Facile Synthesis of Stable MO2N Nanobelts with High Catalytic Activity for Ammonia Decomposition

Abstract

Summary of main observation and conclusionIn the present work, high quality γ‐Mo2N catalysts for ammonia decomposition were successfully synthesized via temperature programmed nitridation of α‐MoO3 nanobelts. The optimal conditions for the synthesis of MoO3 precursors were obtained by using the orthogonal experimental method. The MoO3 precursors and the corresponding fresh and used Mo2N catalysts were characterized by various characterization techniques, including transmission electron microscopy, X‐ray diffraction and N2 adsorption‐desorption. Furthermore, temperature‐ programmed desorption by N2 or NH3 and X‐ray photoelectron spectroscopy analysis were performed to better understand the chemical properties of Mo2N catalysts. The results revealed that Mo2N catalyst has good NH3 adsorption ability and facilitates the dissociation adsorption of N2. Moreover, the morphology and structure of Mo2N catalysts well maintained after the reaction. Therefore, among the three transition metal nitrides (Mo2N, W2N and VN) and some Mo‐based catalysts previously reported, Mo2N catalysts showed very high activity and stability. Nearly 94% conversion of NH3 could be reached at 550°C with the gas hourly space velocity of 22000 cm3∙gcat–1∙h–1 and no obvious deactivation was observed during a 72 h test.