A series of substitutional solid solutions W0.98Nb0.02Se2–yTey (y = 0.2, 0.3, 0.4, 0.5) is synthesized and characterized, crystal lattice parameters are refined for phases of different composition. It is shown that the thermoelectric power of substitutional solid solutions based on modified tungsten diselenide W0.98Nb0.02Se2–yQy (y = 0.2, 0.3, 0.4, 0.5; Q = Te, S) depends on the substitutions in the anionic sublattice. The substitution of selenium by tellurium or sulfur in tungsten diselenide leads to an increase in the crystallite sizes. The more substituted atoms in number, the larger the crystallites, both for sulfur and tellurium cases. As the concentration of sulfur or tellurium increases, electrical conductivity and the Seebeck coefficient increase non-monotonically so that the power factor PF increases in substitutional solid solutions. Among the samples of the studied series, compound W0.98Nb0.02Se1.5Te0.5 has the highest PF value of 444.4 µW/m·K2.

中文翻译：

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组成和晶体尺寸对层状二卤化钨热电性能的影响

合成并表征了一系列置换固溶体 W0.98Nb0​​.02Se2–yTey (y = 0.2, 0.3, 0.4, 0.5)，对不同成分的相进行晶格参数细化。结果表明，基于改性二硒化钨 W0.98Nb0​​.02Se2–yQy (y = 0.2, 0.3, 0.4, 0.5; Q = Te, S) 的置换固溶体的热电功率取决于阴离子亚晶格中的置换。在二硒化钨中用碲或硫取代硒导致微晶尺寸增加。对于硫和碲情况，取代的原子数量越多，晶粒越大。随着硫或碲浓度的增加，电导率和塞贝克系数非单调增加，因此置换固溶体中的功率因数 PF 增加。