Electrocatalytic-Induced Electrochemical Sensor Based on the Heterojunction Cu–Ni/Ni(OH)2 for the Detection of Hydrogen Sulfide

The sensitive and specific analytic assay of hydrogen sulfide (H2S) is beneficial to early H2S-related disease diagnosis and prevention. Herein, an electrocatalytic-assisted electrochemical sensing platform with excellent precision is proposed to detect H2S based on heterojunction Cu–Ni/Ni(OH)2 nanoflowers by coupling the vulcanization reaction of copper ions, where a series of Cu–Ni/Ni(OH)2 nanohybrids with diverse amounts of Cu2+ ions modified on a bare electrode have been prepared via a facile ion-exchange approach. Taking advantage of the unique nanostructure, the integrated electroactive Cu–Ni/Ni(OH)2, the optimal interface effect, and the excellent specific surface area with an opportunity for high surface active sites, the designed Cu–Ni/Ni(OH)2 nanohybrids exhibit an outstanding current response. Under optimal experimental conditions, the electrochemical sensor reveals superb analysis performance with a wider linear range from 0.1 to 230 μM and a low limit of detection of 0.091 μM for H2S detection. This approach provides an avenue to synthesize copper-based hydroxide nanomaterials as a robust electrochemical indicator and an idea for highly specific detection of H2S for early disease screening and biomedical detection.