BiVO₄/FeOOH semiconductor-microbe interface for enhanced visible-light-driven biodegradation of pyridine

Area of Science:

• Environmental Science
• Materials Science
• Microbiology

Background:

• Pyridine is a toxic, nitrogen-containing heterocyclic compound that is difficult to biodegrade using conventional methods.
• Developing efficient methods for pyridine degradation is crucial for environmental protection and wastewater treatment.

Purpose of the Study:

• To develop an enhanced visible-light-driven biodegradation system for pyridine using a BiVO4/FeOOH semiconductor-microbe interface.
• To investigate the efficiency of pyridine and total organic carbon (TOC) removal and ammonia nitrogen (NH4+-N) formation.
• To elucidate the underlying mechanisms of enhanced biodegradation, including electron transfer and microbial community shifts.

Main Methods:

• Fabrication of a BiVO4/FeOOH semiconductor-microbe interface.
• Visible-light-driven biodegradation experiments to assess pyridine, TOC, and NH4+-N removal.
• Electron transport system activity and photoelectrochemical analysis to study charge transfer.
• High-throughput sequencing to analyze microbial community structure.

Main Results:

• The BiVO4/FeOOH semiconductor-microbe system achieved 100% pyridine removal, 88.06% TOC removal, and 84.51% NH4+-N formation.
• Significantly improved photogenerated carrier transfer between microbes and semiconductors was observed.
• Functional microbial species involved in pyridine biodegradation and electron transfer were enriched at the interface.
• Light-excited holes were identified as crucial for pyridine mineralization.

Conclusions:

• The developed bio-photodegradation system demonstrates superior efficiency in degrading pyridine compared to standalone biodegradation or photodegradation.
• The synergistic effect between the semiconductor and microbes, facilitated by enhanced electron transfer, is key to the improved performance.
• This system presents a viable and efficient alternative for treating wastewater contaminated with recalcitrant pollutants like pyridine.