enhanced-electron-injection-exciton-confinement-for-pure-blue-quantum

Enhanced Electron Injection and Exciton Confinement for Pure Blue Quantum-Dot Light-Emitting Diodes by Introducing Partially Oxidized Aluminum Cathode

Stable and efficient red (R), green (G), and blue (B) light sources based on solution-processed quantum dots (QDs) play important roles in next-generation ...

North China Electric Power University

The film morphology is extremely significant for solution processed perovskite devices. Through fine morphology engineering without using any additives or further posttreatments, a full-coverage and high quantum yield perovskite film has been achieved based on one-step spin-coating method. The morphologies and film characteristics of MAPbBr3 with different MABr:PbBr2 starting material ratios are in-depth investigated by scanning electron microscopy, atomic force microscopy, X-ray diffraction, photoluminescence, and time resolved photoluminescence. High performance organometal halide perovskite light-emitting didoes (PeLEDs) based on simple device structure of indium tin oxide/poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (

Morphology Engineering for High-Performance and Multicolored Perovskite Light-Emitting Diodes with Simple Device Structures.

A new class of hole-transporting materials (HTM) containing tetraphenylmethane (TPM) core have been developed. After thermal, charge carrier mobility, and contact angle tests, it was found that TPA-TPM (TPA: arylamine derivates side group) showed higher glass-transition temperature and larger water-contact angle than spiro-OMeTAD with comparable hole mobility. Photoluminescence and impedance spectroscopy studies indicate that TPA-TPM's hole-extraction ability is comparable to that of spiro-OMeTAD. SEM and AFM results suggest that TPA-TPM has a smooth surface. When TPA-TPM is used in mesoscopic perovskite solar cells, power conversion efficiency comparable to that of spiro-OMeTAD is achieved. Notably, the perovskite solar cells employing TPA-TPM show better long-term stability than that of spiro-OMeTAD. Moreover, TPA-TPM can be prepared from relatively inexpensive raw materials with a facile synthetic route. The results demonstrate that TPM-arylamines are a new class of HTMs for efficient and stable perovskite solar cells.

Tetraphenylmethane-Arylamine Hole-Transporting Materials for Perovskite Solar Cells.

In PIN-type perovskite solar cells (PSCs), the hydroscopicity and acidity of the poly(3,4-ethylenedioxythiophene)-poly(styrene-sulfonate) (PEDOT:PSS) hole transport layer (HTL) have critical influences on the device stability. To eliminate these problems, Nafion, the hydrophobic perfluorosulfonic copolymer, is incorporated into PEDOT:PSS by a simple spin-coating process. For the modified film, Nafion/PSSH (poly(styrene sulfonate) acid) acts as an electron-blocking layer on the surface and the PEDOT-rich domain tends to gather into larger particles with better interchain charge transfer inside the film. Consequently, the modified PEDOT:PSS HTL shows enhanced conductivity and light transmittance as well as more favorable work function, ending up with the increased short-circuit current density (J) and open-circuit voltage (V) of the device. Finally, PSCs with Nafion-modified HTLs achieve the best power conversion efficiency of 16.72%, with 23.76% improvement compared with PEDOT:PSS-only devices (13.51%). Most importantly, the device stability is obviously enhanced because of the hydrophobicity and chemical and mechanical stability of the Nafion polymer that is enriched on the surface of the PEDOT:PSS film.

Article	Year
Morphology Engineering for High-Performance and Multicolored Perovskite Light-Emitting Diodes with Simple Device Structures. Small (Weinheim an der Bergstrasse, Germany)\| PubMed ID: 27392198	2016
Tetraphenylmethane-Arylamine Hole-Transporting Materials for Perovskite Solar Cells. ChemSusChem\| PubMed ID: 27976519	2017
Optical-Electrical-Chemical Engineering of PEDOT:PSS by Incorporation of Hydrophobic Nafion for Efficient and Stable Perovskite Solar Cells. ACS applied materials & interfaces\| PubMed ID: 29308652	2018

Tai Cheng

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