Final Report Summary - POLYDOT (Control of the Electronic Properties in Hybrid- Quantum Dot/Polymer-Materials for Energy Production)
The PolyDot project (Control of the Electronic Properties in Hybrid-Quantum Dot/Polymer-Materials for Energy Production) has focused on the study of charge transfer processes in semiconductor quantum dot based solar cells under working conditions.
The project has evaluated different types of solar cells:
- Semiconductor quantum dots/ semiconductor polymer bulk-heterojunction solar cells.
- Dye Sensitized Solar Cells using semiconductor quantum dots as light harvesting materials.
- Semiconductor quantum dots/semiconductor organic materials in bi-layer type solar cells.
In all cases, the interfacial charge transfer recombination processes at the different device interfaces were measured using already existing methods alike Laser Transient Absorption Spectroscopy (L-TAS) and Time Correlated Single Photon Counting (TCSPC). Yet, those methods that have been often used cannot give detailed experimental information about the charge transfer processes that limit the solar cell performance under standard sun-simulated conditions. In PolyDot , our group has adapted and developed new techniques such as PICE (Photo-Induced Charge Extraction) and PIT-PV ( Photo-induced Transient PhotoVoltage) that can (a) measure the charge recombination in complete quantum dot based solar cells at 1 sun conditions (100mW/cm2 sun-simulated light), (b) measure the charge accumulated at different light illumination conditions and (c) compare, tacking into account the same number of accumulated charge at the solar cell, different devices that have different performances.
Why is this important? If we can understand the charge transfer reactions that control the device photocurrent, photovoltage and fill factor we will obtain a correlation between device efficiency and charge transfer mechanisms relationship and progress towards optimized solar cells with efficiencies near to the maximum theoretical value.
PolyDot has been a useful tool to discover charge transfer reactions and their influence on the solar cell parameters never taken into account before. For example, the importance of non-geminate recombination reactions over the final solar cell Voc (open circuit voltage) and the less important effect of electric fields in bi-layer type solar cells using quantum dots and organic semiconductor materials such as fullerene.
Moreover, as project “spin-off” of new ideas, PolyDot has served as platform for the development of a nano-probe for the detection of cystic fibrosis in humans using well-know photoluminescence techniques based on the Förster resonant energy transfer process (FRET) between semiconductor quantum dots and other luminophores. The enzymatic activity of trypsin can be monitored at biological relevant concentrations to discriminate between patients that are homozygotic or heterozygotic for the cystic fibrosis human disease.
The project has evaluated different types of solar cells:
- Semiconductor quantum dots/ semiconductor polymer bulk-heterojunction solar cells.
- Dye Sensitized Solar Cells using semiconductor quantum dots as light harvesting materials.
- Semiconductor quantum dots/semiconductor organic materials in bi-layer type solar cells.
In all cases, the interfacial charge transfer recombination processes at the different device interfaces were measured using already existing methods alike Laser Transient Absorption Spectroscopy (L-TAS) and Time Correlated Single Photon Counting (TCSPC). Yet, those methods that have been often used cannot give detailed experimental information about the charge transfer processes that limit the solar cell performance under standard sun-simulated conditions. In PolyDot , our group has adapted and developed new techniques such as PICE (Photo-Induced Charge Extraction) and PIT-PV ( Photo-induced Transient PhotoVoltage) that can (a) measure the charge recombination in complete quantum dot based solar cells at 1 sun conditions (100mW/cm2 sun-simulated light), (b) measure the charge accumulated at different light illumination conditions and (c) compare, tacking into account the same number of accumulated charge at the solar cell, different devices that have different performances.
Why is this important? If we can understand the charge transfer reactions that control the device photocurrent, photovoltage and fill factor we will obtain a correlation between device efficiency and charge transfer mechanisms relationship and progress towards optimized solar cells with efficiencies near to the maximum theoretical value.
PolyDot has been a useful tool to discover charge transfer reactions and their influence on the solar cell parameters never taken into account before. For example, the importance of non-geminate recombination reactions over the final solar cell Voc (open circuit voltage) and the less important effect of electric fields in bi-layer type solar cells using quantum dots and organic semiconductor materials such as fullerene.
Moreover, as project “spin-off” of new ideas, PolyDot has served as platform for the development of a nano-probe for the detection of cystic fibrosis in humans using well-know photoluminescence techniques based on the Förster resonant energy transfer process (FRET) between semiconductor quantum dots and other luminophores. The enzymatic activity of trypsin can be monitored at biological relevant concentrations to discriminate between patients that are homozygotic or heterozygotic for the cystic fibrosis human disease.