Electrosynthesis of gold nanoparticles/porous GaN electrode for non-enzymatic hydrogen peroxide detection

A novel non-enzymatic H2O2 sensor was fabricated by electrodepositing 5–16nm AuNPs onto porous GaN electrode. The AuNPs/porous GaN sensor exhibited good sensitivity, repeatability and long-term stability towards H2O2 detection. [Display omitted] •A novel non-enzymatic H2O2 sensor was fabricated by electrodepositing 5–16nm AuNPs onto porous GaN electrode.•As far as I know, this is the first time to report porous GaN based electrochemical H2O2 biosensor.•Our work focuses on the design of simply prepared and good practicability H2O2 biosensor. There is no doubt that our work has wider societal impact. Here we report the electrodeposition of gold nanoparticles (AuNPs) onto porous GaN electrode obtained by photoelectrochemical etching planar GaN to fabricate a non-enzymatic hydrogen peroxide (H2O2) sensor. SEM images revealed porous GaN has uniformly high-porosity structure and the diameter of AuNPs is 5–16nm. The AuNPs/porous GaN electrode exhibited good electrocatalytic activity toward the reduction of H2O2 and performed as amperometric sensor for the detection of H2O2. The AuNPs/porous GaN electrode showed linear amperometric responses for H2O2 in the concentration range from 10 to 100μM with the sensitivity of 281.5μAmM−1. The limit of detection (LOD) is 2μM with a signal-to-noise ratio of 3. In addition, the AuNPs/porous GaN electrode exhibited good repeatability, reproducibility, selectivity and long-term stability for H2O2 detection, in the meanwhile, AuNPs showed excellent adhesive capacity to the porous GaN electrode, which was tested by continually sonicating the AuNPs/porous GaN electrode for 3h. Above results demonstrated this simply prepared H2O2 sensor has good practicability and is promising to measure the analyte in practical applications.