区分同质和异质的水氧化催化剂:确认[Co4 ((H2O) 2 ((α-PW9O34) 2)) 10-是一种分子水氧化催化剂
James W Vickers1, Hongjin Lv, Jordan M Sumliner
1Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University , Atlanta, Georgia 30322, United States.
Journal of the American Chemical Society
|August 28, 2013
概括
聚氧甲离子Co4POM作为分子水氧化催化剂,而不是氧化物. 实验证实了 Co4POM 的存在.
科学领域:
- 催化剂是一种催化剂.
- 无机化学 无机化学 有机化学
- 电化学 电化学 电化学
背景情况:
- 区分同质和异质催化是很有挑战性的.
- 水氧化催化剂[Co4 ((H2O) 2 ((PW9O34) 2)) ((10-) (Co4POM) 最初被报道为一种高效的分子催化剂.
- 随后的研究质疑氧化物 (CoOx) 副产品是否对Co4POM的活性负责.
研究的目的:
- 详细研究由Co4POM负责水氧化催化作用的活性物种.
- 确定Co4POM是否作为分子催化剂或异质CoOx的前体.
主要方法:
- 使用阴极吸附剥离电压测量和感应合等离子体质谱测量量释放的Co2+ (aq) 的量化.
- 对Co4POM,Co2+) 和CoOx的催化O2进化依赖缓冲器,pH和催化剂度的分析.
- 溶剂提取实验以区分Co4POM与Co2+ (aq) 和CoOx.
主要成果:
- 释放的的数量无法解释观察到的水氧化活性.
- Co4POM,Co2+) 和CoOx对反应条件有明显的依赖.
- 与Co2+) 和CoOx.不同的是,Co4POM被选择性地提取到烯中.
结论:
- 在报告的条件下,Co4POM作为分子水氧化催化剂起作用.
- 催化活性归因于完整的Co4POM物种,而不是CoOx副产品.
- 以前的研究表明CoOx作为活性物种与Co4POM在不同的条件下已知的分解途径相协调.
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