Rational design of ZnFe_2O_4/g-C_3N_4 nanocomposite for enhanced photo-Fenton reaction and supercapacitor performance

摘要

The construction of heterostructure with better visible light active photocatalyst and enriched charge storage electrode material for supercapacitor has plays an important role in the field of energy and environmental remediation research. The facile sol-gel followed calcination method has been adopted to synthesize the effective heterostructure (ZnFe2O4/g-C3N4) nanocomposite. The physio chemical characteristics of the synthesized nanomaterials were examined through different analytical techniques. The heterostructure formation between ZnFe2O4 and g-C3N4 was confirmed by high resolution transmission electron microscope. Compared to the pure ZnFe2O4 and g-C3N4, the composite catalyst shows the enhanced photocatalytic activity and high electrochemical specific capacitance of 103 F/g at 10 A/g of current density due to the synergistic effect between the nanoparticles. The photocatalytic active radicals and possible reaction mechanism was demonstrated by elemental trapping experiment which shows the OH* radicals plays the major role and O-2 contribute the minor role for degradation process. The augmented capacitance of the composite electrode suggests that the improved ion diffusion rate and increased active redox site for pseudo capacitive behavior. The 95% of degradation efficiency was maintained after 5 cycles of photocatalytic activity under direct sunlight and 94% of capacitance retaining at current density of 10 A/g after 500 cycles demonstrate the stability of the composite catalyst. Hence, this heterostructure could be used as an auspicious candidate for energy and environmental remediation application for practical use.