Microstructure regulation and enhanced VOC removal performance of carbon aerogels by surface carbon nanotube grown

Carbon aerogels were newly employed in adsorption for volatile organic compounds (VOCs) as an emerging material. In contrast, the microstructure and high carbon consumption are the primary factors restricting their application scenarios. Carbon nanotubes, recognized for their controllable cylindrical hollow structure and hydrophobic walls, generally possess higher adsorption capacities than typical carbon adsorbents. In this study, carbon nanotubes were grown on the surface of carbon aerogels using the chemical vapor deposition method by controlling different deposition conditions. The results showed that the modified samples displayed the maximum adsorption capacity of 145.0 mg/g and 178.3 mg/g for toluene and 1,2- dichlorobenzene, respectively. After ten regeneration cycles, the performance decreased by 7.9 % and 5.6 %, respectively. Meanwhile, the carbon replenishment was about 0.2 g/g, which is an excellent complement for carbon consumption. Various characterization patterns showed that deposition temperature was reflected in its deposition rate, deposition times influenced the formation of multi-walled carbon nanotubes, and deposition concentration affected the length of carbon nanotubes. This study offers valuable insight into the growth patterns of carbon nanotubes and the microscale regulation of carbon material surfaces, and this method is expected to be an effective means of carbon replenishment, carbon addition to carbon-poor materials, and enhancement of VOCs removal performance, and the growth mechanisms investigated are instructive for practical applications.