Proceedings of International Conference on Hybrid and Organic Photovoltaics (HOPV22)
Publication date: 20th April 2022
In order to increase solar cell efficiencies, singlet fission materials could be of great use. In these organic semiconductors, a photoexcited singlet (spin S = 0) exciton state is converted into two triplet (spin S = 1) excitons with roughly half the initial energy. This carrier-multiplication process potentially reduces the thermalisation losses hampering solar power conversion efficiency [1].
The singlet fission process is thought to progress via intermediate triplet-pair states (total spin S = 0, 1 or 2), the properties of which are, however, still largely unknown. We identify several sharp triplet-pair peaks in the low temperature (1.4 K) photoluminescence (PL) spectrum of high-quality TIPS-tetracene (5,12-bis(triisopropylsilylethynyl)tetracene) crystals.
Using magnetic fields up to 30 T, we are able to tune the S = 1 and S = 2 triplet-pair states into resonance with the S = 0 triplet-pairs, resulting in a drastic reduction of the PL intensity at resonant magnetic fields. Surprisingly, the PL reduction can be as large as 90%, much more than the maximum of 50% anticipated before [2,3]. Lifetime measurements of the triplet-pair emission show that this is a dynamic effect, as the lifetime decreases at the resonant field strengths. Combining these findings, we construct a dynamical model where triplet dissociation can only occur via the S = 1 and S = 2 triplet-pair states. These calculations explain the >50% PL reductions and the field dependent triplet-pair PL decay times observed in our experiment.
K. van den Hoven, V.S. Bechai, H. Engelkamp, P.C.M Christianen
High Field Magnet Laboratory (HFML - EMFL), Radboud University, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands.
This work was supported by HFML-RU/NWO-I, member of the European Magnetic Field Laboratory (EMFL).
nanoGe is a prestigious brand of successful science conferences that are developed along the year in different areas of the world since 2009. Our worldwide conferences cover cutting-edge materials topics like perovskite solar cells, photovoltaics, optoelectronics, solar fuel conversion, surface science, catalysis and two-dimensional materials, among many others.
Previously nanoGe Spring Meeting (NSM) and nanoGe Fall Meeting (NFM), MATSUS is a multiple symposia conference focused on a broad set of topics of advanced materials preparation, their fundamental properties, and their applications, in fields such as renewable energy, photovoltaics, lighting, semiconductor quantum dots, 2-D materials synthesis, charge carriers dynamics, microscopy and spectroscopy semiconductors fundamentals, etc.
International Conference on Hybrid and Organic Photovoltaics
International Conference on Hybrid and Organic Photovoltaics (HOPV) is celebrated yearly in May. The main topics are the development, function and modeling of materials and devices for hybrid and organic solar cells. The field is now dominated by perovskite solar cells but also other hybrid technologies, as organic solar cells, quantum dot solar cells, and dye-sensitized solar cells and their integration into devices for photoelectrochemical solar fuel production.
Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics
The main topics of the Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP) are discussed every year in Asia-Pacific for gathering the recent advances in the fields of material preparation, modeling and fabrication of perovskite and hybrid and organic materials. Photovoltaic devices are analyzed from fundamental physics and materials properties to a broad set of applications. The conference also covers the developments of perovskite optoelectronics, including light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.
The International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics (NIPHO) is the best place to hear the latest developments in perovskite solar cells as well as on recent advances in the fields of perovskite light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.