Abstract

MgAl₂O₄:M (M = Ti, Mn, Co, Ni) phosphors were successfully prepared by a modified polyacrylamide gel method. Calcination temperature and metal particle has significant effects on the phase transition, optical and color properties of Mg Al₂O₄: M phosphors. Ti, M n, Co and Ni metal particles introduced into the MgAl₂O₄ system can produce a variety of colours from white, grayish black, blue to turquoise blue. Mn, Co and Ni metal particles added into MgAl2O4 system can extend their light absorption to visible light range, while the Ti metal particles clad into the system did not improve significantly. Co metal particles appended into the MgAl2O4 system can cause fluorescence quenching of emission peak at 395 nm and enhancement of emission peak at 405 nm, while the Ti and Mn metal particles infused into the system can bring the enhancement of visible emission peak at 425 nm. The fluorescence quenching of the peak at 395 nm can be ascribed to the wavelength of Co metal particles matching the surface plasmon absorbance band of MgAl₂O₄:M phosphor. A reduction in emission intensity at 425 nm can be assigned to electron transfer from the conduction band (CB) of MgAl₂O₄ to the CB of metal particles causing non-radiative decay.

摘要

通过改性聚丙烯酰胺凝胶法成功制备了MgAl ₂ O ₄：M（M = Ti，Mn，Co，Ni）荧光粉。煅烧温度和金属颗粒对Mg Al ₂ O ₄：M磷光体的相变，光学和颜色性质有重要影响。引入MgAl ₂ O _4的Ti，Mn，Co和Ni金属颗粒该系统可以产生从白色，灰黑色，蓝色到蓝绿色的各种颜色。添加到MgAl2O4系统中的Mn，Co和Ni金属粒子可以将其光吸收范围扩展到可见光范围，而包覆在系统中的Ti金属粒子并没有明显改善。掺入MgAl2O4系统中的Co金属粒子可导致395 nm处发射峰的荧光猝灭和405 nm处的发射峰的增强，而注入系统中的Ti和Mn金属粒子可引起425 nm处的可见发射峰的增强。395 nm峰的荧光猝灭可以归因于与MgAl ₂ O ₄的表面等离激元吸收带相匹配的Co金属颗粒的波长：M磷 425 nm处发射强度的降低可以归因于电子从MgAl ₂ O ₄的导带（CB）转移到金属粒子的CB，从而引起非辐射衰减。