【摘要】 利用溶胶凝胶法,通过直接掺杂Mn2+获得白光发射且操作工艺简单的纳米ZnS∶Mn荧光粉,使用XRD、UV、PL及FT IR等方法研究了ZnS∶Mn纳米微粒的粒径、结构及荧光特性。结果表明:ZnS∶Mn纳米微粒的平均粒径约为7nm,为闪锌矿晶体结构;所制备样品的荧光发射光谱有强度相当的两个峰,一个是峰值位于480nm的基质发光,另一个是峰值位于590nm的橙色光,样品总体发白光;Mn2+的掺杂量对ZnS∶Mn纳米白光荧光粉发光性能的影响很大;在纳米微粒的形成过程中,聚甲基丙烯酸将该纳米粒子包覆。更多还原

【Abstract】 As an important ⅡⅥ group material, ZnS nanoparticles have attracted more interest in its novel photoelectric properties, such as its wide bandgap and high luminescent efficiency. And in the last years scholars have composed all kinds of light-emitting ZnS based nano-phosphor powder. Recently the white-light emitting EL devices are mainly made by two methods. One type of device is structured by red-light, green-light and blue-light emitting diodes. The other type is achieved by transforming two or three kinds of colors coming from different fluorescent powders. But there lacks a type of ZnS based nano-phosphor powder which emitting white-light all by itself. The white-light emitting ZnS based nanoparticles have been prepared by doping the Mn 2+ directly into the ZnS nanoparticles, which suggests a simple and easy operation. In the operation we mainly controlled two factors. One is the reactive temperature, and the other is the doping ration of the Mn 2+ in the ZnS nanoparticles. The prepared particles are as small as 7 nm in diameter with consistent crystal structure and mono-dispersivity and capped or modified by methacrylic polymer. The photoluminescence (PL) spectra of the ZnS∶Mn nanopowder exhibit two emission peaks under excitation of 380 nm, one is at 480 nm with an blue-light emitting coming from the ZnS base and the other is at 590 nm with a yellow-light emitting coming from the Mn 2+ dopant. In general, the two violent emitting come into being an white-light emitting. It is worthy to give a careful discussion about the doping ration of the Mn 2+ in the ZnS nanoparticles because only the optimum dose can make the ZnS∶Mn nanopowder to exhibit white-light emitting. X-ray diffraction (XRD) demonstrated that the ZnS∶Mn nanoparticles have zinc blend crystal structure and Scherrer formulation was applied to estimate the diameter of the ZnS∶Mn nanoparticles,which is about 7~8 nm. In its UV-vis spectra, there is a blue shift of the absorption peak due to the modified surface and small size effect of the ZnS∶Mn nanoparticles. According to the blue shift, Brus formulation was applied to estimate the diameter of the nanoparticles, which is consistent with the result obtained from the Scherrer formulation. The IR patterns of the ZnS∶Mn nanoparticles and the one of the methacrylic acid have much comparability indicating that methacrylic polymer has capped or modified the ZnS∶Mn nanoparticles.更多还原