Novel Size-Tunable and Straightforward Ultra-Small Nanoparticle Synthesis in a Varying Concentration Range of Glycerol as a Green Reducing Solvent

Despite all the possibilities available so far for thesynthesisof nanoparticles (NPs), synthesizing ultra-small (<10 nm) monodispersedparticles is still demanding. Getting aparticular size with a straightforward method is a trial-and-errorapproach. To explore this prospective, in the current study, we haveintroduced a protocol which offers a varying concentration range ofglycerol to successfully generate the NPs of repeatable and consistentparticle size in each synthesis, thus giving an alternative from lengthytentative preparations and/or testing protocols. Since synthesizingcontrolled sized nanoparticles in aqueous medium is somewhat difficultas the balance of particle growth and nucleation is challenging tocontrol, herein, we used a polyol method with glycerol both as a solventmedium as well as reducing species for silver nitrate, as an examplemodel ion source, to execute the nanoparticle synthesis. In orderto maintain the stability of the synthesized NPs, polyvinylpyrolidone(PVP) was added as a stabilizer. The synthesis, monodispersity, andstability were confirmed using techniques such as UV-vis spectroscopy,Fourier transform infrared spectroscopy (FTIR), dynamic light scattering(DLS), and X-ray powder diffraction (XRD), while morphological analysisand ultra-small size validation were conducted using TEM, SEM, andAFM. Interestingly, in the various concentrations of glycerol solutionused (10-100%), we have observed a tunable linear size rangeto obtain ultra-small nanoparticles (<10 nm) up to 60% glycerol,while further increasing the glycerol component increased the sizeapproximately to & SIM;160 nm, providing tunable properties in thissynthesis procedure. Hence, this study provides a distinct possibilityto obtain ultra-small nanoparticles with a tunable size feature forfurther applications in numerous fields.