2D gallium molybdenum selenide grown on a hollow carbon nanofibrous aerogel for high-efficiency electroreduction of nitrogen: Optimized basal plane activity via selenium vacancy modulation

Herein, a novel, Se-vacancy-modulable Ga-Mo-Se layered compound (GayMo1-ySe2-x) is synthesized by rational incorporation of two different kinds of 2D chalcogenides, i.e., transition metal dichalcogenide (MoSe2) and posttransition metal monochalcogenide (GaSe). The strained effect originating from their lattice misfit (similar to 13 %) and the electron nonequilibrium between Mo4+ and Ga2+ induce abundant Se vacancies, whose concentration can be arbitrarily modulated to optimize the basal plane activity. Moreover, a highly porous and conductive hollow carbon nanofibrous aerogel is synthesized for the first time, which serves as an ideal matrix for the in-situ growth of 2D GayMo1-ySe2-x due to integrated 3D percolation network and sufficient electrode-electrolyte contact. The unique architecture and optimized activity contribute to an advanced catalyst towards high-efficiency N-2 fixation, delivering an NH3 yield of 2.57 x 10(-10) mol s(-1) cm(-2) and a Faradaic efficiency of 26.5 % at -0.3 V vs. RHE in 0.1 M Na2SO4.

Automated summary

A novel compound with modulable Se vacancies was synthesized by incorporating two types of 2D chalcogenides, leading to enhanced catalytic activity for N-2 fixation. Additionally, a porous and conductive hollow carbon nanofibrous aerogel was synthesized for the first time, providing an ideal matrix for the growth of the compound and contributing to improved catalytic performance.