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Title: CsPbBr3 and Cs2AgBiBr6 Composite Thick Films with Potential Photodetector Applications
This paper investigates the optoelectronic properties of CsPbBr3, a lead-based perovskite, and Cs2AgBiBr6, a lead-free double perovskite, in composite thick films synthesized using mechanochemical and hot press methods, with poly(butyl methacrylate) as the matrix. Comprehensive characterization was conducted, including X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), UV–visible spectroscopy (UV–Vis), and photoluminescence (PL). Results indicate that the polymer matrix does not significantly impact the crystalline structure of the perovskites but has a direct impact on the grain size and surface area, enhancing the interfacial charge transfer of the composites. Optical characterization indicates minimal changes in bandgap energies across all different phases, with CsPbBr3 exhibiting higher photocurrent than Cs2AgBiBr6. This is attributed to the CsPbBr3 superior charge carrier mobility. Both composites showed photoconductive behavior, with Cs2AgBiBr6 also demonstrating higher-energy (X-ray) photon detection. These findings highlight the potential of both materials for advanced photodetector applications, with Cs2AgBiBr6 offering an environmentally Pb-free alternative.  more » « less
Award ID(s):
2044675
PAR ID:
10568144
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
https://www.mdpi.com/1996-1944/17/20/5123
Date Published:
Journal Name:
Materials
Volume:
17
Issue:
20
ISSN:
1996-1944
Page Range / eLocation ID:
5123
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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