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In this paper, we report a simple yet powerful synthetic method for obtaining monodispersed silver nanoparticles by direct thermal decomposition of two materials — one is silver acetate as a source of the metal core and the other is myristic acid as a capping agent. The reaction was performed at 250°C, the boiling point of myristic acid, without additional solvent. The nucleation and growth of the particles were monitored by dynamic light scattering in order to optimize the reaction time. By this simple procedure, we could obtain uniformly sized Ag nanoparticles with the average diameter of 4.8 ± 0.1 nm. Although the particles were synthesized at high temperature, the ligand exchange between myristates and alkanethiolates can be achieved at room temperature. Significant characteristics of Ag nanoparticles attributed to localized surface plasmons were investigated.

This paper reports on the preparation of high purity ZnS nanoparticles by a facile single step solvent-free route via thermal decomposition of zinc acetate dihydrate and thiourea in air atmosphere. The third-order optical nonlinearity of the prepared ZnS nanoparticles were measured by Z-scan technique using continuous wave 532-nm diode pumped Nd:YAG laser. From nonlinear optical (NLO) measurements, the prepared ZnS nanoparticles possess negative nonlinearity i.e., self-defocusing. Open aperture Z-scan measurement shows saturable absorption within the medium. These results show that the prepared ZnS nanoparticles are promising candidate for various potential applications in the field of nonlinear optics.

For exploring the interesting solvent effect on structure and morphology, a variety of MgWO₄ nanoparticles were prepared by a one-pot solvothermal method with different proportional solvents of water and ethylene glycol. The results showed that monoclinic wolframite crystalline structure of MgWO₄ was successfully synthesized, corresponding to two standard cards of MgWO₄ (JCPDS No. 27-0789) and MgWO₄ (JCPDS No. 19-0776), respectively. The morphology of MgWO₄ nanoparticles presents eight different shapes and orderly transforms from one shape to another with increasing water content in mixed EG-water solvents, and a possible mechanism was proposed. The catalytic activities of these MgWO₄ nanoparticles on the thermal decomposition of Ammonium Perchlorate (AP) were compared using differential scanning calorimetry (DSC) method, and found to present good change rule with particle size.