Enhanced Transverse Seebeck Coefficients in 2D/2D PtSe₂/MoS₂ Heterostructures Using Wet-Transfer Stacking

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Estimating thermoelectric (TE) properties of 2D transition metal dichalcogenide (TMDC) materials is challenging due to high electrical resistance.
• Accurate measurement of the Seebeck coefficient is crucial for TE device applications.

Purpose of the Study:

• To develop an innovative method for measuring large transverse Seebeck coefficients in 2D TMDC materials.
• To investigate the TE properties of a novel heterostructure composed of low-resistance (LR) PtSe2 and high-resistance (HR) MoS2.

Main Methods:

• Fabrication of a 2D/2D heterostructure using wet-transfer stacking of LR-PtSe2 (3 nm) on HR-MoS2 (>10 MΩ).
• Measurement of the transverse Seebeck coefficient of the stacked heterostructure film.

Main Results:

• The LR-PtSe2/HR-MoS2 heterostructure exhibited a high Seebeck coefficient exceeding 190 μV/K with a temperature difference as low as 5 K.
• An additional interfacial Seebeck effect was identified as the cause for the enhanced performance.

Conclusions:

• The proposed LR-2D/HR-2D heterostructure enables accurate measurement of large Seebeck coefficients in 2D materials.
• This approach offers promising potential for developing innovative TE devices based on 2D/2D heterostructures.