Flexible thermoelectric films formed using integrated nanocomposites with single-wall carbon nanotubes and Bi2Te3 nanoplates via solvothermal synthesis

Abstract

Single-wall carbon nanotubes (SWCNTs) and Bi2Te3 nanoplates are very promising thermoelectric materials for energy harvesting. When these two materials are combined, the resulting nanocomposites exhibit high thermoelectric performance and excellent flexibility. However, simple mixing of these materials is not effective in realizing high performance. Therefore, we fabricated integrated nanocomposites by adding SWCNTs during solvothermal synthesis for the crystallization of Bi2Te3 nanoplates and prepared flexible integrated nanocomposite films by drop-casting. The integrated nanocomposite films exhibited high electrical conductivity and an n-type Seebeck coefficient owing to the low contact resistance between the nanoplates and SWCNTs. The maximum power factor was 1.38 μW/(cm K2), which was 23 times higher than that of a simple nanocomposite film formed by mixing SWCNTs during drop-casting, but excluding solvothermal synthesis. Moreover, the integrated nanocomposite films maintained their thermoelectric properties through 500 bending cycles.

Photothermal Effects and Heat Conduction in Nanogranular Silicon Films

“…Drop casting, on the other hand, is a viable alternative bottom-up technique for the simple and inexpensive fabrication of thin nanogranular solid films with limited controllability, which has the potential to become a large-scale coating method. This technique is widely used to fabricate thermoelectrics [6] and hybrid polymer insulating films [7].…”

Highly Efficient Flexible n‐Type Thermoelectric Films Formed by Encapsulation of Bi2Se3‐MWCNT Hybrid Networks in Polyvinyl Alcohol

“…In this approach, the nanostructured inorganic materials such as bismuth chalcogenides are deposited directly on the CNT network. [11][12][13][14][15] For example, recently reported freestanding CNT-Bi 2 Te 3 hybrid networks showed a potential possibility to achieve power factor (PF) of ≈20 μW m −1 K −2 [15] and ZT ≈0.25 at room temperature. [12] However, in vast majority of reported n-type CNT-based freestanding networks, the pre-annealed in high-vacuum single-wall CNTs (SWCNT) were used as scaffold.…”

Evaluation of Thermoelectric Performance of Bi2Te3 Films as a Function of Temperature Increase Rate during Heat Treatment

“…Recently, there has been growing research on material flexibility for thermoelectric generators used for energy harvesting technology due to the applicability of flexible thermoelectric generators in various places [6][7][8][9][10], such as small areas and bent surfaces. For these conditions, thin film thermoelectric generators are highly suitable.…”