Synthesis of ZnO nanocrystals by subsequent implantation of Zn and O species

Abstract

We report the preparation of ZnO nanocrystals embedded in a SiO2 matrix formed using sequential zinc and oxygen ion implantations. The optical absorption spectra and photoemission spectra of zinc implanted and zinc/oxygen coimplanted silica show that the first zinc implantation produces zinc clusters and that the subsequent oxygen implantation following the zinc implantation rearranges the distribution of zinc and oxygen ions at an atomic level. While thermal annealing of Zn only implanted silica leads to the formation of Zn nanocrystals, thermal annealing of zinc/oxygen coimplanted silica promotes the growth of ZnO nanocrystals. The absorption and photoluminescence spectra show that ZnO nanocrystals form in an amorphous SiO2 matrix and that their systematic change as a function of annealing temperature corresponds to the typical correlation between the increase of particle size and a redshift in near-band-edge emission.

Low-temperature growth of ZnO with controllable shapes and band gaps

“…According to our previous report [19], the bilayer ZnO particles (made by our WPN system) have the unique particle surfaces modified by the absorbed PVP and defects such as edge dislocations around the interface between the two parallel plate units, which should lead to the presence of mechanical strains in the particles. Because the large size and pure hexagonal wurtzite structure of our samples exclude the effects of impurities and quantum confinement [22,23], the large variation in band position and width should mainly associate with mechanical strains and structural defects, which vary with the samples and are known to alter the band gap and the excitonic effect [10,19,24,25].…”

Composition/Structural Evolution and Optical Properties of ZnO/Zn Nanoparticles by Laser Ablation in Liquid Media

“…Although there are very few reports on the zinc surface plasmon reasonance (SPR), recently, Lee and co-workers have reported the zinc SPR absorption in 255 nm of Zn nanocrystals embedded in a SiO 2 matrix. 50 We suggest that the peak at 242 nm comes from the SPR absorption of zinc nanoparticles in the SDS aqueous solution. In fact, there are several metals whose SPR is located in the range of 200-300 nm, such as In, Mg, Cr, Pd, Cd, and so forth.…”

Low-temperature synthesis and characterization of ZnO quantum dots

“…The special application advantages of ZnO QDs and NPs in the area of bioscience also improve more attention due to its "survival lifetime" of a few hours, the slow solubility and high compatibility in biofluid and necessaries of Zn for human beings everyday [11]. Therefore, a number of reports of fabrication, structural, and optical characterization of ZnO QDs have been done in recent years [12][13][14][15][16][17][18].…”

“…So far, various physical or chemical synthetic approaches have been developed to fabricate QDs, such as vapor phase transport process [12], metal-organic chemical-vapor deposition (MOCVD) [13,14], RF magnetron sputtering [15], ion implantation [16], precipitation [17] and flame spray pyrolysis [18]. According to these methods, the complex processes, sophisticated equipment and economically prohibitive high temperatures are usually required, which decides they are not suitable for large-scale fabrication with a relatively low cost.…”