Research

Perovskite solar cells have attracted global attention for their high efficiencies and ease of processing. The most promising material is hybrid organic-inorganic lead iodides. Despite its success, there are significant drawbacks to these materials. By adapting the ionic radius concept to apply to heavier halides, we showed that few if any new hybrid halide perovskite materials will be stable (Chem. Sci. 2016). By moving away from the perovskite structure, a huge compositional parameter space is opened up. 

One possibility is the use of optically active organic groups in place of small organic ions (Inorg. Chem. 2016). 

Another direction is the use of structures closely related to perovskite, such as vacancy ordered perovskites with compositions A2BX6 or A3B2X9. We study the fundamental structural and optical properties of such materials (Chem. Mater. 2019, Chem. Mater. 2020, Chem. Sci. 2021, J. Mater. Chem. C., 2022 )

We have found halide materials have uses away from photovoltaics, for example, in electrocatalysis. We used XPS to study how the surface passivation of a halide perovskite electrode is dependent on A site composition, which in turn strongly affects peroformance (ACS Appl. Mater. Interfaces, 2023)

We study ionic liquids (ILs) for battery electrolyte applications. ILs can have advantages of superior stability, electrochemical window and safety compared with standard organic electrolytes.

We synthesise and characterise ILs (New J. Chem. 2021, PCCP 2021) and use in situ electrochemical XPS to understand their behaviour during charging discharge cycles.