Zinc Vaporization Induced Formation of Desired Ni Nanoparticles Coated with Ultrathin Carbon Shells for Efficient Electrocatalytic H2 Production Coupling with Methanol Upgrading

• Published in: ACS applied materials & interfaces 2024-10, Vol.16 (39), p.52326-52338
• Main Authors: Hou, Kexian, Zhang, Shizhen, Yin, Peng, Liu, Tao, Cao, Yanfeng, Wang, Mingxi, Zhan, Weiting, Wu, Ling
• Format: Article
• Language: English
• Subjects: Energy, Environmental, and Catalysis Applications
• ISSN: 1944-8244; 1944-8252; 1944-8252
• DOI: 10.1021/acsami.4c10405

The integration of the hydrogen evolution reaction (HER) with the methanol oxidation reaction (MOR) has been demonstrated to be a viable strategy for the energy-saving generation of H2 and value-added formate, which relies primarily on highly active and cost-effective bifunctional electrocatalysts. Herein, an efficient electrocatalyst consisting of controllable Ni nanoparticles (NPs) coated with ultrathin graphitic carbon shells was obtained by the pyrolysis of a Ni–Zn metal–organic framework. Intriguingly, we found that zinc vaporization not only resulted in the relatively small Ni NPs but also ultrathin carbon shells (≤3 layers). The density functional theory simulations confirmed that these ultrathin carbon shells significantly influenced electrocatalytic activity by facilitating electron transfer from the Ni core to the carbon shell. The optimized Ni1(Zn)@C demonstrated high catalytic activity for both HER and MOR, and only a low potential of 97 mV at 10 mA cm–2 was required for HER and 1.48 V at 30 mA cm–2 for MOR. In a two-electrode electrocatalytic cell measurement, a cell voltage of 1.63 V was observed at 10 mA cm–2 in the presence of methanol, 240 mV lower than that without methanol.