uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Second Generation of DiketopyrrolopyrroleDyes for NiO based Dye-Sensitized Solar Cells
Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry. (Prof Hammarstrom Leif's group)
Show others and affiliations
2016 (English)In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 120, no 15, 7923-7940 p.Article in journal (Refereed) Published
Abstract [en]

In this study, four new diketopyrrolopyrrole (DPP) sensitizers, with a dicarboxylated triphenylamine anchoring group for attachment to NiO, were prepared and their electronic absorption, emission and electrochemical properties were recorded. The nature of the electronic excited-states was also modeled with TD-DFT quantum chemistry calculations. The photovoltaic performances of these new dyes were characterized in NiO-based dye-sensitized solar cells (DSCs) with the classical iodide/triiodide and cobaltII/III-polypyridine electrolytes, in which they proved to be quite active. Laser spectroscopy on dye/NiO/electrolyte films gave evidence for ultrafast hole injection into NiO (0.2-10 ps time scales). For the dyes with an appended naphtalenediimide (NDI) acceptor unit, ultrafast electron transfer to the NDI dramatically prolonged the lifetime of the charge separated state NiO(+)/dye-, from the ps time scale to an average lifetime ≈ 0.25 ms, which is among the slowest charge recombinations ever reported for dye/NiO systems. This allowed for efficient regeneration by CoIIIpolypyridine electrolytes, which translated into much improved PV-performance compared to the DPP dyes without appended NDI. Overall, these results underscore the suitability of DPP as sensitizers for NiO-based photoelectrochemical devices for photovoltaic and photocatalysis.

Place, publisher, year, edition, pages
2016. Vol. 120, no 15, 7923-7940 p.
National Category
Physical Chemistry
Identifiers
URN: urn:nbn:se:uu:diva-280841DOI: 10.1021/acs.jpcc.5b12489ISI: 000374811100004OAI: oai:DiVA.org:uu-280841DiVA: diva2:912160
Funder
EU, European Research Council, Marches -278845Knut and Alice Wallenberg FoundationSwedish Energy AgencySwedish Research Council
Available from: 2016-03-15 Created: 2016-03-15 Last updated: 2017-11-30Bibliographically approved
In thesis
1. Exploring Electron Transfer Dynamics of Novel Dye Sensitized Photocathodes: Towards Solar Cells and Solar Fuels
Open this publication in new window or tab >>Exploring Electron Transfer Dynamics of Novel Dye Sensitized Photocathodes: Towards Solar Cells and Solar Fuels
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The design of dyes for NiO-based dye-sensitized solar cells (DSSCs) has drawn attention owing to their potential applications in photocatalysis and because they are indispensable for the development of tandem dye-sensitized solar cells. The understanding of the electron transfer mechanisms and dynamics is beneficial to guide further dye design and further improve the performance of photocathode in solar cells and solar fuel devices.

Time-resolved spectroscopy techniques, especially femtosecond and nanosecond transient absorption spectroscopy, supply sufficient resolution to get insights into the charge transfer processes in p-type dye sensitized solar cell and solar fuel devices. In paper I-V, several kinds of novel organic “push-pull” and inorganic charge transfer dyes for sensitization of p-type NiO, were systematically investigated by time-resolved spectroscopy, and photo-induced charge transfer dynamics of the organic/inorganic dyes were summarized. The excited state and reduced state intermediates were investigated in solution phase as references to confirm the charge injection and recombination on the NiO surface. The charge recombination kinetics is remarkably heterogeneous in some cases occurring on time scales spanning at least six orders of magnitude even for the same dye.

In this thesis, we also proposed a novel concept of solid state p-type dye sensitized solar cells (p-ssDSSCs) for the first time (paper VI), using an organic dye P1 as sensitizer on mesoporous NiO and phenyl-C61-butyric acid methyl ester (PCBM) as electron conductor. Femtosecond and nanosecond transient absorption spectroscopy gave evidence for sub-ps hole injection from excited P1 to NiO, followed by electron transfer from P1●- to PCBM. The p-ssDSSCs device showed an impressive 620 mV open circuit photovoltage.

Chapter 6 (paper VII) covers the study of electron transfer mechanisms in a covalently linked dye-catalyst (PB-2) sensitized NiO photocathode, towards hydrogen producing solar fuel devices. Hole injection from excited dye (PB-2*) into NiO VB takes place on dual time scales, and the reduced PB-2 (PB-2●-) formed then donates an electron to the catalyst unit.  The subsequent regeneration efficiency of PB-2 by the catalyst unit (the efficiency of catalyst reduction) is determined to ca. 70%.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2016. 80 p.
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 1418
Keyword
Electron transfer, Laser spectroscopy, Femtosecond spectroscopy, Transient absorption, NiO, DSSCs, DSSFDs, Charge separation, Solar energy conversion, Nanosecond photolysis, Photophysics
National Category
Chemical Sciences
Research subject
Chemistry with specialization in Chemical Physics
Identifiers
urn:nbn:se:uu:diva-302263 (URN)978-91-554-9678-4 (ISBN)
Public defence
2016-10-21, Häggsalen, Ångströmlaboratoriet, Lägerhyddsvägen 1, Uppsala, 13:15 (English)
Opponent
Supervisors
Available from: 2016-09-27 Created: 2016-08-31 Last updated: 2016-10-11

Open Access in DiVA

No full text

Other links

Publisher's full text

Authority records BETA

Zhang, LeiHammarström, Leif

Search in DiVA

By author/editor
Zhang, LeiHammarström, Leif
By organisation
Physical Chemistry
In the same journal
The Journal of Physical Chemistry C
Physical Chemistry

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 495 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf