Structure and Valency of a Cobalt−Phosphate Water Oxidation Catalyst Determined by in Situ X-ray Spectroscopy
Massachusetts Institute of Technology · Lawrence Berkeley National Laboratory
Abstract
A water oxidation catalyst generated via electrodeposition from aqueous solutions containing phosphate and Co(2+) (Co-Pi) has been studied by in situ X-ray absorption spectroscopy. Spectra were obtained for Co-Pi films of two different thicknesses at an applied potential supporting water oxidation catalysis and at open circuit. Extended X-ray absorption fine structure (EXAFS) spectra indicate the presence of bis-oxo/hydroxo-bridged Co subunits incorporated into higher nuclearity clusters in Co-Pi. The average cluster nuclearity is greater in a relatively thick film (∼40-50 nmol Co ions/cm(2)) deposited at 1.25 V vs NHE than in an extremely thin film (∼3 nmol Co ions/cm(2)) deposited at 1.1 V. X-ray absorption…
Citation impact
- FWCI
- 21.39
- Percentile
- 100%
- References
- 47
Authors
6- MWMatthew W. KananCorresponding
Massachusetts Institute of Technology, Lawrence Berkeley National Laboratory
- JYJunko Yano
Massachusetts Institute of Technology, Lawrence Berkeley National Laboratory
- YSYogesh Surendranath
Massachusetts Institute of Technology, Lawrence Berkeley National Laboratory
- MDMircea Dincă
Lawrence Berkeley National Laboratory, Massachusetts Institute of Technology
- VKVittal K. Yachandra
Massachusetts Institute of Technology, Lawrence Berkeley National Laboratory
Topics & keywords
- Extended X-ray absorption fine structure
- Chemistry
- XANES
- Valency
- Catalysis
- Absorption spectroscopy
- Crystallography
- X-ray absorption spectroscopy
- Clean water and sanitation