Photocatalytic Processes for Antibiotic Degradation

The uncontrolled discharge of antibiotics into aquatic ecosystems poses serious risks to human health and microbial resistance. Photocatalytic processes offer a promising route to degrade these recalcitrant molecules under light activation. Semiconducting materials such as titanium dioxide, zinc oxide and emerging metal oxides absorb photons to generate electron–hole pairs that produce reactive oxygen species, initiating oxidative breakdown of antibiotic structures. Advances in material design have extended absorption into the visible spectrum through doping, heterojunction formation and incorporation of carbonaceous supports such as graphene. Coupling photocatalysis with Fenton-like systems further enhances radical generation and mineralisation rates. Practical applications span pharmaceutical effluent treatment to on-site water remediation, with ongoing efforts to improve catalyst stability, recyclability and energy efficiency while elucidating mechanistic pathways and minimising secondary pollution.

Research from Nature Portfolio

Recent studies have demonstrated the efficacy of tailored nanocomposites to enhance antibiotic degradation. A ternary system combining TiO₂–ZnO doped with chitosan and graphene support exhibited superior photocatalytic removal of tetracycline under UV irradiation, achieving near-complete mineralisation in three hours at acidic pH. Graphene improved charge separation and surface adsorption, enabling practical treatment of pharmaceutical wastewater. Another investigation employed tungsten trioxide as a solar-active photocatalyst for amoxicillin degradation under simulated sunlight. Through response-surface optimisation of pH, catalyst loading and antibiotic concentration, rates approaching pseudo-first-order kinetics were achieved, although mineralisation remained incomplete, highlighting opportunities for coupling with complementary oxidative processes.

Photocatalytic Processes for Antibiotic Degradation publication trend

The graph below shows the total number of articles in photocatalytic processes for antibiotic degradation across all publications each year (not limited to Nature Index journals).

Technical terms

Semiconductor photocatalyst: A material that absorbs light to generate electron–hole pairs, initiating redox reactions on its surface.

Reactive oxygen species (ROS): Highly reactive molecules such as hydroxyl radicals and superoxide anions that oxidise organic contaminants.

Band gap energy: The energy interval between valence and conduction bands in a semiconductor, determining its optical absorption range.

Adsorption: The adhesion of molecules onto a solid surface, facilitating subsequent photocatalytic degradation.

Mineralisation: Complete conversion of organic compounds into inorganic end products like CO₂, H₂O and mineral acids.

Heterogeneous Fenton-like reaction: An advanced oxidation process combining solid iron catalysts and hydrogen peroxide to generate hydroxyl radicals.

References

1. Synthesis and characterization of ternary chitosan–TiO2–ZnO over graphene for photocatalytic degradation of tetracycline from pharmaceutical wastewater. Scientific Reports (2021).
2. Tungsten Trioxide (WO3)-assisted Photocatalytic Degradation of Amoxicillin by Simulated Solar Irradiation. Scientific Reports (2019).
3. Effective photocatalytic degradation of amoxicillin using MIL-53(Al)/ZnO composite. Environmental Science and Pollution Research (2022).