Institut für Anorganische Chemie und Analytische Chemie der Johannes Gutenberg-Universität, Duesbergweg 10-14, D-55099 Mainz, Germany.
J Am Chem Soc. 2013 Jan 16;135(2):726-32. doi: 10.1021/ja308627v. Epub 2013 Jan 3.
Inspired by the promising thermoelectric properties of chalcopyrite-like quaternary chalcogenides, here we describe the synthesis and characterization of the solid solution Cu(2)Zn(1-x)Fe(x)GeSe(4). Upon substitution of Zn with the isoelectronic Fe, no charge carriers are introduced in these intrinsic semiconductors. However, a change in lattice parameters, expressed in an elongation of the c/a lattice parameter ratio with minimal change in unit cell volume, reveals the existence of a three-stage cation restructuring process of Cu, Zn, and Fe. The resulting local anisotropic structural disorder leads to phonon scattering not normally observed, resulting in an effective approach to reduce the lattice thermal conductivity in this class of materials.
受黄铁矿型四元硫属化物有前途的热电性能的启发，我们在此描述了固溶体 Cu(2)Zn(1-x)Fe(x)GeSe(4)的合成和特性。在 Zn 被等电子的 Fe 取代时，这些本征半导体中没有引入电荷载流子。然而，晶格参数的变化，表现为 c/a 晶格参数比的伸长和单位晶胞体积的最小变化，揭示了 Cu、Zn 和 Fe 的三阶段阳离子重构过程的存在。由此产生的局部各向异性结构无序导致了通常不会观察到的声子散射，从而有效地降低了这类材料的晶格热导率。
