Nitrogen-doped graphene aerogels with rational indium hydroxide decoration for highly efficient photocatalytic of p-nitrophenol

One of the key challenges in photocatalysis is the suppression of electron-hole pairs' recombination, which reduces the photocatalytic degradation efficiency of promising materials. In this study, a novel heterostructured photocatalyst (In(OH)(3)/NGAs) was synthesized by coupling indium hydroxide (In(OH)(3)) with nitrogen-doped graphene aerogels (NGAs). A comprehensive evaluation of the photocatalytic degradation performance of In (OH)(3)/NGAs was conducted using para-nitrophenol (p-NP) as a model pollutant under visible light. Results show that impressive photocatalytic activities of In(OH)(3)/NGAs are mainly due to their strong synergistic effects of the heterojunction formed between In(OH)(3) and NGAs, and the active nitrogen doping of GAs. The synergistic effects result in a sizable bandgap and thus enhance the visible light absorption capability. The favorable formation of photo-generated holes and hydroxyl radicals is responsible for the efficient photocatalytic degradation of p-NP, leading to 98% removal of total organic carbon. Additionally, a comparative evaluation of the photodegradation performance of In(OH)(3)/NGAs with that of another indium-based heterostructured material (In2O3/g-C3N4 (graphitic carbon nitride) shows the superior performance of the former photocatalyst which is attributed to its unique molecular configuration and chemical bonds. This work reveals how a rational combination of NGAs with In(OH)(3) can lead to efficient photocatalytic degradation of recalcitrant organic pollutants such as p-NP.