分子触媒でCO2をメタノールにドミノ電還元
Yueshen Wu1,2, Zhan Jiang3, Xu Lu1,2
1Department of Chemistry, Yale University, New Haven, CT, USA.
Nature
|November 29, 2019
まとめ
研究者らは,効率的な二酸化炭素 (CO2) をメタノールに還元するための新しい分子電気触媒を開発しました. この突破は炭素排出から再生可能燃料の生産を促進します
科学分野:
- 電気化学
- カタリシス
- 材料科学
背景:
- 電気化学による二酸化炭素 (CO2) 削減は,再生可能エネルギーを利用して排出物を有価な化学物質に変換する道を示しています.
- 現在の分子触媒はしばしば緩やかな運動性を示し,2電子の還元プロセスに限定されます.
- 移行金属複合体は広く研究されていますが,より高い価値の製品を得るために苦労しています.
研究 の 目的:
- CO2を多電子分解して有価な製品に変換する分子触媒を開発する.
- CO2の電還元のための固定コバルトフタロシアニンの性能と安定性を調査する.
- 反応メカニズムを理解し,触媒の長寿を改善するための戦略を特定する.
主な方法:
- 炭素ナノチューブでコバルトフタロシアニンを固定する
- ほぼ中性電解質のCO2の電気化学的還元
- 触媒活性,選択性,ファラダイの効率を特徴づけている.
- 触媒の安定性と分解経路を調査する
主要な成果:
- 炭素ナノチューブに固定されたコバルト・フタロシアニンは 高選択性でCO2をメタノールに 6電子減量する触媒となった.
- -0.94V対RHEで40%以上のファラダイク効率と10mA/cm2以上の部分電流密度を達成した.
- アミノ置換剤によって緩和された,フタロシアニンリガンド減少による触媒分解を特定した.
- 12時間以上 安定したメタノール生産が証明された
結論:
- コバルトフタロシアニンは CO2 をメタノールに効率的に変換するための有望な分子電気触媒です.
- 触媒は,CO中介物質を含むドミノプロセスを経て動作し,重要な活動と選択性を達成します.
- リガンド改変など,触媒の安定性を高める戦略は,実用的な応用において極めて重要です.
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