3D/1D heterostructure of p-BiOBr nanoflowers modified n-TiO2 nanorod arrays for highly sensitive photoelectrochemical determination of hydrogen peroxide

Hydrogen peroxide (H2O2) is a major transmitter of redox signals during chemical processes. Cost-effective and easy-to-operate sensors for H2O2 are in high demand in a variety of fields. A novel photoelectrochemical (PEC) sensor for H2O2 detection was investigated, using BiOBr/TiO2NAs/FTO (BiOBr/TNAs) as a PEC electrode which is obtained by successive ionic layer adsorption and reaction (SILAR) method. This non-enzymatic PEC BiOBr/TNAs electrode shows excellent selectivity, stability, and reproducibility for H2O2 detection in optimizing modes. The linear relationship is in a broad range from 4 to 1800 μM (R2 = 0.994) and a detection limit of 0.65 μM (S/N = 3). In the detection of H2O2 in apple juice and milk real samples, the BiOBr/TNAs show outstanding recovery ranging from 98.0 % to 102.0 %, indicating great potential in practical applications. Meanwhile, the p-n heterojunction formed between BiOBr and TiO2 improves the utilization of visible light and effectively promotes the separation of photogenerated electrons and holes. This work provides a new strategy for the non-enzymatic detection of hydrogen peroxide in PEC mode. •3D BiOBr nanoflowers were decorated on TiO2 nanorods arrays (TNAs) synthesized on FTO glass by SILAR methods.•The synergistic interactions between BiOBr and TiO2 offered new opportunities for enzyme-free PEC detection of H2O2.•The BiOBr/TNAs for detecting H2O2 in real apple juice and milk samples showed excellent practical applications.•3D and 1D materials improved the visible light utilization and promoted the separation of electrons and holes.