Built-in voltage of organic bulk heterojuction p-i-n solar cells measured by electroabsorption spectroscopy
Source abstract
Abstract
We investigate the influence of the built-in voltage on the performance of organic bulk heterojuction solar cells that are based on a p-i-n structure. Electrical doping in the hole and the electron transport layer allows to tune their work function and hence to adjust the built-in voltage: Changing the doping concentration from 0.5 to 32 wt% induces a shift of the work function towards the transport levels and increases the built-in voltage. To determine the built-in voltage, we use electroabsorption spectroscopy which is based on an evaluation of the spectra caused by a change in absorption due to an electric field (Stark effect). For a model system with a bulk heterojunction of BF-DPB and C60, we show that higher doping concentrations in both the electron and the hole transport layer increase the built-in voltage, leading to an enhanced short circuit current and solar cell performance.
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Research context
OpenAlex topics: Organic Electronics and Photovoltaics · Thin-Film Transistor Technologies · Molecular Junctions and Nanostructures
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Technische Universität Dresden Institut für Angewandte Photophysik, , D-01062 Dresden, Germany
Funding
DFG
References (25)
Show source-provided references
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