The Research On Synthesis Of Functional Nanoparticles Via Microwave Irradiation

The advantages of Microwave Irradiation technic are not only shorter reaction time, but also higher product yields, cleaner reactions, more green reactions. It has been extensively applied in synthesis of organic and inorganic nanomaterials in recent years. The emphasis of this thesis focuses on three sections:(1) Synthesis of a series functional semiconductor photoluminescent quantum dots via microwave irradiation technic Quantum dots are also known as semiconductor nanocrystals. Due to excellent spectral characteristics and stable optical properties, quantum dots have shown potential applications in biomedicine, thin film light-emitting devices and solar cells. CdSe semiconductor photoluminescent quantum dots were synthesized via microwave irradiation at moderate temperature (50℃～140℃), where glycerin served as heating medium. Different reacation temperatures, reaction times, molar ratios, microwave powers were employed to investigate the relationship of photophysical properties for CdSe quantum dots in different reaction conditions. The as-prepared CdSe QDs exhibited good photophysical properties. Their quantum yields were up to 70% and FWHM of the photoluminescent emission spectum peck was only 28 nm.(2) Silver nanocubes were ultrafast synthesized by microwave irradiation, usually need 20 seconds. In case of silver nanocubes, AgNO3, ethylene glycol(EG), poly(vinylpyrrolidone)(PVP) served as salt precursor, reducing agent, polymeric capping agent. And influence factors for the growth of silver nanocrystals in different reaction conditions were also discussed. The as-prepared silver nanocubes presented uniform size, well-defined shape, and the yields was over 90% after isolation.(3) N-isopropylacrylamide(NIPAM) and styrene(St) were adopted as the monomeric units, divinyl benzene(DVB) as the cross-linker, ammonium persulfate(APS) as initiator. NIPAM-St nanoparticles were rapidly synthesized, and differert reaction temperatures, reaction times, microwave powers, the concentration of St, cross-linker and ammonium persulfate(APS) were also discussed. The obtained NIPAM-St nanoparticles presented uniform size and good mondisperse.