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Title: 15.3%-Efficient GaAsP Solar Cells on GaP/Si Templates

As single-junction Si solar cells approach their practical efficiency limits, a new pathway is necessary to increase efficiency in order to realize more cost-effective photovoltaics. Integrating III-V cells onto Si in a multijunction architecture is a promising approach that can achieve high efficiency while leveraging the infrastructure already in place for Si and III-V technology. In this Letter, we demonstrate a record 15.3%-efficient 1.7 eV GaAsP top cell on GaP/Si, enabled by recent advances in material quality in conjunction with an improved device design and a high-performance antireflection coating. Furthermore, we present a separate Si bottom cell with a 1.7 eV GaAsP optical filter to absorb most of the visible light with an efficiency of 6.3%, showing the feasibility of monolithic III-V/Si tandems with >20% efficiency. Through spectral efficiency analysis, we also compare our results to previously published GaAsP and Si devices, projecting tandem GaAsP/Si efficiencies of up to 25.6% based on current state-of-the-art individual subcells. With the aid of modeling, we further illustrate a realistic path toward 30% GaAsP/Si tandems for high-efficiency, monolithically integrated photovoltaics.
ORCiD logo [1] ;  [2] ;  [3] ;  [4] ;  [5] ;  [6] ;  [7] ;  [6] ;  [2]
  1. Yale Univ., New Haven, CT (United States). Dept. of Electrical Engineering; National Renewable Energy Lab. (NREL), Golden, CO (United States)
  2. Univ. of Illinois, Urbana-Champaign, IL (United States). Dept. of Electrical and Computer Engineering
  3. Yale Univ., New Haven, CT (United States). Dept. of Electrical Engineering
  4. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  5. King Juan Carlos Univ., Madrid (Spain). Dept. of Electrical Technology
  6. Arizona State Univ., Tempe, AZ (United States). School of Electrical, Computer and Energy Engineering
  7. School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287, United States
Publication Date:
Report Number(s):
Journal ID: ISSN 2380-8195
Grant/Contract Number:
AC36-08GO28308; DMR-1119826
Accepted Manuscript
Journal Name:
ACS Energy Letters
Additional Journal Information:
Journal Volume: 2; Journal Issue: 8; Journal ID: ISSN 2380-8195
American Chemical Society (ACS)
Research Org:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE); National Science Foundation (NSF)
Country of Publication:
United States
14 SOLAR ENERGY; solar cells; efficiency; multijunction
OSTI Identifier: