A Review on Effective Photocatalytic Remediation of Noxious Pollutants Utilizing Biochar Tailored Graphitic Carbon Nitride

The synthesis and production of advanced photocatalytic materials for wastewater treatment and their adequate mineralization have consistently been exciting prospects to counter worldwide pollution challenges. Recently, g-C₃N₄ (graphitic carbon nitride), a metal-free, polymeric semiconducting material with a small band gap (∼2.7 eV), has arisen as a prominent material with multitudinous applications, viz., organic synthesis, energy production and storage, environmental pollution mitigation, etc. By incorporating functional groups from biomass-derived precursors, researchers aim to tailor the surface properties of g-C₃N₄ to better suit specific pollutant types and improve its overall performance as a remediation material. Biomass is a renewable source of carbonaceous material with a wide availability of sources, low cost, and biodegradability. This review article gives a bird’s eye view of the role of biochar-based metal (un)doped g-C₃N₄ nanocomposites in photocatalysis and mineralization of hazardous pollutants such as pharmaceuticals, dyes, chromium, polyaromatics, pesticides, etc., from 2015 to now. Also, this review article paves the way for researchers to avail new ideas for further application of biochar-derived g-C₃N₄.