Bright Visible-Infrared Light Emitting Diodes Based on Hybrid Halide Perovskite with Spiro-OMeTAD as a Hole-Injecting Layer

Abstract

Hybrid halide perovskites that are currently intensively studied for photovoltaic applications, also present outstanding properties for light emission. Here, we report on the preparation of bright solid state light emitting diodes (LEDs) based on a solution-processed hybrid lead halide perovskite (Pe). In particular, we have utilized the perovskite generally described with the formula CH 3 NH 3 PbI 3-x Cl x and exploited a configuration without electron or hole blocking layer in addition to the injecting layers. Compact TiO 2 and Spiro-OMeTAD were used as electron and hole injecting layers, respectively. We have demonstrated a bright combined visible-infrared radiance of 7.1 W• sr −1 •m −2 at a current density of 232 mA•cm −2 , and a maximum external quantum efficiency (EQE) of 0.48%. The devices prepared surpass the EQE values achieved in previous reports, considering devices with just an injecting layer without any additional blocking layer. Significantly, the maximum EQE value of our devices is obtained at applied voltages as low as 2 V, with a turn-on voltage as low as the Pe band gap (V turn-on = 1.45 ± 0.06 V). This outstanding performance, despite the simplicity of the approach, highlights the enormous potentiality of Pe-LEDs. In addition, we present a stability study of unsealed Pe-LEDs, which demonstrates a dramatic influence of the measurement atmosphere on the performance of the devices. The decrease of the electroluminescence (EL) under continuous operation can be attributed to an increase of the nonradiative recombination pathways, rather than a degradation of the perovskite material itself.

Light-induced effects on Spiro-OMeTAD films and hybrid lead halide perovskite solar cells

“…Therefore, it is expected that a complete device will suffer a similar photo-induced evolution in the working conditions, thus making difficult a precise control of the Spiro doping level. In fact, a related phenomenon has been recently reported for PS based LEDs, where an initial partial oxidation of the Spiro film provokes an enhancement of the device performance; however after reaching an oxidation threshold, the performance starts dropping dramatically [24]. Therefore, such oxidation has direct consequences on the device functioning and stability.…”

Hybrid Perovskites: Effective Crystal Growth for Optoelectronic Applications

“…[141] Copyright 2016, Wiley. [178] thin film ITO/PEDOT:PSS/MAPbBr3/ZnO/Ca/Ag 21 -550 2 -- [179] thin film ITO/Buf-HIL/MAPbBr3/TPBi/LiF/Al 0.577 0.125 417 4 543 20 [60] thin film ITO/c-TiO2/EA/MAPbBr3/SPB-02T/MoO3/Au 0.22 0.051 544 ~2.3 -- [27] thin film ITO/ZnO-PEI/MAPbBr3/TFB/MoO3/Au -0.8 20000 2.8 532 22 [180] thin film ITO/ZnO-PEI/MAPbI3-nCln/TFB/MoOx/Au -3.5 28* 2.2 768 37 [180] Polymer blending thin film ITO/MAPbBr3-PEO/In/Ga 0.38 0.083 4064 2.9 532 23 [181] thin film ITO/MAPbBr3-PEO/AgNWs 4.91 1.1 21014 2.6 -- [182] thin film ITO/PEDOT:PSS/MAPbBr3-PIP/F8/Ca/Ag -1.2 200 ~3.1 534 19 [183] Solvent treatment thin film ITO/PEDOT:PSS/MAPbBr3/SPB-02T/LiF/Ag 0.43 0.1 3490 ~2.1 540 - [184] thin film ITO/PEDOT:PSS/MAPbBr3/Bphene/LiF/Ag 0.54 0.13 3846 3.2 528 21 [185] thin film Glass/SOCP/MAPbBr3/TPBi/LiF/Al 42.9 8.53 15000 4 -- [14] Inorganic substitution thin film ITO/PEDOT:PSS/CsPbBr3/F8/Ca/Ag 0.035 0.008 407 3 527 18 [186] Nanostructuring nano plate ITO/PEDOT:PSS/MAPbBr3/PVK:PBD/BCP/LiF/Al -0.48 10590 3.8 20 [187] nano plate ITO/PEDOT:PSS/FAPbBr3:LiCF3SO3:TMPE/Al --1.3 11~1 2 -- [188] QD ITO/PEDOT:PSS/PVK/FAPbBr3/TPBI/LiF-Al 0.43 0.12 946 4.2 514 23 [189] QD ITO/PEDOT:PSS/PVK/CsPb(Cl/Br)3 /TPBI/LiF-Al 0.14 0.07 742 5.1 452 20 [189] QD ITO/PEDOT:PSS/PVK/CsPb(Br/I)3/TPBI/LiF-Al 0.08 0.09 528 4.6 586 23 [189] thin film ITO/PEDOT:PSS/CsPbBr3/B3PYMPM/CsCO3/Al 0.57 0.15 7276 2.8 524 18 [190] nano particle ITO/PEDOT:PSS/Poly-TPD:PFI/CsPbBr3/TPBi/LiF/Al 0.19 0.06 1377 3.5 516 18 [13] nano particle ITO/ZnO/CsPbBr3/TFB/MoO3/Ag 0.28 0.19 2335 2.8 523 19 [47] nano particle ITO/ZnO/CsPbI3/TFB/MoO3/Ag -5.7 206 -698 31 [47] nano particle ITO/ZnO/CsPbI3-nBrn/TFB/MoO3/Ag -1.4 1559 -619 29 [47] nano particle ITO/ZnO/CsPbBrnCln/TFB/MoO3/Ag -0.0074 8.7 -480 17 [47] Low dimension thin film ITO/TIO2/PEA2MAn-1PbnI3n+1/F8/MoO3/Au -8.8 80* 3.8 [16] thin film ITO/PEDOT:PSS/poly-TPD/BA2MA2Pb3I10/TPBi/LiF/Al 0.1 2.29 214 2.7 700 52 [191] thin film ITO/PEDOT:PSS/poly-TPD/BA2MA4Pb5Br16/TPBi/LiF/Al 3.48 1.01 2246 3.3 523 24 …”

Research Update: Challenges for high-efficiency hybrid lead-halide perovskite LEDs and the path towards electrically pumped lasing

“…The earliest report by Tan et al attributes the device degradation and efficiency roll-off to a heating effect at high current density. 10 Jaramillo-Quintero et al investigated the mechanism of PeLED degradation 23 and found an increase in non-radiative recombination under oxygen/ambient conditions. More recently, Yu et al found that annealing the CH 3 NH 3 PbBr 3 film at 60…”

“…Most reports of PeLEDs used a 3D-structured CH 3 NH 3 PbX 3 perovskite. 10,20,[23][24][25][26][27] Lower-dimensional perovskites have drawn researchers' attention recently. 21,28,29 Apart from using organic anions, several more recent reports employed Csbased all-inorganic halide perovskites to make use of their better thermal stability.…”