Deformable thermoelectric sponge based on layer-by-layer self-assembled transition metal dichalcogenide nanosheets for powering electronic skin

• Published in: Ceramics international Vol. 49; no. 6; pp. 9307 - 9315
• Main Authors: Nghia, Dang Xuan, Baek, Jong Jin, Oh, Jin Young, Lee, Tae Il
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.03.2023
• Subjects: Deformable thermoelectric sponge; Electronic skin (e-skin); Layer-by-layer self-assembly; Thermoelectric generator; Transition metal dichalcogenide nanosheets; Thermoelectric generator; Electronic skin (e-skin); Transition metal dichalcogenide nanosheets; Deformable thermoelectric sponge; Layer-by-layer self-assembly
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2022.11.097

In this study, we fabricated mechanically deformable thermoelectric sponges comprising transition metal dichalcogenides (TMDs) and polyethyleneimine (PEI) through a layer-by-layer (LBL) self-assembly technique for a thermoelectric power supply for electronic skin. Chemically exfoliated molybdenum sulfide (MoS2) and niobium diselenide (NbSe2) were prepared as p- and n-type room-temperature thermoelectric materials, respectively, and deposited on a melamine sponge via electrostatic bonding with PEI to obtain stable mechanical stretchability and low thermal conductivity. Five bilayers of LBL self-assembled thermoelectric sponges exhibited an enhanced thermoelectric performance and figure of merit, which resulted from the improvement in the Seebeck coefficient compared with that of pristine chemically exfoliated TMDs owing to the energy filtering effect and the extremely low thermal conductivity owing to the phonon scattering effect at several created interfaces and the porous structure of the sponge. Additionally, the thermoelectric sponges showed mechanical stability during operation under stretching and compression and mechanical durability over 10,000 cycles under 30% tensile strain. Finally, based on the proposed thermoelectric sponge, a power patch that can be installed on the back of a hand to produce electrical energy in real time was successfully demonstrated.