AJPはEPSRCソフトナノテクノロジープラットフォーム助成金EP/E046215/1から資金提供を受けています。中性子実験は、OffSpec(RB 1110285)を使用する実験時間の割り当てを介してSTFCによって支持された。

1. サンプルの準備
<ol><li>酸素プラズマの厚さ4mmのシリコンウェーハに2を10分間置いてシリコン基板を洗浄します。</li>
	<li>基板上の第1層をスピンコート<ol>
<li>ポリ(3,4-エチレンジオキシチオフェン):ポリ(スチレンヌスルホン酸塩)(PEDOT:PSS)を0.45 μm PTFEフィルタ(PALL)でフィルターします。</li>
		<li>各サンプルに約0.5 mlを使用して、PEDOT:PSS薄膜を2つのクリーン基板上に60秒間回転させて回転させます。</li>
		<li>オーブンで各基板を10分間乾燥させて70°Cで乾燥させます。</li>
	</ol>
</li>
	<li>2 番目のレイヤーのブレンド ソリューションを準備する<ol>
<li>クロロベンゼンに50mg/mlの濃度でポリ(3-ヘキシルチオフェン-2,5-ディジル)(P3HT)を溶解します。</li>
		<li>50mg/mlの濃度でクロロベンゼン中のPCBMの溶液も調製する。</li>
		<li>1:0.7 P3HT:PCBMの割合で2つのソリューションを混合します。</li>
		<li>0.45 μm PTFE フィルターを使用して混合溶液をフィルター処理します。</li>
	</ol>
</li>
	<li>P3HT:PCBM溶液の約100 μlをPEDOT:PSSコーティング基板に堆積させ、2,000 rpmで30秒間回転して第2層を形成します。</li>
	<li>一方のサンプルをキャストとして残し、もう一方のサンプルをオーブンで150°Cで1時間熱的にアニールします。これは、薄膜表面上の大きなPCBM結晶子の成長をもたらす。</li>
</ol>2. 顕微鏡によるサンプル特性評価
<ol><li>光学顕微鏡<ol>
<li>反射モードで動作する光学顕微鏡で40X顕微鏡目的を使用して両方のサンプルの光学顕微鏡画像を撮影し、CCDカメラを使用して画像をキャプチャします。</li>
		<li>ステップ 2.1.1 で使用した同じ倍率で、既知の長さのサンプルのキャリブレーション画像を記録します。</li>
		<li>既知のサイズのサンプルのピクセル数を決定して、画像のピクセル サイズをミクロン単位で計算します。</li>
		<li>このピクセルサイズを使用して、容易に入手可能な顕微鏡ソフトウェアを使用して画像を較正します。校正された光学顕微鏡画像の例を 図1に示す。</li>
	</ol>
</li>
	<li>原子間力顕微鏡<ol>
<li>2つのサンプルの原子間力顕微鏡(AFM)画像を撮ります。</li>
		<li>容易に入手可能なスキャンプローブソフトウェアを使用してデータを分析し、 図1に示したようなラインプロファイルの数値を生成します。</li>
	</ol>
</li>
</ol>3. セルジス実験
<ol><li>適切な参照サンプルを選択して、参照偏光P0を提供し、目的データのサンプルから取得したデータを正規化できるようにします。</li>
	<li>サンプルと参照サンプルを揃える<ol>
<li>3 つのサンプルをすべて配置テーブルに配置します。これは中性子ビームを横切って変換することができるので、各サンプルをビームに順番に配置することができます。</li>
		<li>サンプルテーブルを変換して、P0 参照サンプルをビームに配置します。</li>
		<li>標準の反射配置方法を使用して、P0 参照サンプルを <0.005° の角度精度に合わせます。</li>
		<li>目的のサンプルを中性子ビームに配置し、サンプルテーブルを変換します。</li>
		<li>標準の反射配置方法を使用して、目的のサンプルを 0.005° < の角度精度に合わせます。</li>
		<li>測定対象のすべてのサンプルに対してこの配置プロセスを繰り返します。</li>
	</ol></li>
	<li>SERGIS インストゥルメントを調整してエコー モードになるようにします。<ol>
<li>ISISパルス中性子とミュオンソース(オックスフォードシャー、英国)で専用のオフスペキュラ反射計OffSpecを設定し、2-14 Åの波長を生成します。使用するセットアップの詳細については、こちらをご覧ください10.</li>
		<li>ガイドフィールド配置の一部で電流をスキャンして、機器の各アームの中性子の総景気後退数のバランスを取るように機器を調整します。これは、RFスピンフリッパー間の距離によって定義される、機器の符号化アーム内の磁場の強度と傾斜を設定することによって達成される。</li>
	</ol></li>
	<li>中性子ビームがP0 サンプルに入るようにサンプルテーブルを傾けることで放牧発生率の角度を設定します(この実験の角度は0.3°)。</li>
	<li>飽和問題を防ぐために、直接伝わる中性子ビームが検出器に到達するのをブロックします。</li>
	<li>サンプルの測定<ol>
<li>参照サンプルが再び中性子ビームに入るようにサンプル変換ステージを移動し、参照サンプルの垂直指向線形シンチレータ検出器上の位置の関数として、散乱中性子強度を測定します。分析装置の直前に散乱したビームのスピンを反転させることによって、スピンアップとスピンダウンの両方の向きを測定します。通常、これは約1時間の期間に行われます。これにより、両方の設定の散乱強度と同様に偏光を決定することができます。</li>
		<li>目的のサンプルの最初を測定するようにサンプルステージを翻訳し、再び約1時間の期間の垂直指向線形シンチレータ検出器を使用して位置の関数としてスピンアップとスピンダウンの両方の向きを記録する。</li>
		<li>この測定に関して十分に良好なカウント統計が得られるまで、ステップ3.6.1と3.6.2を繰り返します。通常、これは合計で約8時間/サンプルです。</li>
		<li>測定が必要なその他のサンプルについて、手順 3.6.1 ~3.6.3 を繰り返します。</li>
	</ol></li>
	<li>収集されたデータは、各サンプルのスピンアップとスピンダウンの両方の2D強度マップで構成されています。数式を使用して、2D データセットの各ピクセルの偏光を計算します。 <img alt="" height="51" src="/files/ftp_upload/51129/51129_3.7_equation.png" width="103"> ここでPは偏光であり、Iはアップと私がダウンして、それぞれ測定されたスピンアップとスピンダウン強度です。</li>
	<li>P0 参照サンプルデータを使用して対象サンプルに対して取得したデータ セットを正規化し、式に従って正規化された偏光強度マップを生成します。 <img alt="" height="49" src="/files/ftp_upload/51129/51129_3.8_equation.png" width="116"> ここで P正規化は決定された偏光計算であり、Pサンプル はサンプル偏光値、P0 は P0 参照サンプルを使用して測定された偏光です。</li>
	<li>適切な範囲でのSERGISデータの統合<ol>
<li>SERGIS データ統合の領域(正規化された偏光プロットのピクセル範囲) を選択します。この領域は、フィールドライン積分の不完全性に起因する任意の潜在的な分極不均一性によって所望のSERGIS信号を浸水させないように選択されるべきである。SERGIS信号が統合され得る利用可能なQ空間は、特定のスピンエコー長さの構成での一連の離散Q値に効果的に制限され、Qはモメンタム伝達ベクトルすなわちサンプルと相互作用した後の中性子の勢いの変化である</li>
		<li>正規化された偏光を統合して、既に定義したSERGIS相関関数G(y)を得ることによって2Dデータを削減する 5.厳密にG(y)は、yに垂直な両方のQベクトル上で無限に統合されるべきであるが、実験的な理由から、積分領域はサンプルの地平線上で選択された検出された強度に限定される。</li>
	</ol></li>
	<li>異なる波長の異なる散乱長密度を補うために、データをスピンエコー小角中性子散乱データと同様の方法で処理し、次のようにデータをプロットします。 <img alt="" height="65" src="/files/ftp_upload/51129/51129_3.10_equation.png" width="127"> ここでλはnmのスピンエコー長であり、y=αλ2を用いて容易に計算することができるが、ここでαは、所定の機器設定11に対する較正された定数を用いて定められる定数である。</li>
</ol>

<ol>
	<li>Mezei, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neutron+spin+echo:+A+new+concept+in+polarized+thermal+neutron+techniques.">Neutron spin echo: A new concept in polarized thermal neutron techniques.</a> Zeitschriftf&#252;r Physik A Hadrons Nuclei. 255, 146-160 (1972).</li><li>Falus, P., Vorobiev, A., Krist, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Test+of+a+two-dimensional+neutron+spin+analyzer.">Test of a two-dimensional neutron spin analyzer.</a> Physica B Condens. Matter. Mater. Phys. , 385-386 (2006).</li><li>Ashkar, R., 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=Dynamical+theory+calculations+of+spin-echo+resolved+grazing-incidence+scattering+from+a+diffraction+grating.">Dynamical theory calculations of spin-echo resolved grazing-incidence scattering from a diffraction grating.</a> J. Appl. Crystallogr. 43 (3), 455-465 (2010).</li><li>Ashkar, R., 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=Dynamical+theory:+Application+to+spin-echo+resolved+grazing+incidence+scattering+from+periodic+structures.">Dynamical theory: Application to spin-echo resolved grazing incidence scattering from periodic structures.</a> J. Appl. Phys. 110 (10), (2011).</li><li>Pynn, R., Ashkar, R., Stonaha, P., Washington, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A.L.,Some+recent+results+using+spin+echo+resolved+grazing+incidence+scattering.">A.L.,Some recent results using spin echo resolved grazing incidence scattering.</a> SERGIS). hysica B Condens. Matter. Mater. Phys. 406 (12), 2350-2353 (2011).</li><li>Ashkar, R., 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=Spin-Echo+Resolved+Grazing+Incidence+Scattering+(SERGIS)+at+Pulsed+and+CW+Neutron+Sources.">Spin-Echo Resolved Grazing Incidence Scattering (SERGIS) at Pulsed and CW Neutron Sources.</a> J. Phy. Conf. Ser. 251 (1), (2010).</li><li>Vorobiev, A., 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=Phase+and+microphase+separation+of+polymer+thin+films+dewetted+from+Silicon-A+spin-echo+resolved+grazing+incidence+neutron+scattering+study.">Phase and microphase separation of polymer thin films dewetted from Silicon-A spin-echo resolved grazing incidence neutron scattering study.</a> J. Phys. Chem. B. 115 (19), 5754-5765 (2011).</li><li>Major, 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=A+spin-echo+resolved+grazing+incidence+scattering+setup+for+the+neutron+interrogation+of+buried+nanostructures.">A spin-echo resolved grazing incidence scattering setup for the neutron interrogation of buried nanostructures.</a> Rev. Sci. Instrum. 80 (12), (2009).</li><li>Parnell, A. J., Dalgliesh, R. M., Jones, R. A. L., Dunbar, A. D. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+neutron+spin+echo+resolved+grazing+incidence+scattering+study+of+crystallites+in+organic+photovoltaic+thin+films.">A neutron spin echo resolved grazing incidence scattering study of crystallites in organic photovoltaic thin films.</a> Appl. Phys. Lett. 102, (2013).</li><li>Dalgliesh, R. M., Langridge, S., Plomp, J., De Haan, V. O., Van Well, A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Offspec,+the+ISIS+spin-echo+reflectometer.+hysica+B+Condens..">Offspec, the ISIS spin-echo reflectometer. hysica B Condens..</a> Matter. Mater. Phys. 406 (12), 2346-2349 (2011).</li><li>Krouglov, T., de Schepper, I. M., Bouwman, W. G., Rekveldt, M. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Real-space+interpretation+of+spin-echo+small-angle+neutron+scattering.">Real-space interpretation of spin-echo small-angle neutron scattering.</a> J. Appl. Crystallogr. 36, 117-124 (2003).</li><li>Brady, M. A., Su, G. M., Chabinyc, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+progress+in+the+morphology+of+bulk+heterojunctionphotovoltaics.">Recent progress in the morphology of bulk heterojunctionphotovoltaics.</a> Soft Matter. 7 (23), 11065-11077 (2011).</li><li>Huang, Y. -. C., 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=Study+of+the+effect+of+annealing+process+on+the+performance+of+P3HT/PCBM+photovoltaic+devices+using+scanning-probe+microscopy..">Study of the effect of annealing process on the performance of P3HT/PCBM photovoltaic devices using scanning-probe microscopy..</a> Solar Energy Mater. Solar Cells. 93 (6-7), 888-892 (2009).</li><li>Parnell, A. 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=Depletion+of+PCBM+at+the+Cathode+Interface+in+P3HT/PCBM+Thin+Films+as+Quantified+via+Neutron+Reflectivity+Measurements.">Depletion of PCBM at the Cathode Interface in P3HT/PCBM Thin Films as Quantified via Neutron Reflectivity Measurements.</a> Adv. Mater. 22 (22), 2444-2447 (2010).</li></ol>

著者のロバート・ダルグリーシュは、この実験で使用される機器をホストするISISパルス中性子とムオンソースの従業員です。

図1の顕微鏡データは、P3HT:PCBM薄膜をアニールする前に平らで滑らかであり、熱アニーリング後に、表面に存在する大きな不規則なPCBM結晶が多く、横寸法が約1〜10μmの横に存在することを明確に示しています。これは、フィルムの上面に向かってPCBMの移行と、その後の凝集物が大きな結晶子を形成することに起因する。アニールサンプル中のPCBM結晶子からの散乱に関連する強いS...

SERGIS技術は、薄膜サンプルから他の散乱または顕微鏡技術を使用してアクセスできないユニークな構造情報を生成できることを目的としています。顕微鏡技術は、通常、表面に制限されるか、内部構造を表示するために大幅な変更/サンプル調製を必要とします。反射率などの従来の散乱技術は、薄膜内の深さの関数として埋め込みサンプル構造に関する詳細な情報を提供することができるが、薄膜の平面内の構造を容易に探査することはできない。最終的には、SERGISが薄膜サンプル内に埋もれてもこの横構造をプローブすることが期待されます。ここで示した代表的な結果は、不規則なサンプル特徴からSERGIS信号を観察することができ、測定された信号がサンプルに存在する特徴に関連する特性の長さスケールと相関することができることを示している。
非弾性スピンエコー技術はMezeiらによって開発された。1970年代に1。 それ以来、SERGIS技術(Mezeiららの考えの延長である)は、高度に規則的な回折格子2-6および円形の濡れ解除ポリマー液滴7などの様々なサンプルを用いて実験的に実証されている。Pynnと同僚が、規則的なサンプル3-6,8からの強い散乱をモデル化するために、動的理論が開発されました。この研究は、この種の測定を行う際に考慮されるべき多くの実用的な側面を強調し、小さな多国籍コミュニティ内で絶え間ない対話につながっています。
測定されるサンプルが平らな基板上の薄膜で構成され、中性子を強く散乱する高密度の特徴(30nm〜5 μm)の散乱特徴を含む場合、SERGIS実験から良好な結果が得られる可能性が最も高い。深度の関数としてサンプルをプローブする他の確立された反射技術とは異なり、SERGIS技術は、サンプル表面の平面内の構造をプローブできるという利点を有する。さらに、スピンエコーを使用すると、高い空間またはエネルギー分解能を得るために中性子ビームをしっかりと結ぶ必要がなくなります。これは、ビームを一方向に強く結束する必要があるため、非常にフラックスが制限されている放牧発生ジオメトリに特に関連します。OffSpec装置を使用すると、バルク構造と表面構造の両方で30nmから5μmの長さのスケールをプローブすることが可能です。

<table border="0" cellpadding="0" cellspacing="0" width="605">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Silicon 2 in silicon substrates</td>
			<td style="width:103px;">Prolog</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">4 mm thick polished one side</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Oxygen plasma</td>
			<td style="width:103px;">Diener</td>
			<td style="width:119px;"></td>
			<td>Oxygen plasma cleaning system to clean substrates prior to coating</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate)</td>
			<td style="width:103px;">Ossila</td>
			<td style="width:119px;"></td>
			<td>PEDOT:PSS conductive polymer layer for organic photovoltaic samples</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">0.45 &#956;m PTFE filter</td>
			<td style="width:103px;">Sigma Aldrich</td>
			<td style="width:119px;"></td>
			<td>Filer to remove aggregates from PEDOT:PSS and P3HT solutions</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Chlorobenzene</td>
			<td style="width:103px;">Sigma Aldrich</td>
			<td style="width:119px;"></td>
			<td>Solvent for P3HT</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Poly(3-hexylthiophene-2,5-diyl)</td>
			<td style="width:103px;">Ossila</td>
			<td style="width:119px;"></td>
			<td>P3HT - polymer used in polymer photovoltaics</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Spin Coater</td>
			<td style="width:103px;">Laurell</td>
			<td style="width:119px;"></td>
			<td>Deposition system for making flat thin polymer films</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Vacuum Oven</td>
			<td style="width:103px;">Binder</td>
			<td style="width:119px;"></td>
			<td>Oven fro annealing samples after preparation</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Nikon Eclipse E600 optical microscope</td>
			<td style="width:103px;">Nikon</td>
			<td style="width:119px;"></td>
			<td>Microscope</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Veeco Dimension 3100 AFM</td>
			<td style="width:103px;">Veeco</td>
			<td style="width:119px;"></td>
			<td>AFM</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Tapping mode tips (~275 kHz)</td>
			<td style="width:103px;">Olympus</td>
			<td style="width:119px;"></td>
			<td>AFM tips</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Quartz Disc</td>
			<td style="width:103px;"></td>
			<td style="width:119px;"></td>
			<td>Refrence samples for SERGIS measurement</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Spin Echo off-specular reflectometer</td>
			<td colspan="2">OffSpec at the ISIS Pulsed Neutron and Muon Source (Oxfordshire, UK)</td>
			<td>Produces pulsed neutrons 2-14 &#197;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Neutron Detector</td>
			<td style="width:103px;">Offspec</td>
			<td style="width:119px;"></td>
			<td>vertically oriented linear scintillator detector</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">RF spin flippers</td>
			<td style="width:103px;">Offspec</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Magnetic Field Guides</td>
			<td style="width:103px;">Offspec</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Data Manipulation Software</td>
			<td style="width:103px;">Mantid</td>
			<td style="width:119px;"></td>
			<td><a href="http://www.mantidproject.org/Main_Page">http://www.mantidproject.org/Main_Page</a></td>
		</tr>
	</tbody>
</table>

using neutron spin echo resolved grazing incidence scattering to investigate organic solar cell materials

スピンエコーは、不規則な形状の結晶子に関連する長さスケールを探査するために、放牧発生散乱(SERGIS)技術を解決した。中性子は磁場の2つの明確に定義された領域を通過する。サンプルの前と後の1つ。2つの磁場領域は反対の極性を有し、両方の領域を通過する中性子が摂動されることなく、反対方向に同じ数の歳座を受けるよう調整されている。この場合、第2のアームの中性子の後ずは第1のアームを「エコー」すると言われ、ビームの元の偏光は保持される。中性子がサンプルと相互作用し、弾性に散乱する場合、第2の腕を通る経路は最初のアームと同じではなく、元の偏光は回復されません。中性子ビームの脱分極は非常に小さい角度(<50 μrad)で非常に敏感なプローブですが、それでも高強度で発散ビームを使用することができます。試料から反射したビームの偏光の減少は、基準試料からのものと比較して、試料内の構造に直接関係し得る。
中性子反射測定で観測された散乱と比較すると、SERGIS信号は弱いことが多く、調査中のサンプル内の面内構造が希薄、無秩序、サイズが小さく、多分散性または中性子散乱コントラストが低い場合には観察される可能性は低い。したがって、測定対象のサンプルが平らな基板上の薄膜で構成され、中性子を強く散乱させる、または特徴が格子上に配置される中程度の大きさの特徴(30nm〜5μm)の高密度を含む散乱特徴を含む場合、SERGIS技術を用いて良い結果が得られる可能性が最も高い。SERGIS技術の利点は、試料の平面内の構造をプローブできることである。

ここで提示した[6,6]フェニル-C61-酪酸メチルエステル(PCBM)およびポリ(3-ヘキシルチオフェン-2,5-diyl)(P3HT)のサンプルの代表的な結果は、有機光変電細胞12,13のバルクヘテロ接合材料としての応用が広く行われているため、重要な関心を示している。通常、有機光起電デバイスの製造中に、P3HT:PCBMブレンド溶液は、ポリ(3,4-エチレンジオキシチオフェン):pオリー(スチレンスルホン酸塩)(PEDOT...

Watch this Scientific Journal Video about Using Neutron Spin Echo Resolved Grazing Incidence Scattering to Investigate Organic Solar Cell Materials at JoVE.com

Using Neutron Spin Echo Resolved Grazing Incidence Scattering to Investigate Organic Solar Cell Materials

不定期サンプルで長さスケールを探査する中性子散乱技術として、スピンエコーが分解した放牧発生率散乱(SERGIS)を利用する進歩が見られました。[6,6]フェニル-C61-酪酸メチルエステルの結晶子は、SERGIS技術を用いてプローブされ、その結果は光学的・原子間力顕微鏡で確認された。

中性子スピンエコーを使用して放牧発生率散乱を解決し、有機太陽電池材料を調査する

The spin echo resolved grazing incidence scattering (SERGIS) technique has been used to probe the length-scales associated with irregularly shaped ...

using-neutron-spin-echo-resolved-grazing-incidence-scattering-to

Research

JoVE Journal

Engineering

6.5K ビュー.  University of Sheffield. 不定期サンプルで長さスケールを探査する中性子散乱技術として、スピンエコーが分解した放牧発生率散乱(SERGIS)を利用する進歩が見られました。[6,6]フェニル-C61-酪酸メチルエステルの結晶子は、SERGIS技術を用いてプローブされ、その結果は光学的・原子間力顕微鏡で確認された。

ビデオ: Using Neutron Spin Echo Resolved Grazing Incidence Scattering to Investigate Organic Solar Cell Materials

Angle-resolved Photoemission Spectroscopy At Ultra-low Temperatures

The physical properties of a material are defined by its electronic structure. Electrons in solids are characterized by energy (&omega;) and momentum (k) and the probability to find them in a particular state with given &omega; and k is described by the spectral function A(k, &omega;). This function can be directly measured in an experiment based on the well-known photoelectric effect, for the explanation of which Albert Einstein received the Nobel Prize back in 1921. In the photoelectric effect the light shone on a surface ejects electrons from the material. According to Einstein, energy conservation allows one to determine the energy of an electron inside the sample, provided the energy of the light photon and kinetic energy of the outgoing photoelectron are known. Momentum conservation makes it also possible to estimate k relating it to the momentum of the photoelectron by measuring the angle at which the photoelectron left the surface. The modern version of this technique is called Angle-Resolved Photoemission Spectroscopy (ARPES) and exploits both conservation laws in order to determine the electronic structure, i.e. energy and momentum of electrons inside the solid. In order to resolve the details crucial for understanding the topical problems of condensed matter physics, three quantities need to be minimized: uncertainty* in photon energy, uncertainty in kinetic energy of photoelectrons and temperature of the sample.
In our approach we combine three recent achievements in the field of synchrotron radiation, surface science and cryogenics. We use synchrotron radiation with tunable photon energy contributing an uncertainty of the order of 1 meV, an electron energy analyzer which detects the kinetic energies with a precision of the order of 1 meV and a He3 cryostat which allows us to keep the temperature of the sample below 1 K. We discuss the exemplary results obtained on single crystals of Sr2RuO4 and some other materials. The electronic structure of this material can be determined with an unprecedented clarity.

The overall goal of this method is to determine the low-energy electronic structure of solids at ultra-low temperatures using Angle-Resolved Photoemission Spectroscopy with synchrotron radiation.

超低温での角度分解光電子分光

The physical properties of a material are defined by its  electronic structure. Electrons in solids are characterized by energy (&omega;)  and momentum ...

工学

Concurrent Quantitative Conductivity and Mechanical Properties Measurements of Organic Photovoltaic Materials using AFM

Organic photovoltaic (OPV) materials are inherently inhomogeneous at the nanometer scale. Nanoscale inhomogeneity of OPV materials affects performance of photovoltaic devices. Thus, understanding of spatial variations in composition as well as electrical properties of OPV materials is of paramount importance for moving PV technology forward.1,2 In this paper, we describe a protocol for quantitative measurements of electrical and mechanical properties of OPV materials with sub-100 nm resolution. Currently, materials properties measurements performed using commercially available AFM-based techniques (PeakForce, conductive AFM) generally provide only qualitative information. The values for resistance as well as Young's modulus measured using our method on the prototypical ITO/PEDOT:PSS/P3HT:PC61BM system correspond well with literature data. The P3HT:PC61BM blend separates onto PC61BM-rich and P3HT-rich domains. Mechanical properties of PC61BM-rich and P3HT-rich domains are different, which allows for domain attribution on the surface of the film. Importantly, combining mechanical and electrical data allows for correlation of the domain structure on the surface of the film with electrical properties variation measured through the thickness of the film.

Organic photovoltaic (OPV) materials are inherently inhomogeneous at the nanometer scale. Nanoscale inhomogeneity of OPV materials affects performance of photovoltaic devices. In this paper, we describe a protocol for quantitative measurements of electrical and mechanical properties of OPV materials with sub-100 nm resolution.

同時定量伝導率およびAFMを用いた有機太陽電池材料の機械的特性の測定

Organic photovoltaic  (OPV) materials are inherently inhomogeneous at the nanometer scale. Nanoscale  inhomogeneity of OPV materials affects performance ...

Measuring Material Microstructure Under Flow Using 1-2 Plane Flow-Small Angle Neutron Scattering

A new small-angle neutron scattering (SANS) sample environment optimized for studying the microstructure of complex fluids under simple shear flow is presented. The SANS shear cell consists of a concentric cylinder Couette geometry that is sealed and rotating about a horizontal axis so that the vorticity direction of the flow field is aligned with the neutron beam enabling scattering from the 1-2 plane of shear (velocity-velocity gradient, respectively). This approach is an advance over previous shear cell sample environments as there is a strong coupling between the bulk rheology and microstructural features in the 1-2 plane of shear. Flow-instabilities, such as shear banding, can also be studied by spatially resolved measurements. This is accomplished in this sample environment by using a narrow aperture for the neutron beam and scanning along the velocity gradient direction. Time resolved experiments, such as flow start-ups and large amplitude oscillatory shear flow are also possible by synchronization of the shear motion and time-resolved detection of scattered neutrons. Representative results using the methods outlined here demonstrate the useful nature of spatial resolution for measuring the microstructure of a wormlike micelle solution that exhibits shear banding, a phenomenon that can only be investigated by resolving the structure along the velocity gradient direction. Finally, potential improvements to the current design are discussed along with suggestions for supplementary experiments as motivation for future experiments on a broad range of complex fluids in a variety of shear motions.

A shear cell is developed for small-angle neutron scattering measurements in the velocity-velocity gradient plane of shear and is used to characterize complex fluids. Spatially resolved measurements in the velocity gradient direction are possible for studying shear-banding materials. Applications include investigations of colloidal dispersions, polymer solutions, and self-assembled structures.

1〜2平面フロー小角中性子散乱を用いた材料の微細構造の下で流量を測定

A new small-angle neutron scattering (SANS) sample environment optimized for studying the microstructure of complex fluids under simple shear flow is ...

In Situ Neutron Powder Diffraction Using Custom-made Lithium-ion Batteries

Li-ion batteries are widely used in portable electronic devices and are considered as promising candidates for higher-energy applications such as electric vehicles.1,2 However, many challenges, such as energy density and battery lifetimes, need to be overcome before this particular battery technology can be widely implemented in such applications.3 This research is challenging, and we outline a method to address these challenges using in situ NPD to probe the crystal structure of electrodes undergoing electrochemical cycling (charge/discharge) in a battery. NPD data help determine the underlying structural mechanism responsible for a range of electrode properties, and this information can direct the development of better electrodes and batteries.
We briefly review six types of battery designs custom-made for NPD experiments and detail the method to construct the &#8216;roll-over&#8217; cell that we have successfully used on the high-intensity NPD instrument, WOMBAT, at the Australian Nuclear Science and Technology Organisation (ANSTO). The design considerations and materials used for cell construction are discussed in conjunction with aspects of the actual in situ NPD experiment and initial directions are presented on how to analyze such complex in situ data.

In Situ Neutron Powder Diffraction Using Custom-made Lithium-ion Batteries

We describe the design and construction of an electrochemical cell for the examination of electrode materials using in situ neutron powder diffraction (NPD). We briefly comment on alternate in situ NPD cell designs and discuss methods for the analysis of the corresponding in situ NPD data produced using this cell.

その場中性子粉末回折ではカスタムメイドのリチウムイオン電池を使用して、

Li-ion batteries are widely used in portable electronic devices and are considered as promising candidates for higher-energy applications such as electric ...

Using Synchrotron Radiation Microtomography to Investigate Multi-scale Three-dimensional Microelectronic Packages

Synchrotron radiation micro-tomography (SR&#181;T) is a non-destructive three-dimensional (3D) imaging technique that offers high flux for fast data acquisition times with high spatial resolution. In the electronics industry there is serious interest in performing failure analysis on 3D microelectronic packages, many which contain multiple levels of high-density interconnections. Often in tomography there is a trade-off between image resolution and the volume of a sample that can be imaged. This inverse relationship limits the usefulness of conventional computed tomography (CT) systems since a microelectronic package is often large in cross sectional area 100-3,600 mm2, but has important features on the micron scale. The micro-tomography beamline at the Advanced Light Source (ALS), in Berkeley, CA USA, has a setup which is adaptable and can be tailored to a sample&#39;s properties, i.e., density, thickness, etc., with a maximum allowable cross-section of 36 x 36 mm. This setup also has the option of being either monochromatic in the energy range ~7-43 keV or operating with maximum flux in white light mode using a polychromatic beam. Presented here are details of the experimental steps taken to image an entire 16 x 16 mm system within a package, in order to obtain 3D images of the system with a spatial resolution of 8.7 &#181;m all within a scan time of less than 3 min. Also shown are results from packages scanned in different orientations and a sectioned package for higher resolution imaging. In contrast a conventional CT system would take hours to record data with potentially poorer resolution. Indeed, the ratio of field-of-view to throughput time is much higher when using the synchrotron radiation tomography setup. The description below of the experimental setup can be implemented and adapted for use with many other multi-materials.

For this study synchrotron radiation micro-tomography, a non-destructive three-dimensional imaging technique, is employed to investigate an entire microelectronic package with a cross-sectional area of 16 x 16 mm. Due to the synchrotron&#39;s high flux and brightness the sample was imaged in just 3 min&#160;with an 8.7 &#181;m spatial resolution.

マルチスケール三次元マイクロエレクト​​ロニクスパッケージを調査するために放射光マイクロトモグラフィーを用いて、

Synchrotron radiation micro-tomography (SR&#181;T) is a non-destructive three-dimensional (3D) imaging technique that offers high flux for fast data ...

Recombination Dynamics in Thin-film Photovoltaic Materials via Time-resolved Microwave Conductivity

A method for investigating recombination dynamics of photo-induced charge carriers in thin film semiconductors, specifically in photovoltaic materials such as organo-lead halide perovskites is presented. The perovskite film thickness and absorption coefficient are initially characterized by profilometry and UV-VIS absorption spectroscopy. Calibration of both laser power and cavity sensitivity is described in detail. A protocol for performing Flash-photolysis Time Resolved Microwave Conductivity (TRMC) experiments, a non-contact method of determining the conductivity of a material, is presented. A process for identifying the real and imaginary components of the complex conductivity by performing TRMC as a function of microwave frequency is given. Charge carrier dynamics are determined under different excitation regimes (including both power and wavelength). Techniques for distinguishing between direct and trap-mediated decay processes are presented and discussed. Results are modelled and interpreted with reference to a general kinetic model of photoinduced charge carriers in a semiconductor. The techniques described are applicable to a wide range of optoelectronic materials, including organic and inorganic photovoltaic materials, nanoparticles, and conducting/semiconducting thin films.

A Time Resolved Microwave Conductivity technique for investigating direct and trap-mediated recombination dynamics and determining carrier mobilities of thin film semiconductors is presented here.

時間分解マイクロ波伝導を介して、薄膜太陽電池材料での再結合ダイナミクス

A method for investigating recombination dynamics of photo-induced charge carriers in thin film semiconductors, specifically in photovoltaic materials ...

Electrospinning of Photocatalytic Electrodes for Dye-sensitized Solar Cells

This work demonstrates a protocol to fabricate a fiber-based photoanode for dye-sensitized solar cells, consisting of a light-scattering layer made of electrospun titanium dioxide nanofibers (TiO2-NFs) on top of a blocking layer made of commercially available titanium dioxide nanoparticles (TiO2-NPs). This is achieved by first electrospinning a solution of titanium (IV) butoxide, polyvinylpyrrolidone (PVP), and glacial acetic acid in ethanol to obtain composite PVP/TiO2 nanofibers. These are then calcined at 500 &#176;C to remove the PVP and to obtain pure anatase-phase titania nanofibers. This material is characterized using scanning electron microscopy (SEM) and powder X-ray diffraction (XRD). The photoanode is prepared by first creating a blocking layer through the deposition of a TiO2-NPs/terpineol slurry on a fluorine-doped tin oxide (FTO) glass slide using doctor blading techniques. A subsequent thermal treatment is performed at 500 &#176;C. Then, the light-scattering layer is formed by depositing a TiO2-NFs/terpineol slurry on the same slide, using the same technique, and calcinating again at 500 &#176;C. The performance of the photoanode is tested by fabricating a dye-sensitized solar cell and measuring its efficiency through J-V curves under a range of incident light densities, from 0.25-1 Sun.

The overall goal of this project was to use electrospinning to fabricate a photoanode with improved performance for dye-sensitized solar cells.

色素増感太陽電池用光触媒電極のエレクトロスピニング

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

Dielectric RheoSANS &#8212; Simultaneous Interrogation of Impedance, Rheology and Small Angle Neutron Scattering of Complex Fluids

A procedure for the operation of a new dielectric RheoSANS instrument capable of simultaneous interrogation of the electrical, mechanical and microstructural properties of complex fluids is presented. The instrument consists of a Couette geometry contained within a modified forced convection oven mounted on a commercial rheometer. This instrument is available for use on the small angle neutron scattering (SANS) beamlines at the National Institute of Standards and Technology (NIST) Center for Neutron Research (NCNR). The Couette geometry is machined to be transparent to neutrons and provides for measurement of the electrical properties and microstructural properties of a sample confined between titanium cylinders while the sample undergoes arbitrary deformation. Synchronization of these measurements is enabled through the use of a customizable program that monitors and controls the execution of predetermined experimental protocols. Described here is a protocol to perform a flow sweep experiment where the shear rate is logarithmically stepped from a maximum value to a minimum value holding at each step for a specified period of time while frequency dependent dielectric measurements are made. Representative results are shown from a sample consisting of a gel composed of carbon black aggregates dispersed in propylene carbonate. As the gel undergoes steady shear, the carbon black network is mechanically deformed, which causes an initial decrease in conductivity associated with the breaking of bonds comprising the carbon black network. However, at higher shear rates, the conductivity recovers associated with the onset of shear thickening. Overall, these results demonstrate the utility of the simultaneous measurement of the rheo-electro-microstructural properties of these suspensions using the dielectric RheoSANS geometry.

Dielectric RheoSANS &amp;#8212; Simultaneous Interrogation of Impedance, Rheology and Small Angle Neutron Scattering of Complex Fluids

Here, we present a procedure for the measurement of simultaneous impedance, rheology and neutron scattering from soft matter materials under shear flow.

誘電RheoSANS  - インピーダンス、レオロジー及び複雑流体の小角中性子散乱の同時尋問

A procedure for the operation of a new dielectric RheoSANS instrument capable of simultaneous interrogation of the electrical, mechanical and ...

Simultaneous Multi-surface Anodizations and Stair-like Reverse Biases Detachment of Anodic Aluminum Oxides in Sulfuric and Oxalic Acid Electrolyte

After reporting on the two-step anodization, nanoporous anodic aluminum oxides (AAOs) have been widely utilized in the versatile fields of fundamental sciences and industrial applications owing to their periodic arrangement of nanopores with relatively high aspect ratio. However, the techniques reported so far, which could be only valid for mono-surface anodization, show critical disadvantages, i.e., time-consuming as well as complicated procedures, requiring toxic chemicals, and wasting valuable natural resources. In this paper, we demonstrate a facile, efficient, and environmentally clean method to fabricate nanoporous AAOs in sulfuric and oxalic acid electrolytes, which can overcome the limitations that result from conventional AAO fabricating methods. First, plural AAOs are produced at one time through simultaneous multi-surfaces anodization (SMSA), indicating mass-producibility of the AAOs with comparable qualities. Second, those AAOs can be separated from the aluminum (Al) substrate by applying stair-like reverse biases (SRBs) in the same electrolyte used for the SMSAs, implying simplicity and green technological characteristics. Finally, a unit sequence consisting of the SMSAs sequentially combined with SRBs-based detachment can be applied repeatedly to the same Al substrate, which reinforces the advantages of this strategy and also guarantees the efficient usage of natural resources.

A protocol for fabricating nanoporous anodic aluminum oxides via simultaneous multi-surfaces anodization followed by stair-like reverse biases detachments is presented. It can be applied repeatedly to the same aluminum substrate, exhibiting a facile, high-yield, and environmentally clean strategy.

同時マルチ表面 Anodizations、階段のような逆バイアスで硫酸陽極酸化アルミニウムとシュウ酸電解質の剥離

After reporting on the two-step anodization, nanoporous anodic aluminum oxides (AAOs) have been widely utilized in the versatile fields of fundamental ...

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser

The goal of this protocol is to present how to perform spin- and angle-resolved photoemission spectroscopy combined with polarization-variable 7-eV laser (laser-SARPES), and demonstrate a power of this technique for studying solid state physics. Laser-SARPES achieves two great capabilities. Firstly, by examining orbital selection rule of linearly polarized lasers, orbital selective excitation can be carried out in SAPRES experiment. Secondly, the technique can show full information of a variation of the spin quantum axis as a function of the light polarization. To demonstrate the power of the collaboration of these capabilities in laser-SARPES, we apply this technique for the investigations of spin-orbit coupled surface states of Bi2Se3. This technique affords to decompose spin and orbital components from the spin-orbit coupled wavefunctions. Moreover, as a representative advantage of using the direct spin detection collaborated with the polarization-variable laser, the technique unambiguously visualizes the light polarization dependence of the spin quantum axis in three-dimension. Laser-SARPES dramatically increases a capability of photoemission technique.

Here, we combine polarization-variable 7-eV laser with spin- and angle-resolved photoemission technique to visualize the spin-orbital coupling effect in solid states.

偏波可変レーザーと組み合わせてスピン角度分解光電子分光の実験法

The goal of this protocol is to present how to perform spin- and angle-resolved photoemission spectroscopy combined with polarization-variable 7-eV laser ...