氮掺杂碳材料负载碳化钼的合成及析氢性能研究

Synthesis of molybdenum carbide supported on nitrogen doped carbon for hydrogen evolution reaction

过渡金属碳化物被认为是一类可替代贵金属的高效电催化析*氢反应催化剂,提升其催化性能和稳定性能获得了广泛关注和研究。本文以钼酸铵和二氰二胺为前驱体,均匀混合后利用一步高温退火法制备了氮掺杂碳材料负载碳化钼(Mo2C-NC)的复合材料。通过透射电子显微镜,X射线粉末衍射以及X射线光电子能谱等测试对该催化剂形貌,组成及结构进行表征。电化学测试结果表明,Mo2C-CN复合催化剂表现了优异的电催化析氢性能:当电流密度为10 mA cm^-2时,在酸性和碱性体系中,Mo2C-CN催化剂的过电势分别为和130和257 mV s^-1,并且均展示出了优异的稳定性能。

Transition-metal carbides are considered as efficient catalysts for the hydrogen evolution reaction(HER)to replace the noble metal based catalysts.Intensive concern and researches have been devoted to further improve their catalytic properties and cycling ability.In this work,the molybdenum carbide and nitrogen doped carbon(Mo2C-NC)composites were prepared via one-step annealing of ammonium molybdate and dicyandiamide precursors.The morphology,composition,and structure of the Mo2C-NC composites were characterized by transmission electron microscopy(TEM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).The Mo2C-NC composites exhibited excellent catalytic activity towards HER according to the electrochemical tests.The low overpotential of 130 and 257 mV s^-1 under the current density of 10 mA cm^-2 were achieved in acid and alkaline environment,respectively.In addition,the Mo2C-NC composites shown outstanding cycling stability in both acid and alkaline environment.