Influence of metal organic chemical vapour deposition growth conditions on vibrational and luminescent properties of ZnO nanorods

Abstract

A detailed optical characterization by means of micro Raman and cathodoluminescence spectroscopy of catalyst-free ZnO nanorods grown by atmospheric-metal organic chemical vapour deposition has been carried out. This characterization has allowed correlating the growth conditions, in particular the precursors partial-pressures and growth time, with the optical properties of nanorods. It has been shown that a high Zn supersaturation can favor the incorporation of nonradiative recombination centers, which can tentatively be associated with Zn I -related defects. Characterization of individual nanorods has evidenced that Zn I -related defects have a tendency to accumulate in the tip part of the nanorods, which present dark cathodoluminescence contrast with respect to the nanorods bottom. The effect of a ZnO buffer layer on the properties of the nanorods has been also investigated, showing that the buffer layer improves the luminescence efficiency of the ZnO nanorods, revealing a significant reduction of the concentration of nonradiative recombination centers. V C 2013 AIP Publishing LLC [http://dx.

Optical and Structural Characteristics of Rare Earth-Doped ZnO Nanocrystals Prepared in Colloidal Solution

“…In the PL spectra of the ZnO NCs, a narrow near-band edge emission (NBE) around 380 nm and a broad band deep-level emission (DLE) between 450 nm to 700 nm were generally observed [5][6][7][8]27]. Figure 3 shows the spectra normalized to the absorbance at λex = 290 nm.…”

“…The stronger suppression of the NBE band compared to the DLE band most likely indicated that RE ions acted as non-radiative defects, the origin of which was different from the radiative defects responsible for the DLE band. In the PL spectra of the ZnO NCs, a narrow near-band edge emission (NBE) around 380 nm and a broad band deep-level emission (DLE) between 450 nm to 700 nm were generally observed [5][6][7][8]27]. Figure 3 shows the spectra normalized to the absorbance at λ ex = 290 nm.…”

“…Due to the size effects, ZnO nanostructures offer exciton-related ultra-violet (UV)/blue light emission at room temperature [5]. In addition, the presence of deep centers stemming from intrinsic and/or extrinsic defects allows ZnO nanostructures to emit light in the violet-red spectral range, covering almost the entire visible spectral range [6]. Despite the Photochem 2022, 2 516 progress in the preparation of nanostructured ZnO materials with high crystalline quality and well-defined size, the influence of synthesis/postprocessing parameters on their optical, electronic, and other properties is not fully understood and still attracts attention.…”

STUDY THE OPTICAL PROPERTIES OF THE VARIOUS DEPOSITION SOLUTIONS OF ZnO NANORODS GROWN ON GLASS SUBSTRATE USING CHEMICAL BATH DEPOSITION TECHNIQUE

“…There are many synthesized techniques that have been introduced for the growth of a set of ZnO nanorods on the large domain of substrates [15]. These techniques contain radiofrequency magnetron sputtering [16], metallic organic chemical vapor deposition (MOCVD) [17], chemical vapor deposition (CVD) [18], pulsed laser deposition [19], vapor phase transport [20], spray pyrolysis [21] and electrochemical deposition [22]. During these techniques mention above, the chemical bath deposition (CBD) method is a low-temperature technique, and possibly the lowest cost method for growing ZnO nanorods not need the high production yield [23].…”

Influence of Codoping on the Optical Properties of ZnO Thin Films Synthesized on Glass Substrate by Chemical Bath Deposition Method

“…Due to its unique optical, semiconductor, and optical properties, ZnO thin films have been extensively studied for various applications. Several methods such as chemical bath deposition, MOCVD, melt growth, ion implementation, DC reactive magnetron cosputtering, and hydrothermal and simple chemical pyrolysis have been used to synthesize ZnO thin films [7][8][9][10][11][12][13]. Of late, ZnO thin films are being fabricated by codoping for enhancing the efficiency of ZnO film in optoelectronic devices.…”