Controlled Precipitation of Zinc Oxide Particles at Room Temperature

Oliveira, Ana Paula Almeida de; Hochepied, Jean-François; Grillon, F.; Berger, Marie‐Hélène

doi:10.1021/cm0213725

Cited by 185 publications

(147 citation statements)

References 27 publications

Supporting

Mentioning

134

Contrasting

Unclassified

Order By: Relevance

“…The removal of catalyst from the particle surface was demonstrated by Raman spectra of the particles before and after the washing procedure with distilled water. The n(SO) and n(SO 3 2 ) stretching bands, appearing at 1125 and 1037 cm 21 , respectively, 34 disappear after the washing procedure. This result also indicates that insoluble zinc tosylate was not formed.…”

Section: Results and Discussion I Morphological And Structural Charamentioning

confidence: 96%

Precipitation of monodisperse ZnO nanocrystals via acid-catalyzed esterification of zinc acetate

et al. 2006

View full text Add to dashboard Cite

A wet-chemical method to produce zinc oxide nanocrystals of monodisperse size distribution (diameter range of 20-80 nm) is presented. The synthesis starts from zinc acetate dihydrate which is converted to ZnO in the presence of 1-pentanol in m-xylene at 130 uC. We report for the first time catalysis of this reaction by p-toluene sulfonic acid monohydrate (p-TSA), which allows a shorter reaction time and improves both the reproducibility of the particle size distribution and the crystallinity of the particles. The reaction can be scaled up to give multigram quantities of product per batch. Particles were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), and photoluminesence (PL) spectroscopy. Room temperature PL spectra of ZnO prepared without catalyst exhibit a strong and sharp UV emission band at ca. 385 nm and a weak and very broad green-yellow visible emission centered at ca. 550-560 nm. However, for nanoparticles precipitated in the presence of p-TSA, the UV emission is enhanced by a factor of 4, which can be correlated with the improvement of crystal perfection. A particle formation mechanism is discussed.

show abstract

Section: Results and Discussion I Morphological And Structural Charamentioning

confidence: 96%

Precipitation of monodisperse ZnO nanocrystals via acid-catalyzed esterification of zinc acetate

et al. 2006

View full text Add to dashboard Cite

show abstract

“…On the other hand, doping of ZnO in HCl resulted in absorption bands at 337 and 386 nm and a broad band between 410 and 1000 nm because of the dopant effect. 27,28 Next, the UV-Vis spectra of ZnO-PANI exhibited bands at 330 and 620 nm because of the pÀp* and nÀp* transitions, respectively. On protonation, the band observed at 330 nm in the UV-Vis spectra of ZnO-PANI shifted to 370 nm (Figure 2d).…”

Section: Optical Characterizationsmentioning

confidence: 99%

Evaluating the chemio-physio properties of novel zinc oxide–polyaniline nanocomposite polymer films

Alvi

Ram

Gómez

et al. 2010

Polym J

View full text Add to dashboard Cite

Recently, polymer matrix-based nanocomposites have become a prominent area of research and development in optics, as well as in optoelectronic, biomedical, electrical and electronic applications. Organic polymer-based electronic devices have the potential to be lower in cost and more flexible in the manner in which they are manufactured. However, they need significant improvement in both efficiency and long-term stability. Therefore, we made an attempt to synthesize zinc oxide (ZnO)-polyaniline (PANI) using chemical and emulsion polymerization techniques. The properties of ZnO-PANI films were then systematically characterized with several physical techniques. Electrochemical investigations revealed that the individual redox properties of ZnO and PANI can be maintained in a nanocomposite ZnO-PANI system. Furthermore, our results indicated that ZnO-PANI films can exhibit a wide redox potential window. Moreover, we observed the formation of a single-layer nano-Schottky junction in ZnO-PANI films, and interesting positive temperature coefficient properties in ZnO-PANI-embedded polystyrene films. Polymer Journal ( INTRODUCTIONIn recent years, there has been considerable interest among researchers to develop novel inorganic _ organic hybrid materials with compositions modulated on the nanoscale because of their many potential applications in display technologies, microelectronics, catalysis, sensors and molecular electronics. 1 The fabrication of nanocomposite films by wet chemical techniques has been proven to be a more simple and inexpensive strategy than technologically demanding physical methods. 2 Recently, Ram et al. [3][4][5][6][7][8] developed metal oxide and conducting polymer nanocomposite films of TiO 2 -PANI, TiO 2 -polypyrrole, SnO 2 -polyhexylthiophene, TiO 2 -poly (thiopheneaniline) nanocomposite, Mn-Ferrite-PANI and MWCNT-poly (o-anisidine) using wet chemical methods and used them extensively in gas sensing and molecular electronics applications. PANI is one of the most widely studied materials because of its unique electrochemical, chemical and physical properties. In addition, PANI exhibits high electrical conductivity and good environmental stability in both doped and pristine (undoped) states. 9-11 The electronic, optical, photo-electrochemical, photoconductive, photovoltaic, thermal and sensing, for example, gas sensing and biosensing, properties of PANI could be improved by incorporating PANI with polystyrene latex, multiwalled carbon nanotubes, single-walled nanotubes, montmorillonite, graphite, MCM-41, TiO 2 and SnO 2 micro and nanoparticles. 9-18 PANI composites have also been shown to possess a variety of unique mechanical, electrical and structural properties because of synergistic effect from intimate mixing

show abstract

“…The morphological evolution of the ZnO micro-javelins was followed using SEM, which led us to some interesting observations regarding the micro-javelin formation. Despite a few reports 33,34 indicating the formation of such particles, no significant attempt has been made to understand the mechanism underlying the ZnO micro-javelin formation. Fig.…”

Section: Effect Of Microwave Energy and Time Of Irradiationmentioning

confidence: 99%

Microwave-assisted synthesis of ZnO micro-javelins

et al. 2009

View full text Add to dashboard Cite

The microwave (MW)-assisted formation of ZnO micro-javelins from zinc nitrate and urea in aqueous solution is described. The particles (named as 'micro-javelins' because of their high aspect ratio and needle-like tips) grow hexagonally with well-defined facets in the h01 10i direction and pointed tips in (0001) direction. Powder X-ray diffraction patterns show the appearance of a strikingly dominant (1000) orientation. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) investigations reveal the morphological evolution of these hexagonal ZnO particles with time. The effect of precursor concentrations, counterion type and MW irradiation power and their consequent influence on pH and Zn 2+ ion concentration are investigated. A mechanism for the formation of the micro-javelins is postulated. The microwave induced supersaturation of Zn(OH) + species under the weakly basic pH condition and the initial growth through the (000 1) direction (oxygen-rich face) are proposed to be the key factors that dictate the formation of these ZnO micro-javelins. The present one-step microwave process is a straightforward and a reproducible method for the bulk synthesis of defect-free ZnO micro-javelins, which would find potential applications in microelectronic devices (e.g. lasers, cantilevers in surface probing equipment, etc.).

show abstract

Controlled Precipitation of Zinc Oxide Particles at Room Temperature

Cited by 185 publications

References 27 publications

Precipitation of monodisperse ZnO nanocrystals via acid-catalyzed esterification of zinc acetate

Precipitation of monodisperse ZnO nanocrystals via acid-catalyzed esterification of zinc acetate

Evaluating the chemio-physio properties of novel zinc oxide–polyaniline nanocomposite polymer films

Microwave-assisted synthesis of ZnO micro-javelins

Contact Info

Product

Resources

About