Meng Linghu, Kao Cheng-Wei, Wang Zhen, Ma Jun, Huang Peifeng, Zhao Nan, Zheng Xin, Peng Ming, Lu Ying-Rui, Tan Yongwen
College of Materials Science and Engineering, State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle Body, Hunan University, Changsha, 410082, Hunan, China.
National Synchrotron Radiation Research Center, Hsinchu, 300092, Taiwan.
Nat Commun. 2024 Jul 17;15(1):5999. doi: 10.1038/s41467-024-50499-3.
Electrocatalytic alkynes semi-hydrogenation to produce alkenes with high yield and Faradaic efficiency remains technically challenging because of kinetically favorable hydrogen evolution reaction and over-hydrogenation. Here, we propose a hierarchically nanoporous CuAu alloy to improve electrocatalytic performance toward semi-hydrogenation of alkynes. Using Operando X-ray absorption spectroscopy and density functional theory calculations, we find that Au modulate the electronic structure of Cu, which could intrinsically inhibit the combination of H* to form H and weaken alkene adsorption, thus promoting alkyne semi-hydrogenation and hampering alkene over-hydrogenation. Finite element method simulations and experimental results unveil that hierarchically nanoporous catalysts induce a local microenvironment with abundant K cations by enhancing the electric field within the nanopore, accelerating water electrolysis to form more H*, thereby promoting the conversion of alkynes. As a result, the nanoporous CuAu electrocatalyst achieves highly efficient electrocatalytic semi-hydrogenation of alkynes with 94% conversion, 100% selectivity, and a 92% Faradaic efficiency over wide potential window. This work provides a general guidance of the rational design for high-performance electrocatalytic transfer semi-hydrogenation catalysts.
由于动力学上有利的析氢反应和过度氢化，电催化炔烃半氢化以高产率和法拉第效率生产烯烃在技术上仍然具有挑战性。在此，我们提出一种分级纳米多孔铜金合金，以提高对炔烃半氢化的电催化性能。通过原位X射线吸收光谱和密度泛函理论计算，我们发现金调节了铜的电子结构，这可以从本质上抑制H结合形成H，并削弱烯烃吸附，从而促进炔烃半氢化并阻碍烯烃过度氢化。有限元方法模拟和实验结果表明，分级纳米多孔催化剂通过增强纳米孔内的电场，诱导出富含K阳离子的局部微环境，加速水电解以形成更多H，从而促进炔烃的转化。结果，纳米多孔铜金电催化剂在宽电位窗口内实现了炔烃的高效电催化半氢化，转化率为94%，选择性为100%，法拉第效率为92%。这项工作为高性能电催化转移半氢化催化剂的合理设计提供了一般性指导。
