Pawel Uznanski

Pawel Uznanski

orcid

Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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23 March 2017 in Journal of Nanoparticle Research
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Journal Article
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PUPawel Uznanski
Pawel Uznanski
JZJoanna Zakrzewska
Joanna Zakrzewska
FFFrederic Favier
Frederic Favier
SKSlawomir Kazmierski
Slawomir Kazmierski
EBEwa Bryszewska
Ewa Bryszewska
A comparative study of amine and silver carboxylate adducts [R1COOAg-2(R2NH2)] (R1 = 1, 7, 11; R2 = 8, 12) as a key intermediate in NPs synthesis is carried out via differential scanning calorimetry, solid-state FT-infrared spectroscopy, 13C CP MAS NMR, powder X-ray diffraction and X-ray photoelectron spectroscopy, and various solution NMR spectroscopies (1H and 13C NMR, pulsed field gradient spin-echo NMR, and ROESY). It is proposed that carboxyl moieties in the presence of amine ligands are bound to silver ions via chelating bidentate type of coordination as opposed to bridging bidentate coordination of pure silver carboxylates resulting from the formation of dimeric units. All complexes are packed as lamellar bilayer structures. Silver carboxylate/amine complexes show one first-order melting transition. The evidence presented in this study shows that phase behavior of monovalent metal carboxylates are controlled, mainly, by head group bonding. In solution, insoluble silver salt is stabilized by amine molecules which exist in dynamic equilibrium. Using (bis)amine-silver carboxylate complex as precursor, silver nanoparticles were fabricated. During high-temperature thermolysis, the (bis)amine-carboxylate adduct decomposes to produce silver nanoparticles of small size. NPs are stabilized by strongly interacting carboxylate and trace amounts of amine derived from the silver precursor interacting with carboxylic acid. A corresponding aliphatic amide obtained from silver precursor at high-temperature reaction conditions is not taking part in the stabilization. Combining NMR techniques with FTIR, it was possible to follow an original stabilization mechanism. The synthesis of a series (bis)alkylamine silver(I) carboxylate complexes in nonpolar solvents were carried out and fully characterized both in the solid and solution. Carboxyl moieties in the presence of amine ligands are bound to silver ions via chelating bidentate type of coordination. The complexes form layered structures which thermally decompose forming nanoparticles stabilized only by aliphatic carboxylates.

12 April 2011 in Plasma Processes and Polymers
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Journal Article
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AWAleksander M. Wrobel
Aleksander M. Wrobel
IBIwona Blaszczyk‐Lezak
Iwona Blaszczyk‐Lezak
PUPawel Uznanski
Pawel Uznanski
BGBartosz Glebocki
Bartosz Glebocki

1 September 2018 in Surface and Coatings Technology
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Journal Article
Closed access
PUPawel Uznanski
Pawel Uznanski
BGBartosz Glebocki
Bartosz Glebocki
AWAgnieszka Walkiewicz-Pietrzykowska
Agnieszka Walkiewicz-Pietrzykowska
JZJoanna Zakrzewska
Joanna Zakrzewska
AWAleksander M. Wrobel
Aleksander M. Wrobel
Jacek TyczkowskiJacek Tyczkowski
Jacek Tyczkowski

1 March 2011 in Advanced Materials
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Journal Article
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FSFrancesco Di Stasio
Francesco Di Stasio
PKPlaton Korniychuk
Platon Korniychuk
SBSergio Brovelli
Sergio Brovelli
PUPawel Uznanski
Pawel Uznanski
SMShane O. McDonnell
Shane O. McDonnell
Franco CacialliFranco Cacialli
Franco Cacialli

29 December 2009 in Journal of Materials Science
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Journal Article
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PUPawel Uznanski
Pawel Uznanski
EBEwa Bryszewska
Ewa Bryszewska

11 August 2012 in Thin Solid Films
Verified
Journal Article
Closed access
AWA.M. Wrobel
A.M. Wrobel
AWA. Walkiewicz-Pietrzykowska
A. Walkiewicz-Pietrzykowska
PUPawel Uznanski
Pawel Uznanski
BGB. Glebocki
B. Glebocki