Construction of a Ce‐UiO‐66/MCo2O4 Heterojunction for Photocatalytic Cr(VI) Detoxification Through a p‐n Junction Formation Mechanism

Abstract

AbstractHeterojunction engineering in catalyst structures is a promising approach to solve some restrictions in photocatalyst design, such as a narrow photoabsorption range and rapid recombination of photogenerated charge carriers. In this work, MCo2O4 (M=Mn, Zn, Fe) was synthesized using a template method. The porous MCo2O4 was composited by Ce‐UiO‐66 to form a heterojunction structure. The resultant material Ce‐UiO‐66/MCo2O4 had a hierarchically porous architecture and was used as a photocatalyst for Cr(VI) reduction. The coupling of Ce‐UiO‐66 and MCo2O4 resulted in a p‐n junction mechanism for charge carrier transfer. The Ce‐UiO‐66/MCo2O4 heterojunctions exhibited high Cr(VI) reduction ability under visible light irradiation over 120 min. The highest Cr(VI) photoreduction rate of the heterojunction is 14 times that of Ce‐UiO‐66. The binary heterojunction maintains high photoreduction efficiency (100 %) of Cr(VI) after four cycling tests showing excellent photocatalytic stability.