Solution Synthesis Of Micro-/Nano-Materials

Nanomaterials has been paid universal attentions for their prominent optical, electrical, magnetic and catalyze properties. Its application relates to every domain of material and has become one of its most important and attractive part. It is reported that the size and morphology of nanomaterial have obvious influences on properties, so the controllable synthesis is very important and significant. During which the exploration of microstructure, formation mechanism and growth kinetic all are key to the future experiments.Various methods have been developed for synthesizing nanomaterials, among of which the solution synthesis has many merits, For example, the reacting condition is relatively simple and mild, and the obtained product is much more pure and monodisperse. So we adopted solution synthesis herein and have obtained several important nano-functional materials, in addition we studied their elementary applied properties. The primary content of this paper is as following.Synthesis and characterization of Prussian blue microstructures morphology controllable M3[Co(CN)6]2(M=Zn, Co, Ni) microstructures were synthesized in solution under ultrasonic condition. herein we mainly studied Zn3[Co(CN)6]2. Uniform Zn3[Co(CN)6]2 microspheres and polyhedrons were synthesized, and TEM, SEM were carried out to characterize the morphologies. Experimental parameter influences were also carried out in detail. What's interested us here is that self-assembly were observed obviously when the microparticles dispersed in alcohol were dropped on a copper grid or a glass substrate without any further treatment. Further investigation suggested that both spheres and polyhedrons are aggregated by small nanoparticles. N2 adsorption measurements verified the existence of micro-pores in both Zn3[Co(CN)6]2 microspheres and micropolyhedrons. The BET surface area of spheres and polyhedrons are 428.20, 441.36 m2g-1 respectively. The total pore volume are 0.2157, 0.2395 cm3g-1 respectively.Synthesis and characterization ofα-Fe2O3 urchin-like hollow nanostructures hollow and solid urchins were obtained in hydrothermal condition under the assistance of ligand. XRD, TEM, SEM were carried out to characterize the composition and morphology of the urchins. It is obviously seen that both hollow and solid urchins are composed of small nanoflakes. Series of experiments were also carried out to discuss the influences of experimental parameters. the two-step formation mechanism was speculated firstly and then verified by experiments. Magnetic and N2 adsorption properties were also carried out. The hysteresis loops at 5K and 300K clearly confirm the fact that hematite behaves antiferromagnetic at low temperature and weak ferromagnetism above morin transition temperature (TM). zero-field-cooled (ZFC) and field-cooled (FC) curves split during the whole temperature region. Normally, bulk hematite has a Morin transition from the low-temperature antiferromagnetic phase to a weakly ferromagnetic phase at 263 K. But here it should be noted that the TM value in differential ZFC curve (inset in Figure 5c) is found to be 181 K, which is much lower than the bulk transition temperature. N2 adsorption measurements illuminated the micro-pore structure ofα-Fe2O3 hollow urchins. The BET surface are is 30.68m2g-1, which is much larger than that of the submicron particles.Synthesis and characterization of PbS microstructures star-shaped dendrites and strips were synthesized in hydrothermal system at the assistance of surfactant(PVP), XRD, TEM, SEM were carried out to characterize the composition and morphologies. In addition, we studied the IR-VIS spectrum of both dendrites and strips.