Fundamental aspects of copper electrodeposition in the hydrogen Co-deposition range

This a review paper considering fundamental aspects of copper electrodeposition at high overpotentials where parallel to copper electrodeposition, hydrogen evolution reaction occurs. The two types of copper deposits are formed in the hydrogen co-deposition range: (a) the open and porous structures denoted as the honeycomb-like ones, and (b) powdered deposits. Phenomenology of the formation of the honeycomb-like structure, as well as factors affecting the formation of this type of structure are described in detail. The increase of the specific surface area of the honeycomb-like structure by the application of the periodically changing regimes of electrolysis, such as pulsating overpotential (PO) regime is considered. Correlation between the shape of copper powder particles and the quantity of evolved hydrogen by which they are formed was also presented.Ovo je pregledni rad koji razmatra fundamentalne aspekte elektrohemijskog taloženja bakra na visokim prenapetostima gde paralelno procesu elektrohemijskog taloženja bakra se odigrava reakcija izdvajanja vodonika. Dva tipa taloga bakra su formirana u oblasti ko-depozicije vodonika: (a) otvorene i porozne strukture označene kao strukture pčelinjeg saća, i (b) praškasti talozi. Fenomenologija formiranja strukture pčelinjeg saća, kao i faktori koji utiču na formiranje ovog tipa strukture su detaljno opisani. Povećanje specifične površine strukture pčelinjeg saća primenom periodično promenljivih režima elektrolize, kao što je režim pulsirajuće prenapetosti (PP), je razmatran. Uzajamna veza između oblika čestica praha i količine vodonika izdvojene tokom njihovog formiranja je takođe predstavljena

Формирање металних прахова електролизом: облик честица као функција густине струје измене и пренапетости за реакцију издвајања водоника

The short survey of the dependence of the shape of electrolytically produced powder particles on the exchange current density for metal deposition and overpotential for hydrogen evolution reaction is presented. The decrease of the exchange current density leads to a branching of dendrites and their transformation from needle-like and the two-dimensional (2D) fern-like to the three-dimensional (3D) pine-like shapes. Vigorous hydrogen evolution inhibits the dendritic growth leading to a formation of cauliflower-like and the spongy-like particles. The very thin needles were obtained by molten salt electrolysis. Mechanisms responsible for the formation of both the dendritic (the general theory of disperse deposits formation) and the cauliflower-like and the spongy-like particles (the concept of „effective overpotential”) were also mentioned.Приказан је кратак преглед зависности облика електролитички произведених металних прахова од густине струје измене таложења метала и пренапетости за реакцију издвајања водоника. Смањење густине струје измене доводи до гранања дендрита и њихове трансформације од игличастих и дводимензионалних (2Д) налик папрати, до тродимензионалних (3D) дендрита налик стаблу бора. Интензивно издвајање водоника инхибира дендритични раст доводећи до формирања карфиоластих и сунђерастих честица. Веома фине игле су добијене електролизом из растопа. Такође су разматрани механизми одговорни за формирање и дендритичних (општа теорија формирања дисперзних талога) и карфиоластих и сунђерастих честица (концепт „ефективне пренапетости“).Lecture at the Meeting of Electrochemical Division of the Serbian Chemical Society held on 30 September 2019

Influence of the exchange current density and overpotential for hydrogen evolution reaction on the shape of electrolytically produced disperse forms

In this study, comprehensive survey of formation of disperse forms by the electrolysis from aqueous electrolytes and molten salt electrolysis has been presented. The shape of electrolitically formed disperse forms primarily depends on the nature of metals, determined by the exchange current density (j0) and overpotential for hydrogen evolution reaction as a parallel reaction to metal electrolysis. The decrease of the j0 value leads to a change of shape of dendrites from the needle-like and the 2D fern-like dendrites (metals characterized by high j0 values) to the 3D pine-like dendrites (metals characterized by medium j0 values). The appearing of a strong hydrogen evolution leads to formation of cauliflower-like and spongy-like forms (metals characterized by medium and low j0 values).The other disperse forms, such as regular and irregular crystals, granules, cobweb-like, filaments, mossy and boulders, usually feature metals characterized by the high j0 values. The globules and the carrot-like forms are a characteristic of metals with the medium j0 values. The very long needles were a product of molten salt electrolysis of magnesium nitrate hexahydrate. Depending on the shape of the disperse forms, i.e. whether they are formed without and with vigorous hydrogen evolution, formation of all disperse forms can be explained by either application of the general theory of disperse deposits formation or the concept of "effective overpotential". With the decrease of j0 value, the preferred orientation of the disperse forms changed from the strong (111) in the needle-like and the fern-like dendrites to randomly oriented crystallites in the 3D pine-like dendrites and the cauliflower-like and the spongy-like forms

Mesto Zapadnog Balkana u agendama Rusije i Turske u kontekstu hibridnih pretnji

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Exploring trends in environmental pollution and hazardous chemical waste reporting

In contemporary society, environmental pollution and hazardous chemical waste are pressing concerns. This study investigates reporting trends related to environmental pollution and hazardous chemical waste in twelve scientific journals and daily newspapers. Notably, we found that the year 2013 marked a significant peak with the highest number of articles on these topics. Understanding the publishing and reporting trends of these subjects is pivotal for informed public education and underscores the significant influence of scientific research in shaping media reporting. As the global community faces increasing environmental challenges, accurate and scientific-based reporting is essential for fostering public awareness and facilitating effective solutions

Magneto-elektrohemija - osnovne činjenice i uticaji primenjenog magnetnog polja na koroziju metala, prenos mase, kinetiku procesa i preferencijalnu orijentaciju taloga

In this work, the theoretical survey of the basic facts about magneto electrochemistry will be given. It will be analyzed the effects of the applied magnetic fields on kinetic of the electrochemical processes, mass transfer in the electrochemical cell, corrosion of metals and preferred orientation of metal deposits.U ovom radu biće date teorijske osnove na kojima se zasnivaju principi magneto-elektrohemije. Analiziraće se uticaji koji primenjena magnetna polja mogu da imaju na kinetiku elektrohemijskih procesa, prenos mase u elektrohemijskoj ćeliji, koroziju metala i na preferencijalnu orijentaciju taloga

Magneto-elektrohemija - osnovne činjenice i uticaji primenjenog magnetnog polja na koroziju metala, prenos mase, kinetiku procesa i preferencijalnu orijentaciju taloga

In this work, the theoretical survey of the basic facts about magneto electrochemistry will be given. It will be analyzed the effects of the applied magnetic fields on kinetic of the electrochemical processes, mass transfer in the electrochemical cell, corrosion of metals and preferred orientation of metal deposits.U ovom radu biće date teorijske osnove na kojima se zasnivaju principi magneto-elektrohemije. Analiziraće se uticaji koji primenjena magnetna polja mogu da imaju na kinetiku elektrohemijskih procesa, prenos mase u elektrohemijskoj ćeliji, koroziju metala i na preferencijalnu orijentaciju taloga