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Title: Surface Modification of Black Phosphorus with Group 13 Lewis Acids for Ambient Protection and Electronic Tuning
Abstract

Herein we introduce a facile, solution‐phase protocol to modify the Lewis basic surface of few‐layer black phosphorus (bP) and demonstrate its effectiveness at providing ambient stability and tuning of electronic properties. Commercially available group 13 Lewis acids that range in electrophilicity, steric bulk, and Pearson hard/soft‐ness are evaluated. The nature of the interaction between the Lewis acids and thebP lattice is investigated using a range of microscopic (optical, atomic force, scanning electron) and spectroscopic (energy dispersive, X‐ray photoelectron) methods. Al and Ga halides are most effective at preventing ambient degradation ofbP (>84 h for AlBr3), and the resulting field‐effect transistors show excellentIVcharacteristics, photocurrent, and current stability, and are significantly p‐doped. This protocol, chemically matched tobP and compatible with device fabrication, opens a path for deterministic and persistent tuning of the electronic properties inbP.

 
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Award ID(s):
1807394 1719797
NSF-PAR ID:
10220731
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
60
Issue:
15
ISSN:
1433-7851
Format(s):
Medium: X Size: p. 8329-8336
Size(s):
["p. 8329-8336"]
Sponsoring Org:
National Science Foundation
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