Idrees, et al (2024) Silver (Ag) doped graphitic carbon nitride (g-C₃N₄)/biochar composite photocatalyst for improved photocatalytic degradation of ciprofloxacin (CIP). Results in Physics. https://doi.org/10.1016/j.rinp.2024.108071

Efforts to tackle pharmaceutical pollution in water have led researchers to develop innovative treatment methods. A recent study highlights the potential of a composite photocatalyst made from graphitic carbon nitride (g-C3N4), biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More (BC), and silver (Ag) for degrading ciprofloxacin, a widely used antibiotic that resists traditional wastewater treatment.

This composite material combines the strengths of its components: g-C3N4, a cost-effective and visible-light-active photocatalyst, and BC, a carbon-rich material derived from waste eggshells, known for its high adsorption capacity and conductivity. By doping g-C3N4 with Ag and coupling it with BC, the researchers enhanced light absorption and improved the separation of photogenerated charges—key factors for efficient photocatalytic performance.

The best-performing composite, containing 10% Ag by weight, achieved 70% degradation of ciprofloxacin under visible light in just four hours—a threefold improvement over g-C3N4 alone. The study also showed that excessive Ag doping could reduce effectiveness, highlighting the importance of balanced composition.

This approach offers a sustainable and economical solution for treating pharmaceutical pollutants. Beyond improving water quality, it addresses environmental and public health concerns, such as the spread of antibiotic-resistant bacteria. The findings open doors for further research into composite photocatalysts, leveraging waste materials like biochar to achieve cleaner, safer water.

This work showcases the role of advanced oxidation processes (AOPs) in developing next-generation solutions for water treatment.