Research output: Contribution to journal › Article › peer-review
Combined HPLC-ICP-AES technique as an informative tool for the study of heteropolyniobates. / Abramov, Pavel A.; Romanova, Tamara E.; Volchek, Victoria V. et al.
In: New Journal of Chemistry, Vol. 42, No. 10, 21.05.2018, p. 7949-7955.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Combined HPLC-ICP-AES technique as an informative tool for the study of heteropolyniobates
AU - Abramov, Pavel A.
AU - Romanova, Tamara E.
AU - Volchek, Victoria V.
AU - Mukhacheva, Anna A.
AU - Kompankov, Nikolay B.
AU - Sokolov, Maxim N.
N1 - Publisher Copyright: © 2018 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
PY - 2018/5/21
Y1 - 2018/5/21
N2 - The combined HPLC-ICP-AES technique was applied to study formation of tungstoniobates and phosphomolybdoniobates. Reaction of potassium hexaniobate with tungstic acid results in the formation of mixed Nb/W Lindqvist hexametalates. The metal ratio depends on the relative amount of H2WO4 and reaction time. The most favored species are [Nb4W2O19]6- and [Nb3W3O19]5- which equilibrate with hexaniobate. Formation of [Nb2W4O19]4- was also observed; its share gradually increases with increasing amount of tungstic acid and decreasing pH. Reaction of tungstic acid with telluropentaniobate [TeNb5O19]7- results only in substitution of W for Te producing the same mixed Nb/W Lindqvist anions, but with different distribution of the individual species. The reaction of phosphomolybdic acid (H3PMo12O40) with a niobium oxalate complex, [NbO(C2O4)2(H2O)2]-, leads to the formation of mixed P/Nb/Mo Keggin anions, unambiguously detected for the first time. Only [PMo11NbO40]4- and [PMo10Nb2O40]5- were observed over the whole concentration range. No trisubstituted [PMo9Nb3O40]6- was detected in the substitution reaction, but is accessible from the self-assembly reaction of the niobium oxalate complex, phosphoric acid, and molybdate.
AB - The combined HPLC-ICP-AES technique was applied to study formation of tungstoniobates and phosphomolybdoniobates. Reaction of potassium hexaniobate with tungstic acid results in the formation of mixed Nb/W Lindqvist hexametalates. The metal ratio depends on the relative amount of H2WO4 and reaction time. The most favored species are [Nb4W2O19]6- and [Nb3W3O19]5- which equilibrate with hexaniobate. Formation of [Nb2W4O19]4- was also observed; its share gradually increases with increasing amount of tungstic acid and decreasing pH. Reaction of tungstic acid with telluropentaniobate [TeNb5O19]7- results only in substitution of W for Te producing the same mixed Nb/W Lindqvist anions, but with different distribution of the individual species. The reaction of phosphomolybdic acid (H3PMo12O40) with a niobium oxalate complex, [NbO(C2O4)2(H2O)2]-, leads to the formation of mixed P/Nb/Mo Keggin anions, unambiguously detected for the first time. Only [PMo11NbO40]4- and [PMo10Nb2O40]5- were observed over the whole concentration range. No trisubstituted [PMo9Nb3O40]6- was detected in the substitution reaction, but is accessible from the self-assembly reaction of the niobium oxalate complex, phosphoric acid, and molybdate.
KW - INDUCTIVELY-COUPLED PLASMA
KW - CAPILLARY-ELECTROPHORESIS
KW - MASS-SPECTROMETRY
KW - PHOTOCATALYTIC PROPERTIES
KW - EMISSION-SPECTROMETRY
KW - LIQUID-CHROMATOGRAPHY
KW - AQUEOUS-SOLUTIONS
KW - COMPLEXES
KW - CLUSTERS
KW - IONS
UR - http://www.scopus.com/inward/record.url?scp=85047097264&partnerID=8YFLogxK
U2 - 10.1039/c7nj03917d
DO - 10.1039/c7nj03917d
M3 - Article
AN - SCOPUS:85047097264
VL - 42
SP - 7949
EP - 7955
JO - New Journal of Chemistry
JF - New Journal of Chemistry
SN - 1144-0546
IS - 10
ER -
ID: 13468687