Unique Synthetic Approach to Low-Dimensional Semiconducting Metal-Sulfide Materials for (Photo)Electrochemical Energy Conversion by Molecular Building Blocks

The unique physical properties of low-dimensional metal sulfide materials have attracted great attention to increase the efficiency of solar energy conversion into electrical energy via (photo)electrochemical reactions and photovoltaic. The ultrahigh surface area of nanostructured semiconductors in combination with their extraordinary physiochemical, electronic and optical properties offer the application as (photo)electrocatalysts.The huge number of active sides of 2D van der Waals materials like transition metal disulfides (TMDC) and monosulfides (MS), as well as their suitable and tunable band gap offer their application in energy conversion devices. The lacking control of large-scale material synthesis corresponding to specific requirements in commercial material formation processes is still challenging, which motivated us to develop a unique synthetic approach to low-dimensional layered materials MS₂(M= Mo^IV, W^IV, Ti^IV, Nb^IV, Ta^IV, Sn^IV), MS (M=Sn^II, Ge^II). A uniform synthesis route of molecular building blocks for controlled formation of (air)stable precursor classes [M{S(C₂H₄)₂NMe}_x] (M = Mo^IV, W^IV, Ti^IV, Sn^IV, x = 2; M = Ge^II, Sn^II, x = 1) was developed. Following a simple synthetic protocol, the reaction of tridentate SNS donor ligand with suitable metal compounds resulted in (air)stable molecular precursors. Their simple thermal decomposition enabled the targeted formation of homogeneous crystalline 2D MoS₂, WS₂, TiS₂, NbS₂, TaS₂, SnS₂ and SnS. The wet chemical syntheses via microwave assisted decomposition of tin based precursors resulted in SnS and SnS₂ particles.<br/>These molecular building blocks provide advances in the synthesis, characterization and applications of these low-dimensional materials for (opto)electronic applications.