Environmentally friendly self-assembly strategy to fabricate novel S and O co-doped carbon nitride aerogel photocatalyst with improved photocatalytic degradation capability

A novel S and O co-doped g-C3N4 aerogel (remarked as SOCNA) photocatalyst is devised and fabricated via hydrothermal shearing combined with self-assembly strategy without applying any cross-linking reagents and harmful solvents but water. SOCNA with different morphologies and O doping amounts are explored by adjusting hydrothermal time, and further the shearing and assembly mechanisms of SOCNA are elucidated. SOCNA not only displays superior removal efficiencies for the colored dyes methylene blue (97.66 %, 15 min) and rhodamine B (96.43 %, 30 min), but also the degradation rate of colorless tetracycline hydrochloride reaches as high as 92.22 % within 40 min. The influence of different concentrations and pH values of the liquids on the photodegradation efficiencies of three pollutants by using SOCNA is systematically discussed. Compared with ordinary g-C3N4, the strengthened photocatalytic activity of SOCNA can be attributed to large surface area, more charge and mass transfer channels, regulating the energy band structure via S and O doping, broadening the spectral capture range and prolonging the life of photo-induced carriers. Besides, the degradation cycle measurements of three pollutants reveal that SOCNA holds recyclable stability. Hence, the study offers an efficient and environmentally friendly strategy for the development of other heteroatom co-doped aerogel photocatalysts.