使用强大的多功能复合物的光催化CO2减少,以选择性形成酸
Kenji Kamada1, Jieun Jung1, Taku Wakabayashi1
1Department of Chemistry, Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan.
Journal of the American Chemical Society
|May 28, 2020
概括
一种新的光催化剂Mes-IrPCY2有效地将二氧化碳转化为高选择性酸. 这一突破实现了没有额外光敏感剂的二氧化碳减少光催化剂的最高营业额.
科学领域:
- 无机化学
- 光催化
- 绿色化学
背景情况:
- 减少二氧化碳对于缓解气候变化和发展可持续化学过程至关重要.
- 开发高效和选择性的二氧化碳转化光催化剂仍然是一个重大挑战.
- 现有的光催化剂通常需要光敏剂或表现出有限的效率和选择性.
研究的目的:
- 开发一种高效的四牙PNNP类型的光催化剂,用于减少二氧化碳.
- 研究开发的催化剂的光催化活性和选择性.
- 阐明酸选择性形成中的关键中间体.
主要方法:
- 合成和表征四牙PNNP类型的复合物 (Mes-IrPCY2).
- 在可见光照射下,在牺牲电子供体 (BIH) 的存在下使用Mes-IrPCY2进行光催化降低CO2.
- 使用气色谱和光谱分析产品 (甲酸和一氧化碳).
- 使用电子磁共振 (EPR) 和紫外线光谱的反应中间体的研究.
主要成果:
- Mes- IrPCY2 显示出高的光催化活性,减少二氧化碳,产生87%的选择性甲酸 (HCO2H) 和一氧化碳 (CO).
- 催化剂的周转率为2560,是没有额外光敏感剂的二氧化碳减排光催化剂中报告的最高值.
- 在生成HCO2H和CO时,确定了49%的量子产量.
- 谱学研究确定了一电子减少的Mes-IrPCY2物种是选择性酸形成的关键中间体.
结论:
- 开发的Mes-IrPCY2是一种高效和选择性的二氧化碳降解酸的光催化剂.
- 催化剂的性能超过了不使用额外光敏剂的现有系统.
- 了解一个电子减少的中间体为设计未来的先进的二氧化碳转换光催化剂提供了洞察力.
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