Materials modelling of antimony chalcogenides solar cells
File(s)
Author(s)
Wang, Xinwei
Type
Thesis
Abstract
Solar photovoltaic technology which converts the energy of sunlight into electricity provides a clean and sustainable solution to the energy crisis. Despite well-established techniques of silicon-based solar cells, the search for next-generation alternatives with low cost and high efficiency continues. Among them, antimony chalcogenides (Sb2X3, X=S/Se) are at the forefront of an emerging class of sustainable photovoltaic materials. Despite notable developments over the past decade, the light-to-electricity conversion efficiency of Sb2X3 has reached a plateau of ~10%. The underlying bottlenecks remain unclear.
This thesis is focused on the simulation of Sb2X3 by first-principles calculations. First, we perform bulk calculations to investigate crystal, electronic, optical and transport properties of Sb2X3. A fundamental understanding of the origin of anisotropy and analysis of dimensionality in Sb2X3 are provided. Then, we systematically study the intrinsic point defects and their possible electron-hole recombination pathways in Sb2X3. We further predict the upper limit to photovoltaic conversion efficiency in Sb2X3 by considering both radiative and non-radiative recombination. The most detrimental defect species are identified, along with some possible strategies to suppress the defect-assisted recombination losses and improve the photovoltaic performance. A microscopic understanding of the efficiency limit of Sb2X3 solar cells is thus provided.
This thesis is focused on the simulation of Sb2X3 by first-principles calculations. First, we perform bulk calculations to investigate crystal, electronic, optical and transport properties of Sb2X3. A fundamental understanding of the origin of anisotropy and analysis of dimensionality in Sb2X3 are provided. Then, we systematically study the intrinsic point defects and their possible electron-hole recombination pathways in Sb2X3. We further predict the upper limit to photovoltaic conversion efficiency in Sb2X3 by considering both radiative and non-radiative recombination. The most detrimental defect species are identified, along with some possible strategies to suppress the defect-assisted recombination losses and improve the photovoltaic performance. A microscopic understanding of the efficiency limit of Sb2X3 solar cells is thus provided.
Version
Open Access
Date Issued
2024-04
Date Awarded
2024-08
Copyright Statement
Creative Commons Attribution NonCommercial Licence
License URL
Advisor
Walsh, Aron
Sponsor
Imperial College London
Publisher Department
Materials
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)