Narrow band gap lead sulfide hole transport layers for quantum dot photovoltaics
The band structure of colloidal quantum dot (CQD) bilayer heterojunction solar cells is optimized using a combination of ligand modification and QD band gap control. Solar cells with power conversion efficiencies of up to 9.33 ± 0.50% are demonstrated by aligning the absorber and hole transport laye...
| Main Authors: | , , , , , , |
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| Format: | Journal article |
| Language: | English |
| Published: |
American Chemical Society
2016
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| _version_ | 1826264386469101568 |
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| author | Zhang, N Neo, D Tazawa, Y Li, X Assender, H Compton, R Watt, A |
| author_facet | Zhang, N Neo, D Tazawa, Y Li, X Assender, H Compton, R Watt, A |
| author_sort | Zhang, N |
| collection | OXFORD |
| description | The band structure of colloidal quantum dot (CQD) bilayer heterojunction solar cells is optimized using a combination of ligand modification and QD band gap control. Solar cells with power conversion efficiencies of up to 9.33 ± 0.50% are demonstrated by aligning the absorber and hole transport layers (HTL). Key to achieving high efficiencies is optimizing the relative position of both the valence band and Fermi energy at the CQD bilayer interface. By comparing different band-gap CQDs with different ligands we find that a smaller band gap CQD HTL in combination with a more p-type-inducing CQD ligand is found to enhance hole extraction and hence device performance. We postulate that the efficiency improvements observed are largely due to the synergistic effects of narrower band-gap QDs causing an upshift of valence band position due to 1, 2-ethanedithiol (EDT) ligands and a lowering of the Fermi level due to oxidation. |
| first_indexed | 2024-03-06T20:06:58Z |
| format | Journal article |
| id | oxford-uuid:2933db86-c696-4216-bc6b-c3ce43924550 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T20:06:58Z |
| publishDate | 2016 |
| publisher | American Chemical Society |
| record_format | dspace |
| spelling | oxford-uuid:2933db86-c696-4216-bc6b-c3ce439245502022-03-26T12:17:49ZNarrow band gap lead sulfide hole transport layers for quantum dot photovoltaicsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:2933db86-c696-4216-bc6b-c3ce43924550EnglishSymplectic Elements at OxfordAmerican Chemical Society2016Zhang, NNeo, DTazawa, YLi, XAssender, HCompton, RWatt, AThe band structure of colloidal quantum dot (CQD) bilayer heterojunction solar cells is optimized using a combination of ligand modification and QD band gap control. Solar cells with power conversion efficiencies of up to 9.33 ± 0.50% are demonstrated by aligning the absorber and hole transport layers (HTL). Key to achieving high efficiencies is optimizing the relative position of both the valence band and Fermi energy at the CQD bilayer interface. By comparing different band-gap CQDs with different ligands we find that a smaller band gap CQD HTL in combination with a more p-type-inducing CQD ligand is found to enhance hole extraction and hence device performance. We postulate that the efficiency improvements observed are largely due to the synergistic effects of narrower band-gap QDs causing an upshift of valence band position due to 1, 2-ethanedithiol (EDT) ligands and a lowering of the Fermi level due to oxidation. |
| spellingShingle | Zhang, N Neo, D Tazawa, Y Li, X Assender, H Compton, R Watt, A Narrow band gap lead sulfide hole transport layers for quantum dot photovoltaics |
| title | Narrow band gap lead sulfide hole transport layers for quantum dot photovoltaics |
| title_full | Narrow band gap lead sulfide hole transport layers for quantum dot photovoltaics |
| title_fullStr | Narrow band gap lead sulfide hole transport layers for quantum dot photovoltaics |
| title_full_unstemmed | Narrow band gap lead sulfide hole transport layers for quantum dot photovoltaics |
| title_short | Narrow band gap lead sulfide hole transport layers for quantum dot photovoltaics |
| title_sort | narrow band gap lead sulfide hole transport layers for quantum dot photovoltaics |
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