Facile synthesis of chitosan-derived maillard reaction productions coated CuFeO2 with abundant oxygen vacancies for higher Fenton-like catalytic performance

Abstract

The two shortcomings of the Fenton-like catalyst delafossite-type oxide (CuFeO2) lie in its spontaneous agglomeration and deactivation under neutral working pH. To remedy these drawbacks, novel Fenton-like catalyst chitosan-derived maillard reaction productions coated CuFeO2 with abundant oxygen vacancies (OV–CuFeO2@MRPs) was synthesized by hydrothermal method with no extra chemical reducing agent. The systemic characterization illustrated that richer oxygen vacancies and higher particles dispersion of OV-CuFeO2@MRPs contributed to better Rhodamine B (RhB) degradation under neutral pH compared to pure CuFeO2. Cooper antisite defects in OV-CuFeO2@MRPs were evidenced by X-ray powder diffraction (XRD), fourier transform infrared spectrometer (FTIR), Raman spectra and energy dispersive X-ray spectrometer (EDX) linescan. To keep the charge balance, OV-CuFeO2@MRPs should form rich oxygen vacancies, which was confirmed by X-ray photoelectron spectroscopy (XPS) and solid-state electron paramagnetic resonance spectrometer (solid-state EPR). Furthermore, the electrochemical impedance spectroscopy (EIS) analysis revealed that oxygen vacancies could improve the electron transfer. Scavenging experiments and electron spin resonance spectroscopy (ESR) analysis demonstrated that OH was main active radical during Fenton-like reaction, and the density functional theory (DFT) calculation verified that the oxygen vacancy could effectively adsorb H2O2 and elongate O–O bond of H2O2, thus promoting the activation of H2O2 into OH.