SENSATE will be at See Future PV symposium in Switzerland

Ivan Caño, from the SENSATE team, will present an abstract at the See Future PV symposium, which will take place in the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland from 3th to 5th November.

See Future PV symposium aims to bring together leading experts in the materials science and photovoltaics field to discuss fundamental and applied aspects of materials suitable for earth abundant solar energy production.

The symposium should provide a platform for researchers working on all stages of development of earth-abundant and newly emerging materials for thin film PV, including both experimental and theoretical/computational approaches. The main focus will be on presenting recent and on-going research leading to improved understanding of materials and devices and exploring new directions for more efficient production of solar cells based on earth-abundant materials.

SENSATE team will present a sequential procedure based on the selenization of thermally evaporated Bi/Se layers which has been designed to synthesize SLG/Mo/(Sb1-xBix)2Se3 samples in the compositional range that allows to tune the band-gap between 1 and 1.4 eV.  In order to better understand the underlying mechanisms that lead to the formation of the solid solution, and thus design specific strategies to enhance the properties of the material and improve its photovoltaic performance, thin films with different annealing time and different temperature (T) have been synthesized, offering an overview of the phases that are formed in each step of the synthesis process. It is shown that the binary compounds (rhombohedral r-Bi2Se3 and orthorhombic o-Sb2Se3) are first formed, with the r-Bi2Se3 phase appearing at lower temperatures. Then, as T increases, the rhombohedral phase disappears and the o-Sb2Se3 Bragg reflections experience a shift towards lower 2θ values, indicating a change in the lattice parameters resulting from the formation of (Sb1-xBix)2Se3.

We present clear evidence on how the (Sb1-xBix)2Se3 is forming, and how it decomposes over time. A good understanding of these processes will allow us design specific strategies to overcome the current limitations of (Sb1-xBix)2Se3 thin films and hence unlock its whole potential, aiming at the development of innovative chalcogenides with tuneable optical and electrical properties.