Surface modification of carbon black nanoparticles enhances photothermal separation and release of CO2

Carbon black nanoparticles (CB) were covalently modified to improve the photothermal regeneration of a CO2 capture nanofluid through decarboxylation. The photothermal release of CO2 addresses high energy costs associated with regenerating capture fluids. By incorporating sulfonamides on the surface of CB, we enhance the photothermal separation of CO2 from MEA by approximately 70% more than the unmodified CB. In contrast, with an anionic sulfonate on the surface, the total CO2 released fell by approximately 60%. We verified the chemical composition and structure of surface modification using complementary techniques including FT-IR, TGA, XPS, and Raman spectroscopy.