通过氨基醇催化合复合物的醇的电氧化
Kristen R Brownell1, Charles C L McCrory, Christopher E D Chidsey
1Department of Chemistry, Stanford University , Stanford, California 94305-5080, United States.
Journal of the American Chemical Society
|September 19, 2013
概括
在石墨电极上的催化剂有效氧化甲醇. 表面结合的氧复合物调解了这种电氧化过程,产生了酸盐.
科学领域:
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- 复合物是有效的转移化催化剂.
- 电催化为化学转化提供了一个可持续的途径.
研究的目的:
- 为了研究复合物的电催化活性,以氧化酒精.
- 为了阐明甲醇电氧化介于表面支持的物种的机制.
主要方法:
- 催化剂的物理吸收到边缘平面石墨电极上.
- 电化学测量包括循环电压测量和Koutecky-Levich分析.
- 机械学研究的光谱和质谱技术 (1H NMR,DESI-MS).
主要成果:
- 石墨电极上的催化剂对甲醇氧化表现出电催化活性.
- 在缓冲溶液 (pH 11.5) 中的甲醇 (1.23 M) 的电氧化显示了560mV与NHE的初始电流.
- 库特基-莱维奇分析表明,一个四电子氧化过程的速度为1.35M-1s-1在750mV.
结论:
- 在石墨电极上固定的转移化催化剂是氧化酒精的活性电催化剂.
- 甲醇的电氧化形成是由表面支的氧复合体介导的.
- 这项研究强调了以为基础的电催化剂在高效的甲醇氧化中的潜力.
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