Mn^(2+)掺杂准二维钙钛矿(PEA)_(2)Pb_(y)Mn_(1-y)Br_(4)的制备及其电致发光性能

Synthesis and electroluminescence properties of Mn^(2+)doped quasi-two-dimensional perovskites(PEA)_(2)Pb_(y)Mn_(1-y)Br_(4)

制备了具有高荧光量子产率(photoluminescence quantum yield,PLQY)的Mn^(2+)掺杂准二维钙钛矿(PEA)_(2)Pb_(y)Mn_(1-y)Br_(4)(PEA为苯乙胺,y为Pb^(2+)占Mn^(2+)和Pb^(2+)总含量的物质的量分数)薄膜。宽带隙的(PEA)_(2)PbBr_(4)作为给体,掺杂杂质Mn^(2+)作为受体,构筑了双发射的激发态传递系统。通过调控Mn^(2+)掺杂的不同比例对(PEA)_(2)Pb_(y)Mn_(1-y)Br_(4)的发光性能和薄膜形貌的影响,发现当前驱体溶液中Mn^(2+)与Pb^(2+)的物质的量之比为1∶4时,薄膜有着最高的PLQY和最低的表面粗糙度。利用飞秒瞬态吸收(transient absorption,TA)光谱,追踪其动力学过程,发现主客体之间的激发态传递是通过电荷转移来实现的。为了研究材料的电致发光特性,我们将(PEA)_(2)Pb_(y)Mn_(1-y)Br_(4)作为活性层,加工得到了发光二极管(light emitting diodes,LEDs)。在室温下,器件发出明亮的橙色,其最高的发光强度为0.21 cd·m^(-2),外量子效率(external quantum efficiency,EQE)为0.0025%。

Mn^(2+)-doped quasi-two-dimensional perovskite(PEA)_(2)Pb_(y)Mn_(1-y)Br_(4)(PEA is phenylethylamine,y is the frac-tion of Pb^(2+)in the total content of Mn^(2+)and Pb^(2+))thin films were prepared successfully with high photoluminescence quantum yield(PLQY).It constructed a dual-emissive excited state transfer system,while(PEA)_(2)PbBr_(4)and impurity Mn^(2+)respectively act as the donor and acceptor.Mn^(2+)incorporation improved the luminescence properties and film morphologies.Using the femtosecond transient absorption(TA)measurement,we demonstrated the charge transfer processes between the host and the guest.To study the electroluminescence properties,(PEA)_(2)Pb_(y)Mn_(1-y)Br_(4)film was employed as the active layer to fabricate LED(light emitting diodes,LEDs)devices.The(PEA)_(2)Pb_(y)Mn_(1-y)Br_(4)LED device emitted a bright orange color,which demonstrated a maximum luminous intensity of 0.21 cd·m^(-2)with an external quantum efficiency(EQE)of 0.0025%.