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Preparation and characterization of ultra-fine silver bromide suspension

Król-Gracz A., Michalak E., Nowak P., Dyonizy A.

Challenges of Modern Technology

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2011

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Vol. 2, no. 2

38--42

EN

This paper present the results of studies on ultra fine-crystalline silver bromide suspensions, which were stabilized by gelatin and excess of bromide ions. Relation between dosing rate of reactants to size of obtained silver bromide crystals was investigated. Granulometric properties obtained nanocrystals were studied by turbidity method and by technique of Dynamic Light Scattering (DLS). Additionally, a photomicrograph of suspension using Scanning Electron Microscopy (SEM) was performed.

2

Photoluminescence features of AgBr nanoparticles formed in porous glass matrices

Doycho I. K., Gevelyuk S. A., Ptashchenko O. O., Rysiakiewicz-Pasek E., Tolmachova T. M., Tyurin O. V., Zhukov S. O.

Optica Applicata

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2010

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Vol. 40, nr 2

323--332

EN

The photoluminescence of AgBr nanoparticles formed by a two stage liquid-gas microsynthesis technology in two types of porous glass with different sizes of pores was investigated. Polyvinyl alcohol (Polinol) was used as a binder. It has been found that AgBr nanoparticles in the glasses with smaller pores luminesce more intensively, and we attribute this phenomenon to the differ-ences in pore size distributions. The luminescence spectra were shown to have two maxima corresponding to AgBr nanoparticles formed within the nanopores of two different sizes characteristic of each of the matrices. In both cases, the spectra excited by xenon lamp irradiation are more intensive than those stimulated by a 337-nm nitrogen laser. Comparing the maxima shifts in the phosphorescence excitation spectra with ones in phosphorescence spectra we can conclude that the luminescence and phosphorescence centers in AgBr nanoparticles are of identical nature in the matrices of both types. The investigation results fit neatly into the inherently consistent quantum confinement model and are well correlated with the poroscopic spectra of both types of glass.

3

Otrzymywanie ultra drobnokrystalicznych zawiesin bromku srebra

Dyonizy A., Nowak P., Król-Gracz A., Michalak E.

Chemik

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2010

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Vol. 64, nr 1

33-44

PL

W pracy przedstawiono wyniki badań nad syntezą ultra drobnokrystalicznych zawiesin bromku srebra, uzyskiwanych w postaci stężonych zoli stabilizowanych nadmiarem jonów bromkowych oraz żelatyną. Zbadano wpływ szybkości dozowania substratów do mieszaniny dyspersyjnej na wielkość powstających kryształów bromku srebra. Oszacowano również zmiany wielkości kryształów w czasie przechowywania zawiesin w formie żelu, w obniżonej temperaturze. Właściwości granulometryczne badano metodą turbidymetryczną dokonując pomiaru zmętnienia w czasie procesu krystalizacji oraz metodą stężeniową.

EN

This work present the results of research in ultra-fine crystals suspension of silver bromide crystals, which were received as high concentration sols stabilized by excess of bromide ions and gelatin. Relation between dosing rate of reactants to dispersion system and size of obtained silver bromide crystals was investigated. Alterations of crystals size during storing time as gel in decreased temperature, was estimated. Particle size distributions were examined by turbidity measurements using direct turbidity measurement technique in real time of crystallization process and by concentration method.