使用电子介质解锁光催化生产的关键
Ming Shi1, Xuan Wu1,2, Yue Zhao1
1State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, PR China.
Journal of the American Chemical Society
|January 18, 2025
概括
在催化剂上使用氧化 (CrO2) 修改的新策略增强了光催化水分. 这防止了穿离子吸附,提高了演化反应 (HER) 的活性和Z-方案的效率.
科学领域:
- 材料科学
- 光催化
- 可再生能源
背景情况:
- 与有机牺牲试剂相比,在使用电子介质的Z方案中,粒子光催化水分解面临着减少演化反应 (HER) 活性的挑战.
- 这种性能下降的根本原因,特别是离子在催化剂表面的强吸附,仍未确定.
研究的目的:
- 通过使用电子介质,确定Z模式光催化水分系统中HER活性下降的原因.
- 通过解决穿离子吸附,开发一种增强HER活性和整体Z模式水分性能的策略.
主要方法:
- 作为减少HER活性的原因,研究了离子在催化剂表面的吸附.
- 开发了一种使用氧化物 (CrO2) 种类在金属催化剂 (Pt,Ru) 上的表面修饰策略,用于对可见光敏感的光催化剂 (BaTaO2N,SrTiO3:Rh).
- 评估了CrO2修饰对各种穿离子中的HER活性及其对Z模式水分裂性能的影响.
主要成果:
- 证明在催化剂上强烈吸附的穿离子抑制了质子的减少,并促进了反向反应,导致HER活性下降.
- 展示了使用CrO2选择性表面修饰显著削弱金属催化剂和穿离子之间的相互作用.
- 对BaTaO2N和SrTiO3:Rh的光催化HER活动达到了一到两级的改善,并提高了Z模式的水分性能.
结论:
- 在Z模式光催化水分裂中,离子在催化剂表面的强吸附是减少HER活性的主要原因.
- 用CrO2进行表面修饰是防止穿离子吸附,促进质子吸附和抑制反向反应的有效策略.
- 这种方法为构建高效的Z模式光催化水分系统提供了可行的途径.
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