Development of Semi‐Transparent Bifacial Thin Film Solar Cells for Innovative Applications (2021-2023)

Project acronym: BTSC

Project duration: January 2021 – December 2023

Project coordinator – Dr. Vytautas Getautis (Kaunas University of Technology, Kaunas, Lithuania)

Leader of the Latvian partner –Dr. Aivars Vembris (ISSP UL, Riga, Latvia)


Goal of the project is to enhance research‐based knowledge development in Baltic‐Nordic states through cooperation by developing materials for semi‐transparent bifacial cost‐effective solar cells, which operate efficiently in full and faint sunlight, as well as snowy conditions. These solar cells present unlimited potential market applications – from light harvesting in shaded parts of houses to windows of electric cars to architecture. The market potential of these solar cells for residential and commercial solar PV in Nordic and Baltic countries is tremendous. This project builds on the pre‐existing complementary scientific expertise in the related fields of synthesis of novel organic and inorganic hole conductor materials (KTU), their characterization (ISSP UL), thin film deposition and solar cell fabrication (TalTech), materials modelling and defect chemistry by first-principles calculations as well as solar cell device modelling (IFE).

In this project Sb chalcogenide absorbers and solar cell structures will be theoretically modelled to improve understanding of dopant-induced changes in the optoelectronic properties of absorber materials and establish the guidelines for solar cell processing. Sb chalcogenide and metal oxide materials will be deposited by simple, resource‐efficient and area‐scalable methods, e.g. chemical spray pyrolysis, and low-vacuum methods, e.g. closed-space sublimation. Semi‐transparent bifacial thin-film solar cells require development of HTM molecules with characteristics matching the Sb chalcogenide material. Efficient, sufficiently transparent, and deposable by simple spray coating HTM materials will be developed and characterized for these solar cells.

The synergy of joint research collaboration gives novel input to development of such solar cells for innovative applications. The project stimulates collaborative research on EU and regional level and offers splendid possibilities for PhD and postdoctoral students’ research.