CuZr纳米颗粒对CO_(2)加氢合成甲醇的催化性能研究

Catalytic Properties of CuZr Nanoparticles on CO_(2)Hydrogenation to Methanol

CO_(2)电催化还原加氢合成甲醇是减缓CO_(2)温室效应和燃料再生的重要方式之一。采用密度泛函理论计算方法,对CuZr纳米颗粒上CO_(2)加氢合成甲醇的催化性能进行了研究。对反应物、中间物和产物在颗粒表面上的吸附能,及在反应路径“RWGS+CO-hydro”上每一步反应过程的能垒和反应能进行计算,结果表明Zr原子是所有吸附过程和反应过程的活性位点,而且CuZr纳米粒子催化活性是颗粒尺度与Zr原子在颗粒表面的掺杂位点的共同作用结果。并且在吸附能的影响上,尺度的作用大于Zr掺杂位点,而在所有反应过程中的能垒,尤其是速率限制步的能垒上,Zr原子的掺杂位点影响大于颗粒尺度。本研究进一步完善了CO_(2)加氢合成甲醇催化性能的构效关系。

The electroreduction of CO_(2)to methanol by hydrogenation is one of the important methods to decrease the greenhouse effect induced by CO_(2)and to renew fuels.The catalytic properties of CuZr nanoparticles on CO_(2)hydrogenation to methanol were researched by using the Density Functional theory calculation.The adsorption energies for the reactants,intermediates,and products,the energy barrier and reaction energy at each elementary step via'RWGS+COhydro’pathway,were calculated.It is found that all the adsorption and reaction processes are performed around Zr atom,and the catalytic activation of CuZr nanoparticles is not only related to their size,but also to Zr atom doping site.That is to say,the size role on the adsorption energies is usually larger than the role of Zr atom doping site.Zr atom doping site has greater contribution to the energy barriers,especially at the rate determining step.According to the obtained results,the relation between the catalysts’structure and the catalytic activation for CO_(2) conversion to methanol was further supported.