Syntheses and structures of alternative halometallate photovoltaic absorber materials

Abstract

The results described in this thesis concern the design, synthesis and characterisation of new candidate absorber layer sensitizer materials for photovoltaic cells; in particular exploring novel halometallate hybrid structures. Through this work, the field of iodoantimonate and iodobismuthate hybrid materials has been expanded with the discovery and analysis of many novel structures. Alternative, lead-free, antimony and bismuth metal containing hybrid structures are key and of much interest in the rapidly developing area of perovskite-based solar cell architectures. The work undertaken has added to building the database and thus further developing the understanding of hybrid absorber materials with the overarching aim of progressing towards real world thin-film and tandem solar cell designs to challenge and expand upon the industry dominant silicon-based solar cell architectures of today.
An introduction to the field and the context of the research is given in chapter 1, and the relevant experimental techniques are discussed in chapter 2. The remaining chapters of the thesis present the findings of the project as detailed below.
The particular focus of the work carried out covers the discovery and study of the structure and properties of over ten novel iodoantimonate and twenty novel iodobismuthate hybrid materials. The results of the investigations carried out are presented in an alternative thesis format with two full published papers integrated within the narrative in chapter 3. Additionally, as detailed in chapter 4 an in-situ alkylation solvothermal synthetic technique used in the formation of more complex templating agents was found and used to great effect throughout the synthesis and study of iodoantimonate and iodobismuthate novel halometallate hybrid materials. Moreover, a promising opening for a new avenue of perovskite structure potential was uncovered; triggered by the discovery and preliminary analysis of an unfamiliar novel three-dimensional superoctahedra-octahedra linked halometallate motif described in chapter 5.
Outside of this, work was undertaken on other alternative candidate material areas such as bismuth-based coordination complexes, bismuth sulphide iodide, double perovskites and related structures; contained within chapter 6. To finish, the overall results and thesis conclusions are discussed in chapter 7.

Date of Award	2019
Original language	English
Awarding Institution	University of Bath
Supervisor	Mark Weller (Supervisor) & Andrew Johnson (Supervisor)