Doping Effect on Cu2Se Thermoelectric Performance: A Review

Abstract

Cu2Se, owing to its intrinsic excellent thermoelectric (TE) performance emerging from the peculiar nature of “liquid-like” Cu+ ions, has been regarded as one of the most promising thermoelectric materials recently. However, the commercial use is still something far from reach unless effective approaches can be applied to further increase the figure of merit (ZT) of Cu2Se, and doping has shown wide development prospect. Until now, the highest ZT value of 2.62 has been achieved in Al doped samples, which is twice as much as the original pure Cu2Se. Herein, various doping elements from all main groups and some transitional groups that have been used as dopants in enhancing the TE performance of Cu2Se are summarized, and the mechanisms of TE performance enhancement are analyzed. In addition, points of great concern for further enhancing the TE performance of doped Cu2Se are proposed.

Synergetic Optimization of Electrical and Thermal Transport Properties by Cu Vacancies and Nanopores in Cu2Se

“…Hence, many efforts have been carried out to further improve ZT values by adjusting the content of Cu vacancies in the past few decades . Element doping has been proven to be one of the most effective approaches to improve the TE performance of Cu 2 Se-based materials . It was reported that doping metal elements (such as Ga, Ni, Al, Br, and so on) − can optimize effectively the hole concentration and significantly improve the TE performance.…”

“…37 Element doping has been proven to be one of the most effective approaches to improve the TE performance of Cu 2 Se-based materials. 38 It was reported that doping metal elements (such as Ga, Ni, Al, Br, and so on) 39−41 can optimize effectively the hole concentration and significantly improve the TE performance. For example, Bailey et al reported a ZT ∼ 1 at 823 K in 1% Sn-doped Cu 2 Se samples.…”

Facile synthesis of copper selenides with different stoichiometric compositions and their thermoelectric performance at a low temperature range

“…30 To further improve the ZT values, nanostructure engineering and elemental doping are considered to be the effective strategies. [35][36][37] The output voltage test of the sintered-Cu 2Àx Se sample was then investigated at 303 K. Fig. 5(a) shows the voltage-time curve of the sintered sample during heating.…”

Some Thermoelectric Phenomena in Copper Chalcogenides Replaced by Lithium and Sodium Alkaline Metals

“…It is well known that Cu 2 Se has an excellent intrinsic TE performance, however, practice shows that alloying with other elements can greatly improve the thermoelectric characteristics of copper selenide. Doping effect on Cu 2 Se thermoelectric performance was reviewed in 2020 by Y. Qin et al [ 202 ]. The authors summed that through doping, many elements, such as Al, Li, Na, In, etc., have caused the ZT value of Cu 2 Se to exceed 2, and almost break through the minimum requirement of commercial use ( ZT > 3).…”