surface. A precursor silver film is deposited on the cell by thermal evaporation and annealed at 23&deg;C to form silver nanoparticles. Nanoparticle size and coverage, which affect plasmonic light-scattering, can be tuned for enhanced cell performance by varying the precursor film thickness and its annealing conditions. An optimised nanoparticle array alone results in cell Jsc enhancement of about 28%, similar to the effect of the diffuse reflector. The photocurrent can be further increased by coating the nanoparticles by a low refractive index dielectric, like MgF2, and applying the diffused reflector. The complete plasmonic cell structure comprises the polycrystalline silicon film, a silver nanoparticle array, a layer of MgF2, and a diffuse reflector. The Jsc for such cell is 21-23 mA/cm2, up to 45% higher than Jsc of the original cell without light-trapping or ~25% higher than Jsc for the cell with the diffuse reflector only.
Introduction
Light-trapping in silicon solar cells is commonly achieved via light scattering at textured interfaces. Scattered light travels through a cell at oblique angles for a longer distance and when such angles exceed the critical angle at the cell interfaces the light is permanently trapped in the cell by total internal reflection (Animation 1: Light-trapping). Although this scheme works well for most solar cells, there are developing technologies where ultra-thin Si layers are produced planar (e.g. layer-transfer technologies and epitaxial c-Si layers) 1 and or when such layers are not compatible with textures substrates (e.g. evaporated silicon) 2. For such originally planar Si layer alternative light trapping approaches, such as diffuse white paint reflector 3, silicon plasma texturing 4 or high refractive index nanoparticle reflector 5 have been suggested.
Metal nanoparticles can effectively scatter incident light into a higher refractive index material, like silicon, due to the surface plasmon resonance effect 6. They also can be easily formed on the planar silicon cell surface thus offering a light-trapping approach alternative to texturing. For a nanoparticle located at the air-silicon interface the scattered light fraction coupled into silicon exceeds 95% and a large faction of that light is scattered at angles above critical providing nearly ideal light-trapping condition (Animation 2: Plasmons on NP). The resonance can be tuned to the wavelength region, which is most important for a particular cell material and design, by varying the nanoparticle average size, surface coverage and local dielectric environment 6,7. Theoretical design principles of plasmonic nanoparticle solar cells have been suggested 8. In practice, Ag nanoparticle array is an ideal light-trapping partner for poly-Si thin-film solar cells because most of these design principle are naturally met. The simplest way of forming nanoparticles by thermal annealing of a thin precursor Ag film results in a random array with a relatively wide size and shape distribution, which is particularly suitable for light-trapping because such an array has a wide resonance peak, covering the wavelength range of 700-900 nm, important for poly-Si solar cell performance. The nanoparticle array can only be located on the rear poly-Si cell surface thus avoiding destructive interference between incident and scattered light which occurs for front-located nanoparticles 9. Moreover, poly-Si thin-film cells do not requires a passivating layer and the flat base-shaped nanoparticles (that naturally result from thermal annealing of a metal film) can be directly placed on silicon further increases plasmonic scattering efficiency due to surface plasmon-polariton resonance 10.
The cell with the plasmonic nanoparticle array as described above can have a photocurrent about 28% higher than the original cell. However, the array still transmits a significant amount of light which escapes through the rear of the cell and does not contribute into the current. This loss can be mitigated by adding a rear reflector to allow catching transmitted light and re-directing it back to the cell. Providing sufficient distance between the reflector and the nanoparticles (a few hundred nanometers) the reflected light will then experience one more plasmonic scattering event while passing through the nanoparticle array on re-entering the cell and the reflector itself can be made diffuse - both effects further facilitating light scattering and hence light-trapping. Importantly, the Ag nanoparticles have to be encapsulated with an inert and low refractive index dielectric, like MgF2 or SiO2, from the rear reflector to avoid mechanical and chemical damage 7. Low refractive index for this cladding layer is required to maintain a high coupling fraction into silicon and larger scattering angles, which are ensured by the high optical contrast between the media on both sides of the nanoparticle, silicon and dielectric 6. The photocurrent of the plasmonic cell with the diffuse rear reflector can be up to 45% higher than the current of the original cell or up to 25% higher than the current of an equivalent cell with the diffuse reflector only.

Polycrystalline silicon thin-film solar cells on glass are fabricated by deposition of boron and phosphorous doped silicon layers followed by crystallisation, defect passivation and metallisation. Plasmonic light-trapping is introduced by forming Ag nanoparticles on the silicon cell surface capped with a diffused reflector resulting in ~45% photocurrent enhancement.

Polykristalline Silizium-Dünnschicht-Solarzellen mit Plasmonische-enhanced Light-Trapping

One of major approaches to cheaper solar cells is reducing the amount of semiconductor material used for their fabrication and making cells thinner. To ...

Forschung

Ingenieurwesen

Harvesting Solar Energy by Means of Charge-Separating Nanocrystals and Their Solids

Conjoining different semiconductor materials in a single nano-composite provides synthetic means for the development of novel optoelectronic materials offering a superior control over the spatial distribution of charge carriers across material interfaces. As this study demonstrates, a combination of donor-acceptor nanocrystal (NC) domains in a single nanoparticle can lead to the realization of efficient photocatalytic1-5 materials, while a layered assembly of donor- and acceptor-like nanocrystals films gives rise to photovoltaic materials.
Initially the paper focuses on the synthesis of composite inorganic nanocrystals, comprising linearly stacked ZnSe, CdS, and Pt domains, which jointly promote photoinduced charge separation. These structures are used in aqueous solutions for the photocatalysis of water under solar radiation, resulting in the production of H2 gas. To enhance the photoinduced separation of charges, a nanorod morphology with a linear gradient originating from an intrinsic electric field is used5. The inter-domain energetics are then optimized to drive photogenerated electrons toward the Pt catalytic site while expelling the holes to the surface of ZnSe domains for sacrificial regeneration (via methanol). Here we show that the only efficient way to produce hydrogen is to use electron-donating ligands to passivate the surface states by tuning the energy level alignment at the semiconductor-ligand interface. Stable and efficient reduction of water is allowed by these ligands due to the fact that they fill vacancies in the valence band of the semiconductor domain, preventing energetic holes from degrading it. Specifically, we show that the energy of the hole is transferred to the ligand moiety, leaving the semiconductor domain functional. This enables us to return the entire nanocrystal-ligand system to a functional state, when the ligands are degraded, by simply adding fresh ligands to the system4.
To promote a photovoltaic charge separation, we use a composite two-layer solid of PbS and TiO2 films. In this configuration, photoinduced electrons are injected into TiO2 and are subsequently picked up by an FTO electrode, while holes are channeled to a Au electrode via PbS layer6. To develop the latter we introduce a Semiconductor Matrix Encapsulated Nanocrystal Arrays (SMENA) strategy, which allows bonding PbS NCs into the surrounding matrix of CdS semiconductor. As a result, fabricated solids exhibit excellent thermal stability, attributed to the heteroepitaxial structure of nanocrystal-matrix interfaces, and show compelling light-harvesting performance in prototype solar cells7.

A general strategy for the development of charge-separating semiconductor nanocrystal composites deployable for solar energy production is presented. We show that assembly of donor-acceptor nanocrystal domains in a single nanoparticle geometry gives rise to a photocatalytic function, while bulk-heterojunctions of donor-acceptor nanocrystal films can be used for photovoltaic energy conversion.

Harvesting Solar Energy mittels Charge-Trennung Nanokristalle und ihre Solids

Conjoining different semiconductor materials in a single nano-composite provides synthetic means for the development of novel optoelectronic materials ...

Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light

The poor response of dye-sensitized solar cells (DSCs) to red and infrared light is a significant impediment to the realization of higher photocurrents and hence higher efficiencies. Photon up-conversion by way of triplet-triplet annihilation (TTA-UC) is an attractive technique for using these otherwise wasted low energy photons to produce photocurrent, while not interfering with the photoanodic performance in a deleterious manner. Further to this, TTA-UC has a number of features, distinct from other reported photon up-conversion technologies, which renders it particularly suitable for coupling with DSC technology. In this work, a proven high performance TTA-UC system, comprising a palladium porphyrin sensitizer and rubrene emitter, is combined with a high performance DSC (utilizing the organic dye D149) in an integrated device. The device shows an enhanced response to sub-bandgap light over the absorption range of the TTA-UC sub-unit resulting in the highest figure of merit for up-conversion assisted DSC performance to date.

An integrated device, incorporating a dye-sensitized solar cell and triplet-triplet annihilation up-conversion unit was produced, affording enhanced light harvesting, from a wider section of the solar spectrum. Under modest irradiation levels a significantly enhanced response to low energy photons was demonstrated, yielding a record figure of merit for dye-sensitized solar cells.

Integration einer Triplett-Triplett-Annihilation Up-Conversion-System, um Farbstoffsolarzellantwort auf Sub-Bandgap-Licht Enhance

The poor response of dye-sensitized solar cells (DSCs) to red and infrared light is a significant impediment to the realization of higher photocurrents ...

Ambient Method for the Production of an Ionically Gated Carbon Nanotube Common Cathode in Tandem Organic Solar Cells

A method of fabricating organic photovoltaic (OPV) tandems that requires no vacuum processing is presented. These devices are comprised of two solution-processed polymeric cells connected in parallel by a transparent carbon nanotubes (CNT) interlayer. This structure includes improvements in fabrication techniques for tandem OPV devices. First the need for ambient-processed cathodes is considered. The CNT anode in the tandem device is tuned via ionic gating to become a common cathode. Ionic gating employs electric double layer charging to lower the work function of the CNT electrode. Secondly, the difficulty of sequentially stacking tandem layers by solution-processing is addressed. The devices are fabricated via solution and dry-lamination in ambient conditions with parallel processing steps. The method of fabricating the individual polymeric cells, the steps needed to laminate them together with a common CNT cathode, and then provide some representative results are described. These results demonstrate ionic gating of the CNT electrode to create a common cathode and addition of current and efficiency as a result of the lamination procedure.

A method of fabricating, in ambient conditions, organic photovoltaic tandem devices in a parallel configuration is presented. These devices feature an air-processed, semi-transparent, carbon nanotube common cathode.

Ambient Verfahren zur Herstellung eines ionisch Gated Carbon Nanotube Gemeinsame Kathode in Tandem Organische Solarzellen

A method of fabricating organic photovoltaic (OPV) tandems that requires no vacuum processing is presented. These devices are comprised of two ...

Making Record-efficiency SnS Solar Cells by Thermal Evaporation and Atomic Layer Deposition

Tin sulfide (SnS) is a candidate absorber material for Earth-abundant, non-toxic solar cells. SnS offers easy phase control and rapid growth by congruent thermal evaporation, and it absorbs visible light strongly. However, for a long time the record power conversion efficiency of SnS solar cells remained below 2%. Recently we demonstrated new certified record efficiencies of 4.36% using SnS deposited by atomic layer deposition, and 3.88% using thermal evaporation. Here the fabrication procedure for these record solar cells is described, and the statistical distribution of the fabrication process is reported. The standard deviation of efficiency measured on a single substrate is typically over 0.5%. All steps including substrate selection and cleaning, Mo sputtering for the rear contact (cathode), SnS deposition, annealing, surface passivation, Zn(O,S) buffer layer selection and deposition, transparent conductor (anode) deposition, and metallization are described. On each substrate we fabricate 11 individual devices, each with active area 0.25 cm2. Further, a system for high throughput measurements of current-voltage curves under simulated solar light, and external quantum efficiency measurement with variable light bias is described. With this system we are able to measure full data sets on all 11 devices in an automated manner and in minimal time. These results illustrate the value of studying large sample sets, rather than focusing narrowly on the highest performing devices. Large data sets help us to distinguish and remedy individual loss mechanisms affecting our devices.

Tin sulfide (SnS) is a candidate material for Earth-abundant, non-toxic solar cells. Here, we demonstrate the fabrication procedure of the SnS solar cells employing atomic layer deposition, which yields 4.36% certified power conversion efficiency, and thermal evaporation which yields 3.88%.

Erstellen Rekordeffizienz SnS Solarzellen durch thermische Verdampfung und Atomic Layer Deposition

Tin sulfide (SnS) is a candidate absorber material for Earth-abundant, non-toxic solar cells. SnS offers easy phase control and rapid growth by congruent ...

Integration of Light Trapping Silver Nanostructures in Hydrogenated Microcrystalline Silicon Solar Cells by Transfer Printing

One of the potential applications of metal nanostructures is light trapping in solar cells, where unique optical properties of nanosized metals, commonly known as plasmonic effects, play an important role. Research in this field has, however, been impeded owing to the difficulty of fabricating devices containing the desired functional metal nanostructures. In order to provide a viable strategy to this issue, we herein show a transfer printing-based approach that allows the quick and low-cost integration of designed metal nanostructures with a variety of device architectures, including solar cells. Nanopillar poly(dimethylsiloxane) (PDMS) stamps were fabricated from a commercially available nanohole plastic film as a master mold. On this nanopatterned PDMS stamps, Ag films were deposited, which were then transfer-printed onto block copolymer (binding layer)-coated hydrogenated microcrystalline Si (&#181;c-Si:H) surface to afford ordered Ag nanodisk structures. It was confirmed that the resulting Ag nanodisk-incorporated &#181;c-Si:H solar cells show higher performances compared to a cell without the transfer-printed Ag nanodisks, thanks to plasmonic light trapping effect derived from the Ag nanodisks. Because of the simplicity and versatility, further device application would also be feasible thorough this approach.

A viable transfer printing-based methodology to introduce plasmonic metal nanostructures in solar cells is described. Using nanopillar poly(dimethylsiloxane) stamps, an Ag-based ordered nanodisk array was integrated with standard hydrogenated microcrystalline Si solar cells, which led to improved device performances due to plasmonic light trapping.

Integration of Light Trapping Silber-Nanostrukturen in Hydrogenated Microcrystalline Silicon Solar Cells durch Transferdruck

One of the potential applications of metal nanostructures is light trapping in solar cells, where unique optical properties of nanosized metals, commonly ...

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices have used devices prepared by spin coating, a process that is not amenable to large-scale fabrication. This mismatch in device fabrication makes it difficult to translate quantitative results obtained in the laboratory to the commercial level, making optimization difficult. Using a mini-slot die coater, this mismatch can be resolved by translating the commercial process to the laboratory and characterizing the structure formation in the active layer of the device in real time and in situ as films are coated onto a substrate. The evolution of the morphology was characterized under different conditions, allowing us to propose a mechanism by which the structures form and grow. This mini-slot die coater offers a simple, convenient, material efficient route by which the morphology in the active layer can be optimized under industrially relevant conditions. The goal of this protocol is to show experimental details of how a solar cell device is fabricated using a mini-slot die coater and technical details of running in situ structure characterization using the mini-slot die coater.

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

Here, we present a protocol to fabricate organic thin film solar cells using a mini-slot die coater and related in-line structure characterizations using synchrotron scattering techniques.

Printing Herstellung von Bulk-Heterosolarzellen und<em&gt; In Situ</em&gt; Morphologie Charakterisierung

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices ...

Digital Printing of Titanium Dioxide for Dye Sensitized Solar Cells

Silicon solar cell manufacturing is an expensive and high energy consuming process. In contrast, dye sensitized solar cell production is less environmentally damaging with lower processing temperatures presenting a viable and low cost alternative to conventional production. This paper further enhances these environmental credentials by evaluating the digital printing and therefore additive production route for these cells. This is achieved here by investigating the formation and performance of a metal oxide photoelectrode using nanoparticle sized titanium dioxide. An ink-jettable material was formulated, characterized and printed with a piezoelectric inkjet head to produce a 2.6 &#181;m thick layer. The resultant printed layer was fabricated into a functioning cell with an active area of 0.25 cm2 and a power conversion efficiency of 3.5%. The binder-free formulation resulted in a reduced processing temperature of 250 &#176;C, compatible with flexible polyamide substrates which are stable up to temperatures of 350 &#730;C. The authors are continuing to develop this process route by investigating inkjet printing of other layers within dye sensitized solar cells.

This paper investigates the suitability of inkjet printing for the manufacturing of dye-sensitized solar cells. A binder-free TiO2 nanoparticle ink was formulated and printed onto a FTO glass substrate. The printed layer was fabricated into a cell with an active area of 0.25 cm2 and an efficiency of 3.5%.

Digitaldruck von Titandioxid für farbstoffsensibilisierte Solarzellen

Silicon solar cell manufacturing is an expensive and high energy consuming process. In contrast, dye sensitized solar cell production is less ...

Monovalent Cation Doping of CH3NH3PbI3 for Efficient Perovskite Solar Cells

Here, we demonstrate the incorporation of monovalent cation additives into CH3NH3PbI3 perovskite in order to adjust the optical, excitonic, and electrical properties. The possibility of doping was investigated by adding monovalent cation halides with similar ionic radii to Pb2+, including Cu+, Na+, and Ag+. A shift in the Fermi level and a remarkable decrease of sub-bandgap optical absorption, along with a lower energetic disorder in the perovskite, was achieved. An order-of-magnitude enhancement in the bulk hole mobility and a significant reduction of transport activation energy within an additive-based perovskite device was attained. The confluence of the aforementioned improved properties in the presence of these cations led to an enhancement in the photovoltaic parameters of the perovskite solar cell. An increase of 70 mV in open circuit voltage for AgI and a 2 mA/cm2 improvement in photocurrent density for NaI- and CuBr-based solar cells were achieved compared to the pristine device. Our work paves the way for further improvements in the optoelectronic quality of CH3NH3PbI3 perovskite and subsequent devices. It highlights a new avenue for investigations on the role of dopant impurities in crystallization and controls the electronic defect density in perovskite structures.

Monovalent Cation Doping of CH3NH3PbI3 for Efficient Perovskite Solar Cells

Here, we present a protocol to adjust the properties of solution-processed CH3NH3PbI3 through the incorporation of monovalent cation additives in order to achieve highly efficient perovskite solar cells.

Einwertiges Kation Dotierung von CH<sub&gt; 3</sub&gt; NH<sub&gt; 3</sub&gt; PbI<sub&gt; 3</sub&gt; Für effiziente Perowskit-Solarzellen

Here, we demonstrate the incorporation of monovalent cation additives into CH3NH3PbI3 perovskite in order to adjust the optical, excitonic, and electrical ...

In Situ Monitoring of the Accelerated Performance Degradation of Solar Cells and Modules: A Case Study for Cu(In,Ga)Se2 Solar Cells

The levelized cost of electricity (LCOE) of photovoltaic (PV) systems is determined by, among other factors, the PV module reliability. Better prediction of degradation mechanisms and prevention of module field failure can consequently decrease investment risks as well as increase the electricity yield. An improved knowledge level can for these reasons significantly decrease the total costs of PV electricity. 
In order to better understand and minimize the degradation of PV modules, the occurring degradation mechanisms and conditions should be identified. This should preferably happen under combined stresses, since modules in the field are also simultaneously exposed to multiple stress factors. Therefore, two 'Combined Stress test with in situ measurement' setups have been designed and constructed. These setups allow the simultaneous use of humidity, temperature, illumination, and electrical biases as independently controlled stress factors on solar cells and minimodules. The setups also allow real-time monitoring of the electrical properties of these samples. This protocol presents these setups and describes the experimental possibilities. Moreover, results obtained with these setups are also presented: various examples about the influence of both deposition and degradation conditions on the stability of thin film Cu(In,Ga)Se2 (CIGS) as well as Cu2ZnSnSe4 (CZTS) solar cells are described. Results on the temperature dependency of CIGS solar cells are also presented.

In Situ Monitoring of the Accelerated Performance Degradation of Solar Cells and Modules: A Case Study for CuIn,GaSe2 Solar Cells

Two &#39;Combined Stress test with in situ measurement&#39; setups, which allow real-time monitoring of accelerated degradation of solar cells and modules, were designed and constructed. These setups allow the simultaneous use of humidity, temperature, electrical biases, and illumination as independently controlled stress factors. The setups and various experiments executed are presented.

In Situ Überwachung von der beschleunigten Leistungsabfall von Solarzellen und Modulen: eine Fallstudie für Cu (In, Ga) Se2 Solarzellen

The levelized cost of electricity (LCOE) of photovoltaic (PV) systems is determined by, among other factors, the PV module reliability. Better prediction ...

Elektrospinnen von photokatalytischen Elektroden für farbstoffsensibilisierte Solarzellen

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