Exploring a new vanadophosphate Li(C4N2H12)2[(HPO4)(VO)3(PO4)3]: Synthesis, Characterization, and catalytic behavior

Abstract

Li(C4N2H12)2[(HPO4)(VO)3(PO4)3], a new vanadophosphate (VPO) material we synthesized using a hydrothermal route, crystallizes in the orthorhombic system (S.G.: Pna21), with the cell parameters: a = 14.6207(7) Å, b = 8.7090(3) Å, c = 17.6208(7) Å, V = 2243.69(16) (Å3), Z = 4. The crystal structure consists of bc-parallel layers of alternating polyhedra VO5, VO6 combined with PO4 or HPO4 tetrahedra. The layers stack provides cavities hosting Li+ cations. Within the interlayer space, protonated organic molecules act as a template and create hydrogen bonding interactions with the inorganic network. To assess its properties, the hybrid material’s thermal stability and reactivity were investigated using the IR spectroscopy and thermal analysis (TG/DTA). The potential of the title compound was investigated on the adsorptive removal of methylene blue (MB) dye by studying various parameters like pH, temperature, initial dye concentrations and contact time. The kinetic study revealed a gradual process of the dyés adsorption, with a removal efficiency of 99 % for initial MB concentrations of 50 ppm at pH = 7. The degradation MB continues even after three hours of oxidative reaction.