Enhanced CO2 catalytic hydrogenation performance by H2O2-etched MoS2 nanosheets
Catalytic hydrogenation of CO2 to valuable chemicals is one of the key technologies to relieve global warming and promote the sustainable development of human society.Two-dimensional MoS2 materials have emerged as promising catalysts for CO2 activation and conversion due to their unique layered structure and adjustable S vacancies sites,which is the key active center for CO2 hydrogenation.In order to develop an efficient process for S vacancy creation,building S vacancies on MoS2 nanosheet were used as the basis for introdu-cing S vacancies on the surface using H2O2 etching method,and the reaction properties of CO2 at atmosphere and high pressure before and after H2O2 etching were compared.The results show that H2O2 etching can significantly enhance the content of S vacancies without chan-ging the crystal structure of MoS2 or affecting the chemical properties of S vacancy sites,which significantly enhances the conversion rate of CO2 catalytic hydrogenation without affecting the product distribution.Specifically,the S vacancies catalyze CO2 dissociation to produce CO at atmosphere pressure with selectivity higher than 96％,whereas they are able to catalyze the hydrogenation of CO2 to the methanol at high pressure of 5 MPa and 180℃ with high selectivity(79％).Increasing the reaction temperature improves the CO2 conversion,but the selectivity of methanol will be signifi-cantly reduced,accompanied by the generation of methane.Briefly,this work demonstrates a simple and effective method to create S vacancies on MoS2,providing theoretical and technical support for the industrial application of MoS2 cata-lysts.
万方数据
