Support for this work was provided by DOE STTR grant DE-SC0003664 on Parallel Tandem Organic Solar Cells with Carbon Nanotube Sheet Interlayers and Welch Foundation grant AT-1617. The authors thank J. Bykova for providing CNT forests and A. R. Howard, K. Meilczarek, and J. Velten for technical assistance and useful discussions.

1.インジウムスズ酸化物（ITO）のパターニングとクリーニング注：使用15Ω/□のITOガラス、スピンコートし、フォトリソグラフィーに適し大きさにITOガラスを購入するか、カット。これは、できるだけ大きなガラス片に、手順1.1から1.7までを実行し、より小型のデバイスにそれを切断することが最も効率的である。また、それは1.1から1.7までは、ITO側を上にして配向させるためのITOガラスを必要とするステップに注意してください。これはマルチメータの抵抗設定で容易に確認することができる。 <ol><li> 1分間の3,000rpmでの速度でITOガラスのITO側へS1813ポジ型フォトレジストのスピンコートを1ml。ガラスの大きなピース用のレジストより使用全体ガラスがコーティングされていることを確認し、スピンコーターを開始する前に気泡を除去。 </li><li> 1分間115℃でホットプレート上で、コーティングされたガラスレジストアニールする。 </li><li>サンプルおよびコンタクトアライナーの上にフォトマスクをロードします。 </li><li>アプロ用のフォトレジストコーティングされたITOガラスを公開priate時間。露光時間は約10秒であるが、UVランプ強度、レジストの種類、厚さに基づいて、この時間を変化させる。 </li><li> MF311現像液中の紫外線露光した基板を開発する。スピンプロセッサの自動化されたプロセスは、最良かつ最も再現性のある結果が生成されますが、続くように開発が手動で行うことができます。 <ol><li>現像液中​​で1分間UV-露光した基板を浸し、脱イオン（DI）水中でリンスし、窒素ガンで乾燥した。開発者が迅速に強度を失うので、サンプル間の現像液を交換する、または開発を再利用する際に、代替的開発時間を増やす。 </li></ol></li><li>濃塩酸（HCl）の中にITO基板をエッチングする。これは、HClの濃度に応じて5〜10分かかります。 、DI水中ですすぎ、乾燥、およびマルチメータとのエッチングされた部分の抵抗率をテストします。どの導電性が残っている場合は、より長い時間エッチ。 </li><li>エッチングが完了すると、ページを削除するアセトンでhotoresist。フォトレジストの迅速な除去はオーバーエッチングパターン化されたITOから残留塩酸を妨げることに注意してください。 </li><li>必要に応じて、デバイスのサイズにエッチングされたITOガラス基板を切断する。 </li><li> DI水、アセトン、トルエン、メタノール、そして最後にイソプロピルアルコール - 溶剤の順序で入浴超音波処理装置におけるITO基板を清掃してください。 </li></ol> 2. OPVサブセルの作製<ol><li> PC 61 BMソリューション：P3HTを準備します。 注：最も一貫した結果を得るには、窒素環境でのソリューションを準備します。これは、周囲条件で、この手順に従うことが可能である。 <ol><li>見つけて、2クリーン、〜4ミリリットルのガラスバイアルとそのキャップの質量を書き留め、別からそれらを区別するために油性マジックでそれらをマークします。 </li><li>窒素またはアルゴングローブボックス中で一のバイアル及びフェニルC 61 -酪酸メチルエステル（P約10mgのポリ（3-ヘキシルチオフェン-2,5-ジイル）（P3HT）の約10mgの転送他に、C 61 BM）。 </li><li> P3HTとPC 61 BMの質量を見つけるために、再度バイアルを計量。 </li><li>ソリューション製造プロセスの残りのためのグローブボックスにP3HTとPC 61 BMとのバイアルを転送します。 </li><li>各バイアルに磁気攪拌棒を追加し、45 mg / mlのソリューションを作成するためにそれぞれに十分なクロロベンゼンを追加します。 </li><li>約2時間、または溶質が完全に溶解するまで55℃で磁気撹拌しながらホットプレート上でソリューションを置きます。 </li><li>一緒にP3HTとPC 61 BMソリューションを等量混合し、使用前にさらに1時間混合溶液を攪拌してみましょう。 </li></ol></li><li> PC 71 BMソリューション：PTB7を準備します。 <ol><li>繰り返しますと2.1.4に2.1.1ステップpoly({4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl}) （PTB7）及びフェニル- 7,1 -酪酸メチルエステル（PC 71 BM）の代わりにP3HTとPCの61 BM。 </li><li>クロロベンゼン中のボリューム1,8- diiodooctane（DIO）により、3％の混合物を作る。このミックスはDIO-CBと呼ばれている。 </li><li> 40 mg / mlの溶液を持っているPC 71 BMバイアルに12 mg / mlの溶液と十分にDIO-CBを持つようにPTB7バイアルに十分DIO-CBを追加し、各バイアルに磁気撹拌棒を加え、。 </li><li>これらの溶液は二日間70℃でホットプレート上で撹拌してみよう。 </li><li> 1.5へのPC 71 1のBMへPTB7の重量比で溶液を混合。 </li><li> 70℃でさらに1時間混合溶液を攪拌は、使用前にしよう。 </li></ol></li><li>フィルタポリ（3,4-エチレンジオキシチオフェン）：ポリ（スチレンスルホン酸）（PEDOT：PSS）を0.45μm孔径のナイロンフィルターを通して。この手順は、P VP AI4083を使用しています注意してください。 </li><li>スピンコート活性層。 <ol><li> 5分間UVオゾンクリーナーに、洗浄したITO基板、ITO側を上にして置きます。 </li><li>スピンコートフィルターPEDOT120μlの：PSSを扱わUV-オゾン上に、ITO-ガラス基板をパターニングし1分間3,000 rpmでの。これは30nmの厚さの層が得られるはずです。 </li><li> PEDOTをアニール：180℃で5分間PSSコーティングされたITO基板を。 </li><li> PEDOT上にPC 61 BMソリューション：混合P3HTの70μlのコートをスピンコーティングされたPSS ITO基板1分間約1,000 rpmで。厚さ200nmの活性層を堆積させるために、必要に応じて速度を変化させる。 </li><li> P3HTをアニール：PC 61 BMがコーティングされた基材を170℃で5分間。結果は、最適なアニーリング温度により異なる可能性があります。 </li><li>混合PTB7の70μlのコートをスピン：PEDOT上にPC 71 BMソリューション：PSSコーティングされたITO基板1分間約700rpmで。厚さ100nmの活性層を堆積させるために、必要に応じて速度を変化させる。 </li><li>残留DIOを除去するために高真空（&lt;×10 2 -6トル）チャンバー内に、PC 71 BMコーティングされた基材：PTB7をロードします。典型的には、チャンバのO / Nの中のサンプルを残す。 </li></ol></li></ol> 3.タンデムデバイスを製造 &lt;オール&gt; <li>ラミネートCNT電極。 <ol><li>タンデムデバイスを作るために半分にPTB7とP3HTの基板をカットします。専門的なITOパターンは、このステップを必要としない。 ITOパターンは、少なくとも二つの平行ITOが離れて、​​他から1ミリメートルに一方の縁から延びる電極が必要です。 </li><li>第一のガラスの縁部からポリマー及びPEDOTを拭き取ることによってPTB7およびP3HTコーティングされた基材を準備し、 図1の第1のパネルに見られるように、共通電極として使用されるITOストリップを露光する。 </li><li> PTB7とP3HTの電極の上にCNTの共通電極を積層。デバイス上のろ紙のCNT側に配置軽く押し、その後離れてろ紙を剥離することによりSWCNT膜を適用する。これは、 図1の第2のパネルに示されている。 </li><li>メトキシ-ノナフルオロブタン（C 4 F 9 OCH 3）（HFE）を適用することによって、小さな天羽にCNTを被覆することによって表面上にCNT電極を高密度化液体のNTと、それはオフに乾燥させる。 </li><li> 図1の第3のパネルに示すように、ゲート電極を持つことになります、ITOの上部とガラス上のポリマーとCNTを拭き取る。カミソリの刃でゲートリークを防止するために、ガラスからの全てのポリマーを削除します。 </li><li> PTB7とP3HTコーティングされた基材の清掃領域にCNTゲート電極を積層。かみそりの刃でMWCNTの森の端から引いてMWCNTを積層し、シートは、いくつかのキャピラリーチューブの間を自由に放置。デバイス上にCNTを積層する自立型シートを介してデバイスを渡します。共通電極上に置かように、ゲート電極は、層の2〜3倍の数を持っている必要があります。 </li><li> HFEゲート電極を高密度化。 </li></ol></li><li> 1のCNT電極の両方の上に、（2-メトキシエチル）アンモニウムテトラフルオロボDEME-BF 4 -イオン液体の小滴（≈10μl）を置き、N、N- -Diethyl- Nは、Nをメチル-基質の。 </li><li>慎重に各-互いの上に共通電極およびゲート電極とイオン液体との基板の上にイオン液体ずに基板を配置します。これは、 図1の最後のパネルに示されている。 </li><li>アクティブ領域上の電極サイズよりも小さい開口サイズを持つフォトマスクを配置します。所定の位置にマスクを保持するだけでなく、テスト中に一緒にデバイスを保持するために、小さなクリップを使用する。 </li></ol> 4. [デバイスを測定します<ol><li>測定グローブボックスにデバイスを移す。 </li><li>電気的な接続を行います。 <ol><li>共通電極とグランドなどの共通ゲート電極との間にゲート電源を接続します。 </li><li>陽極または両方の陽極のどちらかの選択を可能にするスイッチに接続されたワイヤに2枚のITOアノードを接続します。 </li><li>ソースメジャーユニットの入力にスイッチの出力に接続します。 </li><li>ソースMEAのグランドを接続共通電極UREユニット。 </li></ol></li><li> V ゲート昇順ための次のステップを繰り返すことで、デバイスのI-V特性を測定します。 <ol><li> = 0 V V ゲートから0.25 Vの刻みで= 2 V V ゲートに始まり、次の値にV ゲートを設定</li><li>ゲート電流が安定するまで5分待つか。理想的には、ゲート電流はナノアンペアの10sのまわり安定させる必要があります。 </li><li>両方のサブ·セルにスイッチを設定してください。 </li><li>ランプのシャッターを開きます。 </li><li>約100の増分以上に1ボルトに-1ボルトからソースメジャーユニットの電圧スイープを実行します。 </li><li> -1ボルトに1ボルトの電圧スイープを実行します。 </li><li>ランプのシャッターを閉じます。 </li><li>再び電圧スイープを実行します。 </li><li>フロントサブセルにスイッチを設定してください。 </li><li>繰り返して4.3.8に4.3.4を繰り返します。 </li><li>バックサブセルにスイッチを設定します。 </li><li>繰り返して4.3.8に4.3.4を繰り返します。 </li></ol></li><li>デバイスパラメータを計算します。 &lt;オール&gt; <li>サブセルの両端の電圧が0Vであるとき、デバイスによって生成される電流を求めることによって、各V ゲートにおける各サブセルの短絡電流（J SC）を見つける</li><li>サブセルを流れる電流が0Aであるときに、デバイスによって生成される電圧を求めることにより、各V ゲートにおける各サブセルの開回路電圧（V OC）を見つける</li><li>各電流値で、各電圧値を乗算し、最大（最も負）の値を選択することにより、太陽電池から最大電力出力を検索します。これは1つが、光生成電流と負の電流を測定することを前提としています。 </li><li>入力光パワー、最大パワーを分割することにより電力変換効率（η）を見つける。 </li><li> J SCとV OCの積で最大電力で除して充填率（FF）を見つける。 </li></ol></li></ol>

<ol>
	<li>He, Z., Zhong, C., Su, S., Xu, M., Wu, H., Cao, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enhanced+power-conversion+efficiency+in+polymer+solar+cells+using+an+inverted+device+structure.">Enhanced power-conversion efficiency in polymer solar cells using an inverted device structure.</a> Nature Photonics. 6, 591-595 (2012).</li><li>Yuan, Y., Huang, J., Li, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intermediate+layers+in+tandem+organic+solar+cells.">Intermediate layers in tandem organic solar cells.</a> Green. 1 (1), 65-80 (2011).</li><li>Kim, J. Y., 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=Efficient+tandem+polymer+solar+cells+fabricated+by+all-solution+processing.">Efficient tandem polymer solar cells fabricated by all-solution processing.</a> Science. 317 (5835), 222-225 (2007).</li><li>Yu, B., Zhu, F., Wang, H., Li, G., Yan, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=All-organic+tunnel+junctions+as+connecting+units+in+tandem+organic+solar+cell.">All-organic tunnel junctions as connecting units in tandem organic solar cell.</a> Journal of Applied Physics. 104 (11), (2008).</li><li>Schueppel, 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=Controlled+current+matching+in+small+molecule+organic+tandem+solar+cells+using+doped+spacer+layers.">Controlled current matching in small molecule organic tandem solar cells using doped spacer layers.</a> Journal of Applied Physics. 107 (4), (2010).</li><li>Hiramoto, M., Suezaki, M., Yokoyama, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+thin+gold+interstitial-layer+on+the+photovoltaic+properties+of+tandem+organic+solar+cell.">Effect of thin gold interstitial-layer on the photovoltaic properties of tandem organic solar cell.</a> Chemistry Letters. 19 (3), 327-330 (1990).</li><li>Xue, J., Uchida, S., Rand, B. P., Forrest, S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Asymmetric+tandem+organic+photovoltaic+cells+with+hybrid+planar-mixed+molecular+heterojunctions.">Asymmetric tandem organic photovoltaic cells with hybrid planar-mixed molecular heterojunctions.</a> Applied Physics Letters. 85 (23), 5757 (2004).</li><li>Tanaka, S., 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=Monolithic+parallel+tandem+organic+photovoltaic+cell+with+transparent+carbon+nanotube+interlayer.">Monolithic parallel tandem organic photovoltaic cell with transparent carbon nanotube interlayer.</a> Applied Physics Letters. 94 (11), (2009).</li><li>Mielczarek, K., Cook, A., Kuznetsov, A., Zakhidov, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=OPV+Tandems+with+CNTS:+Why+Are+Parallel+Connections+Better+Than+Series+Connections.">OPV Tandems with CNTS: Why Are Parallel Connections Better Than Series Connections.</a> Low-Dimensional Functional Materials. , 179-204 (2013).</li><li>Kim, J. Y., 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=Efficient+tandem+polymer+solar+cells+fabricated+by+all-solution+processing.">Efficient tandem polymer solar cells fabricated by all-solution processing.</a> Science. 317 (5835), 222-225 (2007).</li><li>Kuznetsov, 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=.">.</a> Physics of electron field emission by self-assembled carbon nanotube arrays. , (2008).</li><li>Kuznetzov, A. A., Lee, S. B., Zhang, M., Baughman, R. H., Zakhidov, 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=Electron+field+emission+from+transparent+multiwalled+carbon+nanotube+sheets+for+inverted+field+emission+displays.">Electron field emission from transparent multiwalled carbon nanotube sheets for inverted field emission displays.</a> Carbon. 48 (1), 41-46 (2010).</li><li>Zakhidov, A. A., Suh, D. -. S., 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=Electrochemically+Tuned+Properties+for+Electrolyte-Free+Carbon+Nanotube+Sheets.">Electrochemically Tuned Properties for Electrolyte-Free Carbon Nanotube Sheets.</a> Advanced Functional Materials. 19 (14), 2266-2272 (2009).</li><li>Cook, A., Yuen, J. D., Zakhidov, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ion-Reconfigurable+photovoltaic+cells,+hybrid+tandems+and+photodetectors+with+CNT+ionic+gate.">Ion-Reconfigurable photovoltaic cells, hybrid tandems and photodetectors with CNT ionic gate.</a> US Patent Application. 61, (2012).</li><li>Cook, A. B., Yuen, J. D., Zakhidov, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrochemically+gated+organic+photovoltaic+with+tunable+carbon+nanotube+cathodes.">Electrochemically gated organic photovoltaic with tunable carbon nanotube cathodes.</a> Applied Physics Letters. 103 (16), (2013).</li><li>Wadhwa, P., Liu, B., McCarthy, M. A., Wu, Z., Rinzler, A. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electronic+Junction+Control+in+a+Nanotube-Semiconductor+Schottky+Junction+Solar+Cell.">Electronic Junction Control in a Nanotube-Semiconductor Schottky Junction Solar Cell.</a> Nanoletters. 10 (12), 5001-5005 (2010).</li></ol>

The authors have nothing to disclose.

パラレルタンデム太陽電池を設計するときの結果は、いくつかの考慮事項を強調表示します。注目すべきことに、サブセルの場合つは、不十分にマイナス影響を受けたタンデム性能を行っている。結果は、2つの主要な効果があることを示している。一つのサブセルが短絡すると、 例えば 、ミック挙動を示し、FF Tが悪いサブセルのFFよりも高くないであろう。 J T SC...

ポリマー半導体は、高い吸収性、優れた輸送特性、柔軟性、および温度感受性基材との相溶性に主要な有機光起電（OPV）材料である。 OPVデバイスの電力変換効率、η、それらますます実行可能なエネルギー技術作り、9.1％1という高い単一細胞効率で、過去数年間で大幅に跳ね上がっている。 ηの向上にもかかわらず、デバイスの薄最適な活性層の厚さは、光の吸収を制限し、信頼性のある製造を妨げる。さらに、各ポリマーの光吸収のスペクトル幅は、無機材料と比較して制限される。分光感度の異なるペアリングポリマーは、タンデム·アーキテクチャ2必要な技術革新を作り、これらの問題を回避します。 直列タンデムデバイスでは、最も一般的なタンデム·アーキテクチャである。この設計では、電子輸送materiら、任意の金属結合層、及び正孔輸送層は、サブセルと呼ばれる二つの独立した光活性層を接続する。直列構成でサブセルをリ​​ンクする結合装置の開回路電圧を増加させる。いくつかのグループは、縮退ドープ輸送層3との成功があった-図5は 、より多くのグループが、層間6,7で正孔と電子の再結合を支援するために、金または銀の粒子を使用した。 対照的に、並列タンデムの2つの活性層を接合する導電性の高い電極、陽極または陰極のいずれかを必要とする。中間層は、金属粒子を含有する連タンデム中間層を制限し、さらにより薄いので、連続的な金属電極の並列タンデム中間ため、これは非常に透明でなければならない。カーボンナノチューブ（CNT）シートは、金属層よりも高い透明性を示す。ナノテク研究所ので、島根大学と共同で、int型を持つモノリシック、パラレルタンデムデバイス8における層間電極として使用することの概念をroduced。 以前の努力は、層間陽極8,9として機能CNTシートを備えたモノリシック、パラレル、タンデムOPVデバイスを特色にした。これらのメソッドは、後に層を堆積する際に、一方または両方の細胞または損傷前の層の短絡を避けるために特別な注意が必要です。この論文で説明されている新しいメソッドは、2つの単電池のポリマー活性層の上にCNT電極を配置することにより、製造を容易にし、 図1に示すように、その後、2つの別々のデバイスを積層する。この方法は、空気を含む、デバイスとして注目に値する-stable CNTカソードを、唯一の乾燥および溶液処理を用いた周囲条件下で完全に作製することができる。 これらは光活性領域からの電子を収集するために、仕事関数を減少させるためにn型ドーピングを必要とするCNTシートは、本質的に良好なカソードはない太陽電池10の。 14 -などのイオン性液体として電解液中に充電電気二重層は、CNT電極の仕事関数11をシフトするために使用することができる。 先行する用紙15に記載され、 図2に示すように、ゲート電圧（V ゲート ） が増加するとき、CNT共通電極の仕事関数は、電極の非対称性を生成する、減少する。これは、OPVのアクセプターから電子を集めるの賛成でOPVのドナーからの正孔のコレクションを防ぎ、およびデバイスは、フォトダイオード15の行動に非効率的なフォトレジスタから変える、ONにしてください。また、エネルギーは、太陽電池15の発電電力に自明と比較されているデバイスと、ゲートリーク電流に起因して失われた電力を充電するために使用されることに留意すべきである。 CNT電極のイオンゲーティング状態の低密度および高による仕事関数に大きな影響を与えるCNT電極における体積に対する表面積の比。類似の方法は、n-Siを16とCNTの界面でショットキー障壁を強化するために使用されている。

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			<td height="21" style="height:21px;width:312px;">Name of Material/ Equipment</td>
			<td style="width:191px;">Company</td>
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			<td style="width:167px;">Comments/Description</td>
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			<td height="21" style="height:21px;">Poly(3,4-ethylenedioxythiophene):poly-(styrenesulfonate)</td>
			<td style="width:191px;">Heraeus</td>
			<td colspan="2">Clevios PVP AI 4083</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:312px;">poly(3- hexylthiophene-2,5-diyl)&#160;</td>
			<td style="width:191px;">Rieke Metals&#160; Inc.</td>
			<td style="width:119px;">P3HT:&#160; P200</td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;">phenyl-C61 -butyric&#160; acid methyl&#160; ester</td>
			<td style="width:191px;">1- Material</td>
			<td style="width:119px;">PC61BM</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;">Poly({4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b&#8242;]dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl})&#160;</td>
			<td style="width:191px;">1- Material</td>
			<td style="width:119px;">PTB7</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;">phenyl-C61 -butyric acid methyl&#160; ester</td>
			<td style="width:191px;">Solenne</td>
			<td style="width:119px;">PC71BM</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">1,8-Diiodooctane</td>
			<td style="width:191px;">Sigma Aldrich</td>
			<td align="right" style="width:119px;">250295</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:312px;">Chlorobenzene</td>
			<td style="width:191px;">Sigma Aldrich</td>
			<td align="right" style="width:119px;">284513</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:312px;">Indium Tin Oxide Coated Glass 15 Ohm/SQ</td>
			<td style="width:191px;">Lumtec</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">S1813</td>
			<td style="width:191px;">UTD Cleanroom</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">MF311</td>
			<td style="width:191px;">UTD Cleanroom</td>
			<td style="width:119px;"></td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;">HCl</td>
			<td style="width:191px;">UTD Cleanroom</td>
			<td style="width:119px;"></td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;width:312px;">Acetone</td>
			<td style="width:191px;">Fisher Scientific</td>
			<td style="width:119px;">A18-20</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:312px;">Toluene</td>
			<td style="width:191px;">Fisher Scientific</td>
			<td style="width:119px;">T323-20</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;width:312px;">Methanol</td>
			<td style="width:191px;">BDH</td>
			<td style="width:119px;">BDH1135-19L</td>
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		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:312px;">Isopropanol</td>
			<td style="width:191px;">Fisher Scientific</td>
			<td style="width:119px;">A416-20</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:312px;">CEE Spincoater</td>
			<td style="width:191px;">Brewer Scientific</td>
			<td style="width:119px;"></td>
			<td>http://www.utdallas.edu/research/cleanroom/tools/CEESpinCoater.htm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:312px;">Contact Printer</td>
			<td style="width:191px;">Quintel</td>
			<td style="width:119px;">Q4000-6</td>
			<td>http://www.utdallas.edu/research/cleanroom/QuintelPrinter.htm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:312px;">CPK Spin Processor</td>
			<td style="width:191px;"></td>
			<td style="width:119px;"></td>
			<td>http://www.utdallas.edu/research/cleanroom/tools/CPKsolvent.htm</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:312px;">Spin Coater</td>
			<td style="width:191px;">Laurell</td>
			<td style="width:119px;">WS-400-6NPP/LITE</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:312px;">Glove Box</td>
			<td style="width:191px;">M-Braun</td>
			<td style="width:119px;">Lab Master 130</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:312px;">Solar Simulator</td>
			<td style="width:191px;">Thermo Oriel/Newport</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:312px;">Keithley 2400 SMU</td>
			<td style="width:191px;">Keithley/Techtronix</td>
			<td align="right" style="width:119px;">2400</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:312px;">Keithley 7002 Multiplexer</td>
			<td style="width:191px;">Keithley/Techtronix</td>
			<td align="right" style="width:119px;">7002</td>
			<td></td>
		</tr>
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			<td height="21" style="height:21px;width:312px;">Ultrasonic Cleaner</td>
			<td style="width:191px;">Kendal</td>
			<td style="width:119px;">HB-S-49HDT</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:312px;">Micropipette</td>
			<td style="width:191px;">Eppendorf</td>
			<td style="width:119px;">200uL</td>
			<td></td>
		</tr>
	</tbody>
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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.

これらのデバイスは、光の最大のスペクトル範囲を吸収することができるように、異なるポリマーから形成されたタンデム型デバイス、著しくバンドギャップの異なるポリマーは、特に、実用的に重要である。このデバイス構造では、PTB7サブセルがバック細胞であり、P3HTは、フロントサブセルである。これは、P3HTサブセルがPTB7サブセルによって吸収されるより長い波長の光に対して主に透...

Watch this Scientific Journal Video about Ambient Method for the Production of an Ionically Gated Carbon Nanotube Common Cathode in Tandem Organic Solar Cells at JoVE.com

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

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.

タンデム有機太陽電池におけるイオン的ゲーテッドカーボンナノチューブ共通カソードの生産のための周囲の方法

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

ambient-method-for-production-an-ionically-gated-carbon-nanotube

Research

JoVE Journal

Engineering

9.3K ビュー.  The University of Texas at Dallas. 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.

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

Controlling the Size, Shape and Stability of Supramolecular Polymers in Water

For aqueous based supramolecular polymers, the simultaneous control over shape, size and stability is very difficult1. At the same time, the ability to do so is highly important in view of a number of applications in functional soft matter including electronics, biomedical engineering, and sensors. In the past, successful strategies to control the size and shape of supramolecular polymers typically focused on the use of templates2,3, end cappers4 or selective solvent techniques5. 
Here we disclose a strategy based on self-assembling discotic amphiphiles that leads to the control over stack length and shape of ordered, chiral columnar aggregates. By balancing electrostatic repulsive interactions on the hydrophilic rim and attractive non-covalent forces within the hydrophobic core of the polymerizing building block, we manage to create small and discrete spherical objects6,7. Increasing the salt concentration to screen the charges induces a sphere-to-rod transition. Intriguingly, this transition is expressed in an increase of cooperativity in the temperature-dependent self-assembly mechanism, and more stable aggregates are obtained. 
For our study we select a benzene-1,3,5-tricarboxamide (BTA) core connected to a hydrophilic metal chelate via a hydrophobic, fluorinated L-phenylalanine based spacer (Scheme 1). The metal chelate selected is a Gd(III)-DTPA complex that contains two overall remaining charges per complex and necessarily two counter ions. The one-dimensional growth of the aggregate is directed by &pi;-&pi; stacking and intermolecular hydrogen bonding. However, the electrostatic, repulsive forces that arise from the charges on the Gd(III)-DTPA complex start limiting the one-dimensional growth of the BTA-based discotic once a certain size is reached. At millimolar concentrations the formed aggregate has a spherical shape and a diameter of around 5 nm as inferred from 1H-NMR spectroscopy, small angle X-ray scattering, and cryogenic transmission electron microscopy (cryo-TEM). The strength of the electrostatic repulsive interactions between molecules can be reduced by increasing the salt concentration of the buffered solutions. This screening of the charges induces a transition from spherical aggregates into elongated rods with a length &gt; 25 nm. Cryo-TEM allows to visualise the changes in shape and size. In addition, CD spectroscopy permits to derive the mechanistic details of the self-assembly processes before and after the addition of salt. Importantly, the cooperativity -a key feature that dictates the physical properties of the produced supramolecular polymers- increases dramatically upon screening the electrostatic interactions. This increase in cooperativity results in a significant increase in the molecular weight of the formed supramolecular polymers in water.

The goal of this experiment is to determine and control the size, shape and stability of self-assembled discotic amphiphiles in water. For aqueous based supramolecular polymers such level of control is very difficult. We apply a strategy using both repulsive and attractive interactions. The experimental techniques applied to characterize this system are broadly applicable.

水中での超分子ポリマーのサイズ、形状と安定性を制御する

For aqueous based supramolecular polymers, the simultaneous control over shape, size and stability is very difficult1. At the same time, the ability to do ...

工学

Fabrication, Densification, and Replica Molding of 3D Carbon Nanotube Microstructures

The introduction of new materials and processes to microfabrication has, in large part, enabled many important advances in microsystems, lab-on-a-chip devices, and their applications. In particular, capabilities for cost-effective fabrication of polymer microstructures were transformed by the advent of soft lithography and other micromolding techniques 1, 2, and this led a revolution in applications of microfabrication to biomedical engineering and biology. Nevertheless, it remains challenging to fabricate microstructures with well-defined nanoscale surface textures, and to fabricate arbitrary 3D shapes at the micro-scale. Robustness of master molds and maintenance of shape integrity is especially important to achieve high fidelity replication of complex structures and preserving their nanoscale surface texture. The combination of hierarchical textures, and heterogeneous shapes, is a profound challenge to existing microfabrication methods that largely rely upon top-down etching using fixed mask templates. On the other hand, the bottom-up synthesis of nanostructures such as nanotubes and nanowires can offer new capabilities to microfabrication, in particular by taking advantage of the collective self-organization of nanostructures, and local control of their growth behavior with respect to microfabricated patterns. 
Our goal is to introduce vertically aligned carbon nanotubes (CNTs), which we refer to as CNT "forests", as a new microfabrication material. We present details of a suite of related methods recently developed by our group: fabrication of CNT forest microstructures by thermal CVD from lithographically patterned catalyst thin films; self-directed elastocapillary densification of CNT microstructures; and replica molding of polymer microstructures using CNT composite master molds. In particular, our work shows that self-directed capillary densification ("capillary forming"), which is performed by condensation of a solvent onto the substrate with CNT microstructures, significantly increases the packing density of CNTs. This process enables directed transformation of vertical CNT microstructures into straight, inclined, and twisted shapes, which have robust mechanical properties exceeding those of typical microfabrication polymers. This in turn enables formation of nanocomposite CNT master molds by capillary-driven infiltration of polymers. The replica structures exhibit the anisotropic nanoscale texture of the aligned CNTs, and can have walls with sub-micron thickness and aspect ratios exceeding 50:1. Integration of CNT microstructures in fabrication offers further opportunity to exploit the electrical and thermal properties of CNTs, and diverse capabilities for chemical and biochemical functionalization 3.

We present methods for fabrication of patterned microstructures of vertically aligned carbon nanotubes (CNTs), and their use as master molds for production of polymer microstructures with organized nanoscale surface texture. The CNT forests are densified by condensation of solvent onto the substrate, which significantly increases their packing density and enables self-directed formation of 3D shapes.

製造、ち密化、および3Dカーボンナノチューブの微細構造のレプリカ成形

The introduction of new materials and processes to microfabrication has, in large part, enabled many important advances in microsystems, lab-on-a-chip ...

Dry Oxidation and Vacuum Annealing Treatments for Tuning the Wetting Properties of Carbon Nanotube Arrays

In this article, we describe a simple method to reversibly tune the wetting properties of vertically aligned carbon nanotube (CNT) arrays. Here, CNT arrays are defined as densely packed multi-walled carbon nanotubes oriented perpendicular to the growth substrate as a result of a growth process by the standard thermal chemical vapor deposition (CVD) technique.1,2 These CNT arrays are then exposed to vacuum annealing treatment to make them more hydrophobic or to dry oxidation treatment to render them more hydrophilic. The hydrophobic CNT arrays can be turned hydrophilic by exposing them to dry oxidation treatment, while the hydrophilic CNT arrays can be turned hydrophobic by exposing them to vacuum annealing treatment. Using a combination of both treatments, CNT arrays can be repeatedly switched between hydrophilic and hydrophobic.2 Therefore, such combination show a very high potential in many industrial and consumer applications, including drug delivery system and high power density supercapacitors.3-5
The key to vary the wettability of CNT arrays is to control the surface concentration of oxygen adsorbates. Basically oxygen adsorbates can be introduced by exposing the CNT arrays to any oxidation treatment. Here we use dry oxidation treatments, such as oxygen plasma and UV/ozone, to functionalize the surface of CNT with oxygenated functional groups. These oxygenated functional groups allow hydrogen bond between the surface of CNT and water molecules to form, rendering the CNT hydrophilic. To turn them hydrophobic, adsorbed oxygen must be removed from the surface of CNT. Here we employ vacuum annealing treatment to induce oxygen desorption process. CNT arrays with extremely low surface concentration of oxygen adsorbates exhibit a superhydrophobic behavior.

This article describes a simple method to fabricate vertically aligned carbon nanotube arrays by CVD and to subsequently tune their wetting properties by exposing them to vacuum annealing or dry oxidation treatment.

カーボンナノチューブアレイの濡れ特性をチューニングするための処置をアニーリングドライ酸化と真空

In this article, we describe a simple method to reversibly  tune the wetting properties of vertically aligned carbon nanotube (CNT) arrays.  Here, CNT ...

Synthesis and Functionalization of Nitrogen-doped Carbon Nanotube Cups with Gold Nanoparticles as Cork Stoppers

Nitrogen-doped carbon nanotubes consist of many cup-shaped graphitic compartments termed as nitrogen-doped carbon nanotube cups (NCNCs). These as-synthesized graphitic nanocups from chemical vapor deposition (CVD) method were stacked in a head-to-tail fashion held only through noncovalent interactions. Individual NCNCs can be isolated out of their stacking structure through a series of chemical and physical separation processes. First, as-synthesized NCNCs were oxidized in a mixture of strong acids to introduce oxygen-containing defects on the graphitic walls. The oxidized NCNCs were then processed using high-intensity probe-tip sonication which effectively separated the stacked NCNCs into individual graphitic nanocups. Owing to their abundant oxygen and nitrogen surface functionalities, the resulted individual NCNCs are highly hydrophilic and can be effectively functionalized with gold nanoparticles (GNPs), which preferentially fit in the opening of the cups as cork stoppers. These graphitic nanocups corked with GNPs may find promising applications as nanoscale containers and drug carriers.

We discussed the synthesis of individual graphitic nanocups using a series of techniques including chemical vapor deposition, acid oxidation and probe-tip sonication. By citrate reduction of HAuCl4, the graphitic nanocups were effectively corked with gold nanoparticles due to the chemically reactive edges of the cups.

コルク栓のように金ナノ粒子と窒素ドープカーボンナノチューブカップの合成と機能化

Nitrogen-doped carbon  nanotubes consist of many cup-shaped graphitic compartments termed as  nitrogen-doped carbon nanotube cups (NCNCs).  These ...

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

The spin echo resolved grazing incidence scattering (SERGIS) technique has been used to probe the length-scales associated with irregularly shaped crystallites. Neutrons are passed through two well defined regions of magnetic field; one before and one after the sample. The two magnetic field regions have opposite polarity and are tuned such that neutrons travelling through both regions, without being perturbed, will undergo the same number of precessions in opposing directions. In this case the neutron precession in the second arm is said to &#34;echo&#34; the first, and the original polarization of the beam is preserved. If the neutron interacts with a sample and scatters elastically the path through the second arm is not the same as the first and the original polarization is not recovered. Depolarization of the neutron beam is a highly sensitive probe at very small angles (&#60;50&#160;&#956;rad) but still allows a high intensity, divergent beam to be used. The decrease in polarization of the beam reflected from the sample as compared to that from the reference sample can be directly related to structure within the sample.
In comparison to scattering observed in neutron reflection measurements the SERGIS signals are often weak and are unlikely to be observed if the in-plane structures within the sample under investigation are dilute, disordered, small in size and polydisperse or the neutron scattering contrast is low. Therefore, good results will most likely be obtained using the SERGIS technique if the sample being measured consist of thin films on a flat substrate and contain scattering features that contains a high density of moderately sized features (30 nm to 5 &#181;m) which scatter neutrons strongly or the features are arranged on a lattice. An advantage of the SERGIS technique is that it can probe structures in the plane of the sample.

Progress has been made in utilizing spin echo resolved grazing incidence scattering (SERGIS) as a neutron scattering technique to probe the length-scales in irregular samples. Crystallites of [6,6]-phenyl-C61-butyric acid methyl ester have been probed using the SERGIS technique and the results confirmed by optical and atomic force microscopy.

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 ...

Fabrication of Low Temperature Carbon Nanotube Vertical Interconnects Compatible with Semiconductor Technology

We demonstrate a method for the low temperature growth (350 &#176;C) of vertically-aligned carbon nanotubes (CNT) bundles on electrically conductive thin-films. Due to the low growth temperature, the process allows integration with modern low-&#954; dielectrics and some flexible substrates. The process is compatible with standard semiconductor fabrication, and a method for the fabrication of electrical 4-point probe test structures for vertical interconnect test structures is presented. Using scanning electron microscopy the morphology of the CNT bundles is investigated, which demonstrates vertical alignment of the CNT and can be used to tune the CNT growth time. With Raman spectroscopy the crystallinity of the CNT is investigated. It was found that the CNT have many defects, due to the low growth temperature. The electrical current-voltage measurements of the test vertical interconnects displays a linear response, indicating good ohmic contact was achieved between the CNT bundle and the top and bottom metal electrodes. The obtained resistivities of the CNT bundle are among the average values in the literature, while a record-low CNT growth temperature was used.

A method for the growth of low temperature vertically-aligned carbon nanotubes, and the subsequent fabrication of vertical interconnect electrical test structures using semiconductor fabrication is presented.

半導体技術との互換性低温カーボンナノチューブ垂直相互接続の作製

We demonstrate a method for the low temperature growth (350 &#176;C) of vertically-aligned carbon nanotubes (CNT) bundles on electrically conductive ...

Quantification of Hydrogen Concentrations in Surface and Interface Layers and Bulk Materials through Depth Profiling with Nuclear Reaction Analysis

Nuclear reaction analysis (NRA) via the resonant 1H(15N,&#945;&#947;)12C reaction is a highly effective method of depth profiling that quantitatively and non-destructively reveals the hydrogen density distribution at surfaces, at interfaces, and in the volume of solid materials with high depth resolution. The technique applies a 15N ion beam of 6.385 MeV provided by an electrostatic accelerator and specifically detects the 1H isotope in depths up to about 2 &#956;m from the target surface. Surface H coverages are measured with a sensitivity in the order of ~1013 cm-2 (~1% of a typical atomic monolayer density) and H volume concentrations with a detection limit of ~1018 cm-3 (~100 at. ppm). The near-surface depth resolution is 2-5 nm for surface-normal 15N ion incidence onto the target and can be enhanced to values below 1 nm for very flat targets by adopting a surface-grazing incidence geometry. The method is versatile and readily applied to any high vacuum compatible homogeneous material with a smooth surface (no pores). Electrically conductive targets usually tolerate the ion beam irradiation with negligible degradation. Hydrogen quantitation and correct depth analysis require knowledge of the elementary composition (besides hydrogen) and mass density of the target material. Especially in combination with ultra-high vacuum methods for in-situ target preparation and characterization, 1H(15N,&#945;&#947;)12C NRA is ideally suited for hydrogen analysis at atomically controlled surfaces and nanostructured interfaces. We exemplarily demonstrate here the application of 15N NRA at the MALT Tandem accelerator facility of the University of Tokyo to (1) quantitatively measure the surface coverage and the bulk concentration of hydrogen in the near-surface region of a H2 exposed Pd(110) single crystal, and (2) to determine the depth location and layer density of hydrogen near the interfaces of thin SiO2 films on Si(100).

We illustrate the application of 1H(15N,&#945;&#947;)12C resonant nuclear reaction analysis (NRA) to quantitatively evaluate the density of hydrogen atoms on the surface, in the volume, and at an interfacial layer of solid materials. The near-surface hydrogen depth profiling of a Pd(110) single crystal and of SiO2/Si(100) stacks is described.

核反応分析と深さ方向分析を通じて表面・界面層とバルク材料中の水素濃度の定量

Nuclear reaction analysis (NRA) via the resonant 1H(15N,&#945;&#947;)12C reaction is a highly effective method of depth profiling that quantitatively and ...

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%.

色素増感太陽電池用二酸化チタンのデジタル印刷

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

Morphology Control for Fully Printable Organic&#8211;Inorganic Bulk-heterojunction Solar Cells Based on a Ti-alkoxide and Semiconducting Polymer

The photoactive layer of a typical organic thin-film bulk-heterojunction (BHJ) solar cell commonly uses fullerene derivatives as the electron-accepting material. However, fullerene derivatives are air-sensitive; therefore, air-stable material is needed as an alternative. In the present study, we propose and describe the properties of Ti-alkoxide as an alternative electron-accepting material to fullerene derivatives to create highly air-stable BHJ solar cells. It is well-known that controlling the morphology in the photoactive layer, which is constructed with fullerene derivatives as the electron acceptor, is important for obtaining a high overall efficiency through the solvent method. The conventional solvent method is useful for high-solubility materials, such as fullerene derivatives. However, for Ti-alkoxides, the conventional solvent method is insufficient, because they only dissolve in specific solvents. Here, we demonstrate a new approach to morphology control that uses the molecular bulkiness of Ti-alkoxides without the conventional solvent method. That is, this method is one approach to obtain highly efficient, air-stable, organic-inorganic bulk-heterojunction solar cells.

Morphology Control for Fully Printable Organic&amp;#8211;Inorganic Bulk-heterojunction Solar Cells Based on a Ti-alkoxide and Semiconducting Polymer

A method for fully printable, fullerene-free, highly air-stable, bulk-heterojunction solar cells based on Ti alkoxides as the electron acceptor and the electron-donating polymer fabrication is described here. Moreover, a method for controlling the morphology of the photoactive layer through the molecular bulkiness of the Ti-alkoxide units is reported.

チタンアルコキシドおよび半導体ポリマーに基づいて、完全に印刷可能な有機 - 無機バルクヘテロ接合太陽電池用形態制御

The photoactive layer of a typical organic thin-film bulk-heterojunction (BHJ) solar cell commonly uses fullerene derivatives as the electron-accepting ...

Precision Milling of Carbon Nanotube Forests Using Low Pressure Scanning Electron Microscopy

A nanoscale fabrication technique appropriate for milling carbon nanotube (CNT) forests is described. The technique utilizes an environmental scanning electron microscope (ESEM) operating with a low pressure water vapor ambient. In this technique, a portion of the electron beam interacts with the water vapor in the vicinity of the CNT sample, dissociating the water molecules into hydroxyl radicals and other species by radiolysis. The remainder of the electron beam interacts with the CNT forest sample, making it susceptible to oxidation from the chemical products of radiolysis. This technique may be used to trim a selected region of an individual CNT, or it may be used to remove hundreds of cubic microns of material by adjusting ESEM parameters. The machining resolution is similar to the imaging resolution of the ESEM itself. The technique produces only small quantities of carbon residue along the boundaries of the cutting zone, with minimal effect on the native structural morphology of the CNT forest.

Low pressure scanning electron microscopy in a water vapor ambient is used to machine nanoscale to microscale features in carbon nanotube forests.

低圧走査型電子顕微鏡を用いたカーボンナノチューブの森の精密フライス

A nanoscale fabrication technique appropriate for milling carbon nanotube (CNT) forests is described. The technique utilizes an environmental scanning ...