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Title: Chemically tuned intermediate band states in atomically thin Cu x GeSe/SnS quantum material for photovoltaic applications
A new generation of quantum material derived from intercalating zerovalent atoms such as Cu into the intrinsic van der Waals gap at the interface of atomically thin two-dimensional GeSe/SnS heterostructure is designed, and their optoelectronic features are explored for next-generation photovoltaic applications. Advanced ab initio modeling reveals that many-body effects induce intermediate band (IB) states, with subband gaps (~0.78 and 1.26 electron volts) ideal for next-generation solar devices, which promise efficiency greater than the Shockley-Queisser limit of ~32%. The charge carriers across the heterojunction are both energetically and spontaneously spatially confined, reducing nonradiative recombination and boosting quantum efficiency. Using this IB material in a solar cell prototype enhances absorption and carrier generation in the near-infrared to visible light range. Tuning the active layer’s thickness increases optical activity at wavelengths greater than 600 nm, achieving ~190% external quantum efficiency over a broad solar wavelength range, underscoring its potential in advanced photovoltaic technology.  more » « less
Award ID(s):
2202101
PAR ID:
10501540
Author(s) / Creator(s):
;
Publisher / Repository:
AAAS
Date Published:
Journal Name:
Science Advances
Volume:
10
Issue:
15
ISSN:
2375-2548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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