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Title: Improved electronic uniformity and nanoscale homogeneity in template-grown CsPbBr 3 nanorods
One-dimensional metal halide perovskites are among the most promising candidate materials for optoelectronic devices. However, the heterogeneity and fast degradation of perovskite nanowires (NWs) and nanorods (NRs) synthesized using conventional approaches impose a bottleneck for their optoelectronic applications. Recently, all-inorganic perovskite CsPbBr3 NRs with tailored dimensions, crafted using an amphiphilic bottlebrush-like block copolymer (BBCP) as nanoreactors, have demonstrated enhanced stabilities. Herein, we report the electronic investigation into these template-grown CsPbBr3 NRs using dielectric force microscopy (DFM), a contactless, nondestructive imaging technique. All freshly prepared CsPbBr3 NRs exhibited ambipolar behaviors for up to two months after sample synthesis. A transition from ambipolar to p-type behaviors occurred after two months, and nearly all NRs completed the transition within two weeks. Moreover, template-grown CsPbBr3 NRs displayed better nanoscale electronic homogeneity compared to their conventional counterparts. The improved electronic uniformity and nanoscale homogeneity place the template-grown CsPbBr3 NRs in a unique advantageous position for optoelectronic applications.  more » « less
Award ID(s):
1904042
PAR ID:
10543277
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Royal Society of Chemistry
Date Published:
Journal Name:
Nanoscale
Volume:
16
Issue:
19
ISSN:
2040-3364
Page Range / eLocation ID:
9455 to 9461
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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