Synthesis, crystal structure analysis, catalytic and biological activities of (H2en)3{V10O28}.6H2O. An improved refinement

•A hybrid decavanadate of (H2en)3{V10O28}.6H2O was chemically crystallized by controlling pH, and its crystal structure has been determined by crystal X-ray diffraction.•The crystals are stable under 100 °C.•The compound exhibits medium antimicrobial and low antioxidant activities.•The decavanadate compound's catalytic activity was tested by oxidizing methylene blue with hydrogen peroxide under varied conditions. The greatest outcomes were obtained using hotter and acidic conditions. The hybrid material, (H2en)3{V10O28}.6H2O (1), containing decavanadate units was synthesized by a wet chemistry method using ethylenediamine (en) as a structure-directing agent. It crystallizes in the monoclinic system, space group C2/c, with cell parameters (Å, °): a = 20.2028 (3), b = 17.0629 (3), c = 10.5541 (2), β= 104.2045 (16). The crystal structure forms a 3D framework of isolated [V10O28]6− monomers, ethylenediammonium cations, and H2O molecules linked through NH···O and OH···O hydrogen bonds. The Fourier transform infrared spectroscopy exhibits characteristic bands corresponding to decavanadate groups and organic molecules. The thermal decomposition steps of the hybrid compound show mainly the loss of the organic moieties and the water molecules. The decavanadate compound's catalytic activity was evaluated by oxidizing methylene blue (MB) with hydrogen peroxide. The biological activity of 1 yielded mediocre results.