Enhanced photocatalytic degradation of pharmaceutical industrial effluent using TiO₂ and N-Doped TiO₂ nanoparticles under natural sunlight: A comparative study

Despite the rapid growth of pharmaceutical industries to meet rising demand, untreated or poorly treated wastewater continues to contaminate water bodies, posing serious risks to ecosystems and human health. Conventional treatment methods often fall short in effectively addressing these complex and persistent pollutants. In this context, nanomaterials have emerged as promising candidates for advanced water purification. This study presents a novel approach by employing TiO2 and nitrogen-doped TiO2 (N-TiO2) nanoparticles, synthesized via a simple and scalable sol-gel method, for the treatment of actual pharmaceutical industrial effluent under natural sunlight, a cost-effective and sustainable condition rarely explored in previous works. The synthesized photocatalysts were thoroughly characterized using UV, XRD, SEM, FTIR, and EDX analyses. Unlike most previous studies focused on model pollutants, this work directly addresses the degradation of real pharmaceutical wastewater by combining adsorption and photocatalysis. Higher adsorption efficiencies were observed for N-doped TiO2 nanoparticles (43.77%) compared to TiO2 (21.34%) after 2 hours. Photocatalytic treatment further enhanced the degradation to 57% (N-TiO2) and 22% (TiO2) after 3 hours under natural sunlight. The study demonstrates the potential of N-TiO2 as an efficient, sunlight-driven photocatalyst for practical wastewater treatment applications, highlighting its novelty and real-world applicability.