High capture capacity of CO2 in a nickel intercalated Ti3C2Tx MXene–fluorohectorite clay heterostructure

Abstract

Carbon dioxide (CO₂) capture under elevated pressure conditions is of particular relevance for pre-combustion capture and syngas purification processes. Here, we report CO₂ adsorption in a nickel-intercalated titanium carbide Ni–Ti₃C₂T_x MXene–fluorohectorite clay heterostructure, designed to modify the high-pressure adsorption behavior characteristic of pristine MXenes. The heterostructure exhibits a CO₂ adsorption capacity of 1.909 mmol g⁻¹ at 50 bar and retains measurable uptake upon pressure release, with 0.602 mmol g⁻¹ remaining at 1 bar after desorption. These results indicate that MXene–clay heterostructures are promising candidates for high-pressure CO₂ separation, while also providing a platform for future exploration of CO₂ conversion strategies beyond the scope of the present study.