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In this study, we demonstrate a one-pot mechanochemical synthesis of the nanocomposite composed of stannite Cu2FeSnS4 and rhodostannite Cu2FeSn3S8 nanocrystals using a planetary ball mill and elemental precursors (Cu, Fe, Sn, S). By this approach, unique nanostructures with interesting properties can be obtained. Methods of XRD, Raman spectroscopy, UV-Vis, nitrogen adsorption, SEM, EDX, HRTEM, STEM, and SQUID magnetometry were applied. Quaternary tetragonal phases of stannite and rhodostannite with crystallite sizes 18–19 nm were obtained. The dominant Raman peaks corresponding to the tetragonal stannite structure corresponding to A-symmetry optical modes were identified in the spectra. The bandgap 1.25 eV calculated from UV-Vis absorption spectrum is very well-acceptable value for the application of the synthesized material. The SEM micrographs illustrate the clusters of particles in micron and submicron range. The formation of agglomerates is also illustrated on the TEM micrographs. Weak ferromagnetic properties of the synthesized nanocrystals were documented

Nanocrystalline CuInS particles have been synthesized from copper, indium, and sulfur powders by high-energy milling in a planetary mill in an argon atmosphere. Structural characterization of the prepared nanoparticles, including phase identification, Raman spectroscopy, specific surface area measurement, and particle size analysis were performed. The optical properties were studied using UV–Vis absorption and photoluminescence (PL) spectroscopy. The production of CuInS (JCPDS 027-0159) particles with a crystallite size of about 17.5–23.5 nm was confirmed by X-ray diffraction. The crystal structure has a tetragonal body-centered symmetry belonging to the I-42d space group. The Raman spectra also proved the formation of pure CuInS nanoparticles. TEM and HRTEM measurements revealed the presence of nanoparticles of different dimensions (10–20 nm) and their tendency to form agglomerates. The nanoparticles tend to agglomerate due to their large specific surface area. The average size of the synthesized particles was determined by photon cross-correlation spectroscopy to be in the range of 330–530 nm (bimodal size distribution). The band gap of the CuInS particles is 2 eV which is wider than that in bulk materials. The decrease in size leads to the blue-shift of the PL spectra. Therefore, CuInS nanoparticles are promising candidates for optical applications, and they have high potential in solar energy conversion., The support through the Slovak Grant Agency VEGA (projects 2/0027/14, 1/0439/13, 2/0051/14) and APVV 14-0103 is gratefully acknowledged. The authors also acknowledge the support of the European Union through the CT-2011-1-REGPOT285895 AL-NANOFUN project (Advanced Laboratory for the Nano-Analysis of novel Functional materials), for the microscopy facilities sited at the Institute of Materials Science in Seville.