Abstract
Pure NiSe nanoparticles were successfully produced using an adapted thermal treatment technique and an alternate nitrogen flow. Throughout a range of calcination temperatures of 500 degrees C-800 degrees C, a number of techniques were utilised in order to examine the optical, structural and magnetic characteristics of the attained NiSe nanoparticles. Ultravioletvisible absorption spectrophotometry was employed to ascertain the optical characteristics. These evidenced a reduction in the NiSe nanoparticle conduction band with elevated calcination temperatures, i.e. from3.58 eV to 3.37 eV at 500 degrees C and 800 degrees C, respectively. This was attributed to a higher degree of attraction between the conduction electrons and the metallic ions with rising particle dimensions, equating to a larger atom population comprising the metal nanoparticles. This means that the findings can be applied to a wide range of energy applications. The lack of impurities within the produced NiSe nanoparticles was verified utilising Fourier-transform infrared spectroscopy and energy dispersive X-ray analysis. At calcination temperatures of similar to 500 degrees C, powder X-ray diffraction demonstrated that the specimen, amorphous at room temperature, had undergone conversion into hexagonal crystalline nanostructures. Transmission electron microscopy confirmed the evolution of size NiSe nanoparticles; mean particle dimensions increased from 21 nm to 54 nm at calcination temperatures of 500 degrees C and 800 degrees C, respectively. Electron spin resonance spectroscopy, used to identify the magnetic properties, supported the presence of unpaired electrons. (C) 2022 The Author(s). Published by Elsevier B.V.