High thermoelectric efficiency in electrodeposited silver selenide films: from Pourbaix diagram to a flexible thermoelectric module

Abstract

In the last years, to explore new thermoelectric materials with low-toxicity, earth-abundant, and high-efficiency has become essential. Following this trend, sustainable, easily scalable, and cost-effective fabrication methods, such as electrochemical...

Advances in Ag2Se-based thermoelectrics from materials to applications

“…Additionally, the electrochemical deposition method was employed to fabricate Ag 2 Se-based films with different compositions by adjusting the reduction potentials. The electrodeposited Ag 1.8 Se film exhibits an S 2 σ of 25.37 ± 5.23 μW cm −1 K −2 at room temperature, 128 which is comparable with that of the state-of-the-art Ag 2 Se-based films. Compared with the stoichiometric Ag 2 Se bulk material, the stoichiometric Ag 2 Se film exhibits a similar S 2 σ at room temperature but a much higher S 2 σ of ∼47 μW cm −1 K −2 at ∼380 K. Such a large difference indicates that some novel mechanisms may exist in Ag 2 Se-based films.…”

“…Additionally, the electrochemical deposition method was employed to fabricate Ag 2 Se-based films with different compositions by adjusting the reduction potentials. The electrodeposited Ag 1.8 Se film exhibits an S 2 s of 25.37 AE 5.23 mW cm À1 K À2 at room temperature, 128 In addition to the stoichiometric ratio modulation that mainly influences n, realizing preferred crystal orientation can impact m and phonon transport behaviours, therefore optimizing the thermoelectric performance. 99 The first principles DFT was employed to study the thermoelectric performance of the a-Ag 2 Se single crystal from 160 to 300 K. 99 The theoretical result indicated that S 2 s along the b-axis direction reached B24.65 mW cm À1 K À2 at room temperature, which is around two orders of magnitude larger than that along the a and c axes.…”

“…1(b) compares the maximum power factor S 2 s max of Ag 2 Se-based thermoelectric films reported in recent years. These films include pure Ag 2 Se films with stoichiometric ratio manipulation [126][127][128][129] and anisotropic modulation; 130,131 organic/Ag 2 Se hybrid films; [132][133][134][135] inorganic/Ag 2 Se hybrid films [136][137][138][139] and printed Ag 2 Se films. [140][141][142] As can be seen, Ag 2 Se-based films exhibit considerably high electrical transport performance, and the S 2 s max values of B80% of films exceed 10 mW cm À1 K À2 , which are higher than those of most flexible thermoelectric films.…”

“…Fig.1(a) Temperature-dependent ZT values of Ag 2 Se-based bulk materials [112][113][114][117][118][119][120][121][122][123][124][125]. (b) Maximum power factor S 2 s max of Ag 2 Se-based films 99,[126][127][128][129][130][131][132][133][136][137][138]140,141,[144][145][146][152][153][154][155][156]. (c) Maximum power density o max of Ag 2 Se-based devices 127,[129][130][131][132][133][134]136,137,140,[144][145][146][147].…”

Recent Advances in the Nanomaterials, Design, Fabrication Approaches of Thermoelectric Nanogenerators for Various Applications

“…[91,92] Recent works have shown the potential of Ag 2 Se to replace the more efficient but brittle Bi 2 Te 3 materials for flexible TEGs. [88,93,94] For example, Jiang et al [27] fabricated a flexible TENG based on n-type Ag 2 Se with a polyvinylpyrrolidone (PVP) binder material for portable electronics and IoT applications. The Ag 2 Se alloy was coated with a thin layer of PVP via vacuum filtration through a nylon membrane followed by hot pressing, yielding a flexible film comprised of randomly dispersed micropores.…”