Heterojunction CuS@Cu₂MoS₄ Nanocubes for Nonenzymatic Electrochemical Glucose Sensing

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.