From lab to nature: Overcoming challenges in applying in-situ photocatalysis to water bodies

In-situ photocatalysis technology has become a hot research topic in the field of water treatment today due to its simple operation, environmental friendliness, and low energy consumption. This technology can not only effectively treat persistent organic pollutants in water bodies, but also remove heavy metal ions and microorganisms, thus significantly improving water quality. However, most research to date remains at the laboratory stage, and the application of in-situ photocatalysis technology in natural water bodies is still in its infancy. This paper systematically reviews the characteristics of this technology, the main factors affecting photocatalytic reactions in natural water bodies, the performance of photocatalytic reactions, the existing shortcomings, and proposes feasible ideas for future development. The paper analyzes conventional influencing factors such as light and the physicochemical properties of the water body, and discusses the impact of bottom reactants in complex natural water bodies on the overall in-situ photocatalytic reaction. The analysis of degradable water pollutants shows that this technology faces issues such as poor performance with low concentration pollutants and significant losses in reactive oxygen species (ROS) diffusion. The modification of photocatalysts, and the rational design of carriers and reactors, are key to enhancing their reactive performance. [Display omitted] •Analyzed the factors influencing the application of photocatalytic water purification technology.•Introduced the practical application of photocatalytic reactions for pollutant removal.•Discussed the promotion and inhibition relationship of substrates in natural photocatalytic reactions.•Summarized the feasibility of modified photocatalysts, photocatalyst carriers, and photoreactors.