Self-adaptive Ni nanoparticles in perovskite LaNi1-xAlxO3/CaO for durable CO2 capture and in-situ conversion

Abstract

Abstract Integrated CO 2 capture and conversion (iCCC) technology is promising for carbon neutrality, but the high-temperature deactivation of dual-functional materials (DFMs) limits its practicality. Herein, we develop adaptive metallic nano-catalysts via in-situ exsolution-dissolution in perovskite-based DFMs, enabling self-adjustment during cyclic CO 2 /CH 4 redox switching. Al-doping induces the Jahn-Teller distortion in LaNiO 3 perovskite, making the lattice contracted to enrich Ni 2+ and oxygen vacancies; thereby tailoring the smooth exsolution-dissolution of Ni nano-catalyst and creating fast O 2- migration channels for facilitating CO 2 adsorption. The optimized perovskite LaNi 0.8 Al 0.2 O 3 /CaO exhibits exceptional durability over 50 cycles, achieving a high CO 2 capture capacity of 10.2 mmol g DFM −1 and both high conversions of 91.5% for CO 2 and 93.5% for CH 4 . The mechanism study by the in-situ characterizations and surface energy calculations confirms that heteroatomic doping modulates the metal-support interactions, providing a solution for the long-sought deactivation problems of sintering and coking.