Anti-biofouling coatings with photocatalytic nanoparticles for using in marine environment

Substrates in the marine environment are quickly colonized by marine micro- and macroorganisms in biofouling process. In the past few decades, marine biofouling has become one of the pressing global problems, resulting in significant economic losses, enormous energy waste, serious security risks to marine project facilities, and harmful ecological destruction around the world. So far, the most effective methods for biofouling control are using toxic antifouling coatings on the surface of marine installations. However, almost all of these conventional antifouling paints are contaminants to the ecological environment and have a strong biotoxicity, leading to a serious marine ecological crisis. Therefore, there is an essential need to develop novel, efficient, safe, non-toxic, and environmentally friendly marine antifouling materials and techniques to prevent the harm of marine biofouling. Currently, a novel and green photocatalysis technology based on semiconductors, that facilitates the conversion of clean solar energy into chemical energy have attracted a considerable concern for its potential applications in the degradation of organic pollutants, hydrogen production from water and disinfection. To date, research has been focused on titanium dioxide (TiO2) photocatalyst for energy and environmental applications owing to its outstanding photocatalytic activity, non-toxicity, and high photostability. However, TiO2 is only sensitive under UV-light and utilizes only 4% of available solar energy, which highly restricts its potential application. Hence, there is a need to develop new strategies to improve the use of solar energy. Researchers have devoted much attention to fabricating visible-light-driven (VLD) photocatalysts. Currently, more than 150 semiconductor materials are available for environmental purification applications. Among them, bismuth-based photocatalysts such as BiVO4 due to their benefits like low cost, narrow band gap, accessibility, and stability to chemical compounds and photo corrosion get much attention. In this study, a novel visible-light-sensitive BiVO4 nanoparticles photocatalyst was synthesized through a hydrothermal method. The BiVO4 nanoparticles exhibited a perfect spherical structure. As a promising alternative for solar energy utilization, photocatalysis has been regarded as a highly efficient method to decompose organisms completely into harmless chemicals. Moreover, during the photocatalytic process, the oxidative radicals can attack the marine fouling microorganisms directly and completely, restricting the formation of biofilm on the surface of marine facilities and thus avoiding biofouling further. Therefore, there is a potential and bright prospect to apply photocatalysis technology in marine antifouling and water purification.