Lin Ze, Lohwacharin Jenyuk, Li Yahui, Wang Ying
State Key Laboratory of Water Pollution Control and Green Resource Recycling, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.
Department of Environmental and Sustainable Engineering, Faculty of Engineering Chulalongkorn University, Bangkok, 10330, Thailand.
J Colloid Interface Sci. 2025 Aug 25;702(Pt 1):138814. doi: 10.1016/j.jcis.2025.138814.
Transition metal single-atom catalysts (TM-SACs) have emerged as promising electrocatalysts for the two-electron oxygen reduction reaction (2eORR) due to their exceptional atomic utilization efficiency and tunable electronic structures. Nevertheless, the practical application of TM-SACs is constrained by their relatively low metal loading, which adversely affects their catalytic performance. Herein, we developed a universal defect-mediated strategy to fabricate TM-SACs with high metal loading. Nitrogen-doped carbon dots (NCDs) derived from ethylene diamine tetraacetic acid (EDTA) serve as an ideal support material, where the confined spatial dimensions and abundant defect sites effectively isolate metal atoms while preventing their aggregation. To validate the versatility of this synthetic strategy, we successfully prepared a series of TM-SACs (denoted as TMSA-NC, where TM = Fe, Ni, Cu) with high metal loading reaching 6.87 wt%. Intriguingly, the ORR selectivity can be precisely modulated toward the 2e pathway for hydrogen peroxide (HO) synthesis by varying the central metal atom. Notably, the NiSA-NC catalyst exhibits outstanding performance in neutral conditions, achieving 81.0 % HO selectivity and a remarkable production rate of 2972.2 mmol L h g, surpassing most previously reported catalysts. This work not only provides a general methodology for constructing high-loading TM-SACs but also offers new insights into the rational design of efficient electrocatalysts for sustainable chemical synthesis.
过渡金属单原子催化剂（TM-SACs）因其卓越的原子利用效率和可调控的电子结构，已成为用于双电子氧还原反应（2eORR）的有前景的电催化剂。然而，TM-SACs的实际应用受到其相对较低的金属负载量的限制，这对其催化性能产生不利影响。在此，我们开发了一种通用的缺陷介导策略来制备高金属负载量的TM-SACs。源自乙二胺四乙酸（EDTA）的氮掺杂碳点（NCDs）用作理想的载体材料，其受限的空间尺寸和丰富的缺陷位点有效地隔离了金属原子，同时防止其聚集。为了验证这种合成策略的通用性，我们成功制备了一系列高金属负载量达到6.87 wt%的TM-SACs（表示为TMSA-NC，其中TM = Fe、Ni、Cu）。有趣的是，通过改变中心金属原子，可以将ORR选择性精确地调节至用于过氧化氢（HO）合成的2e途径。值得注意的是，NiSA-NC催化剂在中性条件下表现出优异的性能，实现了81.0%的HO选择性和2972.2 mmol L h g的显著产率，超过了大多数先前报道的催化剂。这项工作不仅为构建高负载量的TM-SACs提供了一种通用方法，还为可持续化学合成的高效电催化剂的合理设计提供了新的见解。
