Transitional Metal Thiophosphates Based Cathodes for Researchable Aluminium-ion Batteries

Project description

Aluminium-ion batteries (AIB) is a promising alternative to Li-ion batteries, due to the abundance of aluminium in the earth’s crust, large gravimetric (2980 mAh/g) and volumetric capacity (8040 Ah/cm3) of aluminium metal anode. Challenges to realizing high power and energy density storage in AIB are associated with the search for suitable cathode materials.
Transitional metal thiophosphates (MPSx, where M is a transitional metal) as AIB cathodes deserve special attention. The MPSx phases were widely studied in the field of electro/photo-catalysis, spintronics and sensors, whereas their applications in energy storage lack fundamental understanding. These materials have layer structures with Van der Waals interlayer gaps of >6 Å, which are suitable for the interrelation of bulky ions or ion complexes. Their facile synthesis via solid-state route and tuneable strength of M-P2S6 bond make MPSx interesting materials for AIB application with a potential to control intercalation/conversion mechanism pathways. Also, the presence of phosphorus in their lattice structure changes their electrochemical reactivity compared to metal chalcogenides analogues.
This project is dedicated to the rational design of stable high capacity cathode materials through understanding the charge storage mechanism of MPSx and controlling different transitional metal cations. More specifically, this project will synthesise C2/m monoclinic (ZnPS3, NiPS3, MnPS3, CrPS4, VPS3), P42/mnm tetragonal (Cu3PS4), and orthorhombic Pmn21 (Cu2P2S6) phases via solid-state route. The obtained materials will be tested in AIBs. The prospective cathode materials will be selected for further optimization by phase exfoliation to the few-layer structure and compositing with guest components.
We will focus on understanding the crystal structure change of MPSx in battery operations and the charge storage mechanism. This will help to understand how to control intercalation versus conversion pathways in MPSx phases upon variation of the strength of M-P2S6 bond, charging protocols, and selected electrolytes.

Outcomes

1. A new family of MPSx based cathode materials with high capacities for AIBs.
2. New knowledge on the competition of intercalation versus conversion pathways for AIB cathode mechanism.
3. New insights on the relationship between MPSx structures (e.g. M-P2S6 bond strength, crystal phase, nanostructures) and the cathode performances/mechanisms.

Essential capabilities

Demonstrated knowledge in nanotechnology, materials science, and electrochemical analysis skills

Desireable capabilities

Demonstrated knowledge of battery storage technology

Expected qualifications (Course/Degrees etc.)

Master degree in the discipline area

Candidate Discipline

Functional Materials Nanotechnology Battery Energy Storage.