在Co-N-C原子接口上调整质子亲和力,以解活动-选择性权衡在酸性氧降低到H2O2
Shanyong Chen1,2,3, Tao Luo1, Jingyu Wang2
1Hunan Joint International Research Center for Carbon Dioxide Resource Utilization, State Key Laboratory of Powder Metallurgy, School of Physics, Central South University, 410083, Changsha, China.
Angewandte Chemie (International ed. in English)
|November 5, 2024
概括
研究人员开发了一种新的催化剂 (Co1-NBC),它打破了两电子氧降解反应 (2e-ORR) 中的活性-选择性权衡. 这种添加剂的催化剂增强了H2O2的产生,在酸性介质中具有高活性和选择性.
科学领域:
- 电触媒溶解是一种电触媒.
- 材料科学 材料科学 材料科学
- 绿色化学 绿色化学
背景情况:
- 产生过氧化 (H2O2) 的两电子氧降解反应 (2e-ORR) 对各种化学过程至关重要.
- 2e-ORR的一个关键挑战是活动选择性权衡,通常由含氧中间体的吸附强度决定.
- 目前的催化剂难以同时实现高活性和选择性,从而限制了高效的H2O2生产.
研究的目的:
- 开发一种新的战略,以克服2e-ORR中的活动选择性权衡.
- 为了增强催化活性和H2O2形成的选择性.
- 研究2e-ORR机制中质子与中间体相互作用的作用.
主要方法:
- 一个单原子催化剂的设计和合成,其中异原子被添加到CoN4 (Co1-NBC) 的第二个协调球中.
- 在酸性介质中对催化剂性能进行电化学表征,包括开始电位和H2O2选择性测量.
- 在流细胞条件下评估H2O2的生产率和长期稳定性.
主要成果:
- Co1-NBC催化剂表现出显著的2e-ORR活性,其发病潜力为0.724V与RHE,H2O2选择性为94%.
- 兴奋剂增强了质子亲和力,促进质子对*OOH中间体的攻击,并促进H2O2的形成.
- 催化剂实现了202.7毫克cm-2h-1的高H2O2生产率和在200mAcm-2下60小时的优异稳定性.
结论:
- 调节*OOH中间体与质子相互作用是一种有效的策略,可以打破2e-ORR中的活动选择性权衡.
- Co1-NBC催化剂在高度活跃和选择性H2O2生产方面取得了重大进展.
- 这项工作为设计用于高效的H2O2合成的先进电催化剂提供了新的视角.
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