A Tunable Structural Family with Ultralow Thermal Conductivity: Copper-Deficient Cu_1–x□_xPb_1–xBi_1+xS₃

Abstract

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Lone Pair Rotation and Bond Heterogeneity Leading to Ultralow Thermal Conductivity in Aikinite

“…Therefore, in copper-deficient materials, such as CuPbBi 5 S 9 , n -type electrical conduction involves the Bi–S network, as previously discussed by Maji et al. …”

“…Despite the large number of minerals in the aikinite-bismuthinite series, little is known about the electrical and thermal transport properties of these materials, with the exception of those of Bi 2 S 3 and CuPbBi 5 S 9 , , which are n- type semiconductors. Here, we present a detailed study of the structure and transport properties of aikinite, CuPbBiS 3 , from experimental and theoretical points of view.…”

Engineering Transport Properties in Interconnected Enargite‐Stannite Type Cu2+xMn1−xGeS4 Nanocomposites

“…Only traces of CuS impurities (white contrast) are detected in x =0.5 sample (Figure 7f) which suggests the limit of solubility is reached. Such small isotropic grains are typically observed in copper‐based sulfide compounds prepared by mechanical alloying combined with spark plasma sintering at relatively low temperature (873 K or lower) [32–34] . Interestingly, when increasing x , the grain size increases and the shape becomes more elongated.…”

“…Such small isotropic grains are typically observed in copper-based sulfide compounds prepared by mechanical alloying combined with spark plasma sintering at relatively low temperature (873 K or lower). [32][33][34] Interestingly, when increasing x, the grain size increases and the shape becomes more elongated. A mixture of isotropic and anisotropic grains is observed for all compositions, with a majority of elongated grains for x � 0.3 (Figure 7d-f).…”

Engineering Transport Properties in Interconnected Enargite‐Stannite Type Cu2+xMn1−xGeS4 Nanocomposites

“…Such small isotropic grains are typically observed in copper‐based sulfide compounds prepared by mechanical alloying combined with spark plasma sintering at relatively low temperature (873 K or lower). [ 32 , 33 , 34 ] Interestingly, when increasing x , the grain size increases and the shape becomes more elongated. A mixture of isotropic and anisotropic grains is observed for all compositions, with a majority of elongated grains for x ≥0.3 (Figure 7 d–f).…”