Destruction of a Copper Metal-Organic Framework to Induce CuPt Growth as a Heterojunction Catalyst for Hydrogen Peroxide Sensing

Abstract

Assembling bimetallic alloys (BAs) with metal-organic frameworks (MOFs) to form heterojunctions has emerged as a promising strategy for the construction of highly active electrocatalysts. However, the current approaches to prepare BA@MOF heterojunctions suffer from poor controllability. In this work, a fascinating method involving partial thermal reduction and galvanic replacement to induce CuPt growth on a CuHHTP MOF (HHTP=2,3,6,7,10,11-hexahydroxytriphenylene) is reported in order to construct a CuPt@CuHHTP heterojunction. The size of the CuPt nanoparticles can be effectively regulated by modifying the reduction temperature. The resultant CuPt NP@CuHHTP heterojunction nanoarrays exhibit high electrocatalytic activity and potential as an electrochemical H₂ O₂ sensor with a low detection limit (5 nM), high sensitivity (6.942 mA ⋅ mM^-1 ⋅ cm^-2 ), and outstanding selectivity. This in situ approach provides not only new insights into the preparation of BA@MOF-based heterojunctions but also an effective approach for the optimization of the catalytic performance of MOFs and related materials.

Keywords: H2O2 sensing; bimetallic alloys; heterojunction; in situ reduction; metal-organic frameworks.