Low temperature property of Ni3(PO4)2.8H2O; NaOH

An inorganically template metaphosphoric acid-containing nickel salt, nanomaterial, has been synthesized and characterized with different measurement techniques such as differential scanning calorimeter (DSC), ultraviolet–visible and near infrared (UV–Vis–NIR) absorption spectroscopy, transmission electron microscopy (HRTEM), vibrating sample magnetometer and X-ray powder diffraction. The thermal property of this mixture has been studied at a low temperature up to 223 from 303 K with DSC. The specific heat capacity of this mixture has been measured in atmospheric O2 at a rate of 10 K min−1 from 303 to 223 K and vice versa in two thermal cycles. The net specific heat capacity of this mixture is found to be 1747.86 J kg−1 K−1 and −6401.38 J kg−1 K−1 in first and second thermal cycles, respectively. There is a discontinuity in the specific heat at 98 s for 233 K and 9 s for 238 K. This average crystallite size of this nanomaterial is ~23.5 nm. The paramagnetic Curie temperature (θ P) and Curie constant (C) are 34.77 K and 9.11 × 10−3, respectively. This material found was an insulator from UV–Vis–NIR measurements.