"Nanotechnology and nanomaterials"

Controlled synthesis of palladium and nickel nanomaterials
Dobrovetska O.1, Saldan I.2, Pereviznyk O.2, 
Bilan O.1,3, Reshetnyak O.2, Kuntyi O.1
1 Institute of Chemistry, Lviv Polytechnic National University, Bandery St. 12, 79013-Lviv, Ukraine, E-mail: oksana_dobrovetska@ukr.net
2 Department of Physical and Colloid Chemistry, Ivan Franko National University of Lviv. Kyryla and Mefodia St. 6, 79005-Lviv, Ukraine
3 Industrial Company “Autonomous Power Sources”, Lvivska St. 2, 80074-Velyki Mosty, Ukraine

Activity of bulk metals might be limited in comparison with nanodispersed and well distributed metal nanoparticles (NPs), that show unexpectedly high catalytic activity in various chemical reactions. Detailed studies of nanostructured NPs confirmed that their catalytic activity essentially depends on their size wherever they are introduced – on a solid support, an electrode surface or even a colloidal solution [1]. For mono- or bimetallic NPs, together with physical and chemical syntheses, electrochemical methods are highly reproducible and handy in practice [2]. Electrodeposition constitutes a suitable method since it is not expensive and enables to form nanomaterials with a wide range of sizes and shapes.
The obtained experimental results confirmed the appearance of Pd and/or Ni NPs on graphite during the beginning of electrodeposition in pulse mode. Well distributed NPs with size ≤100 nm in diameter were found by SEM observation after 3-50 pulse cycles. A paraboloid dependence of the mean value of the particle size and particle number per surface area on the number of pulse cycles was experimentally found [3]. 

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3.	Saldan I., Girella A., Milanese C., Fratini E., Dobrovetska O., Levchuk I., Kuntyi O. Size and distribution of palladium nanoparticles electrodeposited on graphite // Functional Mater.- 2018.-25.-P. 82-87.