The thermoelectric properties of Au nanoparticle-incorporated Al-doped mesoporous ZnO thin films.

Min-Hee Hong,Hyung-Ho Park,Wooje Han,Kyu-Yeon Lee

doi:10.1098/rsos.181799

Abstract

Mesoporous Al-doped ZnO thin films incorporated with gold nanoparticles (Au NPs) were synthesized using a sol–gel and evaporation-induced self-assembly process. In this study, the complementary effects of Au NP incorporation and Al doping on the thermoelectric properties of mesoporous ZnO thin films were analysed. The incorporated Au NPs induced an increase in electrical conductivity but a detriment in the pore arrangement of the mesoporous ZnO thin film, which was accompanied by a decrease in porosity. However, the addition of the Al dopant minimized the pore structural collapse because of the inhibition of the grain growth in the ZnO skeletal structure, resulting in the enhancement of the pore arrangement and porosity. When the Au NPs and Al dopant were added at the same time, the degradation in the pore structure was minimized and the electrical conductivity was effectively increased, but the absolute value of the Seebeck coefficient was decreased. However, as a result, the thermoelectric power factor was increased by 2.4 times compared to that of the pristine mesoporous ZnO thin film. It was found that co-introducing the Au NPs and Al doping to the mesoporous ZnO structure was effective in preserving the pore structure and increasing the electric conductivity, thereby enhancing the thermoelectric property of the mesoporous ZnO thin film.

Highlights

Nowadays, fossil fuels continue to be rapidly depleted, and so the development of alternative energy sources has become very important and the interest in energy conversion techniques is rapidly increasing
It was found that co-introducing the Au NPs and Al doping to the mesoporous Zinc oxide (ZnO) structure was effective in preserving the pore structure and increasing the electric conductivity, thereby enhancing the thermoelectric property of the mesoporous ZnO thin film
An Au NP-incorporated, Al-doped mesoporous ZnO thin film was synthesized using a sol – gel and evaporation-induced self-assembly (EISA) process, and the change in the thermoelectric property of the resulting thin film based on crystallinity, pore structure, the Seebeck coefficient and electrical conductivity was investigated

Summary

Introduction

Fossil fuels continue to be rapidly depleted, and so the development of alternative energy sources has become very important and the interest in energy conversion techniques is rapidly increasing. Thermoelectricity has been actively studied, because this technique comprises a green energy conversion 2 system in which electric current is generated from materials with a temperature gradient. The thermoelectric property can be represented by the figure of merit, royalsocietypublishing.org/journal/rsos R. S2sT k where S, s, k and T are the Seebeck coefficient, electrical conductivity, thermal conductivity and temperature, respectively. To enhance the thermoelectric property, a high Seebeck coefficient value, electrical conductivity and low thermal conductivity are essential

Methods

Results

Conclusion