The integrated CO2 capture and utilization employs chemical looping approach for suppressing the equilibrium limitations of traditional gas-solid catalytic reactions, enabling efficient conversion of dilute CO2 into high-value fuels with minimal energy consumption. However, the diminishing cyclic activity of dual-functional materials poses significant challenges to their industrial application. Herein, we tailored a series of magnesium-calcium materials, the influence of coordinated metals on the cyclic performance were quantitatively investigated. Notably, Fe2Ni2Ce2Mg5Ca20CO3 achieves a cumulative CO yield of 121.0 mmol/g over 15 cycles at 650°C, with a maximum CO yield of 8.3 mmol/g per cycle and 99.0% CO selectivity, and its CO2 capture capacity remains stable at 10.6 mmol/g over 37 adsorption/desorption cycles. Experimental results indicate that lattice phase separation is a fundamental mechanism underlying the decline in cyclic activity. The strategic incorporation of transition metal intermediates promotes the formation of dispersed metal-carbonate interfaces, providing surface hydrogenation sites and accelerating the lattice decomposition and reconstruction of CO3* within a dispersed lattice. This modification mitigates the adsorption/catalytic lattice phase separation, boosts metal migration and deoxygenation activity for cyclic nanoparticle construction. The findings offer valuable strategies for designing highly efficient and stable DFMs in CO2 capture and utilization.
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