Morphological, structural, optical and dielectric analysis of Cs₂TiBr₆ perovskite nanoparticles

Abstract

In the pursuit of lead-free perovskite materials suitable for harnessing solar energy, a recent discovery has emerged regarding Cs2TiBr6.

Understanding charge transport and dielectric relaxation properties in lead-free Cs2ZrCl6 nanoparticles

“… 29 The decreasing nature of the semi-circle radii with increasing temperature in the Cole–Cole plot again confirms the NTCR behavior of the material. 7 This also indicates that the conduction process is thermally activated, and the material exhibits semiconductor characteristics. Impedance spectra at all temperatures are fitted using ZView software, and the desired circuit model is obtained in this case by connecting two parallel RC elements in series.…”

“…Specifically, Cs 2 ZrCl 6 exhibits a higher dielectric constant when juxtaposed with compounds such as Cs 2 TiBr 6 , Cs 2 MSbBr 6 (where M = Cu, Ag), and Cs 2 MBiCl 6 (where M = Cu, Ag). 7,8,38 Conversely, it showcases a lower dielectric loss when contrasted with compounds like CsPbBr 3 , CsPbI 3 , and CsCuCl 3 . 16,39,40…”

“…The width of the peak indicates a significant deviation from an ideal Debye-type nature. 7 The movement of long-range charge carriers is primarily responsible for transport below the peak loss frequency, and it is contributed to by the motion of localized carriers above the relaxation frequency. The shift of the relaxation peak towards a high-frequency regime with temperature indicates a thermally dependent relaxation mechanism.…”

“…6(a) ) can be explained by Maxwell–Wagner interfacial polarization, in accordance with Koop's phenomenological theory. 7 In Cs 2 ZrCl 6 , molecules with permanent dipolar moments can change their orientation along the direction of the electric field in the low-frequency region. Thus, in this region, dipoles easily follow the quasi-static field, causing an increase in the dielectric constant ε ′( ω ).…”

“…Consequently, challenges remain regarding the end-of-life management and recyclability of these alternatives. 7,8…”