Synthesis, characterization and structure of (NH4)4[Zn5V IV4V V16O56H2(H2O)4] with a novel V5O14 layer

Abstract

A novel zinc vanadate (NH₄)₄[Zn₅V^IV₄V^V₁₆O₅₆H₂(H₂O)₄] was synthesized by the hydrothermal method and a zinc–vanadium–water system without any organic media was studied for the first time. The pH and the reaction time play important roles in the formation of the final products and the structure-change of the different products was also discussed. The new phase (NH₄)₄[Zn₅V^IV₄V^V₁₆O₅₆H₂(H₂O)₄] is a three-dimensional structure with a novel V₅O₁₄ layer connected by ZnO₄ and ZnO₆ polyhedra. The V₅O₁₄ layer in (NH₄)₄[Zn₅V^IV₄V^V₁₆O₅₆H₂(H₂O)₄] was constructed with four distorted VO₅ square pyramids and one regular VO₄ triangular pyramid which is different from the reported ones due to the pure inorganic mild synthesis conditions.