Enhanced hydrogen storage and CO₂ capture capacities on carbon aerogels from Ni-N co-doping

Carbon aerogels (CAs) has been a promising candidate for gas adsorption due to their unique attributes, but the poor surface properties and temperature reliance limit the application range. Investigations have proven that surface modification can enhance the adsorption performance. Thus, nickel and nitrogen co-doped cellulose-based carbon aerogels were synthesized by introducing nanoparticles. The outcomes demonstrate the excellent adsorption capacity and reversible adsorption/desorption features. Nickel particles improved the dissociation of hydrogen by “hydrogen spillover” effect, and interacted electrostatically with CO₂ enhanced the capture performance. Nitrogen particles enhanced the unsaturation of Ni active sites and the surface basicity, resulting a stronger interaction force with adsorbed gases. Ultimately, despite a slightly decrease in specific surface area and micropore volume, the sample exhibit the hydrogen storage capacity of 0.79 wt.% (298 K) and 7.4 wt.% (77 K), and the CO₂ capture of 17.1 mmol/g (298 K). Unique design strategy of co-doping reduced the reliance on surface area and temperature changes, and is expected to be a regular means of industrial modification of carbon materials.