CuNP-TiO2-(OH)CNTs催化CO2电合成碳酸二甲酯OA

Objective Although anatase TiO2 is known for its abundance and tunable defect structure,it is widely believed that its poor electrical conductivity and low selectivity for multi-carbon products limit its application in the electrocatalytic synthesis of multi-carbon products from CO2.To overcome this perceived limitation,this study successfully reconstructed TiO2 into an efficient composite system for the electrocatalytic synthesis of dimethyl carbonate(DMC)from CO2 through a strategy combining lattice regulation,interfacial electronic coupling,and carbon nanotube synergy.Method The lattice structure and oxygen vacancy concentration TiO2 were precisely controlled via heat treatment at 500℃,providing anchoring sites for small-sized copper clusters.Hydroxylated carbon nanotubes((OH)CNTS)were introduced to construct a three-dimensional conductive and mass transport network,synergistically optimizing electron transport and mass diffusion.Furthermore,the electronic metal-support interaction(EMSI)was induced via Cu-O-Ti interfacial coordination,forming Cu5+-OV-Ti3+electronic synergistic sites.Result Comprehensive characterizations including aberration-corrected electron microscopy,synchrotron-based XANES/EXAFS,and DFT calculations confirm that the EMSI effect not only reduces the formation energy barrier of the key CO2 reduction intermediate *COOH(from 2.36 eV to 2.05 eV)but also moderately weakens the adsorption strength of the methanol activation intermediate *OCH3(from 0.71 eV to 0.52 eV),achieving precise temporal matching of the multi-step reaction.Electrochemical tests demonstrate that under optimal conditions at-2.4 V(vs.Ag/AgCl),the Faradaic efficiency(FE)for DMC reaches 44.68％.After a 10-hour long-term cycling test,the performance retention exceeds 95％,with only 1.30％(by mass)copper leaching.Conclusion This work breaks the conventional perception regarding the application of TiO2-based catalysts in multi-carbon product synthesis and provides new insights for designing cost-effective copper-based catalysts and the valorization of CO2.