卤化银AgCl和AgBr的超高热电优值
Superhigh thermoelectric figure of merit in silver halides AgCl and AgBr from first principles
摘要：
寻找高性能的热电材料一直是热电领域的一个梦想。近年来，实验发现，$2.6$在SnSe晶体和Cu 2Se样品中的ZT值分别在923 K和850 K时达到最大值，引起了人们对寻找高ZT材料的极大兴趣。基于第一性原理计算和玻尔兹曼输运方程（BTE），本文报道了岩盐结构的卤化银（AgCl和AgBr）具有优良的TE性能。p型掺杂AgCl和AgBr晶体在中温（~ 600 K）下获得了约7.0的超高ZT，远远超过了目前所有体TE材料的ZT值。这一破纪录的ZT值归因于超低的本征晶格热导率κ_L（例如，AgCl和AgBr在600 K时的κ_L分别为约0.10和0.09 Wm^{-1}K^{-1}）。我们的研究结果可能是一个壮举，可以彻底改变热能转换领域。
英文摘要：
Searching for the high-performance thermoelectric (TE) materials has always been a long-held dream in the thermoelectricity field. Recently, it is found in experiments that the largest figure of merit ZT of $2.6$ can be reached in SnSe crystals at 923 K and Cu2Se sample at 850 K, which arouses the enormous interest of seeking high-ZT materials. Based on first-principle calculations and Boltzman transport equation (BTE), we report in this letter that silver halides (AgCl and AgBr) in rocksalt structure have excellent TE performances. A superhigh ZT of about 7.0 at mid-temperature (~600K) is obtained in the p-type doped AgCl and AgBr crystals, which far exceeds the ZT values of all current bulk TE materials. This record-breaking ZT value is attributed to the ultralow intrinsic lattice thermal conductivity κ_L (e.g. κ_L ~0.10 and 0.09 Wm^{-1}K^{-1} for AgCl and AgBr at 600 K, respectively). Our results may be a feat that could revolutionize the field of the heat energy conversion.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
