The Equilibrium and Free Surface Sublimation Pressures of Oriented Single Crystals of Bismuth Telluride

Abstract

The equilibrium and free surface sublimation pressures of bismuth telluride were determined by the torsion‐effusion and torsion‐Langmuir techniques, respectively. Based on a least‐square fit, the expression for the equilibrium pressure in the temperature range of 722°–828°K was found to be: logP false(normalatmfalse)=false(7.579±0.373false)−false(1.020±0.029false)104/T , where T is the absolute temperature and the given uncertainties are the standard deviations. A similar treatment of the results of free surface pressure over basal plane oriented single crystals gave the following expression for the apparent total pressure in the temperature range of 741°–793°K: logP false(normalatmfalse)=false(10.312±0.693false)−false(1.280±0.053false)104/T . Assuming the sublimation reaction Bi2Te3 false(Sfalse)=2 normalBiTe false(normalgfalse)+½Te2 false(normalgfalse) , average third‐law enthalpies and activation enthalpies of sublimation at 298°K were found to be 127.4±1.2 normaland 133.1±1.8 normalkcal/normalmole , respectively. Calculated values of the sublimation coefficient varied from 0.14 at 722°K to 0.39 at 828°K.

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“…应并沉积一层薄的钝化膜, 称为固态电解质膜, 也叫 SEI膜 [14] . Dey等于1970年发现了SEI膜的实际存在 [15] , 其组成和形成原理极为复杂 [16] . SEI膜是Li + 的良导体, 电子绝缘体, 能够有效抑制电解液进一步分解 [17] , 因 而稳定的SEI膜对电池的循环稳定性至关重要.…”