Biomass-Derived Carbon for Boosting Photocatalysis

To achieve the practical application of photocatalysis, various carbon materials are testified to trap photoinduced electrons (e^-) and enhance the photocatalytic efficiency of catalysts. Compared with other carbon materials, biomass-derived carbon (BDC) with sustainability and affordability is regarded as an appropriate e^- acceptor to fabricate highly active photocatalysts on a large scale. However, biomass materials exhibit significant diversity in their chemical structures and physical properties, which critically determines the morphology, composition, and physicochemical performance of the resulting BDC products. Therefore, a variety of strategies are developed to prepare highly photoactive BDC-based photocatalysts. This review summarizes a large amount of related works have been reported in the last two decades and divides the synthesis methodology into the bottom-up and top-down methods. In particular, the bottom-up method primarily employs hydrosoluble carbohydrates to synthesize four hydrothermal carbonization (HTC) composites or HTC-derived photocatalysts. As for the top-down method, the existing natural biomass precursors are utilized to fabricate three biochar-based photocatalysts. Consequently, this review comprehensively describes the designing mentality, preparation approach, architectural feature, photocatalytic application, and photocatalytic mechanism of different BDC-based materials. That will stimulate to design and develop more highly active BDC-based photocatalysts for the potential practical applications in the future.