DBD-coupled highly dispersed Ni/SiO2 materials for CO2 reduction performance and mechanism study

Climate warming caused by the yearly rise of CO2 emissions has posed a great challenge to the survival and development of human beings. In this study, the active component Ni was combined with mesoporous silica (SiO2) to construct a highly dispersed Ni composite silicon-based catalyst (Nix/Si), which was introduced into the dielectric barrier discharge (DBD) system for the conversion of CO2. The XRD and FTIR analyses confirmed that Ni was successfully introduced into the SiO2 carrier and the SEM results showed that the Ni elements were uniformly distributed. BET and TGA results revealed large specific surface area, stable mesoporous structure, and high thermal stability of the prepared Nix/Si. Further investigation of DBD-coupled Nix/Si performance for CO2 conversion showed significant variations based on different Ni loadings, with optimal CO2 conversion rate, CO yield, and energy efficiency achieved at 3% Ni loading, which increased by 121.8%, 101.5%, and 102.4% respectively compared to the SiO2 support. During the process of reducing CO2, the combination of Nix/Si and DBD exhibited synergistic effects, with Ni0 playing a crucial role in the CO2 reduction. The introduction of Nix/Si enhances charge transfer in the discharge region, improves CO2 adsorption, and reduces the dissociation energy of CO2 bonds. The DBD-coupled Nix/Si developed by this study offers several advantages including low energy consumption, simple operation, and high efficiency, making it a promising solution for CO2 treatment.