Marleni Wirmas, Reva Budiantono, Muhammad Haris Mahyuddin, Mohammad Kemal Agusta, Adhitya Gandaryus Saputro, Hadi Teguh Yudistira, Hermawan Kresno Dipojono
Modifying heterogeneous catalysts for supported cluster-based types is important to design catalysts with better activity, stability, and selectivity. Alloying Pd with Zn and supported by ZrO2 is a promising way to design catalysts for CO2 hydrogenation to HCOOH, but the nature of the active catalytic sites and the mechanism remain unknown. Two representative models have been investigated: subnanometer cluster Pd5Zn/ZrO2 and PdZn(101) surface. DFT calculations combined with microkinetic simulations are used to identify the optimum structure and configurations for the reaction. Compared to the PdZn(101) surface, the Pd5Zn/ZrO2 offers much more stable adsorption and formation of intermediate species. Moreover, the formate route is more likely to proceed on PdZn(101) surface from the viewpoint of thermodynamic and kinetic. In contrast, the supported Pd5Zn/ZrO2 cluster prefers the carboxyl pathway, where the interface site between cluster-support is ascribed to a far more stable configuration. Electronic structure analysis reveals the nature of the transition state on intermediate formation, particularly the role of Pd and Zn edge atoms on the selectivity towards the carboxyl pathway on Pd5Zn/ZrO2. Finally, the comparison of microkinetic simulation results shows a preference for HCOOH formation on Pd5Zn/ZrO2 than PdZn(101) surface at medium to higher temperature. © 2024 The Authors
Doctoral Program of Engineering Physics, Faculty of Industrial Technology, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40132, Indonesia; Master Program of Engineering Physics, Faculty of Industrial Technology, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40132, Indonesia; Quantum and Nano Technology Research Group, Faculty of Industrial Technology, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40132, Indonesia; Research Center for Nanoscience and Nanotechnology, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40132, Indonesia; Mechanical Engineering Study Program, Institut Teknologi Sumatera, Way Hui, South Lampung, 35365, Indonesia