Amorphous low-coordinated cobalt sulphide nanosheet electrode for electrochemically synthesizing hydrogen peroxide in acid media

作者：Chen, Zhenglin; Liu, Guangzhen; Cao, Wenjing; Yang, Lixia^*; Zhang, Longshuai; Zhang, Shuqu; Zou, Jianping; Song, Renjie; Fan, Wenhong; Luo, Shenglian^*; Dionysiou, Dionysios D.

来源：Applied Catalysis B: Environmental , 2023, 334: 122825.

DOI：10.1016/j.apcatb.2023.122825

• Low-coordination
• H2O2
• 2e(-) oxygen reduction reaction
• CoSx
• Amorphous

This study investigates in-depth the local atomic environment-property relationship of amorphous low-coordination catalysts toward the 2e(-) oxygen reduction reaction (ORR). Here, an ethanol-assisted slow nucleation strategy was adopted to flexibly regulate the intrinsic activity of CoSx nanostructures for efficient 2e(-) ORR by oriented control the coordination number of Co. When Co and S form Co-S-4 coordination structures, the CuNW@CoS4 exhibits an ultra-low overpotential (0.018 V) with 93 % H2O2 selectivity, and 91 % Faraday efficiency in acidic media at 0.1 V-RHE. Furthermore, thus produced H2O2 satisfies in-situ organic pollutants degradation by electro-Fenton. XAS and DFT calculations unveil the S-induced forming of abundant low-coordinated Co atoms as active sites in Co-S4, validating that a favorable D-band energy level of Co center can weaken the OOH* adsorption for accelerating the H2O2 production kinetics. This work is anticipated to enlighten the rational design of high-performance ORR catalysts for practically feasible H2O2 electrosynthesis toward wastewater remediation.

• 单位
  北京航空航天大学; 南昌航空大学