(231b) General Descriptors for Steering CO2-Assisted Selective C?H/C?C Bond Scission in Ethane

The selective C─H/C─C bond scission in CO₂-assisted alkane activation represents an opportunity for simultaneously upgrading greenhouse gas CO₂ and light alkanes for the synthesis of value-added syngas, olefins, aromatics and oxygenates. Here, Pd bimetallic (PdM_x)-derived catalysts were investigated for ethane-CO₂ reactions by combining kinetic analysis, in situ characterization and density functional theory (DFT) calculations. Two types of catalyst structures were identified under reaction conditions, with the PdCo_x alloy surface favoring ethoxy formation, a critical precursor for further C─C bond scission, and the reaction-induced InO_x/Pd interface promoting C─H bond scission. Our results revealed a general strategy to capture the reaction-induced surface configurations and in turn control the selectivity in C─C/C─H bond scission over PdM_x-derived catalysts, featuring the interplay of two general descriptors: formation energy of PdM_x surfaces and their binding energy to oxygen. Our study provides insight into the rational design of selective catalysts for light alkane-CO₂ reactions.