Herein, sulfur vacancies in magnetic greigite (SVs-Fe3S4) nanosheets were synthesized by a one-step solvothermal method by adjusting the ethylene glycol: water ratio. Electron paramagnetic resonance spectroscopy (EPR) and X-ray photoelectron spectroscopy (XPS) revealed that SV-rich Fe3S4 and SV-poor Fe3S4 were acquired using 100% ethylene glycol and 100% water as solvent, respectively. A peroxidase-like activity assay demonstrated that maximum reaction rates for H2O2-mediated oxidation of 3,3',5,5'-tetramethyl-benzidine (TMB) catalyzed by the SV-rich Fe3S4 was 2.3 times higher than SV-poor Fe3...
