通过空位缺陷介导的中介吸附配置的改变来提高低协调的Co-N-C催化剂的进化活动
Qianwei Song1, Zhichao Gong1, Jianbin Liu1
1State Key Laboratory for Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education and College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, P. R. China.
一种新的--碳催化剂,具有量身定制的低协调位点和缺陷,可以提高演化反应 (HER) 的活性. 这一突破为贵金属催化剂提供了一个有希望的,具有成本效益的替代品.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
背景情况:
- --碳 (Co─N─C) 单原子催化剂 (SACs) 被探索为替代贵金属的演化反应 (HER).
- 催化剂活动受到金属中心的协调环境的显著影响.
研究的目的:
- 制定创建低协调和不对称的Co─N─C站点的策略,并有相邻的空缺缺陷.
- 调查这些工程站点对 HER 性能的影响,并了解底层结构-活动关系.
主要方法:
- 采用NaHCO3蚀刻策略,将平面孔引入碳基板.
- 制造具有空缺缺陷附近的Co-N3位点的Co-NC催化剂.
- 电化学表征 (超电位,Tafel斜率,周转频率) 和理论计算 (DFT).
主要成果:
- 合成的催化剂显示出高的HER活性:78 mV的超电位为10 mA cm-2 ,Tafel斜率为45.2 mV dec-1 ,周转频率为1.67 s-1.
- 在Co─N3位点附近的空缺缺陷被证明可以调节电子结构并改变从顶部到侧面模式的吸附.
- 由于吸附配置的改变,吸附强度的减弱导致了 HER 活性的改善.
结论:
- NaHCO3蚀刻策略有效地创建了缺陷丰富,低协调的SAC,用于增强HER.
- 空位缺陷在优化Co-N-C催化剂的电子特性和结能方面发挥着至关重要的作用.
- 这项工作为SACs提供了关于原子级结构-活性关系的见解,指导了未来的催化剂设计.
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