Metal–organic framework (MOF)-derived hollow hybrid Cu2O/Cu/Au for non-enzymatic H2O2 sensing

Abstract

The template-directed strategy is a facile and universal method to synthesize novel and useful functional materials that are difficult to achieve by traditional methods. Herein, a ternary hybrid Cu₂O/Cu/Au with a hollow structure is synthesized via a two-step template-directed strategy. Hollow Cu-MOF-74 is selected as a self-sacrificial template and calcined under an Ar atmosphere to obtain hollow Cu₂O/Cu with the preservation of the original hollow structure and rod-like shape. Then, hollow Cu₂O/Cu acts as a self-sacrificial template as well as a reducing agent. The metal precursors are adsorbed on the surface of Cu₂O/Cu and in situ reduced to Au nanoparticles, decorating the surface uniformly and forming the hollow ternary hybrid Cu₂O/Cu/Au. More importantly, hollow Cu₂O/Cu/Au is equipped with enhanced electrochemical catalytic activity toward the reduction of H₂O₂, which is ascribed to the introduction of Au nanoparticles facilitating electron transfer in the catalytic reaction, and it can be used as a candidate for an H₂O₂ sensor with high sensitivity, wide detection range and low limit of detection. Selecting suitable templates provides a new opportunity for constructing hybrids with novel structures.