skip to main content

DOE PAGESDOE PAGES

This content will become publicly available on June 8, 2019

Title: Anatomy of a Visible Light Activated Photocatalyst for Water Splitting

The supported mixed oxide (Rh 2-yCr yO 3)/(Ga 1-xZn x)(N 1-xO x) photocatalyst, highly active for splitting of H 2O, was extensively characterized for its bulk and surface properties with the objective of developing fundamental structure-photoactivity relationships. Raman and UV-vis spectroscopy revealed that the molecular and electronic structures, respectively, of the oxynitride (Ga 1-xZn x)(N 1-xO x) support are not perturbed by the deposition of the (Rh 2-yCr yO 3) NPs. Photoluminescence (PL) spectroscopy, however, showed that the oxynitride (Ga 1-xZn x)(N 1-xO x) support is the source of excited electrons/holes and the (Rh 2-yCr yO 3) NPs greatly reduce the undesirable recombination of photoexcited electron/holes by acting as efficient electron traps as well as increase the lifetimes of the excitons. High Resolution-XPS and High Sensitivity-LEIS surface analyses reveal that the surfaces of the (Rh 2-yCr yO 3) NPs consist of Rh +3 and Cr +3 mixed oxide species. In Situ AP-XPS help to reveal that the Rh+3 and surface N atoms are involved in water splitting. Dispersed RhOx species on the (Ga 1-xZn x)(N 1-xO x) support and on CrO x NPs were found to be the photocatalytic active sites for H 2 generation and N and Zn sitesmore » from the (Ga 1-xZn x)(N 1-xO x) support are the photocatalytic active site for O 2 generation. In conclusion, the current investigation establishes the fundamental structure-photoactivity relationships of these visible light activated photocatalysts.« less
Authors:
 [1] ;  [1] ;  [2] ;  [2] ;  [3] ;  [3] ;  [3] ;  [4] ;  [5] ;  [6] ;  [4] ;  [1]
  1. Lehigh Univ., Bethlehem, PA (United States)
  2. Brookhaven National Lab. (BNL), Upton, NY (United States)
  3. Univ. of Kansas, Lawrence, KS (United States)
  4. Univ. of Tokyo (Japan)
  5. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC)
  6. (Feng) [Univ. of Kansas, Lawrence, KS (United States)
Publication Date:
Grant/Contract Number:
FG02-93ER14350; AC05-00OR22725
Type:
Accepted Manuscript
Journal Name:
ACS Catalysis
Additional Journal Information:
Journal Volume: 8; Journal Issue: 7; Journal ID: ISSN 2155-5435
Publisher:
American Chemical Society (ACS)
Research Org:
Lehigh Univ., Bethlehem, PA (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; AP-XPS; HS-LEIS; photocatalysis; photocatalyst; spectroscopy; water splitting
OSTI Identifier:
1440775
Alternate Identifier(s):
OSTI ID: 1461067