効率的な過酸化水素の電気化学合成のための炭素材料のボロン窒素群の設計
Shucheng Chen1, Zhihua Chen1, Samira Siahrostami1
1SUNCAT Center for Interface Science and Catalysis, Department of Chemical Engineering , Stanford University , Stanford , California 94305 , United States.
Journal of the American Chemical Society
|June 7, 2018
まとめ
埋め込まれた六角性化物 (h-BN) ドメインを持つボロンと窒素ドーピングされた炭素は,2電子酸素還元反応 (ORR) の触媒活性が強化されています. この研究は,これらのBCN材料を電気化学的過酸化水素生産のための新しい触媒として特定しています.
科学分野:
- 材料科学
- 電気化学
- カタリシス
背景:
- ヘテロアトムドーピングされた炭素は,電気化学反応の有望な触媒である.
- ボロンと窒素 (BCN) との共同ドーピングにより,酸素還元反応 (ORR) の活性が強化されます.
- BCNの重要な活動に寄与する特定の活動地と要因については,さらなる調査が必要である.
研究 の 目的:
- 組み込まれた六角性化物 (h-BN) ドメインを持つBCN材料を合成し,体系的に研究する.
- これらのBCN材料の電気化学性能をORRのために調査する.
- ORR触媒と過酸化水素生成における炭素におけるh-BNドメインの役割を明らかにする.
主な方法:
- BCNの材料の容易で制御された合成
- グラフィティック構造の中に埋め込まれたh-BNドメインを特徴付けるためのX線スペクトロスコーピー.
- 2電子 ORRの電気化学性能試験
- 触媒メカニズムをモデル化するための密度関数理論 (DFT) の計算.
主要な成果:
- 合成されたBCN材料は,グラフィットの炭素構造の中にh-BNドメインが埋め込まれています.
- これらのBCN材料は,2e- ORRからH2O2に対して,単独ドーピングされた材料と比較して優れた活性と選択性を示しています.
- DFT計算は,h-BNドメインとグラフェンの間のインターフェイスでユニークな触媒的振る舞いを明らかにします.
結論:
- 炭素構造に埋め込まれたh-BNドメインは,電気化学的H2O2生産のための新しいシステムとして識別されています.
- h-BNドメインとグラフェンの間のインターフェースは,H2O2の生成を優先させる上で重要な役割を果たします.
- この研究は,選択的ORRのためのBCN材料の触媒メカニズムに関する基本的な洞察を提供します.
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