Preparation of nickel sulfide thin films by thermal conversion of nickel xanthate precursors for photocatalytic applications

Description

The production of hydrogen using photo(electro)chemical water splitting is a field of research currently attracting a lot of interest. A promising material for photocatalytic hydrogen production is TiO2, which is non-toxic, robust, cheap, and abundant. However, the use of cocatalysts is necessary to increase the efficiency, as TiO2 suffers from a low absorption in the visible region of the solar spectrum, a fast recombination of photogenerated holes and electrons, and a large hydrogen evolution overpotential. [1] A potential group of compounds, which might be used to replace expensive noble metal cocatalysts, are metal sulfides. They generally exhibit a lower band gap than TiO2 and therefore enable visible light absorption. [2] A facile synthesis method for metal sulfide nanomaterials are single-source precursors such as xanthates, which enable the preparation of nanoparticles or thin films with a good control over stoichiometry, phase and morphology depending on the design of the ligand. [3]
In this poster an investigation of a range of nickel xanthate precursors with different linear or branched residues is shown. The thermal decomposition of the different xanthates is investigated. In addition, different types of structured titania films are prepared and modified with nickel sulfide using the previously mentioned nickel xanthate precursors. The prepared films are characterized using x-ray diffraction and optical and electron microscopy. The application of nickel sulfide as cocatalyst on titania has already been shown in literature to have promising results. [1] Therefore, the next step will be the investigation of the photocatalytic properties of the prepared films using dye degradation experiments as well as hydrogen evolution experiments using sacrificial electron donors.

[1] Zhang, L.; Tian, B.; Chen, F.; Zhang, J. Nickel Sulfide as Co-Catalyst on Nanostructured TiO2 for Photocatalytic Hydrogen Evolution. International Journal of Hydrogen Energy 2012, 37 (22), 17060–17067.
[2] Conesa, J. C. Sulfide-Based Photocatalysts Using Visible Light, with Special Focus on In2S3, SnS2 and ZnIn2S4. Catalysts 2022, 12, 40.
[3] Buchmaier, C.; Glänzer, M.; Torvisco, A.; Poelt, P.; Wewerka, K.; Kunert, B.; Gatterer, K.; Trimmel, G.; Rath, T. Nickel Sulfide Thin Films and Nanocrystals Synthesized from Nickel Xanthate Precursors. J Mater Sci 2017, 52 (18), 10898–10914.

Period	2 Feb 2023
Event title	Advanced Materials Poster Day 2023
Event type	Conference
Location	Graz, AustriaShow on map