Cs_(0.05)FA_(0.79)MA_(0.16)PbI_(2.52)Br_(0.48)钙钛矿薄膜的变温光致发光特性  

Temperature-dependent Photoluminescence Properties of Cs_(0.05)FA_(0.79)MA_(0.16)PbI_(2.52)Br_(0.48)Perovskite Thin Film

作　　者：张琼 吴悦嘉 冯艳琴 孙立伟 戴俊 ZHANG Qiong;WU Yue-jia;FENG Yan-qin;SUN Li-wei;DAI Jun(School of Science,Jiangsu University of Science and Technology,Zhenjiang 212100,China)

机构地区：[1]江苏科技大学理学院,江苏镇江212100

出　　处：《发光学报》2021年第9期1396-1402,共7页Chinese Journal of Luminescence

基　　金：国家自然科学基金(11874185)资助项目。

摘　　要：报道了Cs_(0.05)FA_(0.79)MA_(0.16)PbI_(2.52)Br_(0.48)钙钛矿薄膜的变温光致发光特性。采用一步旋涂法,用氯苯作反溶剂制备了Cs_(0.05)FA_(0.79)MA_(0.16)PbI_(2.52)Br_(0.48)钙钛矿薄膜,并对其表面形貌和结晶质量进行了表征。X射线衍射(XRD)分析结果表明其为四方钙钛矿结构。钙钛矿薄膜表面均匀致密,晶粒尺寸约为300 nm。在5~200 K温度范围内测量了光致发光强度,结果表明,光致发光光谱连续蓝移约9.36 nm,没有相变引起的反转红移。光致发光强度随温度的升高呈双指数降低,由Arrhenius方程拟合得到了两个热激活能。通过玻色-爱因斯坦双谐振子模型对光学带隙进行了拟合,并对非重整化带隙能量、声学声子能量和光学声子能量也进行了拟合。通过Segall公式拟合光致发光的半峰宽(FWHM),研究了激子-声子相互作用对光致发光展宽的影响。在10 K和100 K时,光致发光主要来自激子复合;而在200 K时,辐射复合主要来自自由-束缚对和施主-受主对,这意味着缺陷相关的光致发光是在高温下产生的。本文详细的光学参数可以为钙钛矿型光电器件的研究提供物理基础。This paper reports the temperature-dependent photoluminescence properties of Cs_(0.05)FA_(0.79)MA_(0.16)PbI_(2.52)Br_(0.48)perovskite thin film.The Cs_(0.05)FA_(0.79)MA_(0.16)PbI_(2.52)Br_(0.48)perovskite thin film was prepared by one-step spin coating with chlorobenzene anti-solvent treatment,and the surface morphology and crystallization quality were characterized.The X-ray diffraction(XRD)indicates that the Cs_(0.05)FA_(0.79)MA_(0.16)PbI_(2.52)Br_(0.48)has a typical tetragonal perovskite structure.The perovskite film has a uniform and dense surface,and the grain size is about 300 nm.The photoluminescence intensity was measured in the temperature range of 5-200 K.The photoluminescence spectra show a continuous blue shift of about 9.36 nm,and there is no reversal redshift induced by phase transition.The photoluminescence intensity shows a bi-exponential quenching with the increase of temperature,and two thermal activation energies are obtained by Arrhenius equation.The optical bandgap is fitted by the Bose-Einstein double harmonic oscillator model,and the non-renormalized bandgap energy,the energies of acoustic phonon and optical phonon were fitted.The photoluminescence broadening mechanism was studied by the Segall formula.At 10 K and 100 K,the photoluminescence is mainly from exciton recombination,while at 200 K,the radiation recombination is mainly from free-to-bound and donor-acceptor pairs,which means the defect associated photoluminescence arises at high temperature.The detailed optical parameters in our paper can provide a physical foundation for further optimization of perovskite optoelectronic devices.

关 键 词：钙钛矿薄膜 变温光致发光 激子-声子相互作用 

分 类 号：O482.31[理学—固体物理]