太陽光光電解における表面再結合のほぼ完全な抑制は",Co-Pi"触媒改変W:BiVO4による
Diane K Zhong1, Sujung Choi, Daniel R Gamelin
1Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States.
Journal of the American Chemical Society
|September 28, 2011
まとめ
コバルト・リン・窒素 (Co-Pi) 電気触媒をトングステン・ドーピングされたビスムート・ヴァナダート (W:BiVO(4)) フォトアノードに添加すると,太陽光水酸化が著しく改善されます. この表面改変により,効率が向上し,光電化学 (PEC) 水分裂におけるエネルギー損失が軽減されます.
科学分野:
- マテリアルサイエンス 材料科学
- 電気化学 電気化学について
- 再生可能エネルギーの再生可能エネルギー
背景:
- 太陽光による水分分離は,再生可能水素生産の鍵となる技術です.
- トングステン添加ビスムートヴァナデート (W:BiVO(4) は,有望なフォトアノード材料である.
- 効率的な水酸化電触媒は,太陽光水分解性能を改善するために不可欠です.
研究 の 目的:
- 地球に豊富に存在するコバルト・リン・窒素 (Co-Pi) 電気触媒が,太陽光水酸化のためのW:BiVO(4) フォトアノードに与える影響を調査する.
- フォト電気化学 (PEC) 技術を用いて,Co-Piで改造されたW:BiVO(4) フォトアノードの性能向上を評価する.
- 低コストの太陽光水分化のアプリケーションのためのこのCo-Pi変更戦略の可能性を評価する.
主な方法:
- W:BiVO(4) フォトアノードの製造.
- Co-Pi電触媒によるW:BiVO(4) の表面改変.
- 代替基質としてH(2) O(2) を使った実験を含む,pH8での光電気化学 (PEC) 測定.
- Co-Pi/α-Fe(2) O(3) のフォトアノードによる結果の比較.
主要な成果:
- Co-Piの改変により,pH8.0で持続的なPEC水酸化の発生ポテンシャルにおいて,重要なカソードシフト (∼440 mV) が誘発された.
- Co-PiをW:BiVO(4) フォトアノードとインターフェイスすることで,表面電子孔再結合損失を効果的に抑制しました.
- Co-Pi/W:BiVO(4) システムで,RHEと比較して≤310mVの低い絶対発生ポテンシャルを達成しました.
結論:
- Co-Pi/W:BiVO(4) フォトアノードは,非常に効率的な太陽光水酸化を証明しています.
- 観測された改善は,全体的な太陽光水分解のための低コストのタンデムPEC電池の開発に有望である.
- この表面改変戦略は,他の候補光電極材料にも適用できます.
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