Scavenger-free and self-powered photocathodic sensing system for aqueous hydrogen peroxide monitoring by CuO/ZnO nanostructure

Hao Wu, Hoi Ying Chung, Daniel C.W. Tsang, Nay Ming Huang, Zhirun Xie, Hong Ngee Lim, Yong Sik Ok, Yun Hau Ng

Research output: Journal article publicationJournal articleAcademic researchpeer-review

1 Citation (Scopus)

Abstract

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.

Original languageEnglish
Article number115886
JournalChemical Engineering Science
Volume226
DOIs
Publication statusPublished - 23 Nov 2020

Keywords

  • CuO/ZnO
  • Hydrogen peroxide
  • Interfacial charge separation
  • Photoelectrochemical sensor

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)
  • Industrial and Manufacturing Engineering

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