Novel synthesis of magnetic, porous C/ZnFeO photocatalyst with enhanced activity under visible light based on the Fenton-like reaction.

Magnetic visible-light-driven photocatalyst, porous C/ZnFeO (denoted as C/ZFO-CE) was fabricated via a CO-mediated ethanol route. CO-mediated ethanol route largely mitigated the solvent strength and facilitated the homogenous deposition of ZnFeO (ZFO) through the coordination of metallic cation with CO and HCO anions, which were hydrolyzed from CO and HO, thereby avoiding additional precipitant. Moreover, the HCO, CO and NO in the system acted as templates for the formation of porous C avoiding the additional organic mesoporous templates, thus reducing the synthesis cost. For the degradation of RhB and phenol, the C/ZFO-CE system in presence of minute HO exhibited remarkably improved catalytic performance compared with the systems of HO, ZFO, C/ZFO-CE, C/ZFO-E (C/ZnFeO synthesized in pure ethanol) and C/ZFO-E in the presence of minute HO. Furthermore, 2.0 mL of HO (30%) combined with C/ZFO-CE obtained the maximum degradation efficiencies of 100% for RhB within 60 min and 91% for phenol within 120 min. The high efficiency for degradation of pollutants over C/ZFO-CE catalyst in the presence of minute HO was possibly attributed to the strong harvest of visible light, the improved separation efficiency of the photoinduced charges and the overall ˙OH production by the "photo-Fenton" process. The existence of ˙OH during photodegradation process was evidenced via the PL-TA (photoluminescence-terephthalic acid) technique, ESR spectra and trapping experiments of active species using different scavengers. Furthermore, a possible reaction mechanism involving the Fenton-like reaction for the photodegradation of pollutants is proposed based on the experimental results.