A comprehensive review on single source molecular precursors for nanometric group IV metal chalcogenides: Technologically important class of compound semiconductors

Group IV metal chalcogenides (group IV MCs) have garnered significant attention from scientific fraternity owing to their distinct structural features and interesting electronic properties that could be exploited for diverse applications including energy conversion and storage, optoelectronic devices and sensors. However, to make group IV MCs commercially viable, it is imperative to evolve efficient, cost effective and scalable methods for their synthesis. Single source molecular precursor (SSP) mediated synthesis of group IV MCs is one such route which enjoys tremendous advantages over conventional solid state or dual precursor routes. Most importantly, SSP serve as a viable tool to afford phase pure group IV MCs with high reproducibility and excellent control over size and morphology in presence of suitable capping agents. This timely review provides a comprehensive overview of SSPs employed for accessing group IV MCs nanomaterials as well as thin films. Effects of various ligands on SSP performance have been rationalized. Additionally, precursors which can afford selective synthesis of different compositions or phase of group IV MCs by the choice of solvent, temperature and mode of decomposition have been critically assessed. Strength, limitations and opportunities associated with SSP approach are critically evaluated to provide directions for the development of new SSPs. Furthermore, the role of capping agents and fundamentals of viable synthetic strategies in general, for materials synthesis and deposition of thin film have been summarised in this account. Finally, the conclusion and future prospects of SSPs have also been included in this review. It is expected that this review will provide library of precursors and optimized conditions to synthesize group IV MCs and further catch the attention of researchers to explore the SSP mediated route in making size- and shape -tunable nanostructures with improved functionalities.