MXene based activated carbon novel nano-sandwich for efficient CO₂adsorption in fixed-bed column

In recent decades, due to alarming increase of carbon dioxide (CO2) in the atmosphere, capturing carbon has gained an intense attention from researchers to address its adverse effect in terms of climate change. However, yet it is of utmost interest to come up with an optimum CO2 adsorbent that can substitute chemical adsorption for the future large-scale implication. In this paper, we describe the utilization of newly emerged two-dimensional (2D) nanomaterial MXenes side-by-side with activated carbon (AC) in the form of sandwich and as well as in a nanocomposite (embedded) form to evaluate their CO2 adsorption performance using a fixed-bed adsorption column. Advanced characterization of the as produced adsorbents is conducted using XRD, FTIR, HRTEM with EDX and BET analysis to elucidate their surface morphology, functional groups, chemical compositions, and properties. In the adsorption column, CO2 breakthrough measurements were performed by a continuous CO2 concentration (15 %) with an inlet flow rate at 200 mL/min at different temperatures (25-55 °C). The highest CO2 adsorption capacity (∼8.9 mg/g) was achieved by AC/MXene sandwich adsorbent at 25 °C. This corresponds to ∼37 % improvement in CO2 adsorption capacity over AC. Importantly, AC/MXene sandwich offers an excellent regeneration performance with constant CO2 adsorption capacity in regenerative cycles. Finally, the novel work with an outstanding result opens a new window of implication of emerging nanomaterials for highly efficient media large-scale CO2 capture application.