Solar hydrogen peroxide production on carbon nanotubes wired to titania nanorod arrays catalyzing As(III) oxidation

Seung Yo Choi, Seonghun Kim, Kyung Jin Lee, Jin Young Kim, Dong Suk Han, Hyunwoong Park

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

We present an off-grid, standalone electrocatalytic H 2 O 2 production reaction (HPR) using carbon nanotubes (CNT) wired to hydrogen-treated TiO 2 nanorod (h-TNR) arrays catalyzing the oxidation of As(III) to As(V) under simulated solar light (AM 1.5; 100 mW cm −2 ). Loading CNT onto acid-treated carbon paper (a-CP) significantly enhances the catalytic 2-electron transfer to O 2 , leading to a Faradaic efficiency (FE) of ∼100% for the HPR. To drive the HPR, the 2-electron oxidation of toxic As(III) to less toxic As(V) that accompanies the production of the proton/electron couples is achieved at an FE of >80% using the h-TNR arrays. The high FEs of the anodic and cathodic reactions are maintained over 10 h when a direct-current voltage of 0.7 V is applied to the h-TNR photoanode and CNT/a-CP cathode pair. The coupling of a mono-Si photovoltaic array that is one-tenth the size of h-TNR photoanode to the pair of h-TNR and CNT/a-CP successfully drives the standalone operation of both reactions at the high FEs (>90%). The surface characterization of the as-synthesized materials and the reaction mechanism are discussed in detail.

Original languageEnglish
Pages (from-to)55-61
Number of pages7
JournalApplied Catalysis B: Environmental
Volume252
DOIs
Publication statusPublished - 5 Sep 2019

    Fingerprint

Keywords

  • Arsenic oxidation
  • Artificial photosynthesis
  • Carbon electrode
  • Oxygen reduction reaction
  • TiO nanorod arrays

ASJC Scopus subject areas

  • Catalysis
  • Environmental Science(all)
  • Process Chemistry and Technology

Cite this