Enhanced Spin-Engineering Photothermoelectric–Enzymatic Catalysis System via Lattice Mismatch-Induced Jahn–Teller Distortion for Tumor Therapy

Abstract Oxygen-dependent electrodynamic therapy is hindered by electron–hole recombination and hypoxia. This study provides a heterojunction-induced Jahn–Teller distortion-enhanced spin-engineering Fe 3 O 4 –Ag 2 S nanoplatform to address these limitations. The large interfacial lattice mismatch induces previously unrecognized Jahn–Teller distortions on high-spin Fe sites, modifying d-orbital splitting and enhancing spin-polarized catalytic activity. This lattice–spin–carrier coupling synergistically amplifies catalase-, peroxidase-, and glutathioneox-like pathways. Under near-infrared irradiation, the photothermal effect of Fe 3 O 4 activates the thermoelectric response of Ag 2 S and drives continuous hot-carrier injection. Thermoelectric fields drive hot holes to boost catalase activity through Jahn–Teller effect-enhanced spin catalysis sites and drive hot electrons to convert O 2 to cytotoxic O 2 . − and 1 O 2 under the Jahn–Teller distortion, promoting and forming a self-amplifying catalytic loop. Fine structure characterization and density functional theory calculations collectively verify strain-driven Fe–O bond differentiation and spin-state reconfiguration. The heterojunction achieves potent thermoelectric–enzyme co-catalysis with 95% tumor inhibition under near-infrared irradiation and supports dual-mode imaging. This work establishes a framework for designing high-performance photothermal–thermoelectric catalysts through crystal field/spin-state modulation in p–n heterojunctions, synergistically boosting multi-enzyme activity and catalytic efficiency for hypoxia-resistant therapy