Synthesis of BiOI/ZnFe2O4-Metal-Organic Framework and g-C3N4-Based Nanocomposites for Applications in Photocatalysis

A novel binary BiOI/ZnFe2O4 (BZ) with p-nn heterojunction based on the different metal-norganic framework (MOF) MIL-88B(Fe) and graphite carbon nitride (g-C3N4) as substrates has been designed. As-nprepared ternary nanocomposites have been first obtained via a simple hydrothermal system and subsequently deposited onto the MOF and g-C3N4 substrates. The photoactivity of the ternary nanocomposites was evaluated by organic pollutants degradation under LED light. These characterization results indicated that BiOI as a p-ntype semiconductor was well deposited on the surface of ZnFe2O4 (n-ntype semiconductors). The p-n heterojunction photocatalyst (BZ) improved the valence band potential of ZnFe2O4 and enhanced the removal efficiency compared to the ZnFe2O4 and BiOI. The electron-accepting and transporting properties of MOF and g-C3N4 have illustrated the excellent suppression of the recombination of e(-)/h(+) pairs thereby promoting organic dye degradation. On the basis of the electrical analysis (EIS) and photocurrent, it can be found that the enhanced charge carrier transfer of g-C3N4 correlates with the photoactivity. The results showed that O-center dot(2)- and (OH)-O-center dot as reactive oxygen species have a key role in the toxic dyes and phenol decomposition under LED light.