Zhao Qin, Zhang Yue, Ke Changwang, Yang Weilin, Yue Jianshu, Yang Xiaofei, Xiao Weiping
College of Science, Institute of Materials Physics and Chemistry, Nanjing Forestry University, Nanjing 210037, China.
Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), College of Chemistry, Nankai University, Tianjin 300071, China.
Nanoscale. 2024 Apr 25;16(16):8020-8027. doi: 10.1039/d4nr00020j.
The improvement of the hydrogen evolution reaction (HER) performance of nanomaterials is associated with the interfacial synergistic interaction and their hydrogen adsorption kinetics. Nevertheless, it is still a challenge to accelerate the proton transfer and optimize the HER kinetics by constructing Pt-supported heterostructures based on the hydrogen spillover phenomenon. Herein, oxygen vacancies on the surface of MXene nanosheets were constructed a high-temperature annealing method, which was employed to anchor/stabilize Pt nanoparticles and fabricate a Pt/MXene heterostructure. EPR and XPS analyses verified the presence of oxygen vacancies, which could enhance the intrinsic HER activity of the MXene. The HER catalytic performance was investigated by taking into account the surface structure of the MXene affected by the annealing temperature, the concentration of Pt and the number of deposition cycles. Electrochemical results showed that Pt/MXene with higher utilization of Pt was obtained at 900 °C and 0.05 mg mL. The 0.05-Pt/MXene-900 obtained at deposition of 60 cycles in 0.5 M HSO solution exhibited the optimized HER activity. The overpotential was 22 mV at a current density of 10 mA cm and the Tafel slope was 42.41 mV dec. Furthermore, the accelerated HER kinetics was mainly due to the electron trapping ability of the MXene, small particles of Pt, as well as the enhanced charge transfer between the oxygen vacancies of the MXene and Pt. This strategy for constructing Pt-supported heterostructures based on the vacancy anchoring effects provides new ideas for the design of well-defined electrocatalysts toward the HER.
纳米材料析氢反应（HER）性能的提升与界面协同相互作用及其氢吸附动力学相关。然而，基于氢溢流现象构建铂负载异质结构以加速质子转移并优化HER动力学仍是一项挑战。在此，通过高温退火法在MXene纳米片表面构建氧空位，用于锚定/稳定铂纳米颗粒并制备Pt/MXene异质结构。电子顺磁共振（EPR）和X射线光电子能谱（XPS）分析证实了氧空位的存在，其可增强MXene的本征HER活性。通过考虑受退火温度、铂浓度和沉积循环次数影响的MXene表面结构来研究HER催化性能。电化学结果表明，在900℃和0.05mg/mL条件下获得了铂利用率更高的Pt/MXene。在0.5M H₂SO₄溶液中沉积60个循环得到的0.05-Pt/MXene-900表现出优化的HER活性。在电流密度为10mA/cm²时过电位为22mV，塔菲尔斜率为42.41mV/dec。此外，HER动力学的加速主要归因于MXene的电子俘获能力、铂的小颗粒以及MXene与铂之间氧空位处增强的电荷转移。这种基于空位锚定效应构建铂负载异质结构的策略为设计用于HER的明确电催化剂提供了新思路。
