Advancing low-carbon methane production via integrated carbon capture and in situ methanation (ICCM) by dual function materials (DFMs): Progress and prospects

Integrated carbon capture and methanation (ICCM) couples CO 2 capture with in‑situ conversion by employing dual‑function materials (DFMs) that integrate a CO 2 sorbent and a methanation catalyst in a single bed. This compact carbon-capture-and-utilisation concept offers smaller, more heat-efficient, and potentially more cost-effective CO 2 capture and conversion process compared to conventional approach. This review consolidates recent progress in ICCM with a critical emphasis on DFM design and synthesis (e.g., impregnation, co‑precipitation, sol‑gel, mechanochemical processing), structure–function relationships, and pros/cons of each DFM synthesis technique. We benchmark how composition, sorbent–catalyst proximity, and process conditions (namely temperature, pressure, gas hourly space velocity and gas impurities) influence CO 2 uptake, conversion, CH 4 selectivity, and long‑term durability under realistic conditions. Techno‑economic and life‑cycle perspectives are summarised to contextualise the roles of H 2 cost, reactor integration, and DFM lifetime. Finally, we outline key scale‑up challenges and research priorities, and propose three facets for technology commercialization outlook, including (i) DFM engineering, (ii) reactor design/configuration and (iii) technology integration.