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Title: Enhanced visible light photocatalytic water reduction from a g-C 3N 4/SrTa 2O 6 heterojunction

Abstract

In this paper, a new g-C 3N 4/SrTa 2O 6 heterojunction photocatalyst was designed and prepared by chimie douce (soft chemistry) method where carbon nitride (g-C 3N 4) was deposited over the metastable perovskite phase of SrTa 2O 6. The morphological study of the heterojunction using SEM and STEM revealed that g-C 3N 4 nanofibers are dispersed uniformly on the surface of SrTa 2O 6 plates leading to the intimate contact between them. The heterojunction could achieve a high and stable visible light photocatalytic H 2 generation of 137 mmol/h/mole of g-C 3N 4, which is much larger than the amount of hydrogen generated by one mole of pristine g-C 3N 4. Finally, a plausible mechanism for the observed enhanced photocatalytic activity for the heterojunction is proposed on the basis of effective charge separation of photogenerated electron-hole pairs, supported by band position calculations and photo-physical properties of g-C 3N 4 and SrTa 2O 6.

Authors:
 [1];  [2];  [3];  [4];  [5];  [5];  [6];  [4];  [4];  [5];  [1]
  1. Wake Forest Univ., Winston-Salem, NC (United States). Dept. of Chemistry. Center for Energy, Environment and Sustainability (CEES)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences; Georgia Inst. of Technology, Atlanta, GA (United States). School of Chemistry and Biochemistry
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences; Univ. of Louisville, KY (United States). Dept. of Mechanical Engineering. Conn Center for Renewable Energy Research
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences
  5. Wake Forest Univ., Winston-Salem, NC (United States). Dept. of Chemistry
  6. Georgia Inst. of Technology, Atlanta, GA (United States). School of Chemistry and Biochemistry
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC); National Science Foundation (NSF); Wake Forest Univ. (United States)
Contributing Org.:
Univ. of Louisville, KY (United States)
OSTI Identifier:
1376489
Grant/Contract Number:
AC05-00OR22725; MRI1040264; DGE-1148903
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Applied Catalysis. B, Environmental
Additional Journal Information:
Journal Volume: 217; Journal ID: ISSN 0926-3373
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Photocatalysis; Semiconductor; Heterojunction; Perovskite; Hydrogen

Citation Formats

Adhikari, Shiba P., Hood, Zachary D., Wang, Hui, Peng, Rui, Krall, Alex, Li, Hui, Chen, Vincent W., More, Karren L., Wu, Zili, Geyer, Scott, and Lachgar, Abdou. Enhanced visible light photocatalytic water reduction from a g-C3N4/SrTa2O6 heterojunction. United States: N. p., 2017. Web. doi:10.1016/j.apcatb.2017.05.092.
Adhikari, Shiba P., Hood, Zachary D., Wang, Hui, Peng, Rui, Krall, Alex, Li, Hui, Chen, Vincent W., More, Karren L., Wu, Zili, Geyer, Scott, & Lachgar, Abdou. Enhanced visible light photocatalytic water reduction from a g-C3N4/SrTa2O6 heterojunction. United States. doi:10.1016/j.apcatb.2017.05.092.
Adhikari, Shiba P., Hood, Zachary D., Wang, Hui, Peng, Rui, Krall, Alex, Li, Hui, Chen, Vincent W., More, Karren L., Wu, Zili, Geyer, Scott, and Lachgar, Abdou. Fri . "Enhanced visible light photocatalytic water reduction from a g-C3N4/SrTa2O6 heterojunction". United States. doi:10.1016/j.apcatb.2017.05.092.
@article{osti_1376489,
title = {Enhanced visible light photocatalytic water reduction from a g-C3N4/SrTa2O6 heterojunction},
author = {Adhikari, Shiba P. and Hood, Zachary D. and Wang, Hui and Peng, Rui and Krall, Alex and Li, Hui and Chen, Vincent W. and More, Karren L. and Wu, Zili and Geyer, Scott and Lachgar, Abdou},
abstractNote = {In this paper, a new g-C3N4/SrTa2O6 heterojunction photocatalyst was designed and prepared by chimie douce (soft chemistry) method where carbon nitride (g-C3N4) was deposited over the metastable perovskite phase of SrTa2O6. The morphological study of the heterojunction using SEM and STEM revealed that g-C3N4 nanofibers are dispersed uniformly on the surface of SrTa2O6 plates leading to the intimate contact between them. The heterojunction could achieve a high and stable visible light photocatalytic H2 generation of 137 mmol/h/mole of g-C3N4, which is much larger than the amount of hydrogen generated by one mole of pristine g-C3N4. Finally, a plausible mechanism for the observed enhanced photocatalytic activity for the heterojunction is proposed on the basis of effective charge separation of photogenerated electron-hole pairs, supported by band position calculations and photo-physical properties of g-C3N4 and SrTa2O6.},
doi = {10.1016/j.apcatb.2017.05.092},
journal = {Applied Catalysis. B, Environmental},
number = ,
volume = 217,
place = {United States},
year = {Fri Jun 02 00:00:00 EDT 2017},
month = {Fri Jun 02 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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