Self-assembled Fe-CaO bifunctional materials with nickel foam template for CO2 capture and in-situ conversion

The capture and catalytic performance in integrated CO₂ and utilization (ICCU) potentially contributes to reduce CO₂ emissions with low cost and high efficiency. Breaking through the limitations of conventional dual-functional materials (DFMs). Herein, Fe-CaO/NF self-assembled with nickel foam (NF) as template is designed and prepared via hydrothermal method. CaO is anchored on the Ni-foam skeleton, and Fe-Ni bimetallic sites within the CaO matrix establishes dual-active centers synergizing CO₂ chemisorption and activation. The stability and activity stability of CO₂ capture and in-situ conversion were improved, CO₂ capture capacity is 12.8 mmol/g, CO yield is 9.33 mmol/g, ∼80 % CO₂ conversion is achieved, and 100 % CO selectivity is obtained. It shows good cycle stability and high activity in 12 cycles. The synergistic effect of Fe and Ni on CO₂ adsorption and conversion was confirm by DRIFTS. The interaction between CaO and Fe is weakened by Ni, while the interaction with Fe promotes the conversion of CO₂. In comparison, the stability and activity of the without O₂-containing cycle are higher than those of the O₂-containing. O₂ has a negative effect, leading to competitive adsorption between CO₂ and H₂O in the CO₂ capture process. The H₂O molecular layer is formed on the surface of the rod-like structure, and the reduction of the active phase is interference, resulting the regeneration of CaO was decline.