A scavenger-free and self-powered photoelectrochemical sensor is developed to rapidly detect hydrogen peroxide (H2O2) in the aqueous phase. The resulting CuO/ZnO photocathode composite exhibits two-times higher photocurrent density than the bare CuO under simulated sunlight irradiation, attributed to the formed CuO/ZnO heterojunction with well-aligned band energy levels which promotes the interfacial charge separation of photogenerated electron-hole pairs. Herein, the resulting photocathode composite is assembled as a photoelectrochemical hydrogen peroxide sensor, which shows an instant response within 0.1 s and an approximately 3-fold increase in photocurrent density upon adding 30 mM of H2O2 into the electrolyte. The results further demonstrate that the effect of H2O2 on photocurrent response is concentration-dependent over the wide linear ranges of 0.2–1.0 mM and 1.0–8.0 mM with strong correlations (R2) of 0.992 and 0.986, respectively. The proposed CuO/ZnO photocathode composite can guide the design of efficient hybrid photoelectrodes for solar energy conversion applications.
Bibliographical noteFunding Information:
This project was financially supported by the General Research Fund (GRF 11305419). The authors appreciate the facilities and technical support provided by the UNSW Mark Wainwright Analytical Centre.
This project was financially supported by the General Research Fund (GRF 11305419 ). The authors appreciate the facilities and technical support provided by the UNSW Mark Wainwright Analytical Centre.
- Hydrogen peroxide
- Interfacial charge separation
- Photoelectrochemical sensor
ASJC Scopus subject areas
- General Chemistry
- General Chemical Engineering
- Industrial and Manufacturing Engineering