TY - JOUR
T1 - Phase-Defined van der Waals Schottky Junctions with Significantly Enhanced Thermoelectric Properties
AU - Wang, Qiaoming
AU - Yang, Liangliang
AU - Zhou, Shengwen
AU - Ye, Xianjun
AU - Wang, Zhe
AU - Zhu, Wenguang
AU - McCluskey, Matthew D.
AU - Gu, Yi
N1 - Funding Information:
This work was supported by the U.S. National Science Foundation under grants DMR-1506480 (Y.G.) and DMR-1561419 (M.D.M.). Z.W. and W.Z. acknowledge support from the National Natural Science Foundation of China (grant nos. 11374273, 11674299, 11634011) and the Fundamental Research Funds for the Central Universities (grant no. WK2340000063). We thank Prof. Brian Collins group for the assistance in the photocurrent spectroscopy measurements.
Publisher Copyright:
© 2017 American Chemical Society.
PY - 2017/7/6
Y1 - 2017/7/6
N2 - We demonstrate a van der Waals Schottky junction defined by crystalline phases of multilayer In2Se3. Besides ideal diode behaviors and the gate-tunable current rectification, the thermoelectric power is significantly enhanced in these junctions by more than three orders of magnitude compared with single-phase multilayer In2Se3, with the thermoelectric figure-of-merit approaching ∼1 at room temperature. Our results suggest that these significantly improved thermoelectric properties are not due to the 2D quantum confinement effects but instead are a consequence of the Schottky barrier at the junction interface, which leads to hot carrier transport and shifts the balance between thermally and field-driven currents. This "bulk" effect extends the advantages of van der Waals materials beyond the few-layer limit. Adopting such an approach of using energy barriers between van der Waals materials, where the interface states are minimal, is expected to enhance the thermoelectric performance in other 2D materials as well.
AB - We demonstrate a van der Waals Schottky junction defined by crystalline phases of multilayer In2Se3. Besides ideal diode behaviors and the gate-tunable current rectification, the thermoelectric power is significantly enhanced in these junctions by more than three orders of magnitude compared with single-phase multilayer In2Se3, with the thermoelectric figure-of-merit approaching ∼1 at room temperature. Our results suggest that these significantly improved thermoelectric properties are not due to the 2D quantum confinement effects but instead are a consequence of the Schottky barrier at the junction interface, which leads to hot carrier transport and shifts the balance between thermally and field-driven currents. This "bulk" effect extends the advantages of van der Waals materials beyond the few-layer limit. Adopting such an approach of using energy barriers between van der Waals materials, where the interface states are minimal, is expected to enhance the thermoelectric performance in other 2D materials as well.
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U2 - 10.1021/acs.jpclett.7b01089
DO - 10.1021/acs.jpclett.7b01089
M3 - Article
C2 - 28593766
AN - SCOPUS:85022096747
SN - 1948-7185
VL - 8
SP - 2887
EP - 2894
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
IS - 13
ER -