Mechanochemistry for Energy Materials: Impact of High‐Energy Milling on Chemical, Electric and Thermal Transport Properties of Chalcopyrite CuFeS₂ Nanoparticles

Abstract

Chalcopyrite CuFeS 2 , a semiconductor with applications in chemical sector and energy conversion engineering, was synthetized in a planetary mill from elemental precursors. The synthesis is environmentally friendly, waste-free and inexpensive. The synthesized nano-powders were characterized by XRD, SEM, EDX, BET and UV/Vis techniques, tests of chemical reactivity and, namely, thermoelectric performance of sintered ceramics followed. The crystallite size of ~13 nm and the strain of ~17 were calculated for CuFeS 2 powders milled for 60, 120, 180 and 240 min, respectively. The evolution of characteristic band gaps, Eg, and the rate constant of leaching, k, of nanopowders are corroborated by the universal evolution of the parameter S BET /X (S BET -specific surface area, X-crystallinity) introduced for complex characterization of mechanochemically activated solids in various fields such as chemical engineering and/or energy conversion. The focus on non-doped semiconducting CuFeS 2 enabled to assess the role of impurities, which critically and often negatively influence the thermoelectric properties.

The manipulation of natural mineral chalcopyrite CuFeS2via mechanochemistry: properties and thermoelectric potential

“…In our previous work, the possibility of band gap tuning in high-energy milled chalcopyrite was evidenced for the first time, 61 where the same trend as that observed in the present study was documented. In the cited paper, the mechanical activation was performed by the traditional procedure, i.e.…”

“…In the present study, changes in the revolutions of the mill in the range of 200–600 min −1 (by constant milling time of 60 min) instead of changes caused by just changing the milling time to 60–240 min in the previous study (by constant mill revolutions of 550 min −1 ) were applied. 61 According to, 34 the impact-to-shear ratio of the milling balls is not constant in this case because the regime of ball movement changes.…”

Fabrication of High Quality Bornite and Chalcopyrite Thin Films by Aerosol-Assisted Chemical Vapor Deposition

“…Thus, ρ = 1.6 × 10 –2 Ω·m observed for our thin film is commensurate with their value for synthetic chalcopyrite. Frequently, in the literature, chalcopyrite has been associated with resistivities in the range of 10 –1 to 10 –3 Ω·m ,,− while that of bornite ranges from 10 –2 to 10 –4 Ω·m. ,,,, Our results show that the thin films produced by this technique are of comparable quality to those techniques in terms of their electrical transport properties, potentially at a fraction of the cost of manufacture. Overall, this comparison to literature also highlights the importance of the choice of manfacturing route toward these materials, as the transport properties can vary with orders of magnitude difference between synthetic routes.…”

Mechanochemical one-pot synthesis of heterostructured pentlandite-carbon composites for the hydrogen evolution reaction

“…, during ball milling, and have been shown to be a successful synthesis route for many sulfide and selenide compounds. 25–34 Compared to traditional synthesis methods, the mechanochemical approach has enabled a cost-effective, scalable, and solvent-free production of pentlandite. Yet, to the best of our knowledge, there is no universal approach yielding a wide range of desired Pn compositions and heterostructured materials.…”