【摘要】 利用溶胶-凝胶法在非水体系中合成出ZnO量子点,并用3-氨丙基三乙氧基硅烷(APTES)对其进行包覆,制得水溶性ZnO/氨丙基-硅氧烷量子点(ZnO-ASQDs)。通过实验确定最佳包覆条件:t=60℃,T=30min,nSi:nZn=1:1,VPEG/Vtotal=1/9。合成的ZnO量子点分别在348与512nm处有2个荧光发射峰,且激发区域较宽(220~360nm)。经过APTES包覆,ZnO量子点荧光发射强度明显增强,同时具有良好的水溶性与荧光稳定性,稳定时间可达60d之久。由Brus公式计算表明,包覆层对ZnO量子点不但改性还起到保护作用,抑制其团聚。经XRD与TEM证实,ZnO-ASQDs具有核壳结构,ZnO核平均粒径为6nm,整体粒径约为20nm。此外,通过调整ZnO核的粒径可制备出不同荧光颜色的ZnO-ASQDs。更多还原

【Abstract】 ZnO quantum dots were synthesized by Sol-gel method in non-aqueous system.The resultant ZnO quantum dots were coated by 3-Aminopropyl triethoxysilane(APTES) to obtain water-solube ZnO/Aminopropylsiloxane quantum dots(ZnO-AS QDs).The optimum coating conditions are determined to be as t =60 ℃,T = 30 min,nSi:nZn=1:1,VPEG/Vtotal=1/9.Two fluorescence emission peaks at 348 and 512 nm are observed,which may be excited in the 220~360 nm excitation range.While the ZnO quantum dots are coated by APTES,it is shown that the fluorescence emission intensity increases obviously with the same excitation range.After being coated,the ZnO quantum dots show good water-solubility up to 60 d,as well as good stability of the fluorescence properties in aqueous solution.The calculation results from the Brus equation show that the coating not only modifies ZnO quantum dots but also plays a protective role to restrain particle arrangement.The composition and core-shell structure of ZnO-AS QDs are confirmed by XRD and TEM,and the size of core is calculated to be 6 nm,the size of particle is 20 nm.Furthermore,different colors of ZnO-AS QDs were prepared by adjusting the particle size of ZnO core.更多还原