Efficient charge generation from triplet excitons in metal-organic heterojunctions
(2019) In Physical Review B 99(2).- Abstract
The success of many emerging molecular electronics concepts hinges on an atomistic understanding of the underlying electronic dynamics. We employ picosecond time-resolved x-ray photoemission spectroscopy (tr-XPS) to elucidate the roles of singlet and triplet excitons for photoinduced charge generation at a copper-phthalocyanine-C60 heterojunction. Contrary to common belief, fast intersystem crossing to triplet excitons after photoexcitation is not a loss channel but contributes to a significantly larger extent to the time-integrated interfacial charge generation than the initially excited singlet excitons. The tr-XPS data provide direct access to the diffusivity of the triplet excitons DCuPc=(1.8±1.2)×10-5cm2/s (where CuPc is... (More)
The success of many emerging molecular electronics concepts hinges on an atomistic understanding of the underlying electronic dynamics. We employ picosecond time-resolved x-ray photoemission spectroscopy (tr-XPS) to elucidate the roles of singlet and triplet excitons for photoinduced charge generation at a copper-phthalocyanine-C60 heterojunction. Contrary to common belief, fast intersystem crossing to triplet excitons after photoexcitation is not a loss channel but contributes to a significantly larger extent to the time-integrated interfacial charge generation than the initially excited singlet excitons. The tr-XPS data provide direct access to the diffusivity of the triplet excitons DCuPc=(1.8±1.2)×10-5cm2/s (where CuPc is copper-phthalocyanine) and their diffusion length Ldiff=(8±3)nm.
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- author
- Roth, Friedrich ; Neppl, Stefan ; Shavorskiy, Andrey LU ; Arion, Tiberiu ; Mahl, Johannes ; Seo, Hyun Ook ; Bluhm, Hendrik ; Hussain, Zahid ; Gessner, Oliver and Eberhardt, Wolfgang
- organization
- publishing date
- 2019-01
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Physical Review B
- volume
- 99
- issue
- 2
- article number
- 020303
- publisher
- American Physical Society
- external identifiers
-
- scopus:85059898315
- ISSN
- 2469-9950
- DOI
- 10.1103/PhysRevB.99.020303
- language
- English
- LU publication?
- yes
- id
- 016e1b75-5ce0-4bc8-9448-c64883e51add
- date added to LUP
- 2022-04-04 09:55:05
- date last changed
- 2023-11-24 06:44:25
@article{016e1b75-5ce0-4bc8-9448-c64883e51add, abstract = {{<p>The success of many emerging molecular electronics concepts hinges on an atomistic understanding of the underlying electronic dynamics. We employ picosecond time-resolved x-ray photoemission spectroscopy (tr-XPS) to elucidate the roles of singlet and triplet excitons for photoinduced charge generation at a copper-phthalocyanine-C60 heterojunction. Contrary to common belief, fast intersystem crossing to triplet excitons after photoexcitation is not a loss channel but contributes to a significantly larger extent to the time-integrated interfacial charge generation than the initially excited singlet excitons. The tr-XPS data provide direct access to the diffusivity of the triplet excitons DCuPc=(1.8±1.2)×10-5cm2/s (where CuPc is copper-phthalocyanine) and their diffusion length Ldiff=(8±3)nm.</p>}}, author = {{Roth, Friedrich and Neppl, Stefan and Shavorskiy, Andrey and Arion, Tiberiu and Mahl, Johannes and Seo, Hyun Ook and Bluhm, Hendrik and Hussain, Zahid and Gessner, Oliver and Eberhardt, Wolfgang}}, issn = {{2469-9950}}, language = {{eng}}, number = {{2}}, publisher = {{American Physical Society}}, series = {{Physical Review B}}, title = {{Efficient charge generation from triplet excitons in metal-organic heterojunctions}}, url = {{http://dx.doi.org/10.1103/PhysRevB.99.020303}}, doi = {{10.1103/PhysRevB.99.020303}}, volume = {{99}}, year = {{2019}}, }