Effect of Synthesis Conditions on the Size and Morphology of Magnetic Nickel Particles

Abstract

This study compares the properties of nickel (Ni) particles synthesized through the chemical-reduction-reactions (CRRs) under open-atmosphere and pressurized (solvothermal) conditions. The primary objective was to produce Ni particles with sizes below 100 nm with smooth surfaces, single-phase composition, highly crystalline, mono-disperse, and magnetic which are essential for constructing nanostructured Ni suitable for diverse applications. CRRs were conducted in a glass beaker for ambient pressure synthesis and a solvothermal reactor for pressurized conditions. The structural, morphological, and magnetic characteristics of the samples were investigated in detail. The findings demonstrated that the manipulation of the synthesis conditions in both methods allowed the formation of Ni particles with a wide range of morphologies, crystallinity, and purity. Besides, particle sizes varied from nanometer to micrometer scale, depending on the synthesis approach and processing conditions. Moreover, the relation between magnetic characteristics and morphological features was discussed in detail. Therefore, this research provides a comparative evaluation of two different synthesis methods, offering insight into the optimization of conditions for producing phase-pure, magnetic, and equiaxed Ni nanoparticles (NPs). By addressing the challenge of achieving mono-disperse Ni NPs, this study contributes to the understanding of synthesis techniques and elucidating the mechanisms underlying the formation of magnetic Ni NPs.