用催化剂设计的质子转移途径用于固态电解质中的选择性过氧化电合成
Jun Wang1,2, Junheng Huang1,2, Chunguang Jia3
1State Key Laboratory of Structural Chemistry, and Fujian Provincial Key Laboratory of Materials and Techniques toward Hydrogen Energy, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian, 350002, P.R. China.
Angewandte Chemie (International ed. in English)
|June 26, 2025
概括
研究人员开发了一种新的催化剂,用于使用纯水进行高效的过氧化 (H2O2) 电合成. 这一突破澄清了固体电解质细胞中的质子化机制,为改进的H2O2生产铺平了道路.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
背景情况:
- 基于聚合物的固体电解质 (SE) 细胞为电化学过氧化 (H2O2) 合成提供了一个有前途的途径.
- 在SE细胞中使用纯水的双电子氧降解反应 (2e−-ORR) 的精确质子化机制仍然不太清楚.
- 兰木尔-欣舍尔伍德 (LH) 和伊利-里达尔 (ER) 路径在理论上都是可能的,但在SE条件下缺乏实验验证.
研究的目的:
- 用纯水阐明控制SE细胞中H2O2电合成的质子化机制.
- 设计和评估一种控制质子转移通路的新型催化剂.
- 建立用于高效固态H2O2生产的催化剂设计原则.
主要方法:
- 设计和合成一个分层的Ni─N2─C─O单原子/NiO纳米集团联合装饰的多孔碳纳米板催化剂 (NiSA-NiO/pCNs).
- 在一个多孔的SE细胞中进行电化学表征,以评估H2O2生产效率和法拉第效率.
- 在现场拉曼光谱,动态同位素效应研究,密度函数理论 (DFT) 模拟来分析反应中间体和pH.
主要成果:
- NiSA-NiO/pCNs催化剂实现了高法拉代效率97%,H2O2部分电流密度为356mA cm−2.2.
- 实验和理论分析表明,NiO纳米集群通过快速水解离和质子转移促进了Eley-Rideal (ER) 机制.
- 没有NiO的催化剂优先采用Langmuir-Hinshelwood (LH) 机制,涉及表面吸附的中间体.
结论:
- 纳米集群在激活SE细胞中H2O2电合成的ER通路方面发挥着至关重要的作用.
- 催化剂设计有效控制质子转移机制,区分ER和LH通路.
- 这项研究为优化固态H2O2电合成提供了基本的理解和设计策略.
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