skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: High-Redox-Potential Chromophores for Visible-Light-Driven Water Oxidation at Low pH

Abstract

Photochemical water oxidation at low pH requires chromophores with adequate photophysical properties and high redox potentials capable of oxidizing the catalysts. We report here a series of homoleptic Ru(II) polypyridyl complexes and their performances in photochemical water oxidation at pH 1 using persulfate as the sacrificial electron acceptor. These chromophores incorporate CF3 or PO3H2 groups to increase the RuIII/II standard potentials to 1.3–1.6 V versus NHE, while their homoleptic nature retains photophysical properties (absorption spectra, lifetimes, emission energies, emission quantum yields) comparable to [Ru(bpy)3]2+. With [(bda)Ru(isq)2] as the catalyst, the chromophores promote visible-light-driven water oxidation with high activity at low pH. The chromophores with phosphonate groups as substituents showed higher activity than expected based on driving force arguments. In addition, kinetic isotope effects as high as ~3 were measured, suggesting the involvement of concerted proton-coupled transfer pathways between the catalyst and the chromophores with the phosphonate group acting as the proton acceptor. These chromophores therefore carry out the light absorption, charge migration, and proton transfer roles of P680, Tyr161, and His190 in Photosystem II on a single molecule and are good candidates for photoelectrochemical water oxidation at low pH in dye-sensitized photoelectrochemical cells.

Authors:
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3];  [3]; ORCiD logo [3]
  1. Stony Brook Univ., NY (United States)
  2. Stony Brook Univ., NY (United States); Brookhaven National Lab. (BNL), Upton, NY (United States)
  3. Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
Research Org.:
Brookhaven National Lab. (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences, and Biosciences Division
OSTI Identifier:
1601341
Report Number(s):
BNL-213649-2020-JAAM
Journal ID: ISSN 2155-5435
Grant/Contract Number:  
SC0012704
Resource Type:
Accepted Manuscript
Journal Name:
ACS Catalysis
Additional Journal Information:
Journal Volume: 10; Journal Issue: 1; Journal ID: ISSN 2155-5435
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; chromophores; high redox potentials; photochemical water oxidation; kinetic isotope effect; PCET; homoleptic; oxidative quenching; quantum yields

Citation Formats

Wang, Lei, Shaffer, David W., Manbeck, Gerald F., Polyansky, Dmitry E., and Concepcion, Javier J.. High-Redox-Potential Chromophores for Visible-Light-Driven Water Oxidation at Low pH. United States: N. p., 2019. Web. https://doi.org/10.1021/acscatal.9b04034.
Wang, Lei, Shaffer, David W., Manbeck, Gerald F., Polyansky, Dmitry E., & Concepcion, Javier J.. High-Redox-Potential Chromophores for Visible-Light-Driven Water Oxidation at Low pH. United States. https://doi.org/10.1021/acscatal.9b04034
Wang, Lei, Shaffer, David W., Manbeck, Gerald F., Polyansky, Dmitry E., and Concepcion, Javier J.. Wed . "High-Redox-Potential Chromophores for Visible-Light-Driven Water Oxidation at Low pH". United States. https://doi.org/10.1021/acscatal.9b04034. https://www.osti.gov/servlets/purl/1601341.
@article{osti_1601341,
title = {High-Redox-Potential Chromophores for Visible-Light-Driven Water Oxidation at Low pH},
author = {Wang, Lei and Shaffer, David W. and Manbeck, Gerald F. and Polyansky, Dmitry E. and Concepcion, Javier J.},
abstractNote = {Photochemical water oxidation at low pH requires chromophores with adequate photophysical properties and high redox potentials capable of oxidizing the catalysts. We report here a series of homoleptic Ru(II) polypyridyl complexes and their performances in photochemical water oxidation at pH 1 using persulfate as the sacrificial electron acceptor. These chromophores incorporate CF3 or PO3H2 groups to increase the RuIII/II standard potentials to 1.3–1.6 V versus NHE, while their homoleptic nature retains photophysical properties (absorption spectra, lifetimes, emission energies, emission quantum yields) comparable to [Ru(bpy)3]2+. With [(bda)Ru(isq)2] as the catalyst, the chromophores promote visible-light-driven water oxidation with high activity at low pH. The chromophores with phosphonate groups as substituents showed higher activity than expected based on driving force arguments. In addition, kinetic isotope effects as high as ~3 were measured, suggesting the involvement of concerted proton-coupled transfer pathways between the catalyst and the chromophores with the phosphonate group acting as the proton acceptor. These chromophores therefore carry out the light absorption, charge migration, and proton transfer roles of P680, Tyr161, and His190 in Photosystem II on a single molecule and are good candidates for photoelectrochemical water oxidation at low pH in dye-sensitized photoelectrochemical cells.},
doi = {10.1021/acscatal.9b04034},
journal = {ACS Catalysis},
number = 1,
volume = 10,
place = {United States},
year = {2019},
month = {11}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 1 work
Citation information provided by
Web of Science

Save / Share: