Abstract: Amid the global drive for carbon neutrality, the conversion of CO2 into methanol with green hydrogen is of great importance. Herein, we report a comprehensive study on MoS2-based catalysts and their modification for this reaction. First, the effects of different Mo and S precursors as well as hydrothermal conditions on catalytic performance were systematically screened. The optimal catalyst prepared from ammonium tetramolybdate and thiourea at 190 °C delivered a CO2 conversion of 13.7% with an exceptional CH3OH selectivity of 82.0%. Subsequent modification revealed that the introduction of Zn significantly boosts CO2 hydrogenation activity. The 1% Zn/MoS2 catalyst exhibited the best performance, achieving 14.8% CO2 conversion and 90.5% CH3OH selectivity. Over 150 h on-stream, the CO2 conversion remained stable, while CH3OH selectivity gradually increased and then plateaued. Characterization results showed that the hydrothermally synthesized MoS2 possessed an average layer number of ~5.5, indicative of few-layered nanosheets. The incorporation of Zn not only enhanced H2 activation, thereby raising CO2 conversion, but also generated additional sulfur vacancies that beneficial for the methanol formation. These findings provide crucial guidance for the rational design of robust catalysts with simultaneously high activity, selectivity and stability for conversion of CO2 to methanol.

Key words: Carbon dioxide hydrogenation, Methanol synthesis, Molybdenum disulfide catalyst, Modified by Zn