TY - JOUR
T1 - Intercalation
T2 - Building a natural superlattice for better thermoelectric performance in layered chalcogenides
AU - Wan, Chunlei
AU - Wang, Yifeng
AU - Wang, Ning
AU - Norimatsu, Wataru
AU - Kusunoki, Michiko
AU - Koumoto, Kunihito
PY - 2011/5
Y1 - 2011/5
N2 - A natural superlattice with composition (SnS) 1.2(TiS 2) 2, built by intercalating a SnS layer into the van der Waals gap of layered TiS 2, has been directly observed by high-resolution transmission electron microscopy (HRTEM). The thermoelectric performance is improved in the direction parallel to the layers because the electron mobility is maintained while simultaneously suppressing phonon transport, which is attributed to softening of the transverse sound velocities due to weakened interlayer bonding. In the direction perpendicular to the layers, the lattice thermal conductivity of (SnS) 1.2(TiS 2) 2 is even lower than the predicted minimum thermal conductivity, which may be caused by phonon localization due to the translational disorder of the SnS layers parallel to the layers. Moreover, we propose a large family of misfit-layer compounds (MX) 1+x (TX 2) n (M = Pb, Bi, Sn, Sb, rare-earth elements; T = Ti, V, Cr, Nb, Ta; X = S, Se; n = 1, 2, 3) with a natural superlattice structure as possible candidate high-performance thermoelectric materials.
AB - A natural superlattice with composition (SnS) 1.2(TiS 2) 2, built by intercalating a SnS layer into the van der Waals gap of layered TiS 2, has been directly observed by high-resolution transmission electron microscopy (HRTEM). The thermoelectric performance is improved in the direction parallel to the layers because the electron mobility is maintained while simultaneously suppressing phonon transport, which is attributed to softening of the transverse sound velocities due to weakened interlayer bonding. In the direction perpendicular to the layers, the lattice thermal conductivity of (SnS) 1.2(TiS 2) 2 is even lower than the predicted minimum thermal conductivity, which may be caused by phonon localization due to the translational disorder of the SnS layers parallel to the layers. Moreover, we propose a large family of misfit-layer compounds (MX) 1+x (TX 2) n (M = Pb, Bi, Sn, Sb, rare-earth elements; T = Ti, V, Cr, Nb, Ta; X = S, Se; n = 1, 2, 3) with a natural superlattice structure as possible candidate high-performance thermoelectric materials.
KW - Natural superlattice
KW - misfit-layer compounds
KW - thermal conductivity
KW - thermoelectric
UR - http://www.scopus.com/inward/record.url?scp=79955922446&partnerID=8YFLogxK
U2 - 10.1007/s11664-011-1565-5
DO - 10.1007/s11664-011-1565-5
M3 - 文章
AN - SCOPUS:79955922446
SN - 0361-5235
VL - 40
SP - 1271
EP - 1280
JO - Journal of Electronic Materials
JF - Journal of Electronic Materials
IS - 5
ER -