Internal electric field modulated BiOI nanoparticle/Bi2W0.25Mo0.75O6 microspheic p-n heterojunctions assisted by persulfate activation for enhancing simulated-sunlight-driven BPA degradation and toxicity reduction

•BiOI/Bi2W0.25Mo0.75O6 p-n heterostructure shows a hierarchical flower-like structure.•BiOI/Bi2W0.25Mo0.75O6/PDS system exhibited a synergistic effect in BPA degradation.•Degradation mechanism of BPA was proposed by DFT calculation and LC-MS analysis.•TOC and toxicity experiment proved the toxicity reduction of photocatalytic process.