稀土镥离子掺杂甲胺氯化铅钙钛矿单晶的生长与表征

Growth and characterization of rare earth lutetium ion doped methylamine lead chloride perovskite single crystal

近年来,卤化铅钙钛矿由于其光电性能优异,在光伏电池、光电传感器、发光二极管等领域展现了广泛应用,成为了材料领域的研究热点。稀土掺杂被证实可以调节钙钛矿多晶薄膜和纳米晶的半导体光电性能,但稀土离子掺杂单晶报道较少。这里,我们利用逆温结晶法合成了稀土镥离子掺杂甲胺氯化铅钙钛矿单晶。粉末X射线衍射证明镥离子掺杂甲胺氯化铅钙钛矿单晶高的结晶度,稀土掺杂导致衍射峰向高角度偏移了0.02度。X射线光电子能谱结果表明稀土Lu离子掺杂后,观察到来自Lu元素的谱峰,Pb2+4f的峰值向低能量方向移动,说明稀土镥离子进入到了晶格。通过紫外可见漫反射光谱以及X射线光电子能谱表征其带隙宽度、导带底和价带顶,表明稀土Lu掺杂可以调节甲胺氯化铅钙钛矿单晶的半导体能带。

In recent years,lead perovskite halide has been widely used in the fields of photovoltaic cell,photoelectric sensor and light-emitting diode because of its excellent photoelectric properties.It has been proved that rare earth doping can adjust the photoelectric properties of perovskite polycrystalline films and nanocrystals,but the rare earth ion doped single crystals are rarely reported.Here,we have synthesized rare earth lutetium ion doped methylamine lead chloride perovskite single crystal by inverse temperature crystallization method.The powder X-ray diffraction results show that the crystallinity of lutetium ion doped lead perovskite with methylamine chloride is high,and the diffraction peak is shifted 0.02 degree to high angle by rare earth doping.X-ray photoelectron spectroscopy shows the presence of spectral peaks from lutetium and that the peak value of Pb2+4f moves towards the low energy direction after doping with rare earth lutetium ion,which indicates that lutetium ions enter the crystal lattice.The band gap,the conduction-band-minimum and the valance-band-maximum were characterized by UV-Vis diffuse reflectance spectroscopy and X-ray photoelectron spectroscopy.