FeCu bimetallic active sites construction via hexagonal boron nitride electron regulation for high-performance electro-Fenton degradation of Rhodamine B.

The development of efficient, stable, and easily recyclable cathodes is crucial for advancing the wide application of Electro-Fenton (EF) technology. This study introduces a novel design strategy by integrating hexagonal boron nitride (h-BN) into MIL-101(FeCu) via electrospinning-carbonization techniques, yielding a self-supporting membrane electrode (HBN-FeCu-C/NFME) featuring distinctive dual-site active centers. The h-BN-mediated electronic modulation, which is validated through XAFS spectroscopy, effectively leads to the formation of Fe-B, Fe-N, and Cu-N coordination bonds. This novel configuration fundamentally reshapes the electronic structure of the bimetallic Fe and Cu system. KPFM measurements reveals a significant reduction in the surface potential to 0.521 V upon h-BN integration, correlating with enhanced interfacial electron transfer kinetics. This structural optimization endows the electrode with exceptional Rhodamine B (RhB) degradation efficiency (97.6 % within 10 min), along with outstanding stability. DFT calculations and LC-MS analysis further clarify that h-BN-induced electronic tuning directs the attack of hydroxyl radials (·OH) and singlet oxygen (1O2) to specific RhB sites, uncovering a stepwise degradation pathway mechanism from dechlorination to mineralization. Moreover, the fabricated membrane electrode exhibits promising potential for practical application in real wastewater treatment. This work presents an h-BN-mediated electronic modulation strategy for designing high performance and durable self-supporting membrane electrodes for advanced environmental remediation.