稀土元素Er掺杂的MoSe_(2)垂直纳米线的光致发光性能研究

Investigation of the enhanced photoluminescence properties of MoSe_(2) vertically aligned nanowires using Er3+doping

采用热蒸发法制备了稀土元素铒(Er)掺杂的垂直排列硒化钼(MoSe_(2))纳米线,并研究了稀土元素对硒化钼纳米线的结构、形貌和光电特性的影响。研究发现,Er掺杂后MoSe_(2)纳米线的成核密度和结晶度显著提高,纳米线长度从未掺杂的5 nm增加到8 nm,增加了60%。同时,与未掺杂纳米线相比,掺杂纳米线在可见光波段的光吸收率也提高了50%。此外,MoSe_(2)纳米线室温下在760 nm处发射红光,掺杂后其光致发光强度比未掺杂MoSe_(2)纳米线提高了两个数量级。更重要的是,发现掺杂纳米线在595 nm和675 nm处增加了2个发光峰,分别对应黄绿光和橙红光,主要来源于稀土元素Er^(3+)的复合发光。以上结果表明,Er^(3+)离子在纳米线中起到了活性激发中心的作用,提高了纳米线的发光强度,丰富了MoSe_(2)的发射光谱,可用于制备高效发光和光响应器件。

Erbium(Er)-doped vertically aligned molybdenum selenide(MoSe_(2))nanowires were prepared by thermal evaporation method.The effects of rare earth elements on the structure,morphology and photoelectric properties of MoSe_(2) nanowires were studied.It is found that the nucleation density and crystallinity of MoSe_(2) nanowire are significantly increased after Er^(3+)doping,and the length of the nanowire increases by 60%from 5 nm to 8 nm.Compared with the undoped nanowires,the optical absorption rate of the doped nanowires in the visible band is also increased by 50%.In addition,MoSe_(2) nanowires emit red light at 760 nm at room temperature,and the photoluminescence intensity of doped MoSe_(2) nanowires is two orders of magnitude higher than that of undoped MoSe_(2) nanowires.More importantly,two emission peaks were found at 595 nm and 675 nm,corresponding to yellow-green light and orange-red light respectively,which were mainly derived from the composite emission of rare earth element Er^(3+).The above results indicate that Er^(3+)ions play an active role in the nanowire,which improves the luminescence intensity of the nanowire and enriches the emission spectrum of MoSe_(2),making it suitable for the preparation of efficient luminescence and photoresponse devices.