Significantly Enhanced Thermoelectric Performance of γ-In2Se3 through Lithiation via Chemical Diffusion
Year: 2017
Type: article
Abstract: γ-In 2 Se 3 is selected as a thermoelectric candidate because it has a unique crystal structure and thermal stability at relatively high temperatures. In this work, we have prepared lithiated γ-In 2 Se 3 through chemical diffusion and investigated its band structures and thermoelectric performance. After lithiation of γ-In 2 Se 3 in a lithium acetate (CH 3 COOLi) solution at 50 °C for 30 h, we have observed a high Hall carrier concentration ( n H ) of ≤1.71 × 10 18 cm –3 at room temperature, which is ∼4 orders of magnitude higher than that of pristine γ-In 2 Se 3 . The enhancement of n H is directly responsible for the remarkable improvement in electrical conductivity and can be elucidated as the Fermi level ( F r ) unpinning and moving toward the conduction band through the dominant interstitial occupation of Li + in the γ-In 2 Se 3 lattice. Combined with the minimum lattice thermal conductivity (κ L = 0.30–0.34 W K –1 m –1 ) at ∼923 K, the highest ZT value of 0.62–0.67 is attained, which is approximately 9–10 times that of pristine γ-In 2 Se 3, proving that the lithiation in γ-In 2 Se 3 is an effective approach to the improvement in thermoelectric performance.
Source: Chemistry of Materials
Authors: Jiaolin Cui, Hua Peng, Zhiliang Song, Zhengliang Du, Yimin Chao, Gang Chen
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2742988044