(627e) Batch to Flow Synthesis of Zinc-Indium-Sulfide Nanoparticles

Typically, nanoparticles are synthesised in batch by a variety of methods: hydrothermal; solvothermal; rapid hot injection etc.¹ However, the limitations of batch reactors, such as non-uniform mixing and temperature, can lead to a lack of control over size and chemical composition. Adaptions of batch methods to flow reactors have previously been reported by Dunne et al. for the synthesis of binary metal sulfides.² However, current research into the synthesis of ternary metal sulfides in flow is limited, with only a handful of reports utilising flow technology for these materials.^3,4 Herein, we report a flow methodology to synthesise a range of ternary metal sulfides, Zn_xIn₂S_(m+3) for the first time.

Using flow allows for more precise control over the reaction conditions, such as temperature, residence time, concentration and stoichiometry of the reaction mixture. Therefore, the outcome of the chemical composition and morphology of these materials can be more easily influenced. In particular, increasing the residence time shows significant development of the morphology from nanosheets to nanoflowers, while chemical composition remains constant as determined by Transmission Electron Microscopy/Energy-dispersive X-ray Spectroscopy (TEM/EDX). Additionally, The stoichiometry of the sulfur source appears to be vital for determining the composition of the nanomaterials.

The batch- and flow-synthesised materials were subsequently tested as heterogeneous photocatalysts, and the comparisons of their photoactivites will also be discussed.

References

1. A. Balakrishnan, J. D. Groeneveld, S. Pokhrel and L. Mädler, Chem. Eur. J., 2021, 27, 6390–6406.
2. P. W. Dunne, C. L. Starkey, M. Gimeno-Fabra and E. H. Lester, Nanoscale, 2014, 6, 2406–2418.
3. J. Hiemer and K. Stöwe, ChemistryOpen, 2022, 11, e202200232.
4. C. Rivaux, T. Akdas, R. Yadav, O. El-Dahshan, D. Moodelly, W. L. Ling, D. Aldakov and P. Reiss, J. Phys. Chem. C, 2022, 126, 20524–20534.