Nickel selenate: a deep and efficient characterization

Abstract

This work aims to determine the nickel selenate hexahydrate thermal behavior by simultaneous thermogravimetry–differential thermal analysis and differential scanning calorimetry and characterize its thermal intermediates decomposition. Moreover, at 25 °C, this material is a green-colored compound; however, with the temperature increase (until 420 °C), a color change from yellowish green to yellowish orange and finally to yellow was observed. This characteristic is due to the water molecules release, changing the ultraviolet–visible/near-infrared spectroscopy analysis absorption spectra and consequently modifying the crystal structure, as confirmed by X-ray powder diffraction, and resulting in visual changes in photo-DSC. The new data are essential to determine the better conditions to use this material as a precursor in synthesis and also to use it in future applications.