A heterojunction-redox catalysis strategy is proposed for fabricating a dual-functional catalyst/adsorbent to realize integration of high-temperature CO2 capture and in situ conversion.

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The integrated CO2 capture and conversion (iCCC) technology has been booming as a promising cost-effective approach for Carbon Neutrality. However, the lack of the long-sought molecular consensus about the synergistic effect between the adsorption and in-situ catalytic reaction hinders its development. Herein, we illustrate the synergistic promotions between CO2 capture and in-situ conversion through constructing the consecutive high-temperature Calcium-looping and dry reforming of methane processes. With systematic experimental measurements and density functional theory calculations, we reveal that the pathways of the reduction of carbonate and the dehydrogenation of CH4 can be interactively facilitated by the participation of the intermediates produced in each process on the supported Ni–CaO composite catalyst. Specifically, the adsorptive/catalytic interface, which is controlled by balancing the loading density and size of Ni nanoparticles on porous CaO, plays an essential role in the ultra-high CO2 and CH4 conversions of 96.5% and 96.0% at 650 °C, respectively.

Temperature swing adsorption (TSA) has great potential for CO 2 capture. However, the limited energy efficiency and time-consuming procedure have impeded its applications. Herein, we provide a promising solution by in situ electromagnetic induction heating for TSA-based CO 2 capture (EMIH-CO 2 -TSA). The magnetic adsorbents are fabricated by growing magnetic Fe 3 O 4 nanoparticles in N-doped porous carbon (NPC). With a large surface area, N doping, and highly dispersed Fe 3 O 4 nanoparticles (less than 50 nm), the obtained Fe 3 O 4 /NPC-15 exhibits a high CO 2 adsorption capacity of 2.64 mmol g −1 at 1 bar, a saturation magnetization of 15.51 emu g −1 , and an average heat capacity of 1.71 J g −1 K −1 . Using the optimized fixed target temperature heating mode on the self-established EMIH device, Fe 3 O 4 /NPC-15 exhibits an excellent EMIH-CO 2 -TSA performance, where the CO 2 desorption rate and the energy efficiency are as high as 3.27 mg g −1 s −1 and 79.2%, respectively, at 110 °C and 1 bar, surpassing the trade-off between them. Being the accurate controllable target-heating characteristics, the energy efficiency of EMIH-CO 2 -TSA is much better than that of the conventional convective-heat-transfer TSA, which provides a promising alternative technology for CO 2 capture.