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  • Large-area 2D PtTe 2 /silicon vertical-junction devices with ultrafast and high-sensitivity photodetection and photovoltaic enhancement by integrating water droplets
Title: Large-area 2D PtTe 2 /silicon vertical-junction devices with ultrafast and high-sensitivity photodetection and photovoltaic enhancement by integrating water droplets
2D PtTe 2 layers, a relatively new class of 2D crystals, have unique band structure and remarkably high electrical conductivity promising for emergent opto-electronics. This intrinsic superiority can be further leveraged toward practical device applications by merging them with mature 3D semiconductors, which has remained largely unexplored. Herein, we explored 2D/3D heterojunction devices by directly growing large-area (>cm 2 ) 2D PtTe 2 layers on Si wafers using a low-temperature CVD method and unveiled their superior opto-electrical characteristics. The devices exhibited excellent Schottky transport characteristics essential for high-performance photovoltaics and photodetection, i.e. , well-balanced combination of high photodetectivity (>10 13 Jones), small photo-responsiveness time (∼1 μs), high current rectification ratio (>10 5 ), and water super-hydrophobicity driven photovoltaic improvement (>300%). These performances were identified to be superior to those of previously explored 2D/3D or 2D layer-based devices with much smaller junction areas, and their underlying principles were confirmed by DFT calculations.  more » « less
Award ID(s):
1728309
NSF-PAR ID:
10274630
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Nanoscale
Volume:
12
Issue:
45
ISSN:
2040-3364
Page Range / eLocation ID:
23116 to 23124
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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