Sustainable Energy Laboratory, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China.
College of Chemistry, Chemical Engineering and Material Science, Zaozhuang University, Zaozhuang 277160, Shandong, China.
J Colloid Interface Sci. 2023 Apr;635:23-31. doi: 10.1016/j.jcis.2022.12.085. Epub 2022 Dec 23.
Practical structural design and electronic regulation are significant for synthesising efficient electrocatalysts. Therefore, a facile soft-template approach has been applied to successfully grow Ni/MoC heterojunction nanosheet arrays on nickel foam (NF) skeleton (NS-Ni/MoC@NF) using polyvinylpyrrolidone (PVP) as a soft template. The density functional theory (DFT) calculations reveal that abundant Ni/MoC heterojunction in NS-Ni/MoC@NF can provide many active sites with a moderate hydrogen adsorption free energy (ΔG, 0.037 eV). Benefiting from this nanosheet array structure and abundant Ni/MoC heterojunctions, the NS-Ni/MoC@NF catalyst can efficiently catalyze HER, especially at large current densities. As a result, only 151 and 271 mV overpotentials are needed to deliver 100 and 1000 mA/cm HER, respectively. More importantly, the hydrogen production testing with NS-Ni/MoC@NF as the working electrode can run stably for 500 h without activity decay under the current density of 500 mA/cm commonly used in industrial water electrolyzers, indicating that NS-Ni/MoC@NF has broad application prospects.
实用的结构设计和电子调控对于合成高效的电催化剂至关重要。因此，我们采用了一种简便的软模板法，成功地在泡沫镍（NF）骨架上生长出 Ni/MoC 异质结纳米片阵列（NS-Ni/MoC@NF），其中使用了聚乙烯吡咯烷酮（PVP）作为软模板。密度泛函理论（DFT）计算表明，NS-Ni/MoC@NF 中丰富的 Ni/MoC 异质结可以提供许多具有适度氢吸附自由能（ΔG，0.037 eV）的活性位点。得益于这种纳米片阵列结构和丰富的 Ni/MoC 异质结，NS-Ni/MoC@NF 催化剂能够高效地催化 HER，特别是在大电流密度下。结果表明，分别只需要 151 和 271 mV 的过电势即可提供 100 和 1000 mA/cm2 的 HER。更重要的是，在工业水电解槽常用的 500 mA/cm2 电流密度下，以 NS-Ni/MoC@NF 作为工作电极的制氢测试可以稳定运行 500 小时而没有活性衰减，这表明 NS-Ni/MoC@NF 具有广阔的应用前景。
