Exploring the IR-limit of the triplet-triplet annihilation upconversion: Tetraaryltetraanthra[2, 3] porphyrin - Family

The main advantage of the techniques, using photon conversion is that conversion processes and devices can be considered and optimized independently, without affecting the particular physical properties of the operating photovoltaic material or device architectures [1]. Up to now the triplet-triplet annihilation-supported upconversion (TTA - UC) is the only upconversion process excited with moderate concentrated sunlight. Our group demonstrates UC device based on family of symmetrical tetraaryltetraanthra[2, 3]porphyrins sensitizers, efficiently transforming the IR-A part of the sun spectrum into the VIS-range, operating under moderate concentrated sunlight (50 suns, AMI.5). Next important requirement is protection of UC-molecular system from the ambient oxygen. Our group demonstrates oxygen scavenging formulations, well-suited for the TTA - UC process. Compatibility between the UC device and the photovoltaic device (PV), including the subject of optical coupling is discussed.