Phase-dependent microstructure modification leads to high thermoelectric performance in n-type layered SnSe2 - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Acta Materialia Année : 2024

Phase-dependent microstructure modification leads to high thermoelectric performance in n-type layered SnSe2

Résumé

Microstructure control is crucial for thermoelectrics since it is intimately related to the scattering mechanism of both electrons and phonons. Herein, we propose a new strategy to modify microstructure by phase regulation that simultaneously induces high carrier mobility and low lattice thermal conductivity. As demonstrated in layered SnSe2, the addition of Cu can induce a phase transition from space group P3¯m1 to P63mc. Due to the enlarged formation energy of stacking faults in the later phase, the stacking fault density is greatly reduced after heat treatment that leads to an increased grain size. Accordingly, the carrier mobility of SnSe1.97Br0.03–3 % Cu sample is enhanced by 100 % at room temperature. Furthermore, the reduction of stacking fault density is accompanied by the formation of pores in the matrix, which results in low lattice thermal conductivity. As a result, a record peak zT of 1.13 for SnSe2-based materials is achieved at 773 K, and the attained ZTave of 0.62 is a record-high value among n-type polycrystalline layered materials working in intermediate-to-high temperature region. This work provides a feasible strategy to decouple the electron and phonon transport in layered thermoelectric compounds by phase-dependent microstructure modification. © 2023

Domaines

Matériaux
Fichier sous embargo
Fichier sous embargo
0 0 7
Année Mois Jours
Avant la publication
mardi 7 mai 2024
Fichier sous embargo
mardi 7 mai 2024
Connectez-vous pour demander l'accès au fichier

Dates et versions

hal-04337962 , version 1 (08-04-2024)

Licence

Paternité - Pas d'utilisation commerciale - Pas de modification

Identifiants

Citer

Yiqing Wei, Jingwei Li, Daliang Zhang, Bin Zhang, Zizhen Zhou, et al.. Phase-dependent microstructure modification leads to high thermoelectric performance in n-type layered SnSe2. Acta Materialia, 2024, Acta Materialia, 263, pp.119504. ⟨10.1016/j.actamat.2023.119504⟩. ⟨hal-04337962⟩
22 Consultations
1 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More