An Efficient CuBi ₂ O ₄ /nZVI‐PEC/PMS System for Simultaneous Removal of OFL and Cr(VI): Synergistic Role of S‐Scheme/Ohmic Dual Junctions and Cu/Fe Double Active Centers

Abstract The synchronous removal of refractory antibiotics and toxic heavy metals from complex wastewater remains a critical environmental challenge. Herein, an efficient PEC/PMS system is designed based on the advanced CuBi 2 O 4 /TiO 2 photoanode and nZVI/TiO 2 photocathode, featuring S‐scheme/Ohmic dual junctions and Cu/Fe double active centers. This system demonstrates significantly accelerated oxidation and reduction kinetics, achieving near‐complete removal of OFL ( k = 0.994 min −1 ) and Cr(VI) ( k = 0.325 min −1 ) within 10 min. A series of advanced techniques (In situ X‐ray photoelectron spectroscopy, femtosecond transient absorption spectroscopy) and Density Functional Theory (DFT) calculations elucidate that the distinct S‐scheme junction and Ohmic junction dramatically enhance the charge separation efficiency and preserve the highest‐energy charge carriers for redox reactions. Furthermore, this facilitates the donation of electrons from the metal active centers to the peroxide bond of PMS. Notably, the activation energy barriers of CuBi 2 O 4 /TiO 2 and nZVI/TiO 2 are drastically reduced to 1.21 and −0.4 eV, respectively, and ultimately direct the reaction pathway toward a non‐radical pathway dominated by high‐valent metal‐oxo species (HVMOs). The practical application prospects (e.g., environmental adaptability and long‐term stability) are comprehensively evaluated. This study offers novel insights for constructing an efficient PEC/PMS system based on advanced dual‐photoelectrode materials to remediate complex wastewater.