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Title: Solar upconversion with plasmon-enhanced bimolecular complexes

Abstract

Upconversion of sub-bandgap photons is a promising approach to exceed the Shockley-Queisser limit in solar technologies. However, due to the low quantum efficiencies and narrow absorption bandwidths of upconverters, existing systems have only led to fractional percent improvements in photovoltaic devices (~0.01%). In this project, we aimed to develop an efficient upconverting material that could improve cell efficiencies by at least one absolute percent. To achieve this goal, we first used thermodynamic calculations to determine cell efficiencies with realistic upconverting materials. Then, we designed, synthesized, and characterized nanoantennas that promise >100x enhancement in both the upconverter absorption cross-section and emissive radiative rate. Concurrently, we optimized the upconverer by designing new ionic and molecular complexes that promise efficient solid-state upconversion. Lastly, with Bosch, we simulated record-efficiency semi-transparent cells that will allow for ready incorporation of our upconverting materials. While we were not successful in designing record efficiency upconverters during our three years of funding, we gained significant insight into the existing limitations of upconverters and how to best address these challenges. Ongoing work is aimed at addressing these limitations, to make upconversion a cost-competitive solar technology in future years.

Authors:
 [1]
  1. Stanford Univ., CA (United States)
Publication Date:
Research Org.:
Stanford Univ., CA (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S)
OSTI Identifier:
1351405
Report Number(s):
1
DOE Contract Number:
EE0005331
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

Dionne, Jennifer. Solar upconversion with plasmon-enhanced bimolecular complexes. United States: N. p., 2017. Web. doi:10.2172/1351405.
Dionne, Jennifer. Solar upconversion with plasmon-enhanced bimolecular complexes. United States. doi:10.2172/1351405.
Dionne, Jennifer. Fri . "Solar upconversion with plasmon-enhanced bimolecular complexes". United States. doi:10.2172/1351405. https://www.osti.gov/servlets/purl/1351405.
@article{osti_1351405,
title = {Solar upconversion with plasmon-enhanced bimolecular complexes},
author = {Dionne, Jennifer},
abstractNote = {Upconversion of sub-bandgap photons is a promising approach to exceed the Shockley-Queisser limit in solar technologies. However, due to the low quantum efficiencies and narrow absorption bandwidths of upconverters, existing systems have only led to fractional percent improvements in photovoltaic devices (~0.01%). In this project, we aimed to develop an efficient upconverting material that could improve cell efficiencies by at least one absolute percent. To achieve this goal, we first used thermodynamic calculations to determine cell efficiencies with realistic upconverting materials. Then, we designed, synthesized, and characterized nanoantennas that promise >100x enhancement in both the upconverter absorption cross-section and emissive radiative rate. Concurrently, we optimized the upconverer by designing new ionic and molecular complexes that promise efficient solid-state upconversion. Lastly, with Bosch, we simulated record-efficiency semi-transparent cells that will allow for ready incorporation of our upconverting materials. While we were not successful in designing record efficiency upconverters during our three years of funding, we gained significant insight into the existing limitations of upconverters and how to best address these challenges. Ongoing work is aimed at addressing these limitations, to make upconversion a cost-competitive solar technology in future years.},
doi = {10.2172/1351405},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Apr 14 00:00:00 EDT 2017},
month = {Fri Apr 14 00:00:00 EDT 2017}
}

Technical Report:

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  • The electronic properties of Nb(100) are studied using angle-resolved photoemission. Several surface resonances are identified. One surface resonance exhibits significant enhancement of the photoemission cross section at the bulk plasma energy, suggesting a novel probe of surface resonances having high degree of second-layer charge density. The authors report the observation of bulk-plasmon-enhanced photoemission from Nb(100) surface resonances. This effect offers a sensitive direct probe of the spatial extent of surface states and surface resonances at metal surfaces in cases where a high degree of second-layer charge density exists in the two-dimensional Brillouin zone. A related enhancement effect was recently reportedmore » by Drube and Himpsel for inverse photoemission. Photoemission cross section resonances associated with surface states that arise from final state effects were also observed on silver and copper surfaces. However, these resonances are produced by a distinctly different mechanism than the one described in this paper.« less
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