Comparative Morphological and Crystallographic Analysis of Electrochemically- and Chemically-Produced Silver Powder Particles

Abstract

Silver powders chemically synthesized by reduction with hydrazine and those produced by electrolysis from the basic (nitrate) and complex (ammonium) electrolytes were examined by X-ray diffraction (XRD) and scanning electron microscopic (SEM) analysis of the produced particles. Morphologies of the obtained particles were very different at the macro level. The needle-like dendrites, as well as the mixture of irregular and regular crystals, were formed from the nitrate electrolyte, while the highly-branched pine-like dendrites with clearly noticeable spherical grains were formed from the ammonium electrolyte. The agglomerates of spherical grains were formed by reduction with hydrazine. In the particles obtained from the nitrate electrolyte, Ag crystallites were strongly oriented in the (111) plane. Although morphologies of Ag particles were very different at the macro level, the similarity at the micro level was observed between chemically-synthesized particles and those obtained by electrolysis from the ammonium electrolyte. Both types of particles were constructed from the spherical grains. This similarity at the micro level was accompanied by the similar XRD patterns, which were very close to the Ag standard with a random orientation of Ag crystallites. For the first time, morphologies of powder particles were correlated with their crystal structure.

Morphology, Structure and Mechanical Properties of Copper Coatings Electrodeposited by Pulsating Current (PC) Regime on Si(111)

“…The preferred orientation of Cu coatings was estimated by determining the "Texture Coefficient", TC(hkl) and the "Relative Texture Coefficient", RTC(hkl) [39][40][41]. The procedure for the determination of these coefficients is described in Appendix B.…”

“…In the XRD pattern of the Cu coating electrodeposited with a frequency of 30 Hz, the predominant orientation of Cu crystallites in the (220) crystal plane was observed. The preferred orientation of Cu coatings was estimated by determination of the "Texture Coefficient" (TC(hkl)) and "Relative Texture Coefficient" (RTC(hkl)) [40,41]. It is necessary to note that the TC(hkl) values larger than 1.00 indicate the existence of the preferred orientation in the (hkl) plane.…”

“…It is necessary to note that the TC(hkl) values larger than 1.00 indicate the existence of the preferred orientation in the (hkl) plane. Simultaneously, since four reflections in the 2θ range between 30 • and 95 • were recorded, the values of RTC(hkl) coefficients larger than 25% indicate the existence of the preferred orientation [40,41].…”

“…The ratio of reflection intensity (hkl) to the sum of all intensities of the recorded reflections, R (hkl), (in %) is given by Equation (A8) [39][40][41]:…”

Synthesis and characterization of novel stellate sea-urchin-like silver particles with extremely low density and superhydrophobicity

“…21,22 Electrolysis is widely used in the production of silver powders. 23,24 Silver nanodendrites are synthesized by electrodeposition 25 and reduction from AgNO 3 . 26 In physical processes, Ag particles are generally synthesized by evaporation-condensation method or by laser ablation of metallic bulk materials in solution.…”