Piezoelectricity Prompts Fenton Reaction Over a MoS 2 /N‐Doped Carbon‐Coated BaTiO 3 Core–Shell Heterojunction

ABSTRACT The conventional Fenton reaction has been identified as an effective approach for degrading heavy‐metal complexes; however, its practical application is hampered by issues such as iron sludge formation, low H 2 O 2 utilization efficiency, and consequently, limited degradation performance. We developed a piezocatalytic Fenton (PF) system based on a triple‐layer core–shell heterojunction (MoS 2 ‐NC@BTO) for the efficient decomplexation of Cu‐organic complexes along with the recovery of Cu 2+ . This system enables the in situ generation and subsequent activation of H 2 O 2 solely by the piezoelectric effect to produce hydroxyl radicals (•OH). The heterostructure was rationally constructed by growing MoS 2 nanosheets on an N‐doped carbon layer‐coated BaTiO 3 cubes (BTO), which facilitated decomplexation and copper recovery under ultrasonic vibration. The decomplexation rate constant of MoS 2 ‐NC@BTO (0.122 min −1 ) is 46.7 times greater than that of BTO (0.0026 min −1 ), and it achieved complete decomplexation and 92% copper recovery efficiency within 60 min. Mechanistic investigations revealed that the core–shell heterojunction promotes charge carrier separation, thereby enhancing the yield of H 2 O 2 . Meanwhile, the MoS 2 nanosheets strengthen the piezoelectric effect, enabling efficient activation of H 2 O 2 into •OH. Furthermore, the versatility and practical feasibility of the system were validated through the efficient treatment of six other Cu‐organic complexes and real effluent matrices.