Lohani Ketan, Fanciulli Carlo, Scardi Paolo
Department of Civil, Environmental & Mechanical Engineering, University of Trento, Via Mesiano 77, 38123 Trento, Italy.
Lecco Unit, National Research Council of Italy-Institute of Condensed Matter Chemistry and Technologies for Energy (CNR-ICMATE), Via Previati 1/E, 23900 Lecco, Italy.
Materials (Basel). 2022 Jan 18;15(3):712. doi: 10.3390/ma15030712.
The thermoelectric behavior and stability of CuSnS (CTS) has been investigated in relation to different preparations and sintering conditions, leading to different microstructures and porosities. The studied system is CTS in its cubic polymorph, produced in powder form via a bottom-up approach based on high-energy reactive milling. The as-milled powder was sintered in two batches with different synthesis conditions to produce bulk CTS samples: manual cold pressing followed by traditional sintering (TS), or open die pressing (ODP). Despite the significant differences in densities, ~75% and ~90% of the theoretical density for TS and ODP, respectively, we observed no significant difference in electrical transport. The stable, best performing TS samples reached ~0.45, above 700 K, whereas reached ~0.34 for the best performing ODP in the same conditions. The higher of the TS sintered sample is due to the ultra-low thermal conductivity ( ~0.3-0.2 W/mK), three-fold lower than ODP in the entire measured temperature range. The effect of porosity and production conditions on the transport properties is highlighted, which could pave the way to produce high-performing TE materials.
已针对不同的制备方法和烧结条件对CuSnS（CTS）的热电行为和稳定性进行了研究，这些条件导致了不同的微观结构和孔隙率。所研究的体系是立方多晶型的CTS，通过基于高能反应球磨的自下而上方法以粉末形式制备。将球磨后的粉末分两批在不同的合成条件下进行烧结，以制备块状CTS样品：手动冷压后进行传统烧结（TS），或开模压制（ODP）。尽管密度存在显著差异，TS和ODP分别约为理论密度的75%和90%，但我们观察到电输运方面没有显著差异。稳定的、性能最佳的TS样品在700 K以上达到约0.45，而在相同条件下，性能最佳的ODP样品达到约0.34。TS烧结样品的较高值归因于超低的热导率（约0.3 - 0.2 W/mK），在整个测量温度范围内比ODP低三倍。孔隙率和生产条件对输运性能的影响得到了突出体现，这可能为生产高性能热电材料铺平道路。
