PEDOT-Modified Double-Layer Ni/Cobalt Hydroxide for Enhancing the Detection of H₂O₂ in Human Sweat

In order to design an electrochemical sensor for real-time monitoring of the hydrogen peroxide (H2O2) concentration level in human sweat, a sensitive electrochemical sensor based on double-layer Ni–Co(OH)2 decorated carbon cloth (CC) with a PEDOT sensitization layer (CC/Ni–Co(OH)2/Ni–Co(OH)2@PEDOT (CNNP)) has been constructed. By increasing the active surface area (13.806→43.820 cm2) and making it easier for reactant molecules to adsorb and desorb, this special double-layer Ni–Co(OH)2 interface improves the conductivity and hydrophilicity of the CNNP composite. PEDOT was chemically combined (with Ni–C) to coat the surface of the double-layer Ni–Co(OH)2 decorated carbon cloth composite, in order to prevent Ni–Co(OH)2 from detaching from the CC surface. The sensitivity, limit of detection, and linear detection range of the CNNP composite are 6.6736 mA mM–1 cm–2, 38.2 nM, and 0.0332–15.936 mM, respectively. Furthermore, the sensor constructed using the CNNP composite as the sensitive unit successfully detected the H2O2 content in human sweat. This work presents a possible synthetic approach for the composite for noninvasive health monitoring and illness diagnostics.