Single-Step Synthesis of Graphitic Carbon Nitride Nanomaterials by Directly Calcining the Mixture of Urea and Thiourea: Application for Rhodamine B (RhB) Dye Degradation

Recently, polymeric graphitic carbon nitride (g-C₃N₄) has been explored as a potential catalytic material for the removal of organic pollutants in wastewater. In this work, graphitic carbon nitride (g-C₃N₄) photocatalysts were synthesized using mixtures of low-cost, environment-friendly urea and thiourea as precursors by varying calcination temperatures ranging from 500 to 650 °C for 3 h in an air medium. Different analytical methods were used to characterize prepared g-C₃N₄ samples. The effects of different calcination temperatures on the structural, morphological, optical, and physiochemical properties of g-C₃N₄ photocatalysts were investigated. The results showed that rhodamine B (RhB) dye removal efficiency of g-C₃N₄ prepared at a calcination temperature of 600 °C exhibited 94.83% within 180 min visible LED light irradiation. Photocatalytic activity of g-C₃N₄ was enhanced by calcination at higher temperatures, possibly by increasing crystallinity that ameliorated the separation of photoinduced charge carriers. Thus, controlling the type of precursors and calcination temperatures has a great impact on the photocatalytic performance of g-C₃N₄ towards the photodegradation of RhB dye. This investigation provides useful information about the synthesis of novel polymeric g-C₃N₄ photocatalysts using a mixture of two different environmentally benign precursors at high calcination temperatures for the photodegradation of organic pollutants.