Sinteza i strukturna karakterizacija mikroporoznih arsenata i fosfata
Synthesis and structural characterization of microporous arsenates and phosphates
Author
Kovač, Sabina Z.Mentor
Karanović, LjiljanaCommittee members
Vulić, PredragĐorđević, Tamara
Metadata
Show full item recordAbstract
Predmet rada i istraživanja ove doktorske disertacije su sinteza i strukturne
karakteristike novih kristalnih arsenata i fosfata koji sadrže Mg, K, Ca, Mn, Fe, Co, Ni,
Cu, Zn, Sr, Ba i druge katjone. U strukturama arsenata i fosfata, AsO4- i PO4-tetraedri
najčešće se vezuju sa tetraedarski ili oktaedarski koordinisanim katjonima prelaznih
metala formirajući otvorene strukture (slojeve ili 3D mreže) sa širokim opsegom
različitih topologija. U šupljinama ili porama u obliku povezanih ili nepovezanih
kanala, tunela, kaveza i međuslojnog prostora mogu se ugraditi različiti vanmrežni joni
(obično alkalni i zemnoalkalni katjoni) ili molekuli (najčešće mali organski molekuli),
što čini ova jedinjenja veoma interesantnim zbog njihovih fizičkih i hemijskih osobina i
potencijalne primene.
U okviru ispitivanja sistema T1O–T2O–X2O5–(H2O)–Y, gde je T1 dvovalentni ili
jednovalentni (K+, Ca2+, Zn2+, Sr2+, Ba2+), T2 dvovalentni ili trovalentni (Mg2+, Mn2+,
Fe2+, Co2+, Ni2+, Cu2+, Zn2+, Fe3+, Co3+), X ...petovalentni (P5+, As5+) katjon, a Y je
vanmrežni katjon H2(C2H8N2)2+ ili NH4
+ sintetisana su nova jedinjenja metodom
niskotemperaturne hidrotermalne sinteze i određene njihove kristalne strukture. Cilj je
bio da se u okviru ovog sistema sintetišu monokristali koji u mikroporama ili
međuslojnom prostoru sadrže različite jone i molekule kao što je etilendiamin,
C2H4(NH2)2, ili odgovarajuća protonovana forma.
Kvalitet dobijenih monokristala proveravan je pomoću optičkog mikroskopa ili
binokularne lupe i strukture kristala određene su metodom rendgenske difrakcije na
monokristalu. Za morfološku i hemijsku karakterizaciju korišćena je metoda skenirajuće
elektronske mikroskopije (SEM) dopunjena energetsko-disperzivnim sistemom (EDS).
Kod kristala koji su zahtevali preciznu kvantitativnu hemijsku analizu korišćena je
elektronska mikrosonda, a metoda ramanske spektroskopije korišćena je za određivanje
prisustva H2O, (OH)−, (NH4)+ i NH3.
Pokazano je da četiri sintetisana kristala imaju zeolitski DFT-tip strukture. To su
(H2en)[ZnAsO4]2 (ZnAs), (H2en)[Co0,1Zn0,9AsO4]2 (ZnCoAs),...
The doctoral dissertation research subjects are the synthesis and structural
investigation of new arsenate and phosphate containing Mg, K, Ca, Mn, Fe, Co, Ni, Cu,
Zn, Sr, Ba and other cations. In the structures of arsenates and phosphates, AsO4- and
PO4-tetrahedra are usually linked with tetrahedrally and octahedrally coordinated
cations of transition metals forming open structures (layers or 3D frameworks) with a
wide range of different topologies. In the holes, or pores, which are in the form of a
connected or unconnected channels, tunnels, cages and the interlayered space, various
non-framework ions (usually alkaline and earth alkaline cations) or molecules (usually
small organic molecules) can be incorporated. Therefore these compounds are very
interesting due to their physical and chemical properties and potential applications.
In the course of the investigation of the T1O–T2O–X2O5–(H2O)–Y system,
where T1 is a divalent or monovalent (K+, Ca2+, Zn2+, Sr2+, Ba2+), T2 divalent or
tr...ivalent (Mg2+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+, Fe3+, Co3+), X pentavalent (P5+,
As5+) cation, and Y is non-framework cation H2(C2H8N2)2+ or NH4
+, several novel
compounds have been synthesized using the low temperature hydrothermal synthesis
method, and their crystal structures have been determined. The aim was to synthesize
single crystals with micropores or interlayer space containing different ions and
molecules like the ethylenediamine, C2H4(NH2)2, or the corresponding protonated
forms.
The quality of the obtained single crystals was evaluated using an optical or
binocular microscope, and the crystal structure was solved using single-crystal X-ray
diffraction data. For the morphological and chemical characterization the scanning
electron microscopy (SEM), coupled with energy-dispersive system (EDS) was used.
The electron microprobe provide precise quantitative chemical analysis, and the Raman
spectroscopy method was used for the determination of the presence of H2O, (OH)−,
(NH4)+ and NH3...