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Title: High-quality LaVO 3 films as solar energy conversion material

Abstract

Mott insulating oxides and their heterostructures have recently been identified as potential photovoltaic materials with favorable absorption properties and an intrinsic built-in electric field that can efficiently separate excited electron hole pairs. At the same time, they are predicted to overcome the Shockley-Queisser limit due to strong electron electron interaction present. Despite these premises a high concentration of defects commonly observed in Mott insulating films acting as recombination centers can derogate the photovoltaic conversion efficiency. With use of the self-regulated growth kinetics in hybrid molecular beam epitaxy, this obstacle can be overcome. High-quality, stoichiometric LaVO 3 films were grown with defect densities of in-gap states up to 2 orders of magnitude lower compared to the films in the literature, and a factor of 3 lower than LaVO 3 bulk single crystals. Photoconductivity measurements revealed a significant photoresponsivity increase as high as tenfold of stoichiometric LaVO 3 films compared to their nonstoichiometric counterparts. Furthermore, this work marks a critical step toward the realization of high-performance Mott insulator solar cells beyond conventional semiconductors.

Authors:
ORCiD logo [1];  [1]; ORCiD logo [1];  [1];  [1];  [2];  [1];  [1]
  1. Pennsylvania State Univ., University Park, PA (United States)
  2. Argonne National Lab. (ANL), Lemont, IL (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22), Scientific User Facilities Division
OSTI Identifier:
1371945
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
ACS Applied Materials and Interfaces
Additional Journal Information:
Journal Volume: 9; Journal Issue: 14; Journal ID: ISSN 1944-8244
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; thin film; Mott insulator; photovoltaic materials; physical vapor deposition; transitional metal oxide

Citation Formats

Zhang, Hai -Tian, Brahlek, Matthew, Ji, Xiaoyu, Lei, Shiming, Lapano, Jason, Freeland, John W., Gopalan, Venkatraman, and Engel-Herbert, Roman. High-quality LaVO3 films as solar energy conversion material. United States: N. p., 2017. Web. doi:10.1021/acsami.6b16007.
Zhang, Hai -Tian, Brahlek, Matthew, Ji, Xiaoyu, Lei, Shiming, Lapano, Jason, Freeland, John W., Gopalan, Venkatraman, & Engel-Herbert, Roman. High-quality LaVO3 films as solar energy conversion material. United States. doi:10.1021/acsami.6b16007.
Zhang, Hai -Tian, Brahlek, Matthew, Ji, Xiaoyu, Lei, Shiming, Lapano, Jason, Freeland, John W., Gopalan, Venkatraman, and Engel-Herbert, Roman. Tue . "High-quality LaVO3 films as solar energy conversion material". United States. doi:10.1021/acsami.6b16007. https://www.osti.gov/servlets/purl/1371945.
@article{osti_1371945,
title = {High-quality LaVO3 films as solar energy conversion material},
author = {Zhang, Hai -Tian and Brahlek, Matthew and Ji, Xiaoyu and Lei, Shiming and Lapano, Jason and Freeland, John W. and Gopalan, Venkatraman and Engel-Herbert, Roman},
abstractNote = {Mott insulating oxides and their heterostructures have recently been identified as potential photovoltaic materials with favorable absorption properties and an intrinsic built-in electric field that can efficiently separate excited electron hole pairs. At the same time, they are predicted to overcome the Shockley-Queisser limit due to strong electron electron interaction present. Despite these premises a high concentration of defects commonly observed in Mott insulating films acting as recombination centers can derogate the photovoltaic conversion efficiency. With use of the self-regulated growth kinetics in hybrid molecular beam epitaxy, this obstacle can be overcome. High-quality, stoichiometric LaVO3 films were grown with defect densities of in-gap states up to 2 orders of magnitude lower compared to the films in the literature, and a factor of 3 lower than LaVO3 bulk single crystals. Photoconductivity measurements revealed a significant photoresponsivity increase as high as tenfold of stoichiometric LaVO3 films compared to their nonstoichiometric counterparts. Furthermore, this work marks a critical step toward the realization of high-performance Mott insulator solar cells beyond conventional semiconductors.},
doi = {10.1021/acsami.6b16007},
journal = {ACS Applied Materials and Interfaces},
number = 14,
volume = 9,
place = {United States},
year = {Tue Mar 21 00:00:00 EDT 2017},
month = {Tue Mar 21 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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Cited by: 2works
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