P-incorporated CuO/Cu2S heteronanorods as efficient electrocatalysts for the glucose oxidation reaction toward highly sensitive and selective glucose sensing

Abstract

Currently, tremendous efforts have been made to explore efficient glucose oxidation electrocatalysts for enzymeless glucose sensors to meet the urgent demands for accurate and fast detection of glucose in the fields of health care and environmental monitoring. In this work, an advanced nanostructured material based on the well-aligned CuO/Cu₂S heteronanorods incorporated with P atoms is successfully synthesized on a copper substrate. The as-synthesized material shows high catalytic behavior accompanied by outstanding electrical conductivity. This, combined with the unique morphology of unstacked nanorod arrays, which endow the entire material with a greater number of exposed active sites, make the proposed material act as a highly efficient electrocatalyst for the glucose oxidation reaction. Density functional theory calculations demonstrate that P doping endows P-doped CuO/Cu₂S with excellent electrical conductivity and glucose adsorption capability, significantly improving its catalytic performance. As a result, a non-enzymatic glucose sensor fabricated based on our proposed material exhibits a broad linear detection range (0.02–8.2 mM) and a low detection limit (0.95 μM) with a high sensitivity of 2.68 mA mM⁻¹ cm⁻² and excellent selectivity.