Evaluating The Performance Of a Single-Layer Blue Light-Emitting - - PowerPoint PPT Presentation

• S. Anoshkin,1 A. Pushkarev,1 A. Zakhidov,1, 2 and S. Makarov1

Evaluating The Performance Of a Single-Layer Blue Light-Emitting Electrochemical Cell Based on a Perovskite-Polymer Composite

1 Department of Physics and Engineering, ITMO University, St. Petersburg 197101, Russia 2 University of Texas at Dallas, Richardson, TX 75080, USA

Introduction Theory Fabrication Results Conclusion

Herein, we present the engineering of a blue pero-LEC based on inorganic perovskite-polymer composite which operates within the electrochemical doping model. We analyze the device performance to derive its crucial physical parameters and suggest a way towards its efficient and long-term operation. Most of the planar light-emitting devices have a multilayer structure that consists

• f electron-transporting (ETL), hole-transporting (HTL), and emissive (EL) layers.

Usually, the manufacturing of the devices with a complex architecture is related to the employment of expensive materials and high-tech processes such as vacuum deposition. Therefore, cost effective and largescale wet chemical production of efficient single-layer light-emitting devices remains a hot topic in the field of optoelectronics. This work was supported by the Russian Science Foundation (project no. 19-73-30023).

Introduction Theory Fabrication Results Conclusion References [1] Chem. Soc. Rev., 2018, 47. p. 7045 [2] Nano Lett., 2015, 15 , pp 3692 [3] PNAS, 2016, 113, 11694

Lead halide perovskites

• Room-temperature excitonic emission with high quantum yield
• Spectral linewidth of 14-30 nm
• Efficient light output and high color purity
• Cost-effective and largescale wet chemical production
• S. Anoshkin,1 A. Pushkarev,1 A. Zakhidov,1, 2 and S. Makarov1

Evaluating The Performance Of a Single-Layer Blue Light-Emitting Electrochemical Cell Based on a Perovskite-Polymer Composite

Introduction Theory Fabrication Results Conclusion

Pero-LEC fabrication process

• S. Anoshkin,1 A. Pushkarev,1 A. Zakhidov,1, 2 and S. Makarov1

Evaluating The Performance Of a Single-Layer Blue Light-Emitting Electrochemical Cell Based on a Perovskite-Polymer Composite

Perovskite-polymer ink spin-casting Annealing Vacuum drying

500 nm glass ITO CsPbCl1.12Br1.88Cs4PbCl3.04Br2.96 (8:1)-PEO 1 μm

Cross-section (left) and top-view (right) SEM images of CsPbCl1.12Br1.88Cs4PbCl3.04Br2.96 (8:1)-PEO film on ITO substrate Schematically represented pero-LEC structure Fabricated pero-LEC

Introduction Theory Fabrication Results Conclusion

Fabricated pero-LECs Characteristics

• S. Anoshkin,1 A. Pushkarev,1 A. Zakhidov,1, 2 and S. Makarov1

Evaluating The Performance Of a Single-Layer Blue Light-Emitting Electrochemical Cell Based on a Perovskite-Polymer Composite

1 2 3 4 0.01 0.1 1 10 100 1000

Voltage (V) Current density (mA/cm

2)

0.1 1 10 100 1000 10000

Brightness (cd/m

2)

J–V and L–V characteristics of the fabricated pero-LEC Fabricated pero-LEC EL spectra of the fabricated pero-LEC

• λEL = 478 nm, FWHM = 14 nm, L = 217 cd/m2 (under 3.2 V forward bias)
• VON = 2.6 V

Introduction Theory Fabrication Results Conclusion

Ohmic region of Current-Voltage Characteristic J–V and L–V characteristics of the fabricated pero-LEC

1 2 3 4 0.01 0.1 1 10 100 1000

Voltage (V) Current density (mA/cm

2)

0.1 1 10 100 1000 10000

Brightness (cd/m

2)

• S. Anoshkin,1 A. Pushkarev,1 A. Zakhidov,1, 2 and S. Makarov1

Evaluating The Performance Of a Single-Layer Blue Light-Emitting Electrochemical Cell Based on a Perovskite-Polymer Composite

𝑘 ∝ 𝑊

Introduction Theory Fabrication Results Conclusion

Shockley region of Current-Voltage Characteristic J–V and L–V characteristics of the fabricated pero-LEC

1 2 3 4 0.01 0.1 1 10 100 1000

Voltage (V) Current density (mA/cm

2)

0.1 1 10 100 1000 10000

Brightness (cd/m

2)

• S. Anoshkin,1 A. Pushkarev,1 A. Zakhidov,1, 2 and S. Makarov1

Evaluating The Performance Of a Single-Layer Blue Light-Emitting Electrochemical Cell Based on a Perovskite-Polymer Composite

𝑘 𝑊 = 𝑘0 exp 𝑟𝑊 𝜃𝑙𝑈 − 1

Fitting parameters: 𝑙𝑈 = 0,025 eV 𝑘0 = 1.83*10-4 mA/cm2 𝜃 = 9.77

Introduction Theory Fabrication Results Conclusion

Saturation region of Current-Voltage Characteristic J–V and L–V characteristics of the fabricated pero-LEC

1 2 3 4 0.01 0.1 1 10 100 1000

Voltage (V) Current density (mA/cm

2)

0.1 1 10 100 1000 10000

Brightness (cd/m

2)

• S. Anoshkin,1 A. Pushkarev,1 A. Zakhidov,1, 2 and S. Makarov1

Evaluating The Performance Of a Single-Layer Blue Light-Emitting Electrochemical Cell Based on a Perovskite-Polymer Composite

𝑘 = 9 8 𝜁𝑠𝜁0𝜈 𝑊 − 𝑊

𝑐𝑗 2

𝑒3

Fitting parameters: 𝜁𝑠 = 20 (literature) 𝑊

𝑐𝑗 = 2.36 eV

d = 300 nm 𝜈 = 1.4 m2/V*s

Introduction Theory Fabrication Results Conclusion

• 1. A new approach to simple fabrication of single-layer blue pero-LECs based on perovskite-polymer thin film is
• developed. The device demonstrates low turn-on voltage of 2.6 V and relatively bright (217 cd/m2) narrowband

electroluminescence at 478 nm under 3.2 V forward bias.

• 2. Numerous structural defects generated during its operation dramatically affects electron-hole radiative

recombination, in particular, a very large ideality factor (h=9.77) of the Shockley-Read-Hall behavior and relatively low charge carrier mobility m = 1.4 cm2/Vs are established. In this context, single-layer pero-LECs operating within electrochemical doping (ECD) model do not seem prospective devices for the development of the next-generation display technology.

• 3. Substantial improvement of pero-LECs electroluminescence, however, could be proposed for the devices operating

within the electrodynamic (ED) model. The latter requires adding of salts producing high-mobility ions for rapid formation of a p-i-n junction and hence providing the intrinsic perovskite layer with a free field region. sergey.anoshkin@metalab.ifmo.ru

• S. Anoshkin,1 A. Pushkarev,1 A. Zakhidov,1, 2 and S. Makarov1

Evaluating The Performance Of a Single-Layer Blue Light-Emitting Electrochemical Cell Based on a Perovskite-Polymer Composite

1 Department of Physics and Engineering, ITMO University, St. Petersburg 197101, Russia 2 University of Texas at Dallas, Richardson, TX 75080, USA