The objective of subproject IREC is the development and demonstration of solar cells that are transparent in the red-near infrared (NIR) range (1.5-2.0 eV) and based on the implementation of optimized wide bandgap and low dimensionality chalcogen absorber layers. More specifically, the project is focused on chalcogen systems based on Sb2(Se,S)3 absorber layers compatible with devices with >18% efficiency and on other materials identified as potentially suitable during the development of the subproject UB. The strategies that will be implemented for the optimization of these systems include investigating annealing processes and doping with different elements (with a focus on alkalines) in the case of the absorber layer, as well as optimizing the absorber-buffer layer heterojunction and the application of selective hole/electron barrier layers developed in subprojects UPC and UJI in the case of the complete photovoltaic systems.
The activities that will be developed in the subproject include: i) contributing to the absorber material screening carried out in subproject UB; ii) modelling and designing optimum PV device architectures pursuing a balance between bandgap (in the 1.5-2.0 eV range) and layer thickness, and identifying heterojunctions with an optimum band alignment; iii) optimization of the absorber layers (based on Sb2(Se,S)3 and on the compounds identified in subproject UB) synthesized through processes compatible with their application in industrial environments and based on the deposition of metallic precursor layer by sputtering followed by reactive annealing treatments, as well as on the development of controlled etching processes for precisely tuning the thickness of the layers; iv) development of specific buffer layers for the different absorber layers developed in the project with optimum thickness and composition and based on CBD, sputtering and ALD processes (including Zn(O,S), (Cd,Zn)S, ZnMgO and ZnSnO layers); v) implementation of devices based on an absorber/selective contacts (developed in subprojects UPC and UJI) architecture; vi) the development and advanced optoelectronic
characterization of complete photovoltaic system (solar cell) prototypes that integrate the different layers developed in the project and fabricated on rigid and flexible transparent substrates for the demonstration of the quantitative objectives of the project and for the demonstration of a functional system suitable for agrivoltaic applications with 10% efficiency.
This subproject will have a strong interaction with two H2020 European projects on which IREC is currently participating: INFINITE-CELL (GA 77968, www.infinite-cell.eu), coordinated by IREC and focused on the development and optimization of efficient photovoltaic technologies for tandem applications; SENSATE (GA 866018) ERC-CoG H2020, focused on boosting the efficiency of solar cells employing low dimensionality materials; and Tech4Win (GA 826002, www.tech4win.eu), coordinated by IREC and focused in the
development of new transparent PV concepts based on oxides. These projects will enable a direct interaction with the main reference research centers in an international level that are currently leading the R&D&i activities in Europe in these fields. Furthermore, ambitious dissemination plans are proposed for the dissemination and exploitation of the project contributing to the general impact of these new technologies in the society.
Este proyecto ha sido financiado a cargo del Programa Estatal de Generación de Conocimiento y Fortalecimiento Científico y Tecnológico del Sistema de I+D+i y de I+D+i Orientada a los Retos de la Sociedad, en el marco del Plan Estatal de Investigación Científica y Técnica y de Innovación 2017-2020. Financiado por el Ministerio de Ciencia e Innovación (MICINN) a través de la Agencia Estatal de Investigación.