Hydroxyl radicals from P-C3N5 boost bacterial activity for enhanced low-temperature atrazine biodegradation

Atrazine is a widely used herbicide in global agricultural practices. However, its environmental persistence poses substantial toxicological risks to ecosystems, underscoring the need for effective remediation strategies. In this study, it is demonstrated that a hybrid system integrating the atrazine-degrading bacterium Paenarthrobacter sp. KN0901 with phosphorus-doped C3N5 significantly enhances atrazine removal efficiency under low-temperature conditions. Specifically, this hybrid system achieved a 28.0 % higher atrazine degradation rate compared with the bacterium alone, primarily by stimulating bacterial growth and upregulating metabolic activity. Further mechanistic investigations revealed that C3N5 materials increased intracellular reactive oxygen species (ROS) levels in KN0901, mainly through enhanced hydroxyl radical generation. Moreover, the hybrid system maintained stable performance across a broad range of pH and temperature conditions. Collectively, these findings provide new mechanistic insights into the role of ROS as a biochemical stimulant in biohybrid systems and offer a promising strategy for designing efficient and resilient bioremediation technologies based on material–microbe synergy.