Heterojunction CuS@Cu2MoS4 Nanocubes for Nonenzymatic Electrochemical Glucose Sensing

Abstract

Transition-metal sulfides exhibit significant potential as catalysts in the fields of photocatalysis, sensors, and supercapacitors. In this work, heterojunction CuS@Cu₂MoS₄ nanocubes were synthesized through the strategy of template-assisted and hydrothermal approaches for nonenzymatic electrochemical glucose sensing. First, Cu₂O nanocubes (NCs) were synthesized as the template, followed by surface sulfidation to form core–shell Cu₂O@CuS NCs. Afterward, the Cu₂O core was selectively etched, followed by one-step hydrothermal growth of Cu₂MoS₄ on the CuS surface. In this way, heterojunction hollow core–shell CuS@Cu₂MoS₄ NCs were synthesized. The hollow structure can enhance mass transport and provide additional active reaction sites, while the heterostructure between CuS and Cu₂MoS₄ can amplify their synergistic effects, thereby improving conductivity and electrocatalytic activity. For analytical applications, the synthesized CuS@Cu₂MoS₄ NCs exhibit extraordinary electrocatalytic activity toward glucose oxidation. Under optimized conditions, the CuS@Cu₂MoS₄ NC-modified glassy carbon electrode demonstrates a broad linear response range from 0.002 to 23 mM for glucose determination, with a detection limit of 3.1 μM. In addition, real sample analysis reveals a recovery of 97.06–103.86%, indicating its promise for quantitative analysis in practical applications.