Structure-correlated excitation wavelength-dependent optical properties of ZnO nanostructures for multifunctional applications

Abstract

Excitation wavelength-dependent visible emissions from ZnO nanostructures demonstrate that defect states are insufficient to explain their optical properties.

Tuning Visible-to-Near Infrared Dual-Band Emission in ZnO@β-SiC Composite Phosphor

“…Since the 740 nm emission is absent in both reference samples, it is most likely associated with the involvement of modified NBOHC in the Zn 2 SiO 4 phase at the ZnO/β-SiC interface as mentioned above. Moreover, a slight blueshift has been observed for the green emission in Z-12A with increasing excitation wavelength [see Figure a] which further supports the involvement of different optically active defect centers . To gain further insights into this, time-resolved PL (TR-PL) measurements have also been carried out as it is a powerful technique to follow the dynamics of charge carrier generation and recombination.…”

“…Moreover, a slight blueshift has been observed for the green emission in Z-12A with increasing excitation wavelength [see Figure 3a] which further supports the involvement of different optically active defect centers. 37 To gain further insights into this, time-resolved PL (TR-PL) measurements have also been carried out as it is a powerful technique to follow the dynamics of charge carrier generation and recombination. Prior to discussing TR-PL, it is important to check whether there is any correlation behind the interaction between ZnO and SiO 2 (as predicted above) on the 560 and 740 nm peaks in Figure 2.…”

Effect of particle size on optical and electrical properties of thin films – a simulation approach

“…There are endless reports of determination of optical properties of different materials developed through different physical deposition techniques in thin film form. For instances, in the year 2023 only:-Vijay et al investigated the impact of annealing temperature on the microstructure, defects, and optical properties of ZnO thin films using a sol-gel-based spin coating method and showed that particle size increases with annealing temperature, and the optical band gap reduces [22]; Banerjee et al investigated the origin of visible emissions in ZnO, focusing on excitation wavelength-dependent tuneable emission [23]; Orek et al studied the electrical, optical, and structural properties of a wurtzite-like zinc oxide nanostructure, examining the influence of quantum confinement on optical characteristics [24]; Sarmh and Borah studied nanocrystalline CdSe thin films, finding them suitable for optoelectronic devices with defect-controlled photocurrents and a doubly activated transport mechanism [25]; Gonçalves et al studied the nonlinear optical response of CdSe, revealing a predominant fifth-order nonlinear absorption behaviour and a nonlinear refractive index in good agreement with the OKG [26]; Kafashan et al investigated the impact of Cu-doping on Cadmium selenide (CdSe), highlighting its potential applications in optoelectronics due to improved absorbance, reflectance, and band gap [27].…”

Engineering of Multidimensional Core-Shell Perovskite Precursors to Obtain Superior Luminescence and Incorporating in Luminescent Solar Concentrators

“…PLQYs up to 25% and 23% are reported for organic-inorganic Cuand Zn-based metal halides with potential applications in fingerprint detection [35,36]. A study on different morphologies of ZnO nanostructures reveals that visible emission from these nanostructures originates from oxygen-related adsorbed species [37]. The ZnO nanostructure dimension is also varied by the hydroxide ion concentration of precur-sors, which affects the surface defect states and hence the QY [38].…”