Nanowires: A route to efficient thermoelectric devices

Abstract

Miniaturization of electronic devices aims at manufacturing ever smaller products, from mesoscopic to nanoscopic sizes. This trend is challenging because the increased levels of dissipated power demands a better understanding of heat transport in small volumes. A significant amount of the consumed energy in electronics is transformed into heat and dissipated to the environment. Thermoelectric materials offer the possibility to harness dissipated energy and make devices less energy-demanding. Heat-to-electricity conversion requires materials with a strongly suppressed thermal conductivity but still high electronic conduction. Nanowires can meet nicely these two requirements because enhanced phonon scattering at the surface and defects reduces the lattice thermal conductivity while electric conductivity is not deteriorated, leading to an overall remarkable thermoelectric efficiency. Therefore, nanowires are regarded as a promising route to achieving valuable thermoelectric materials at the nanoscale. In this paper, we present an overview of key experimental and theoretical results concerning the thermoelectric properties of nanowires. The focus of this review is put on the physical mechanisms by which the efficiency of nanowires can be improved. Phonon scattering at surfaces and interfaces, enhancement of the power factor by quantum effects and topological protection of electron states to prevent the degradation of electrical conductivity in nanowires are thoroughly discussed.

Interfacial Reactivity of the Filled Skutterudite Smy(FexNi1−x)4Sb12 in Contact with Liquid In-Based Alloys and Sn

“…The thermoelectric approach can be employed in different fields dealing with fundamental problems of sustainability and eco-environmental compatibility. Thermoelectric generators (TEGs) can be used in every circumstance where it is essential to produce energy in small volumes and with neither moving parts nor working fluids [1]; alternatively, they can be coupled to traditional energy production technologies in order to recover waste heat where there is a lack of conversion efficiency [2,3]. Moreover, energy harvesting is of the primary importance for the development of the Internet of Things [4,5].…”

Experimental and Numerical Study on the Effect of Interfacial Heat Transfer on Performance of Thermoelectric Generators

“…At present, the development of thermoelectric power generation devices was limited by high cost and low energy conversion rate. The researchers mainly focus on improving the thermoelectric conversion efficiency of thermoelectric materials [7][8][9][10][11][12] and optimizing the thermal management of thermoelectric generation devices [13][14][15][16][17][18]. In terms of improving the conversion rate of thermoelectric materials, by reducing the material dimensions, the existing thermoelectric materials can be made into nanotubes, which can greatly improve the ZT value of materials [7].…”

Electrodeposition of V-VI Nanowires and Their Thermoelectric Properties

“…Nanostructuration is one of the approaches to increase the figure of merit in thermoelectric materials (Dresselhaus et al, 2007; Martín-González et al, 2013; Ali et al, 2017; Chen et al, 2018; Goktas et al, 2018; Swinkels and Zardo, 2018; Selvan et al, 2019). In this sense, nanowires are a great field of study to underline the physics behind the influence of the nanostructuration on the improvement of the figure of merit (Domínguez-Adame et al, 2019). One of the parameters that is more influenced by nanostructuration is the lattice thermal conductivity.…”

“…One of the parameters that is more influenced by nanostructuration is the lattice thermal conductivity. This is due to the higher surface to volume ratio that these structures present (Domínguez-Adame et al, 2019). At the surface of the nanowires phonons are scattered, and this produces a reduction of the lattice thermal conductivity.…”