酸性電解質における水素進化の抑制 電気化学的CO2減少
Christoph J Bondue1, Matthias Graf1,2, Akansha Goyal1
1Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
Journal of the American Chemical Society
|December 28, 2020
まとめ
金電極での二酸化炭素 (CO2) の電気化学的減少を最適化するには,CO2の偏圧と陽子の濃度を注意深く制御する必要があります. 高圧のCO2はCOの形成を促進し,水素の進化を抑制し,ほぼ100%のファラダイの効率を達成します.
科学分野:
- 電気化学
- カタリシス
- 表面科学
背景:
- 二酸化炭素 (CO2) の電気化学的減少は,持続可能な燃料と化学製品の有望な経路です.
- 軽度の酸性条件は,競合する陽子の減少により,CO2削減の選択性に対してユニークな課題を提示します.
研究 の 目的:
- 軽度の酸性条件下での金電極でのCO2の電気化学的還元を調査する.
- 炭素一酸化物 (CO) の形成を最大化し,水素の進化を抑制するための最適な条件を決定する.
主な方法:
- 微分電気化学質量スペクトル検査 (DEMS) を用いて,ガス産物 (H2,CO) と消費されたCO2を定量化した.
- CO2の偏圧 (0. 1−0. 5バー) と陽子濃度 (1−0. 25mM) を体系的に変化させました.
主要な成果:
- CO2の偏圧を増加させると,COの形成率とファラダイク効率が100%に近づく.
- 二酸化炭素の減少率は,電極表面にある陽子を消費することによって,水素の進化を効果的に抑制する.
- 酸性CO2電解剤の設計原理が提案されている.CO/OH-形成率は,電極への陽子の質量輸送に一致しなければならない.
結論:
- 金の電極で軽く酸性CO2の電気還元は,COに対する高い選択性を達成することができます.
- 二酸化炭素の部分圧力を最適化し,陽子の質量輸送を管理することによって,水素の進化を抑制することが可能である.
- この研究は,効率的で選択的な酸性CO2電解剤の設計に重要な洞察を提供します.
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