Cobalt-to-vanadium charge transfer in polyoxometalate water oxidation catalysts revealed by 2p3d resonant inelastic X-ray scattering. Issue 6 (29th January 2018)

• Record Type: Journal Article
• Authors: Liu, Boyang; Glass, Elliot N.; Wang, Ru-Pan; Cui, Yi-Tao; Harada, Yoshihisa; Huang, Di-Jing; Schuppler, Stefan; Hill, Craig L.; de Groot, Frank M. F.
• Is Part Of: Physical chemistry chemical physics. Volume 20:Issue 6(2018)
• Page Start: 4554
• Page End: 4562
• Publication Date: 2018-01-29
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c7cp06786k
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : 2p3d RIXS spectra reveal electronic structures ofCo4 V2 WOC, which offers insights into its enhanced catalytic activity thanCo4 P2 WOC. Abstract : Two isostructural cobalt containing polyoxometalate water oxidation catalysts, [Co4 (H2 O)2 (α-PW9 O34 )2 ] 10− (Co4 P2 ) and [Co4 (H2 O)2 (α-VW9 O34 )2 ] 10− (Co4 V2 ), exhibit large differences in their catalytic performance. The substitution of phosphorus centers inCo4 P2 with redox-active vanadium centers inCo4 V2 leads to electronic structure modifications. Evidence for the significance of the vanadium centers to catalysis, predicted by theory, was found from soft X-ray absorption (XAS) and resonant inelastic X-ray scattering (RIXS). The XAS and RIXS spectra determine the electronic structure of the cobalt and vanadium sites in the pre-reaction state of bothCo4 V2 andCo4 P2 . High-energy resolution RIXS results reveal thatCo4 V2 possesses a smaller ligand field within the tetra-cobalt core and a cobalt-to-vanadium charge transfer band. The differences in electronic structures offer insights into the enhanced catalysis ofCo4 V2 .