System And Methods For Improving The Qualities Of Polymer Light-Emitting Electrochemical Cells,
2014
The University of Akron
System And Methods For Improving The Qualities Of Polymer Light-Emitting Electrochemical Cells, Xiong Gong
Xiong Gong
A light-emitting device comprising a pair of electrodes, and an emitting polymer active layer between the pair of electrodes, and either a) an electron transport layer, b) a hole transport layer, or c) a low work function material layer, wherein said emitting polymer layer comprising a single phase combination of a light-emitting polymer and an ionic liquid, is provided. Such multilayered devices have increased stability at relatively high voltages, fast turn-on times, low operating voltage, high brightness and long lifetimes.
Enhanced Electron Injection In Polymer Light-Emitting Diodes: Polyhedral Oligomeric Silsesquioxanes As Dilute Additives,
2014
The University of Akron
Enhanced Electron Injection In Polymer Light-Emitting Diodes: Polyhedral Oligomeric Silsesquioxanes As Dilute Additives, Xiong Gong
Xiong Gong
By blending monochlorocyclohexyl- polyhedral oligomeric silsesquioxanes (MCC-POSS) into poly(2-methoxy-5-(2'-ethyl-hexyloxy)-1.4-phenylenevinylene (MEH-PPV), enhanced luminous efficiency (LE, cd A−1) and brightness were observed in polymer light-emitting diodes (PLEDs) using Al as the cathode. PLEDs made from MEH-PPV with 0.5 wt.% of MCC-POSS exhibit LE of 1 cd A−1, four times higher than that observed in simple MEH-PPV devices. x-ray diffraction studies, measurements of photovoltaic response and measurements of photoconductivity from the films of pure MEH-PPV and MEH-PPV with MCC-POSS demonstrated that the improved device performance results from mixing of MCC-POSS with MEH-PPV. The enhanced electron-injection into the emissive layer results from the effect …
Strain And Huckel Aromaticity: Driving Forces For A Promising New Generation Of Electron Acceptors In Organic Electronics,
2014
The University of Akron
Strain And Huckel Aromaticity: Driving Forces For A Promising New Generation Of Electron Acceptors In Organic Electronics, Xiong Gong
Xiong Gong
Straining at the leash: The main features of electron-accepting materials with a 9,9′-bifluorenylidene backbone are strain relief and a gain in aromaticity. These dimers (see picture) exhibit absorption near the red spectral region (ca. 600 nm) and HOMO (5.58–5.06 eV) and LUMO (3.37–3.09 eV) energy levels, which, together with high solubility and thermal stability render these materials attractive acceptors for bulk heterojunction (BHJ) solar cells.
Biosensors From Conjugated Polyelectrolyte Complexes,
2014
The University of Akron
Biosensors From Conjugated Polyelectrolyte Complexes, Xiong Gong
Xiong Gong
n this paper, we report an investigation of the PL from a conjugated polyelectrolyte complex in aqueous solution. We show that the anionic conjugated polymer alone is subject to nonspecific effects on the PL (luminescence enhancement), which complicates the use of conjugated polyelectrolytes in biosensing applications. We find, however, that when a cationic polymer is added in the solution to associate with the anionic conjugated polyelectrolyte and form a charge neutral complex (CNC) [formed in aqueous solution by an anionic conjugated polyelectrolyte and a saturated cationic polyelectrolyte at a 1:1 ratio (per repeat unit)], the CNC shows little evidence of …
High Performance Polymer Light-Emitting Diodes Fabricated With A Novel Hole Injection Layer,
2014
The University of Akron
High Performance Polymer Light-Emitting Diodes Fabricated With A Novel Hole Injection Layer, Xiong Gong
Xiong Gong
Enhanced luminance (L) and luminous efficiency (LE) of polymer light-emitting diodes (PLEDs) is demonstrated using poly (bis (tetraphenyldiamino)biphenyl-perfluorocyclobutane), poly(BTPD-Si-PFCB), as the hole injection layer. The monomer is cast directly onto the indium-tin-oxide anode and thermally polymerized in situ. Hole injection from poly(BTPD-Si-PFCB) into the Â"super yellowÂ" derivative of poly(phenylene vinylene) and into several blue emitting polymers is comparable to or better than that from poly(enthylendioxythiophene):poly(styrene sulfonic acid) (PEDOT:PSSA). With poly(BTPD-Si-PFCB) as the hole injecting layer into super yellow, the performance is identical to that obtained with PEDOT:PSSA (LE » 8 cd/A with little fall-off even at L > 104 cd/m2). For …
Preparation And Photoluminescence Of Nanocrystalline Mso 4: Xtb 3+(M= Ca, Sr, And Ba; X= 0.001--0.005),
2014
The University of Akron
Preparation And Photoluminescence Of Nanocrystalline Mso 4: Xtb 3+(M= Ca, Sr, And Ba; X= 0.001--0.005), Xiong Gong
Xiong Gong
A series of nanocrystalline MSO4:xTb3+ (M=Ca, Sr, and Ba; x=0.001-0.005) samples have been prepared by the co-precipitation method following low-temperature treatment. The x-ray diffraction technique yielded an average grain size of approximately 24 nm. Based upon the experimental data and theoretical calculations, it is concluded that the photoluminescence quenching in nanocrystalline MSO4:xTb3+ results from the dipole-quadrupole interaction.
Polymer Solar Cells,
2014
The University of Akron
An Electrochemical Super Sandwich Assay For Sensitive And Selective Dna Detection In Complex Matrices,
2014
The University of Akron
An Electrochemical Super Sandwich Assay For Sensitive And Selective Dna Detection In Complex Matrices, Xiong Gong
Xiong Gong
In a traditional sandwich assay, a DNA target hybridizes to a single copy of the signal probe. Here we employ a modified signal probe containing a methylene blue (a redox moiety) label and a “sticky end.” When a DNA target hybridizes this signal probe, the sticky end remains free to hybridize another target leading to the creation of a supersandwich structure containing multiple labels. This leads to large signal amplification upon monitoring by voltammetry.
Polymer Solar Cells With Larger Open-Circuit Voltage,
2014
The University of Akron
Polymer Solar Cells With Larger Open-Circuit Voltage, Xiong Gong
Xiong Gong
No abstract provided.
A Porphyrin--Fullerene Dyad With A Supramolecular Double-Cable Structure As A Novel Electron Acceptor For Bulk Heterojunction Polymer Solar Cells,
2014
The University Of Akron
A Porphyrin--Fullerene Dyad With A Supramolecular Double-Cable Structure As A Novel Electron Acceptor For Bulk Heterojunction Polymer Solar Cells, Chien-Lung Wang, Wen-Bin Zhang, Ryan Van Horn, Yingfeng Tu, Xiong Gong, Stephen Cheng, Yanming Sun, Minghong Tong, Junghwa Seo, Ben Hsu, Alan Heeger
Xiong Gong
With a supramolecular “double-cable” structure in the solid state, a light harvesting porphyrin-fullerene dyad is demonstrated to be a promising candidate for new electron acceptors in high-performance bulk heterojunction (BHJ) polymer solar cells (PSCs). It has long-lived mobile carriers, a high short circuit current, and a large open circuit voltage.
Organic Photoresponse Materials And Devices,
2014
The University of Akron
Organic Photoresponse Materials And Devices, Huanli Dong, Hongfei Zhu, Qing Meng, Xiong Gong, Wenping Hu
Xiong Gong
Organic photoresponse materials and devices are critically important to organic optoelectronics and energy crises. The activities of photoresponse in organic materials can be summarized in three effects, photoconductive, photovoltaic and optical memory effects. Correspondingly, devices based on the three effects can be divided into (i) photoconductive devices such as photodetectors, photoreceptors, photoswitches and phototransistors, (ii) photovoltaic devices such as organic solar cells, and (iii) optical data storage devices. It is expected that this systematic analysis of photoresponse materials and devices could be a guide for the better understanding of structure–property relationships of organic materials and provide key clues for the …
Solution-Processed Zinc Oxide Thin Film As A Buffer Layer For Polymer Solar Cells With An Inverted Device Structure,
2014
The University of Akron
Solution-Processed Zinc Oxide Thin Film As A Buffer Layer For Polymer Solar Cells With An Inverted Device Structure, Xiong Gong
Xiong Gong
A solution-processed zinc oxide (ZnO) thin film as a buffer layer for polymer solar cells (PSCs) with an inverted device structure has been demonstrated. A power conversion efficiency (PCE) of 3.8% was observed from an inverted device structure with the ZnO buffer layer. Without the ZnO layer, PSCs only show a PCE of 1.67%, which is less than half the value observed from PSCs with the ZnO buffer layer. When operated at room temperature, no obvious degradation was observed from the PSCs with the ZnO layer after continuously illuminating the devices for 4 h. However, a significant degradation was observed …
Polymer Solar Cells By Novel Electron Acceptor,
2014
The University of Akron
Polymer Solar Cells By Novel Electron Acceptor, Xiong Gong
Xiong Gong
No abstract provided.
On The Binding Of Cationic, Water-Soluble Conjugated Polymers To Dna: Electrostatic And Hydrophobic Interactions,
2014
The University of Akron
On The Binding Of Cationic, Water-Soluble Conjugated Polymers To Dna: Electrostatic And Hydrophobic Interactions, Xiong Gong
Xiong Gong
Water-soluble, cationic conjugated polymer binds single-stranded DNA with higher affinity than it binds double-stranded or otherwise “folded” DNA. This stronger binding results from the greater hydrophobicity of single-stranded DNA. Upon reducing the strength of the hydrophobic interactions, the electrostatic attraction becomes the important interaction that regulates the binding between the water-soluble conjugated polymer and DNA. The different affinities between the cationic conjugated polymer and various forms of DNA (molecular beacons and its open state; single-stranded DNA and double-stranded DNA and single-stranded DNA and complex DNA folds) can be used to design a variety of biosensors.
Electrophosphorescence From A Conjugated Copolymer Doped With An Iridium Complex: High Brightness And Improved Operational Stability,
2014
The University of Akron
Electrophosphorescence From A Conjugated Copolymer Doped With An Iridium Complex: High Brightness And Improved Operational Stability, Xiong Gong
Xiong Gong
High efficiency electrophosphorescent light-emitting diodes (LEDs), with an emission peak at 600 nm, a luminance of 2200 cd m–2, and good operational stability were fabricated from a conjugated copolymer doped with an iridium complex. The devices exhibited an external quantum efficiency of 1.5 % and a luminous efficiency of 3 cd A–1. These results demonstrate that electrophosphorescent devices with high brightness and operational stability can be produced in the form of polymer LEDs fabricated by processing the active materials from solution.
Modern Science And Technological English-Chinese Dictionary,
2014
The University of Akron
Modern Science And Technological English-Chinese Dictionary, Xiong Gong
Xiong Gong
No abstract provided.
Temperature Dependence Of Electronic Energy Transfer From A Polymer Host To A Triplet Emitter In Light Emitting Diode Materials,
2014
The University of Akron
Temperature Dependence Of Electronic Energy Transfer From A Polymer Host To A Triplet Emitter In Light Emitting Diode Materials, Xiong Gong
Xiong Gong
We investigate the temperature dependence of electronic energy transfer between a polymer host, poly(N-vinylcarbazole) blended with 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole, and the triplet emitter tris[9,9-dihexyl-2-(phenyl-4′-(pyridin-2′′-yl))fluorene] iridium(III) (Ir(DPPF)3). The photophysics of the blend are similar to those of neat poly(N-vinylcarbazole), with two emitting species corresponding to shallow and deep excimer traps. When the blend is doped with Ir(DPPF)3, the deep trap emission is preferentially quenched. This quenching cannot be explained by simple Förster energy transfer to the dopant. Instead, the data are consistent with a rapid, temperature-dependent partitioning of the energy between the two host species and the Ir(DPPF)3, each of which decays independently.
Label-Free, Dual-Analyte Electrochemical Biosensors: A New Class Of Molecular-Electronic Logic Gates,
2014
The University of Akron
Label-Free, Dual-Analyte Electrochemical Biosensors: A New Class Of Molecular-Electronic Logic Gates, Xiong Gong
Xiong Gong
An “XOR” gate built using label-free, dual-analyte electrochemical sensors and the activation of this logic gate via changing concentrations of cocaine and the relevant cDNA as inputs are described.
High-Performance Polymer Light-Emitting Diodes Fabricated With A Polymer Hole Injection Layer,
2014
The University of Akron
High-Performance Polymer Light-Emitting Diodes Fabricated With A Polymer Hole Injection Layer, Xiong Gong
Xiong Gong
Enhanced luminance (L) and luminous efficiency (LE) of polymer light-emitting diodes(PLEDs) is demonstrated using poly(bis(tetraphenyldiamino)biphenyl-perfluorocyclobutane), poly(BTPD-Si-PFCB), as the hole injection layer. The monomer is cast directly onto the indium-tin-oxide anode and thermally polymerized in situ. Hole injection from poly(BTPD-Si-PFCB) into the “super yellow” derivative of poly(phenylene vinylene) and into several blue-emitting polymers is comparable to or better than that from poly(ethylenedioxythiophene):poly(styrene sulfonic acid) (PEDOT:PSSA). With poly(BTPD-Si-PFCB) as the hole injecting layer into “super yellow,” the performance is identical to that obtained with PEDOT:PSSA (LE≈8 cd/A with little fall-off, even at L>104 cd/m2)
High Performance Polymer Electrophosphorescent Leds,
2014
The University of Akron
High Performance Polymer Electrophosphorescent Leds, Xiong Gong
Xiong Gong
No abstract provided.
