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Title: Controllable Nonclassical Conductance Switching in Nanoscale Phase‐Separated (PbI 2 ) 1− x (BiI 3 ) x Layered Crystals
Abstract

Layered 2D (PbI2)1−x(BiI3)xmaterials exhibit a nonlinear dependence in structural and charge transport properties unanticipated from the combination of PbI2and BiI3. Within (PbI2)1−x(BiI3)xcrystals, phase integration yields deceptive structural features, while phase boundary separation leads to new conductance switching behavior observed as large peaks in current during current–voltage (IV) measurements (±100 V). Temperature‐ and time‐dependent electrical measurements demonstrate that the behavior is attributed to ionic transport perpendicular to the layers. High‐resolution transmission electron microscopy reveals that the structure of (PbI2)1−x(BiI3)xis a “brick wall” consisting of two phases, Pb‐rich and Bi‐rich. These brick‐like features are 10s nm a side and it is posited that iodide ion transport at the interfaces of these regions is responsible for the conductance switching action.

 
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NSF-PAR ID:
10367387
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials
Volume:
33
Issue:
51
ISSN:
0935-9648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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