Optical properties of TiS₃ as a novel thin film for single-junction and tandem solar cells

Author(s)

Villegas, Cesar E. P. ; Marinho Jr, Enesio ; Dias, A. C. ; Venezuela, Pedro ; Rocha, Alexandre R.

• Document type: Journal article
• Source: SOLAR ENERGY MATERIALS AND SOLAR CELLS; v. 289, p. 8-pg., 2025-04-25.

Abstract

Sub-micrometer thin films are promising platforms for emerging flexible photovoltaic devices. Although the current market already produces efficient solar cells, the average wafer thickness of these devices remains far from the sub-micrometer scale, making them susceptible to cracking under bending stress and thus precluding their use in flexible device applications. Due to its earth abundance, non-toxicity, and low elastic modulus, titanium trisulfide (TiS3) has emerged as a promising alternative for flexible device applications. Here, using excited-state density functional calculations combined with the transfer matrix approach, we perform an optical analysis and assess the efficiency of a prototype photovoltaic device based on sub-micrometer TiS3 thin films. Using optical constants obtained from our first-principles calculations, we evaluate the photovoltaic response of a single-junction device in the radiative limit, finding that a 140 nm-thick active layer achieves a maximum power conversion efficiency of approximately 22%. Additionally, we investigate tandem solar cells that incorporate TiS3 into perovskite thin films, and find that the lower and upper power conversion efficiencies range from approximately 18% to 33%. Overall, our results suggest great potential for using TiS3 thin films as an active layer in the design of highly efficient flexible solar cells. (AU)

• FAPESP's process: 17/02317-2 - Interfaces in materials: electronic, magnetic, structural and transport properties
• Grantee: Adalberto Fazzio
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 20/13172-8 - Temperature dependence of band gap in hybrid perovskites: a first-principles study
• Grantee: Enesio Marinho da Silva Jr
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 21/13720-8 - 2D Semiconductors for Photovoltaic Applications: Eletron-Phonon and Exciton-Phonon Coupling Effects on Carriers Lifetimes and Optical Properties
• Grantee: Alexandre Reily Rocha
• Support Opportunities: Research Grants - Visiting Researcher Grant - Brazil
• FAPESP's process: 21/14335-0 - ICTP South American Institute for Fundamental Research: a regional center for Theoretical Physics
• Grantee: Nathan Jacob Berkovits
• Support Opportunities: Special Projects