Regulating the metal-support interactions by tuning the ratios between N and B based on the C2N motif to develop efficient Pd-based catalysts for CO oxidative coupling to DMO: A DFT study

Abstract

The CO oxidative coupling to dimethyl oxalate (DMO) is a crucial step in the coal to ethylene glycol, but the industrial catalysts have drawbacks: high Pd loading and low Pd utilization, dramatically increasing the cost. There is an urgent need to develop low-cost and high-performance Pd-based catalysts for the CO oxidative coupling to DMO. Given the excellent properties of the 2D materials, we used the DFT calculations to design three Pd-based catalysts based on the C2N motif to investigate their catalytic performance in the CO oxidative coupling to DMO. Since the electronegativity of Pd is between N and B, on the one hand, by adjusting the relative ratios of N and B in the support, the valence state of Pd can be transformed from the highly oxidized state to the metallic state through charge transfer between the support and Pd. On the other hand, the activities of the different CO and CC coupling can be modulated by the metal-support interactions strength, tuning the main product from dimethyl carbonate to DMO. The work provides a theoretical viewpoint by regulating the MSI and the valence state of Pd to explore the efficient Pd-based catalysts for the CO oxidative coupling to DMO.