成果報告書詳細
管理番号20120000000524
タイトル*平成23年度中間年報 最先端研究開発支援プログラム 低炭素社会に資する有機系太陽電池の開発 電荷分離・輸送・貯蔵ポリマーの複合機能制御と新型湿式太陽電池の創出(サブテーマ4)
公開日2013/6/25
報告書年度2011 - 2011
委託先名学校法人早稲田大学
プロジェクト番号P09026
部署名新エネルギー部
和文要約和文要約等以下本編抜粋:1. 研究開発の内容及び成果等
レドックスポリマーに増感色素分子を組み込んだ複合系を対象として、光誘起電子移動とそれにともなう輸送現象の全容解明により、色素増感太陽電池の多様化に将来必須となる革新的な電荷分離・輸送・貯蔵ポリマーを創出することを目的としている。電気化学的に可逆な酸化還元を示すニトロキシドラジカル誘導体において、色素への電子注入が効率よく生起し、速い自己電子交換反応や物質拡散に基づく効率的な電荷輸送が可能となることを実証するとともに、酸化還元電位の制御により高い光起電力を発生することを示す。本年度は、高反応性ラジカル種であるアダマンタン置換ニトロキシドラジカルを中心とした一連の有機レドックス分子を色素増感太陽電池における有機系メディエータとして適用し、メディエータ濃度、支持塩濃度、添加剤、吸着剤および色素の最適化により、有機レドックスを用いた色素増感太陽電池で変換効率8.6 %を達成した。
英文要約Founding Program for World-Leading Innovative R&D on Science and Technology (FIRST-Program). Development of Organic Photovoltaic toward a Low-Carbon Society: Sub-project No.4 “Charge-Separation, -Propagation, and -Storage Functions of Redox Polymers and their Application to Photovoltaic Cells”
In this project, nitroxide radical derivatives including their polymers, such as 2,2,6,6-tetramethylpiperidine-1-oxy (TEMPO) and TEMPO-substituted polymers, and organic redox molecules were applied to dye-sensitized solar cells (DSSCs) as redox mediator electrolytes .The optimized DSSC utilizing the highly reactive nitroxide radical mediator accomplished 8.6 % of the conversion efficiency. The results were summarized as following.
(1) Co-absorption additives for the DSSC utilizing the TEMPO mediator
Co-absorption additives, chenodeoxycholic acid (CDCA), 1-butylcalbonic acid, and 1-calboxyl-N,N,N-trimethylmethaneammonium, were examined in the DSSC using the TEMPO mediator electrolyte, to suppress undesired back electron-transfer from titania surface to the TEMPO cation. For example, the CDCA addition yielded improvement of the efficiency.
(2) Optimization of the DSSC utilizing the nitroxide radical mediators
Azaadamantane-1-oyl (AZA) exhibited highly efficient diffusion, large electron-transfer rate constant and electron self-exchange reaction rate constant, based on its lower steric hindrance around the nitroxide reaction center than TEMPO. Dye-sensitizer molecules, electrolyte additives, concentration of the supporting electrolyte salt and the mediator, and titania electrode were optimized. The DSSC utilizing AZA displayed very high fill factor (0.75) due to the low cell resistance derived from the effective charge-propagation and the mediator regeneration on counter electrode. IPCE of the cell was beyond 70 % in the visible region. This result strongly supported the improvement of short circuit current density (Jsc = 13.3 mA/cm2). The conversion efficiency of the cell reached to 8.6 %. The DSSC utilizing TEMPO also improved the - up to 7.0 %.
(3) Polymerization of EDOT for a pseudo-solid state DSSC
To achieve a pseudo-solid state DSSC, 3,4-ethylenedioxythiophene (EDOT) was polymerized by using a vapor-phase oxidant such as iodide and nitrosonium hexafluorophosphate, in a titania porous electrode. SEM Image showed the PEDOT polymer filled up the titania pore, and conductivity of the PEDOT electrode increased to 10-1 S/cm2.
(4) Synthesis of dye-redox site coupled molecules
Dye molecules substituted with a redox active moiety was designed and synthesized. A nitronylnitroxide radical was employed as the redox active moiety and a triarylamine derivative-combined oligothiophene was as the dye moiety because of its deeper redox potential than that of the nitroxide mediator. Property of the coupled molecule is now being studied.
ダウンロード成果報告書データベース(ユーザ登録必須)から、ダウンロードしてください。

▲トップに戻る