A review of photocatalysis, basic principles, processes, and materials

The industrial revolution has improved living standards while destroying the natural world, and as a result, environmental pollution has become a serious concern for both developed and developing countries. Furthermore, photocatalysis is a chemical process that uses light energy to accelerate thermodynamically demanding operations, such as photosynthesis, which makes it a viable substitute for deep solar energy storage. Reduced exposure to chemicals and toxins released into the environment by industrial activity is another great benefit of this method. First and foremost, photocatalysis allows fossil fuels to be used for other purposes by substituting low-temperature pollution removal processes with high-temperature ones. Since they may exist in numerous valences and have excellent catalytic efficiency, various photocatalytic materials such as AgCl, P-doped g-C 3 N 4 , and Z-scheme photocatalysts coupled with Fe 3 O 4 /H 2 O 2 have received interest as photocatalysts. One issue covered in the reviews is the Z-scheme strategy, which focuses on creating heterojunctions with appropriate band alignments to improve electron transport pathways and increase MnO 2 's photocatalytic activity. The review discusses the latest developments in photocatalysis, MnO2-based composites for photocatalytic capabilities, and the Z-scheme charge carrier mechanism. The electrical, photoelectric, and crystallographic properties of MnO 2 are discussed in the review article, with a focus on the relevance of the Z-scheme electron transfer pathway in augmenting photocatalytic activity. Exploring several electron transport channels in MnO 2 -based composites, various characterization approaches offer insights into the Z-scheme mechanism. Moreover, we have reviewed various Photocatalysis, basic principles, processes, and materials. • MnO 2 , AgCl, and P-doped g-C 3 N 4 , coupled with Fe 3 O 4 /H 2 O 2 in a Z-scheme, are gaining interest for their efficiency and low cost. • The Fe 3 O 4 /H 2 O 2 system enhances the Z-scheme photocatalysts through synergistic interactions. • MnO 2 , its electronic, photoelectric, and crystallographic characteristics, are discussed. • Effective use of Photo-Fenton-assisted AgCl and P-doped g-C 3 N 4 in Z-scheme photocatalysis is highlighted. • Electron transfer mechanisms in MnO 2 -based composites and their role in the Z-scheme process are discussed.