The structure of ga₂te₃an x-ray and high-resolution electron microscopy study

Significantly enhanced thermoelectric figure of merit through Cu, Sb co-substitutions for Te in Ga2Te3

“…One cell projected on (110) is shown with the sizes of $0.4 nm 0.5 nm, which are comparable to those in Ref. 15. An insert in Fig.…”

“…After sintering of the powders, the sintered compact was annealed at 390 C for another 24 h to prevent the formation of Ga 2 Te 5 and reduce GaTe impurity phases because the GaTe (Ga 2 Te 5 ) crystallizes (forms) easily as T cools down (elevates) to 850 C (407 C) in the Ga 2 Te 3 based alloy systems. 15 Detailed experimental procedures have been reported elsewhere. 16 The Seebeck coefficients (a) and electrical conductivity (r) were measured as a function of temperature a) Electronic mail: cuijiaolin@163.com.…”

Effect of Vacancy Distribution on the Thermal Conductivity of Ga2Te3 and Ga2Se3

“…7 It has been expected that Ga 2 Te 3 and Ga 2 Se 3 have a mesoscopic superstructured phase, having vacancy planes. 8,9 In our previous studies, 10,11 the existence of regularly arranged two-dimensional (2D) vacancy planes with approximately 10 lattice (equivalent to 3.5 nm) intervals was confirmed in Ga 2 Te 3 . 10 Furthermore, in solid solutions of (Ga,In) 2 Te 3 , such vacancy planes also existed, but the periodicity of the intervals was random.…”

Thermoelectric Characterization of (Ga,In)2Te3 with Self-Assembled Two-Dimensional Vacancy Planes

“…Desai et al demonstrated that In 2 Te 3 has two components, a low-temperature a-phase with regularly ordered vacancies and a high-temperature b-phase with fully disordered vacancies; the former transforms to the latter at about 893 K. 11 a-In 2 Te 3 has a facecentered cubic lattice with a = 1.850 nm, which is approximately three times the lattice parameter of b-In 2 Te 3 (a = 0.616 nm). On the other hand, it has been observed that Ga 2 Te 3 has a mesoscopic superstructured phase, having periodic vacancy planes, 12,13 as observed in Ga 2 Se 3 . 14 We hypothesized that, if we could create such vacancy planes in the bulk samples and control their size and periodicity, we could achieve a low j, due to the effective phonon scattering by the vacancy planes.…”