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Updated: Aug 2, 2026
Chemical Precipitation Method for the Synthesis of Nb2O5 Modified Bulk Nickel Catalysts with High Specific Surface Area
Published on: February 19, 2018
Synthesis, characterization, and crystal structures of two novel high-nuclear nickel-substituted dimeric
Zhiming Zhang1, Yangguang Li, Enbo Wang
1Institute of Polyoxometalate Chemistry, Department of Chemistry, Northeast Normal University, Changchun 130024, People's Republic of China.
Abstract:
Two novel high-nuclear Ni-substituted polyoxometalates Na9K[Ni7(OH)4(H2O)(CO3)2(HCO3)(A-alpha-SiW9O34)(beta-SiW10O37)].5H3O.18H2O (1) and K6Na4[{Ni6(H2O)4(mu2-H2O)4(mu3-OH)2}(x-SiW9O34)2].17.5H2O (2) have been obtained by reaction of K(8)[gamma-SiW10O36] with NiCl2.2H2O in basic conditions. Compounds 1 and 2 all represent the first polyoxometalates substituted by seven and six Ni centers, respectively. Also, compound 1 exhibits a novel asymmetric dimeric structure, composed of [A-alpha-SiW9O34]10- and [beta-SiW10O37]10- units linked by a Ni7 cluster and three carbonates, which exhibit tri- and bidentate coordination modes in 1.
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