Progress on Material Design and Device Fabrication via Coupling Photothermal Effect with Thermoelectric Effect

Abstract

Recovery and utilization of low-grade thermal energy is a topic of universal importance in today's society. Photothermal conversion materials can convert light energy into heat energy, which can now be used in cancer treatment, seawater purification, etc., while thermoelectric materials can convert heat energy into electricity, which can now be used in flexible electronics, localized cooling, and sensors. Photothermoelectrics based on the photothermal effect and the Seebeck effect provide suitable solutions for the development of clean energy and energy harvesting. The aim of this paper is to provide an overview of recent developments in photothermal, thermoelectric, and, most importantly, photothermal-thermoelectric coupling materials. First, the research progress and applications of photothermal and thermoelectric materials are introduced, respectively. After that, the classification of different application areas of materials coupling photothermal effect with thermoelectric effect, such as sensors, thermoelectric batteries, wearable devices, and multi-effect devices, is reviewed. Meanwhile, the potential applications and challenges to be overcome for future development are presented, which are of great reference value in waste heat recovery as well as solar energy resource utilization and are of great significance for the sustainable development of society. Finally, the challenges of photothermoelectric materials as well as their future development are summarized.

Keywords: photothermal effect; photothermoelectric effect; polymer composites; thermoelectric effect.

Figure 1

Schematic illustration of materials, mechanisms, and applications of the PTE composites.

Figure 2

Power generation mechanism of two TE materials. (a) n-type and (b) p-type e-TE materials based on the Seebeck effect. i-TEs based on (c) the thermogalvanic effect and (d) the thermodiffusion effect [59] (Copyright from Elsevier).

Figure 3

Schematic illustration of the preparation procedure of the PPy/a-SWCNT composites [79] (Copyright from Elsevier).

Figure 4

(a) Schematic of the formation of the PAAm/LiTFSI-Fe(CN)₆^3−/4− hydrogel electrolyte. (b) Schematic showing the working principle of the TEC based on the hydrogel electrolyte [90] (Copyright from the Royal Society of Chemistry).

Figure 5

Schematic illustrating the construction of the PTEH-Interlocking and their potential application for photothermoelectric energy conversion [102].

Figure 6

Simple three-layer structure of the developed hybrid photothermoelectric generator (PTEG) illustrated by a schematic diagram and photographic images. (a) The developed PTEG is composed of a flexible substrate made of polyimide film (PI), a thermocouple chain made of n-type thermoelectric material (i.e., Bi₂Te_2.7Se_0.3) and p-type thermoelectric material (i.e., Sb₂Te₃) to scavenge thermal energy, and a light-to-thermal conversion layer composed of a light-absorbing film and a light-reflecting film to scavenge radiation energy. (b) Photograph of the fabricated thermoelectric generator with dimensions of 75 mm × 40 mm × 0.2 mm (eight pairs of thermocouples). (c) Photograph of the fabricated PTEG with dimensions of 75 mm × 40 mm × 1 mm after preparing the light-to-thermal conversion layer. These two photographic images demonstrated the good flexibility of the hybrid energy harvester due to its simple three-layer structure and flexible materials [104] (Copyright from the American Chemical Society).