MoS₂ nano flakes with self-adaptive contacts for efficient thermoelectric energy harvesting

Abstract

We examine the potential of the low-dimensional material MoS 2 for the efficient conversion of waste heat to electricity via the Seebeck effect. Recently monolayer MoS 2 nano flakes with self-adaptive Mo 6 S 6 contacts were formed, which take advantage of mechanical stability and chemical covalent bonding to the MoS 2 . Here, we study the thermoelectric properties of these junctions by calculating their conductance, thermopower and thermal conductance due to both electrons and phonons. We show that thermoelectric figures of merit ZT as high as ∼2.8 are accessible in these junctions, independent of the flake size and shape, provided the Fermi energy is close to a band edge. We show that Nb dopants as substituents for Mo atoms can be used to tune the Fermi energy, and despite the associated inhomogeneous broadening, room temperature values as high as ZT ∼ 0.6 are accessible, increasing to 0.8 at 500 K.

Enhanced thermoelectric performance of monolayer MoSSe, bilayer MoSSe and graphene/MoSSe heterogeneous nanoribbons

“…In the prior research, a relatively high in-plane Hall mobility (over 34000 cm 2 V -1 s -1 ) 6 , wide tunable range of Seebeck coefficient (-4×10 2 ~ -1×10 5 V K -1 ) 7 , and relatively low thermal conductivity (62.2 W m -1 K -1 ) 8 of monolayer MoS2 were demonstrated, which indicates transition metal dichalcogenides (TMDs) are particularly suited for thermoelectric applications [9][10][11][12] . In 2017, the first true Janus TMD was discovered-MoSSe, which was fabricated by fully replacing one S atoms with Se atoms within the monolayer MoS2 using the chemical vapour deposition (CVD) 13 .…”

Thermoelectric properties of oligoglycine molecular wires

“…24 Therefore, in recent years, different strategies have been proposed to exploit the thermoelectric properties of nanostructured organic materials or organic molecules. [25][26][27][28] Single-molecule devices provide a possible building block for constructing high-efficiency thermoelectric power generators. 29 However, to our knowledge, there are few reports about the thermoelectric properties of peptides.…”