Pivotal copper bimetallic oxide in hierarchical Calcium magnesium materials for low-temperature carbon capture and utilization

[Display omitted] •Lowering the temperature of integrated carbon capture and utilization to syngas was investigated.•The low-temperature performance of CaO-based materials were systematically probed.•Cu, Pt, Pd on 2CaO/MgO showed outstanding CO2 capture capacity and CO conversion efficiency.•Economic D-Cu showed superior CO2 conversion rate and CO selectivity than D-Pt over cycles at 550°C.•The performance and structure stability of D-Cu are derived from bimetallic oxide Ca2CuO3. Carbon removal from anthropogenic greenhouse gas emissions is essential to achieve net-zero emissions and mitigate climate change, and integrated carbon capture and utilisation (ICCU) has been studied for subsequent in-situ chemical production. However, high temperature and CaO sintering remain critical issues, highlighting the need for improved, low-cost CO2 adsorbents that can be regenerated at lower temperatures. Herin, we innovatively introduce the low-temperature ICCU coupled with reverse water gas shift reactions (RWGS) using dual functional materials (DFMs), exemplifying a range of potential transition metals doped over CaO with or without the MgO support. Among all the prepared DFMs, D-Cu showed desirable enhanced catalytic activity at a comparatively low-temperature performance (550 °C) and still maintained a stable CO2 capture capacity (7.0 mmol g−1) and CO yield (8.0 mmol g−1) with an exceptional CO2 conversion (94.4 %) and CO selectivity (97.6 %) after cyclic hydrogenation. The mechanism study revealed that Ca2CuO3 bimetalliccatalyst in the hierarchical porous 2CaO/MgO matrix of D-Cu plays a crucial role in retaining its cyclic stability, surpassing that of noble D-Pt. Given the ICCU-RWGS performance and cyclic stability of cost-effective D-Cu at reduced operating temperatures, the findings would minimise energy and cost consumption.