MXene-supported stable adsorbents for superior CO2 capture

Polyamine-based solid adsorbents are promising candidates for CO2 capture, but long-term stability under practical regeneration conditions (100% CO2 at 120 °C) remains the biggest hurdle. In this paper, we prepared MXene-supported adsorbents with excellent long-term stability by combining two strategies. First, 1,2-butylene oxide (BO) with an epoxy group was grafted onto polyethyleneimine (PEI) to suppress the formation of urea. Second, Ti3C2(OH)x MXene was used as the support of polyamines to improve the wear resistance and thermal conductivity. The prepared MXene-supported adsorbents exhibit a large working capacity (2.6 mmol g−1) and a very stable cycling stability because of the synergetic effect. The adsorbents also exhibit a very low regeneration heat of 1.90 MJ per kg (CO2) and a high mechanical stability against attrition (0.26% after 5 h time-on-stream). Thus, these MXene-supported adsorbents make the CO2 capture process promising.