COPフィルムの光譜分析により,水素進化反応を電触媒化する
Fadl H Saadi, Azhar I Carim, Walter S Drisdell1
1Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|August 29, 2017
まとめ
コバルト・フォスフィード (CoP) のような移行金属フォスフィードは,酸性溶液における水素進化反応 (HER) の効果的な触媒である. オペラントスペクトロスコーピーは,活性HER触媒が無形であり,ほぼゼロバルントのコバルトと減少したリンを特徴としています.
科学分野:
- 材料科学
- 電気化学
- カタリシス
背景:
- 移行金属フォスフィードは,電気化学的水素進化反応 (HER) のための高い触媒活性を示しています.
- これらの材料は,酸性環境での化学的腐食にも耐性があり,電気化学的用途に適しています.
研究 の 目的:
- コバルト・フォスフィード (CoP) 触媒の化学的特徴を特定する.
- 酸性環境でのHER中の触媒の振る舞いを理解するためです.
- 操作条件下で触媒作用を起こす活性種を明らかにする.
主な方法:
- 電気化学的水素進化反応 (HER) 0.500 M H2SO4 ((aq) で測定した.
- エックス・シットーとイン・シットー/オペラント・ラーマン光学
- エックス・シットーとイン・シットー/オペラントのX線吸収光譜 (XAS)
主要な成果:
- Ex situ 分析により,Co 種とP 種の混合酸化状態を持つ複数の秩序と無秩序の相が明らかになった.
- オペラントスペクトロスコピーは,活性触媒が主に無形であることを示した.
- 活性電気触媒は主にゼロバルトに近いコバルト (Co) と還元されたリン (P) 種で構成されています.
結論:
- コバルト・フォスフィード (CoP) は,酸性環境でHERに対する優れた触媒性能を示す.
- オペラント条件下での活性な触媒種は,無形であり,減少したCoとPに富んでいるので,準備された材料と異なる.
- 電気化学反応中の触媒の化学状態に関する重要な洞察を,スペクトロスコーピテクニックが提供します.
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