Guo Ying, Wang Tairan, Yang Qi, Li Xinliang, Li Hongfei, Wang Yukun, Jiao Tianpeng, Huang Zhaodong, Dong Binbin, Zhang Wenjun, Fan Jun, Zhi Chunyi
Department of Materials Science and Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong 999077, China.
Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China.
ACS Nano. 2020 Jul 28;14(7):9089-9097. doi: 10.1021/acsnano.0c04284. Epub 2020 Jun 24.
MXene-based catalysts exhibit extraordinary advantages for many catalysis reactions, such as the hydrogen evolution and oxygen reduction reactions. However, MXenes exhibit inadequate catalytic activity for the electrochemical nitrogen reduction reaction (NRR) because they are typically terminated with inactive functional groups, F* and OH*, which mask the active metal sites for N binding. Here we modified the surface termination of MXene (TiCT) nanosheets to achieve high surface catalytic reactivity for the NRR by ironing out inactive F*/OH* terminals to expose more active sites and by introducing Fe to greatly reduce the surface work function. The optimally performing catalyst (MXene/TiFeO-700) achieved excellent Faradaic efficiency of 25.44% and an NH yield rate of 2.19 μg/cm·h (21.9 μg/mg·h), outperforming all reported MXene-based NRR catalysts. Our work provides a feasible strategy for rationally improving the surface reactivity of MXene-based catalysts for efficient electrochemical conversion of N to NH.
基于MXene的催化剂在许多催化反应中表现出非凡的优势，如析氢反应和氧还原反应。然而，MXene对电化学氮还原反应（NRR）的催化活性不足，因为它们通常被无活性的官能团F和OH封端，这些官能团会掩盖用于结合氮的活性金属位点。在这里，我们通过消除无活性的F*/OH*端基以暴露更多活性位点，并引入铁以大幅降低表面功函数，对MXene（TiCT）纳米片的表面端基进行了改性，以实现对NRR的高表面催化反应活性。性能最佳的催化剂（MXene/TiFeO-700）实现了25.44%的优异法拉第效率和2.19 μg/cm·h（21.9 μg/mg·h）的NH产率，优于所有已报道的基于MXene的NRR催化剂。我们的工作为合理提高基于MXene的催化剂的表面反应活性以实现氮到氨的高效电化学转化提供了一种可行的策略。
