在先前的研究中，我們提出一個有效提升鈣鈦礦發光二極體的改善方法，以綠光材料CH3NH3PbBr3為例，使用甲胺氣體修飾鈣鈦礦薄膜所製作出的有機鈣鈦礦發光二極體元件，其最大亮度可達70,000 cd/m2且發光效率可達15 cd/A。然而，元件的亮度-電流密度曲線卻顯示不正常的非線性趨勢，這項結果指出鈣鈦礦晶體薄膜界面間高濃度的缺陷態，仍是決定元件效率的關鍵所在。所以，藉由摻雜相反電荷離子的方法去鈍化晶體界面的缺陷態，我們可以大幅地提升鈣鈦礦發光二極體元件於低電流密度下的亮度和發光效率，此外，元件的亮度-電流密度曲線亦可回復到有機發光二極體元件的線性趨勢。
　　元件結構為Glass / ITO / NiOx / 摻雜溴化鉀(KBr)或氯化膽鹼(Choline chloride)之CH3NH3PbBr3 / TPBi / LiF / Al。鈣鈦礦發光二極體在電流密度為10 mA/cm2時，摻雜溴化鉀的元件，其亮度、發光效率和未摻雜的元件相比下，有6倍的提升；而摻雜氯化膽鹼的元件，則有10倍以上的提升。

In the previous study, we presented the efficient methylammonium lead bromide (CH3NH3PbBr3)-based hybrid light-emitting diodes (LED) by the modification of perovskite films with methylamine gas, the maximum brightness >70,000 cd/m2 and the luminous efficiency (LE) >15 cd/A. However, the luminance-current density curve of device shows an abnormal non-linear trend. This result indicates that the high concentration of traps in the interface of perovskite crystal film is still the key to determining the performance of the device. Therefore, we can greatly improve the brightness and luminous efficiency of the perovskite light-emitting diode at low current density by doping the opposite charge ion to passivate the trap states of the crystal interface. In addition, the luminance-current density curve of the device can also be reverted to the linear trend like the organic light-emitting diode.
The device structure is glass/indium-tin-oxide/NiOx/CH3NH3PbBr3/TPBi/LiF/Al, the perovskite film doped with potassium bromide (KBr) or choline chloride. Perovskite light-emitting diodes doped with potassium bromide at a current density of 10 mA/cm2, exhibit 6-fold increase in brightness and LE as compared to those of the controlled cell without doping potassium bromide. The devices doped with choline chloride at a current density of 10 mA/cm2, exhibit 10-fold increase in brightness and LE as compared to those of the controlled cell without doping choline chloride.

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