Iron-Based Dye-Sensitized Solar Cells - From Theory to Working Solar Cell
(2019) KASM10 20182Centre for Analysis and Synthesis
- Abstract
- In the hunt for fossile-free energy-harvesting techniques, solar cells constitute one of the most promising techniques. Today, silicon-based solar cells are the dominant technique on the market but even the Silicon solar cell has limitations which means that there is a motivation for developing new solutions. One of those techniques is the dye-sensitized solar cell. Just as in photosynthesis, the solar cell contains a dye molecule that when absorbing the light from the sun can separate an electron from an electron hole. The electron is injected into titania and from there extracted as current. In this Master's thesis, two new dye molecules called FeCAB26 and FeCABCN2 have been investigated by spectroscopic methods (absorption spectroscopy,... (More)
- In the hunt for fossile-free energy-harvesting techniques, solar cells constitute one of the most promising techniques. Today, silicon-based solar cells are the dominant technique on the market but even the Silicon solar cell has limitations which means that there is a motivation for developing new solutions. One of those techniques is the dye-sensitized solar cell. Just as in photosynthesis, the solar cell contains a dye molecule that when absorbing the light from the sun can separate an electron from an electron hole. The electron is injected into titania and from there extracted as current. In this Master's thesis, two new dye molecules called FeCAB26 and FeCABCN2 have been investigated by spectroscopic methods (absorption spectroscopy, emission spectroscopy and transient absorption spectroscopy), quantum-chemical calculations and electrical measurements with the purpose to investigate the potential for usage as sensitizers in dye-sensitized solar cells. The molecules are iron-carbene-complexes, synthesized by colleges at Lund University, which are at the frontier of this research field since many traditionally used sensitizers have been ruthenium-complexes.
Both molecules were able to sensitize films of titania and absorb light in the visible part of the spectrum. Quantum-chemical calculations indicated that the molecules did excite an electron from metal-centred orbitals to ligand-centred orbitals upon absorption of light. The molecules did also inject electrons into
titania via the excited metal-to-ligand charge transfer state. The excited states had lifetimes of 21 ps and 36 ps for the different molecules. When the dye molecules were used as sensitizers in solar cells, a photocurrent was measured upon illumination in a solar simulator for the molecule FeCABCN2. Without
having optimized the fabrication process, the efficiency of the best solar cell was 0.13 %. This shows a proof of concept that FeCABCN2 could work as a sensitizer in DSSCs. The optical characterization of both molecules will contribute to the development of iron-carbene-complexes as dye molecules to be used for applications in a broader context than just solar cells. (Less) - Abstract (Swedish)
- I jakten på förnyelsebara energikällor är solceller en av de mest lovande teknikerna. Idag dominerar kisel-solcellen marknaden men även den har begränsningar och därför är det motiverat att utveckla andra sorters solceller. En solcellsteknik på utvecklingsstadiet som försöker efterlikna fotosyntesen är
Grätzelsolcellen. Precis som i fotosyntesen är det en färgämnesmolekyl i solcellen som ska absorbera solens ljus och separera en elektron från ett elektronhål genom att elektronen skickas från färgämnesmolekylen till en titandioxid-elektrod och därifrån extraheras som elektrisk ström. I detta masterarbete har två nya färgämnesmolekyler kallade FeCAB26 och FeCABCN2 undersökts genom en rad spektroskopiska (absorptionsspektroskopi,... (More) - I jakten på förnyelsebara energikällor är solceller en av de mest lovande teknikerna. Idag dominerar kisel-solcellen marknaden men även den har begränsningar och därför är det motiverat att utveckla andra sorters solceller. En solcellsteknik på utvecklingsstadiet som försöker efterlikna fotosyntesen är
Grätzelsolcellen. Precis som i fotosyntesen är det en färgämnesmolekyl i solcellen som ska absorbera solens ljus och separera en elektron från ett elektronhål genom att elektronen skickas från färgämnesmolekylen till en titandioxid-elektrod och därifrån extraheras som elektrisk ström. I detta masterarbete har två nya färgämnesmolekyler kallade FeCAB26 och FeCABCN2 undersökts genom en rad spektroskopiska (absorptionsspektroskopi, emissionsspektroskopi, tidsupplöst laserspektroskopi), beräkningskemiska och
elektriska mätmetoder med målet att bestämma deras fotofysiska egenskaper och bedöma dugligheten för bruk i Grätzelsolceller. Färgämnesmolekylerna är båda järnkarben-komplex, syntetiserade av kollegor vid Lunds universitet, vilka är i framkanten av forskningen inom detta fält där många metallbaserade färgämnesmolekyler annars varit rutenium-komplex.
Båda molekylerna visade sig fästa till titandioxidytor och absorbera ljus i det synliga våglängdsområdet. De kvantkemiska beräkningarna indikerade att färgämnesmolekylerna vid absorption av ljus exciterade en elektron i en metall-centrerad orbital till ligand-centrerade orbitaler. De exciterade tillstånden hade livstider på 21 ps respektive 36 ps. Färgämnesmolekylerna visade sig även injicera elektroner i titandioxiden vid belysning. När färgämnesmolekylerna införlivades i solceller, så kunde en elektrisk ström mätas under belysning i solsimulator för FeCABCN2. Utan att ha optimerat tillverkningsprocessen var effekten för de bästa solcellerna med FeCABCN2 runt 0,13 %. Som ett första steg visar detta att FeCABCN2-färgämnet principiellt sett fungerar, även om fortsatt utveckling mot bättre solceller av denna typ kräver omfattande fortsatt forskning. Karaktäriseringen av båda molekylernas optiska egenskaper bidrar även till den fortsatta utvecklingen av järnkarben-komplex som färgämnesmolekyler mer generellt. (Less) - Popular Abstract
- Solar energy is a renewable energy source harvested by solar cells. But even if there are functioning solar cells on the market, the hunt for even better ones are engaging many scientists. This project has contributed in the development of a solar cell inspired by nature, that is using simple compounds to form the versatile solar cell of tomorrow: a solar cell that is environmentally friendly, can have different colours and can be made bendable.
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/8970251
- author
- Lindh, Linnea LU
- supervisor
-
- Pavel Chabera LU
- Petter Persson LU
- organization
- course
- KASM10 20182
- year
- 2019
- type
- H2 - Master's Degree (Two Years)
- subject
- keywords
- Dye-sensitized solar cells, Grätzel cells, solar cells of the future, solar cells of tomorrow, spectroscopy, time-resolved spectroscopy, materials chemistry, materialkemi
- language
- English
- id
- 8970251
- date added to LUP
- 2019-02-22 15:21:03
- date last changed
- 2019-02-22 15:21:03
@misc{8970251,
abstract = {{In the hunt for fossile-free energy-harvesting techniques, solar cells constitute one of the most promising techniques. Today, silicon-based solar cells are the dominant technique on the market but even the Silicon solar cell has limitations which means that there is a motivation for developing new solutions. One of those techniques is the dye-sensitized solar cell. Just as in photosynthesis, the solar cell contains a dye molecule that when absorbing the light from the sun can separate an electron from an electron hole. The electron is injected into titania and from there extracted as current. In this Master's thesis, two new dye molecules called FeCAB26 and FeCABCN2 have been investigated by spectroscopic methods (absorption spectroscopy, emission spectroscopy and transient absorption spectroscopy), quantum-chemical calculations and electrical measurements with the purpose to investigate the potential for usage as sensitizers in dye-sensitized solar cells. The molecules are iron-carbene-complexes, synthesized by colleges at Lund University, which are at the frontier of this research field since many traditionally used sensitizers have been ruthenium-complexes.
Both molecules were able to sensitize films of titania and absorb light in the visible part of the spectrum. Quantum-chemical calculations indicated that the molecules did excite an electron from metal-centred orbitals to ligand-centred orbitals upon absorption of light. The molecules did also inject electrons into
titania via the excited metal-to-ligand charge transfer state. The excited states had lifetimes of 21 ps and 36 ps for the different molecules. When the dye molecules were used as sensitizers in solar cells, a photocurrent was measured upon illumination in a solar simulator for the molecule FeCABCN2. Without
having optimized the fabrication process, the efficiency of the best solar cell was 0.13 %. This shows a proof of concept that FeCABCN2 could work as a sensitizer in DSSCs. The optical characterization of both molecules will contribute to the development of iron-carbene-complexes as dye molecules to be used for applications in a broader context than just solar cells.}},
author = {{Lindh, Linnea}},
language = {{eng}},
note = {{Student Paper}},
title = {{Iron-Based Dye-Sensitized Solar Cells - From Theory to Working Solar Cell}},
year = {{2019}},
}