CO2加氢合成甲醇是应对全球气候变化的有效措施,也是化学固定CO2的重要途径。在这项工作中,以葡萄糖为碳源,通过原位热解制备了碳约束的MoSe2(MoSe2@C)催化剂。与MoSe2和MoSe2/C比较了CO2加氢制甲醇的物理化学性质和催化性能。结构表征的结果表明MoSe2显示出很少的层和小的粒径。由于Mo2C-MoSe2异质结和原位碳掺杂的协同作用,在前驱体中具有合适的C/Mo摩尔比的MoSe2@C在由CO2加氢合成甲醇中显示出优异的催化性能。在最佳催化剂MoSe2@C-55下,在优化的反应条件下,甲醇的选择性达到93.7%,CO2转化率为9.7%。在100h的连续反应过程中,其催化性能保持不变,没有失活。原位扩散红外傅里叶变换光谱研究表明,甲酸盐和CO是CO2加氢制甲醇的关键中间体。
The synthesis of methanol from CO2 hydrogenation is an effective measure to deal with global climate change and an important route for the chemical fixation of CO2. In this work, carbon-confined MoSe2 (MoSe2@C) catalysts were prepared by in situ pyrolysis using glucose as a carbon source. The physico-chemical properties and catalytic performance of CO2 hydrogenation to yield methanol were compared with MoSe2 and MoSe2/C. The results of the structure characterization showed MoSe2 displayed few layers and a small particle size. Owing to the synergistic effect of the Mo2C-MoSe2 heterojunction and in situ carbon doping, MoSe2@C with a suitable C/Mo mole ratio in the precursor showed excellent catalytic performance in the synthesis of methanol from CO2 hydrogenation. Under the optimal catalyst MoSe2@C-55, the selectivity of methanol reached 93.7% at a 9.7% conversion of CO2 under optimized reaction conditions, and its catalytic performance was maintained without deactivation during a continuous reaction of 100 h. In situ diffuse infrared Fourier transform spectroscopy studies suggested that formate and CO were the key intermediates in CO2 hydrogenation to methanol.