There has been a lot of interest in the use of metal halide perovskites in solar cells and other light-emitting components. This material has also recently attracted a lot of interest for its potential in energy storage devices, particularly lithium-ion batteries and photo-batteries, due to its long charge carrier diffusion length, high charge mobility, high light absorption capacity, non-rigid structure, and variable bandgap. Materials that harvest and store energy are in great demand due to their bifunctional ability to utilise solar energy effectively and perovskite halides are capable of that. When utilised as standard electrodes in lithium batteries, perovskites based on lead-based halides have shown remarkable performance. However, since lead poisoning affects both people and the...[ Read more ]

There has been a lot of interest in the use of metal halide perovskites in solar cells and other light-emitting components. This material has also recently attracted a lot of interest for its potential in energy storage devices, particularly lithium-ion batteries and photo-batteries, due to its long charge carrier diffusion length, high charge mobility, high light absorption capacity, non-rigid structure, and variable bandgap. Materials that harvest and store energy are in great demand due to their bifunctional ability to utilise solar energy effectively and perovskite halides are capable of that. When utilised as standard electrodes in lithium batteries, perovskites based on lead-based halides have shown remarkable performance. However, since lead poisoning affects both people and the environment, it is a serious issue for both consumers and businesses. Therefore, it is critical to investigate stable, lead-free, and eco-friendly metal halide perovskites with desired properties.

In the first project, Cs₃Bi₂I₉, a lead-free all inorganic perovskite halide was used as a photo-electrode to fabricate a photo-rechargeable Li-ion battery that can harvest energy when illuminated without the aid of an external load. Three different current collectors were used to demonstrate the battery performance: copper, fluorine-doped tin oxide (FTO) doped glass, and carbon felt (CF). These current collectors were used to demonstrate the electrode performance in a standard coin cell, as a basic photo-battery with a transparent current collector to explain how it works, and finally as an optimised photo-battery that exhibits competitive metrics with other photo-batteries and achieves a light conversion efficiency (LCE) of 0.43 % for the first photo-charge/discharge.

In the second project, all inorganic zinc based perovskite halides, Cs₂ZnX₄ were synthesized using room-temperature mechanochemical synthesis and investigated as anode materials in Li-ion batteries. These are novel Li-ion battery anodes that combine Abstract high lithium storage capacity with high rates and stability. Further enhancement in performance was achieved by evaporation of thin layer of C₆₀ on the pristine electrode.

The third project evaluates 3D Cs₂NaBiI₆ as a double perovskite halide photo-electrode for Li-ion batteries. The structural change of a bismuth based perovskite halide from 0D Cs₃Bi₂I₉ to 3D Cs₂NaBiI₆ enhanced the electrochemical performance of the electrode leading to an impressive electrochemical performance with higher capacity values. Light conversion efficiencies of up to 0.265% under 1 sun illumination have been achieved for the first discharge/photo-charge which is the second highest efficiency reported so far for PHBATs based on Li-ion batteries.