A dual-functional integrated TiO2-PPy/CF photoanode for simultaneous phenol degradation and power generation

Microbial fuel cells (MFCs) function as organic pollutant treatment systems with the unique advantage of recovering energy from waste. However, their energy recovery efficiency is often constrained when degrading toxic organic compounds. This study constructed a MFC system incorporating a TiO 2 -PPy/CF photoanode. TiO 2 with a nanoflower structure was fabricated, the loading of PPy particles on the partial surface of TiO 2 nanoflowers not only remarkably improved the MFC's power generation performance but also extended the photoresponse range of TiO 2 and efficiently suppressed the recombination of photogenerated electron-hole pairs.This electrode integrates biocatalytic and photocatalytic functions within a single structure, enabling both efficient electricity generation and phenol removal from wastewater. Under a specific solar light intensity, it achieved an impressive degradation efficiency of 77.30 % for 40 mg/L phenol within 5 h—6.1 times higher than that of the pure bacterial system (12.67 %)—thus highlighting its superior photocatalytic degradation capacity. Ultimately, with the assistance of biodegradation, the overall degradation efficiency reached 89.95 %, and the maximum power density achieved 5070 mW/m 3 . Furthermore, in contrast to the CF anode (4.32 %), the TiO 2 -PPy/CF photoanode for the first time achieved a significant increase in the abundance of Elusimicrobiota to 40.70 %, corresponding to a relative enhancement rate of ~842 % and demonstrating robust biofilm enrichment potential. Moreover, the underlying mechanism was elucidated: electron transfer is enhanced via multiple internal and external synergistic pathways, including pili and cytochromes. This work not only developed a high-performance integrated photoanode but also, critically, established a new paradigm for performance breakthroughs through the targeted modulation of functional microbial communities via electrode engineering.