Light-Driven Water Splitting Mediated by Photogenerated Bromine
- Florida International Univ., Miami, FL (United States)
- Univ. of North Carolina, Chapel Hill, NC (United States)
- Texas Christian Univ. (TCU), Fort Worth, TX (United States)
Abstract Light‐driven water splitting was achieved using a dye‐sensitized mesoporous oxide film and the oxidation of bromide (Br − ) to bromine (Br 2 ) or tribromide (Br 3 − ). The chemical oxidant (Br 2 or Br 3 − ) is formed during illumination at the photoanode and used as a sacrificial oxidant to drive a water oxidation catalyst (WOC), here demonstrated using [Ru(bda)(pic) 2 ], ( 1 ; pic=picoline, bda=2,2′‐bipyridine‐6,6′‐dicarboxylate). The photochemical oxidation of bromide produces a chemical oxidant with a potential of 1.09 V vs. NHE for the Br 2 /Br − couple or 1.05 V vs. NHE for the Br 3 − /Br − couple, which is sufficient to drive water oxidation at 1 (Ru V/IV ≈1.0 V vs. NHE at pH 5.6). At pH 5.6, using a 0.2 m acetate buffer containing 40 m m LiBr and the [Ru(4,4′‐PO 3 H 2 ‐bpy)(bpy) 2 ] 2+ ( RuP 2+ , bpy=2,2′‐bipyridine) chromophore dye on a SnO 2 /TiO 2 core–shell electrode resulted in a photocurrent density of around 1.2 mA cm −2 under approximately 1 Sun illumination and a Faradaic efficiency upon addition of 1 of 77 % for oxygen evolution.
- Research Organization:
- Univ. of North Carolina, Chapel Hill, NC (United States). Energy Frontier Research Center (EFRC) Center for Solar Fuels (UNC)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)
- Grant/Contract Number:
- SC0001011
- OSTI ID:
- 1470106
- Alternate ID(s):
- OSTI ID: 1423382
- Journal Information:
- Angewandte Chemie (International Edition), Vol. 57, Issue 13; Related Information: UNC partners with University of North Carolina (lead); Duke University; University of Florida; Georgia Institute of Technology; University; North Carolina Central University; Research Triangle Institute; ISSN 1433-7851
- Publisher:
- WileyCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
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