Synergistic Inorganic/Inorganic Hybrid Approach for Fabricating a BTX Gas Adsorbent with High Performance and Thermal Stability

Adsorption is an effective strategy for the removal of volatile organic compounds (VOCs), which are among the main sources of severe environmental and health issues, such as global warming and respiratory diseases, respectively. Although carbon-based adsorbents, such as activated carbon, are currently widely adopted as the most promising candidates for the removal of VOCs, their thermal instability and poor recyclability remain major issues. Here, we present the synthesis of the novel hybrid adsorbent, wherein a layered double hydroxide (LDH) is introduced into mesoporous graphene (MG). The inorganic LDH played a critical role in improving the thermal stability of the hybrid LDH@MG material in the adsorption-desorption performance of VOCs. Moreover, it blocked internal micropores that can irreversibly capture VOCs in the carbon struts, resulting in enhanced adsorption recyclability of the hybrid. In the toluene adsorption-desorption cycle experiments at high temperatures, the initial chemisorption capability showed only slight degradation during the three repeated cycles in the hybrid, while it decreased significantly to 30% in the rare MG adsorbent. These results suggest that the hybridization of LDH and MG can be an effective strategy to alleviate the structural and thermal instability of carbon-based absorbents when applied for practical industrial applications.