Enhanced Thermoelectric Characteristics of Ag2Se Nanoparticle Thin Films by Embedding Silicon Nanowires

Seunggen Yang,Sangsig Kim,Kyoungah Cho

doi:10.3390/en13123072

Abstract

A solution-processable Ag2Se nanoparticle thin film (NPTF) is a prospective thermoelectric material for plastic-based thermoelectric generators, but its low electrical conductivity hinders the fabrication of high performance plastic-based thermoelectric generators. In this study, we design Ag2Se NPTFs embedded with silicon nanowires (SiNWs) to improve their thermoelectric characteristics. The Seebeck coefficients are −233 and −240 µV/K, respectively, for a Ag2Se NPTF alone and a Ag2Se NPTF embedded with SiNWs. For the Ag2Se NPTF embedded with SiNWs, the electrical conductivity is improved from 0.15 to 18.5 S/m with the embedment of SiNWs. The thermal conductivities are determined by a lateral thermal conductivity measurement for nanomaterials and the thermal conductivities are 0.62 and 0.84 W/(m·K) for a Ag2Se NPTF alone and a Ag2Se NPTF embedded with SiNWs, respectively. Due to the significant increase in the electrical conductivity and the insignificant increase in its thermal conductivity, the output power of the Ag2Se NPTF embedded with SiNWs is 120 times greater than that of the Ag2Se NPTF alone. Our results demonstrate that the Ag2Se NPTF embedded with SiNWs is a prospective thermoelectric material for high performance plastic-based thermoelectric generators.

Highlights

Thermoelectric generators for energy conversion from ambient heat to electricity have been widely developed in the area of renewable energy [1,2]
As one way to make nanosized semiconductor materials, solution processes have been regarded as an attractive approach for the fabrication of next-generation flexible electronics since they have the potential advantages of low synthetic temperatures, large area processes, low cost and compatibilities with plastic substrates [4,5,6]
We evaluated the suitability of the Ag2 Se nanoparticle thin film (NPTF) embedded with silicon nanowires (SiNWs) as a thermoelectric material by comparing it with the Ag2 Se NPTF alone

Summary

Introduction

Thermoelectric generators for energy conversion from ambient heat to electricity have been widely developed in the area of renewable energy [1,2]. Nanosized semiconductor materials are suitable for thermoelectric materials because of their independent control of electrical and thermal conductivities [1,2,3]. As one way to make nanosized semiconductor materials, solution processes have been regarded as an attractive approach for the fabrication of next-generation flexible electronics since they have the potential advantages of low synthetic temperatures, large area processes, low cost and compatibilities with plastic substrates [4,5,6]. Among nanosized semiconductor materials, solution-processable semiconductor nanoparticles (NPs), such as mercury chalcogenide [4] and silver chalcogenide [5] NPs, have emerged as thermoelectric materials for plastic-based thermoelectric generators [6] because they are processed at sufficiently low temperatures compared to the thermal degradation temperature of plastic substrates. Silver selenide (Ag2 Se) NPs have been studied as a promising thermoelectric

Methods

Results

Conclusion