Effects of synthesis method of CaO-Ni/CeO2 dual-functional materials for integrated CO2 capture and CH4 dry reforming

Integrated CO 2 capture and dry reforming of CH 4 (ICC-DRM) is an effective approach to mitigate CO 2 emissions while producing syngas, with dual-functional material (DFM) as the core. CaO-Ni/CeO 2 DFM shows great potential for ICC-DRM application, but the impact of synthesis methods on its' structure and performance remains unclear. In this study, CaO-Ni/CeO 2 was prepared via solution combustion (SC), wet ball-milling (WM), and co-precipitation (CP), characterized by XRD, BET, SEM-EDS TEM, TGA and H 2 -TPR. The ICC-DRM performance was evaluated in a fixed-bed reactor. The SC sample exhibited the most favorable surface structure, with well-developed porosity and uniform elemental distribution, achieving the highest CO 2 capture capacity (152 wt% at 650 °C), achieving the highest CO 2 capture capacity (152 wt% at 650 °C) The WM sample showed intermediate properties, while the CP sample had a dense morphology and elemental aggregation leading to poor performance. Elevated temperature (675–700 °C) promoted WM/CP reactivity (still lower than SC at 650 °C), but caused severe performance degradation and increasing carbon deposition (21% for WM and 37% for CP after 10 cycles), while the SC sample maintained stability. Further optimization confirmed 5% Ni as the optimal loading for SC-DFM, achieving 95%–97% CH 4 conversion and a stable H 2 /CO ratio (∼1) at 650 °C. This study clarifies the regulatory effect of synthesis methods on DFM structure-reactivity relationship, identifying SC as the optimal strategy for high-performance ICC-DRM materials.