A copper-containing oxytelluride as a promising thermoelectric material for waste heat recovery

Synthesis, characterisation and thermoelectric properties of the oxytelluride Bi2O2Te

“…The fluorite-type [Bi 2 O 2 ] 2 þ layers are also found in the related [BiO] [CuTe] oxytelluride, where they alternate with anti-fluorite [Cu 2 Te 2 ] 2 À layers [21]. The two-dimensional square nets of Te atoms found in Bi 2 O 2 Te are a characteristic structural motif in polytelluride compounds.…”

“…Recently, the related oxychalcogenides [BiO][CuQ] (Q¼ S, Se, Te), which consist of [Bi 2 O 2 ] 2 þ layers alternating with [Cu 2 Q 2 ] 2 À layers [17], have been identified as promising p-type thermoelectric materials. In this system, it has been shown that the substitution of Se by Te leads to an increase in electrical conductivity [18,19], together with a reduction in the thermal conductivity ( $ 0.97 W m À 1 K À 1 for BiOCuSe [20] and 0.68 W m À 1 K À 1 for BiOCuTe [21] at 373 K). Consequently, the figure of merit of the oxytelluride (ZT¼ 0.42 at 373 K) is significantly higher than that of the oxyselenide (ZT ¼0.15 at 373 K) [20,21].…”

“…In this system, it has been shown that the substitution of Se by Te leads to an increase in electrical conductivity [18,19], together with a reduction in the thermal conductivity ( $ 0.97 W m À 1 K À 1 for BiOCuSe [20] and 0.68 W m À 1 K À 1 for BiOCuTe [21] at 373 K). Consequently, the figure of merit of the oxytelluride (ZT¼ 0.42 at 373 K) is significantly higher than that of the oxyselenide (ZT ¼0.15 at 373 K) [20,21]. In sharp contrast, the effect of substituting Se by Te in Bi 2 O 2 Se is not known, although the existence of a phase with stoichiometry Bi 2 O 2 Te, together with its thermal stability, have been reported by Schmidt et al [9,22,23].…”

Enhanced performances of melt spun Bi2(Te,Se)3 for n-type thermoelectric legs

“…In particular, due to the large consumptions (particularly in CdTe photoelectric industry [14,15]) and a low reserves of tellurium element, it is vital and necessary to explore tellurium-absence or low tellurium-bearing thermoelectric materials to replace the traditional Bi 2 Te 3 -based materials [16]. For n-type Bi 2 Te 3 -based materials, owing to the same crystal structure and similar electronic structure between Bi 2 Te 3 and Bi 2 Se 3 , selenium substitution of tellurium in Bi 2 Te 3 alloy seems to be an effective approach to reduce the usage of tellurium element.…”

Reduced thermal conductivity by nanoscale intergrowths in perovskite like layered structure La2Ti2O7

“…1 They do not possess any moving parts, which make them potentially reliable and long lasting. 2 The efficiency of a thermoelectric material can be represented by a dimensionless figure of merit (zT) which depends on Seebeck coefficient (S), electrical conductivity (r), and thermal conductivity (j).…”