The aim of the present project is the atomic layer deposition of sulphides, and their applications in sensorics, optoelectronics, energy harvesting and storage. The ALD method of the targeted materials, FeSx, MoS2, TiS2, HfS2 and GaSx have only recently been developed, therefore the preparation itself, the optimisation of the deposition parameters is still a challenge. On the other hand all of these materials are important for a number of applications in energy storage and conversion and sensorics. The advantages of ALD, including the precise thickness and compositional control and the conformal coating of complex geometries, make it attractive for the surface engineering of devices.
Iron sulphide can be prepared in the form of FeS and FeS2. The latter is an especially important material for solar cell applications, as its absorbance is very high even in nanometre thickness. It is also a cheap and abundant material. Both FeS and FeS2 can be applied in water splitting both for hydrogen and oxygen generation.
MoS2 is a very versatile semiconducting material used in Li ion batteries as an electrode material, on the other hand, it can also be applied in water splitting for hydrogen generation. Its structure belongs to the transition metal dichalcogenide group. Titanium sulphide and hafnium-sulphide are also transition metal dichalcogenides with layered structures similar to that of MoS2 also very promising for a number of applications.
GaSx is a wide bandgap semiconductor with important photovoltaic and optoelectronic applications also depending on its stoichiometry and structure, and in its nanostructured form it is promising for water splitting as well.