Chen Wenyao, Liu Changwei, Lian Cheng, Yu Yaxin, Zhang Xiangxue, Qian Gang, Yang Jia, Chen De, Zhou Xinggui, Yuan Weikang, Duan Xuezhi
State Key Laboratory of Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
Department of Chemical Engineering, Norwegian University of Science and Technology, Trondheim 7491, Norway.
Fundam Res. 2022 Jul 3;4(5):1118-1127. doi: 10.1016/j.fmre.2022.06.012. eCollection 2024 Sep.
CO oxidation has been studied for more than a century; however, molecular-level understanding of its activation protocol and related intermediates remains elusive. Here, we present a unified mechanistic and kinetic picture of various electronic metal-support interactions within platinum-carbon catalysts via in situ spectroscopic/kinetic analyses and multi-scale simulations. Transient kinetic analysis and molecular dynamics simulations with a reactive force field provided a quantitative description of the competition between the oxygen association and oxygen dissociation mechanisms tuned by the interfacial charge distribution and CO coverage. Steady-state isotopic transient kinetic analysis and density functional theory calculations revealed a simultaneous shift in the rate-determining step (RDS) from O* dissociation to O* and CO* and O* and CO* association. A de novo strategy from the interfacial charge distribution to the reaction mechanism, kinetics/thermodynamics of RDS, and, ultimately, catalytic performance was developed to quantitatively map the above CO activation mechanism with an order-of-magnitude increase in reactivity. The proposed catalytic picture and de novo strategy are expected to prompt the development of theories and methodologies for heterogeneous catalysis.
一氧化碳氧化的研究已经开展了一个多世纪;然而,对其活化过程及相关中间体的分子水平理解仍然难以捉摸。在此,我们通过原位光谱/动力学分析和多尺度模拟,展示了铂-碳催化剂中各种电子金属-载体相互作用的统一机理和动力学图景。利用瞬态动力学分析和具有反应力场的分子动力学模拟,定量描述了由界面电荷分布和一氧化碳覆盖度调节的氧缔合和氧解离机制之间的竞争。稳态同位素瞬态动力学分析和密度泛函理论计算表明,速率决定步骤(RDS)同时从O解离转变为O与CO以及O与CO*缔合。我们开发了一种从界面电荷分布到反应机理、RDS的动力学/热力学,最终到催化性能的全新策略,以定量描绘上述一氧化碳活化机制,反应活性提高了一个数量级。所提出的催化图景和全新策略有望推动多相催化理论和方法的发展。