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Recent Advances in Non‐Ti MXenes: Synthesis, Properties, and Novel Applications (2024)
Journal Article
Khan, K., Tareen, A. K., Ahmad, W., Hussain, I., Chaudhry, M. U., Mahmood, A., …Xie, Z. (2024). Recent Advances in Non‐Ti MXenes: Synthesis, Properties, and Novel Applications. Advanced Science, 2303998. https://doi.org/10.1002/advs.202303998

One of the most fascinating 2D nanomaterials (NMs) ever found is various members of MXene family. Among them, the titanium‐based MXenes, with more than 70% of publication‐related investigations, are comparatively well studied, producing fundamental f... Read More about Recent Advances in Non‐Ti MXenes: Synthesis, Properties, and Novel Applications.

The role of fused thiophene and naphthalene diimide (NDI) in shaping the optical and electrical properties of donor-acceptor polymers (2024)
Journal Article
Dang Anh, K., dos Santos, P. L., Saeed, M., Chaudhry, M. U., Bechtold, I. H., Batycki, A., …Ledwon, P. (2024). The role of fused thiophene and naphthalene diimide (NDI) in shaping the optical and electrical properties of donor-acceptor polymers. Organic Electronics, 129, Article 107058. https://doi.org/10.1016/j.orgel.2024.107058

Three polymers with general structure (D-A)n were designed and synthetized to investigate the interaction of strong donors and strong acceptors in polymer chain. They are based on different fused thiophenes (1Th: 4,4′-bis(2-ethylhexyl)-cyclopenta [2,... Read More about The role of fused thiophene and naphthalene diimide (NDI) in shaping the optical and electrical properties of donor-acceptor polymers.

Chemically processed CdTe thin films for potential applications in solar cells - Effect of Cu doping. (2024)
Journal Article
Butt, A. F., Azhar, M., Yousaf, H., Batoo, K. M., Khan, D., Noman, M., …Riaz, S. (2024). Chemically processed CdTe thin films for potential applications in solar cells - Effect of Cu doping. Heliyon, 10(3), Article e24492. https://doi.org/10.1016/j.heliyon.2024.e24492

Thin films of cadmium telluride (CdTe) have attained the attention of researchers due to the potential application in solar cells. However, cost-effective fabrication of solar cells based on thin films along with remarkable efficiency and control ove... Read More about Chemically processed CdTe thin films for potential applications in solar cells - Effect of Cu doping..

Nanostructured Channel for Improving Emission Efficiency of Hybrid Light-Emitting Field-Effect Transistors (2023)
Journal Article
Galán-González, A., Pander, P., MacKenzie, R. C. I., Bowen, L., Zeze, D. A., Borthwick, R. J., …Chaudhry, M. U. (2023). Nanostructured Channel for Improving Emission Efficiency of Hybrid Light-Emitting Field-Effect Transistors. ACS Photonics, 10(12), 4315-4321. https://doi.org/10.1021/acsphotonics.3c01080

We report on the mechanism of enhancing the luminance and external quantum efficiency (EQE) by developing nanostructured channels in hybrid (organic/inorganic) light-emitting transistors (HLETs) that combine a solution-processed oxide and a polymer h... Read More about Nanostructured Channel for Improving Emission Efficiency of Hybrid Light-Emitting Field-Effect Transistors.

Large Area Emission in p-Type Polymer-Based Light-Emitting Field-Effect Transistors by Incorporating Charge Injection Interlayers (2021)
Journal Article

Organic light-emitting field-effect transistors (LEFETs) provide the possibility of simplifying the display pixilation design as they integrate the drive-transistor and the light emission in a single architecture. However, in p-type LEFETs, simultane... Read More about Large Area Emission in p-Type Polymer-Based Light-Emitting Field-Effect Transistors by Incorporating Charge Injection Interlayers.

Cobalt-Doped ZnO Nanorods Coated with Nanoscale Metal-Organic Framework Shells for Water-Splitting Photoanodes (2020)
Journal Article

Developing highly efficient and stable photoelectrochemical (PEC) water splitting electrodes via inexpensive, liquid phase processing is one of the key challenges for the conversion of solar energy into hydrogen for sustainable energy production. ZnO... Read More about Cobalt-Doped ZnO Nanorods Coated with Nanoscale Metal-Organic Framework Shells for Water-Splitting Photoanodes.

Light‐Emitting Transistors Based on Solution‐Processed Heterostructures of Self‐Organized Multiple‐Quantum‐Well Perovskite and Metal‐Oxide Semiconductors (2019)
Journal Article

Solution‐processed hybrid organic–inorganic perovskite semiconductors have demonstrated remarkable performance for both photovoltaic and light‐emitting‐diode applications in recent years, launching a new field of condensed matter physics. However, th... Read More about Light‐Emitting Transistors Based on Solution‐Processed Heterostructures of Self‐Organized Multiple‐Quantum‐Well Perovskite and Metal‐Oxide Semiconductors.

Mobility Evaluation of [1]Benzothieno[3,2‑b][1]benzothiophene Derivatives: Limitation and Impact on Charge Transport (2018)
Journal Article

Amongst contemporary semiconductors many of the best performing materials are based on [1]benzothieno[3,2-b][1]benzothiophene (BTBT). Alkylated derivatives of these small molecules not only provide high hole mobilities but can also be easily processe... Read More about Mobility Evaluation of [1]Benzothieno[3,2‑b][1]benzothiophene Derivatives: Limitation and Impact on Charge Transport.

Nano-Alignment in Semiconducting Polymer Films: A Path to Achieve High Current Density and Brightness in Organic Light Emitting Transistors (2018)
Journal Article

Organic light emitting field effect transistors (LEFETs) integrate light emission of a diode with logic functions of a transistor into a single device architecture. This integration has the potential to provide simplified displays at low costs and ac... Read More about Nano-Alignment in Semiconducting Polymer Films: A Path to Achieve High Current Density and Brightness in Organic Light Emitting Transistors.

UV-Deep Blue-Visible Light-Emitting Organic Field Effect Transistors with High Charge Carrier Mobilities (2017)
Journal Article
Ullah, M., Wawrzinek, R., Nagiri, R. C., Lo, S., & Namdas, E. B. (2017). UV-Deep Blue-Visible Light-Emitting Organic Field Effect Transistors with High Charge Carrier Mobilities. Advanced Optical Materials, 5(8), Article 1600973. https://doi.org/10.1002/adom.201600973

Two non-single-crystal high-mobility single-layer light-emitting field-effect transistors (LEFETs) exhibiting narrow UV and deep-blue emission are described. The organic semiconductors are based on a [1]benzothieno[3,2-b][1]benzothiophene (BTBT) scaf... Read More about UV-Deep Blue-Visible Light-Emitting Organic Field Effect Transistors with High Charge Carrier Mobilities.

Host-Free Blue Phosphorescent Dendrimer Organic Light-Emitting Field-Effect Transistors and Equivalent Light-Emitting Diodes: A Comparative Study (2017)
Journal Article
Ullah, M., Tandy, K., Clulow, A. J., Burn, P. L., Gentle, I. R., Meredith, P., …Namdas, E. B. (2017). Host-Free Blue Phosphorescent Dendrimer Organic Light-Emitting Field-Effect Transistors and Equivalent Light-Emitting Diodes: A Comparative Study. ACS Photonics, 4(4), 754-760. https://doi.org/10.1021/acsphotonics.6b01019

Light-emitting field-effect transistors (LEFETs) integrate functions of an organic light-emitting diode (OLED) and a field-effect transistor, and hence offer significant advantages in simplifying the device architecture for next-generation active mat... Read More about Host-Free Blue Phosphorescent Dendrimer Organic Light-Emitting Field-Effect Transistors and Equivalent Light-Emitting Diodes: A Comparative Study.

Orange-Red-Light-Emitting Field-Effect Transistors Based on Phosphorescent Pt(II) Complexes with Area Emission (2016)
Journal Article
Wawrzinek, R., Muhieddine, K., Ullah, M., Koszo, P. B., Shaw, P. E., Grosjean, A., …Lo, S. (2016). Orange-Red-Light-Emitting Field-Effect Transistors Based on Phosphorescent Pt(II) Complexes with Area Emission. Advanced Optical Materials, 4(11), 1867-1874. https://doi.org/10.1002/adom.201600460

Two new heteroleptic Pt(II) complexes bearing an n-hexyloxy substituted phenyllepidine-based ligand and either a picolinate (pic) or acetylacetonate (acac) coligand are synthesized for use in organic light-emitting field-effect transistors (LEFETs).... Read More about Orange-Red-Light-Emitting Field-Effect Transistors Based on Phosphorescent Pt(II) Complexes with Area Emission.

Semitransparent and Low-Voltage Operating Organic Light-Emitting Field-Effect Transistors Processed at Low Temperatures (2016)
Journal Article
Ullah, M., Wawrzinek, R., Maasoumi, F., Lo, S., & Namdas, E. B. (2016). Semitransparent and Low-Voltage Operating Organic Light-Emitting Field-Effect Transistors Processed at Low Temperatures. Advanced Optical Materials, 4(7), 1022-1026. https://doi.org/10.1002/adom.201600050

A see-through organic light emitting field-effect transistor (LEFET) is realized by using a highly transparent, high mobility material. Low voltage operated LEFETs with increased optical and electrical characteristics are shown.

Hybrid Light-Emitting Transistors Based on Low-Temperature Solution-Processed Metal Oxides and a Charge-Injecting Interlayer (2015)
Journal Article
Ullah, M., Lin, Y., Muhieddine, K., Lo, S., Anthopoulos, T. D., & Namdas, E. B. (2016). Hybrid Light-Emitting Transistors Based on Low-Temperature Solution-Processed Metal Oxides and a Charge-Injecting Interlayer. Advanced Optical Materials, 4(2), 231-237. https://doi.org/10.1002/adom.201500474

The performance of solution and low-temperature processed hybrid light-emitting field-effect transistors is enahnced by a new development strategy. The manipulation of the work function at the oxide/polymer interface is presented for achieving high a... Read More about Hybrid Light-Emitting Transistors Based on Low-Temperature Solution-Processed Metal Oxides and a Charge-Injecting Interlayer.

Singlet Fission and Triplet Exciton Dynamics in Rubrene/Fullerene Heterojunctions: Implications for Electroluminescence. (2015)
Journal Article
Ullah, M., Yambem, S. D., Moore, E. G., Namdas, E. B., & Pandey, A. K. (2015). Singlet Fission and Triplet Exciton Dynamics in Rubrene/Fullerene Heterojunctions: Implications for Electroluminescence. Advanced Electronic Materials, 1(12), Article 1500229. https://doi.org/10.1002/aelm.201500229

The role of triplet excitons in rubrene/C60 heterojunctions is investigated through detailed spectroscopic studies of triplet generation routes in the neat and heterojunction films of rubrene and C60. Time-correlated single-photon counting experiment... Read More about Singlet Fission and Triplet Exciton Dynamics in Rubrene/Fullerene Heterojunctions: Implications for Electroluminescence..

Hybrid Area-Emitting Transistors: Solution Processable and with High Aperture Ratios. (2015)
Journal Article
Muhieddine, K., Ullah, M., Maasoumi, F., Burn, P. L., & Namdas, E. B. (2015). Hybrid Area-Emitting Transistors: Solution Processable and with High Aperture Ratios. Advanced Materials, 27(42), 6677-6682. https://doi.org/10.1002/adma.201502554

Area emission is realized in all-solution-processed hybrid light-emitting transistors (HLETs). A new HLET design is presented with increased aperture ratio, and optical and electrical characteristics are shown.

Defining the light emitting area for displays in the unipolar regime of highly efficient light emitting transistors (2015)
Journal Article
Ullah, M., Armin, A., Tandy, K., Yambem, S. D., Burn, P. L., Meredith, P., & Namdas, E. B. (2015). Defining the light emitting area for displays in the unipolar regime of highly efficient light emitting transistors. Scientific Reports, 5, Article 8818. https://doi.org/10.1038/srep08818

Light-emitting field effect transistors (LEFETs) are an emerging class of multifunctional optoelectronic devices. It combines the light emitting function of an OLED with the switching function of a transistor in a single device architecture. The dual... Read More about Defining the light emitting area for displays in the unipolar regime of highly efficient light emitting transistors.

Efficient and bright polymer light emitting field effect transistors. (2014)
Journal Article
Ullah, M., Tandy, K., Yambem, S. D., Muhieddine, K., Ong, W. J., Shi, Z., …Namdas, E. B. (2015). Efficient and bright polymer light emitting field effect transistors. Organic Electronics, 17, 371-376. https://doi.org/10.1016/j.orgel.2014.12.014

Light emitting field effect transistors (LEFETs) are emerging as a multi-functional class of optoelectronic devices. LEFETs can simultaneously execute light emission and the standard logic functions of a transistor in a single architecture. However,... Read More about Efficient and bright polymer light emitting field effect transistors..

High-Performance, Solution-Processed Non-polymeric Organic Photodiodes (2014)
Journal Article
Kim, I. K., Pal, B. N., Ullah, M., Burn, P. L., Lo, S., Meredith, P., & Namdas, E. B. (2015). High-Performance, Solution-Processed Non-polymeric Organic Photodiodes. Advanced Optical Materials, 3(1), 50-56. https://doi.org/10.1002/adom.201400385

High-performance, solution-processed, non-polymeric broadband organic photo­diodes (OPDs) with a dark current density of 0.11 nA cm-2, responsivity of 0.4 A W-1, and detectivity of up to 9.2 × 1012 Jones are demonstrated.

High-Mobility, Heterostructure Light-Emitting Transistors and Complementary Inverters (2014)
Journal Article
Ullah, M., Tandy, K., Li, J., Shi, Z., Burn, P. L., Meredith, P., & Namdas, E. B. (2014). High-Mobility, Heterostructure Light-Emitting Transistors and Complementary Inverters. ACS Photonics, 1(10), 954-959. https://doi.org/10.1021/ph500300n

Light-emitting field effect transistors (LEFETs) are optoelectronic devices that can simultaneously execute light emission and the standard logic functions of a transistor in a single device architecture. In this article, we show that ambipolar LEFET... Read More about High-Mobility, Heterostructure Light-Emitting Transistors and Complementary Inverters.

All Solution-Processed, Hybrid Light Emitting Field-Effect Transistors (2014)
Journal Article
Muhieddine, K., Ullah, M., Pal, B. N., Burn, P., & Namdas, E. B. (2014). All Solution-Processed, Hybrid Light Emitting Field-Effect Transistors. Advanced Materials, 26(37), 6410-6415. https://doi.org/10.1002/adma.201400938

All solution-processed, high performance hybrid light emitting transistors (HLETs) are realized. Using a novel combination of device architecture and materials a bilayer device comprised of an inorganic and organic semiconducting layer is fabricated... Read More about All Solution-Processed, Hybrid Light Emitting Field-Effect Transistors.

ITO-free top emitting organic light emitting diodes with enhanced light out-coupling (2013)
Journal Article
Yambem, S. D., Ullah, M., Tandy, K., Burn, P. L., & Namdas, E. B. (2014). ITO-free top emitting organic light emitting diodes with enhanced light out-coupling. Laser and Photonics Reviews, 8(1), 165-171. https://doi.org/10.1002/lpor.201300148

Bottom emitting organic light emitting diodes (OLEDs) can suffer from lower external quantum efficiencies (EQE) due to inefficient out-coupling of the generated light. Herein, it is demonstrated that the current efficiency and EQE of red, yellow, and... Read More about ITO-free top emitting organic light emitting diodes with enhanced light out-coupling.

Simultaneous Enhancement of Brightness, Efficiency, and Switching in RGB Organic Light Emitting Transistors (2013)
Journal Article
Ullah, M., Tandy, K., Yambem, S. D., Aljada, M., Burn, P. L., Meredith, P., & Namdas, E. B. (2013). Simultaneous Enhancement of Brightness, Efficiency, and Switching in RGB Organic Light Emitting Transistors. Advanced Materials, 25(43), 6213-6218. https://doi.org/10.1002/adma.201302649

An innovative design strategy for light emitting field effect transistors (LEFETs) to harvest higher luminance and switching is presented. The strategy uses a non-planar electrode geometry in tri-layer LEFETs for simultaneous enhancement of the key p... Read More about Simultaneous Enhancement of Brightness, Efficiency, and Switching in RGB Organic Light Emitting Transistors.

Indigo - A Natural Pigment for High Performance Ambipolar Organic Field Effect Transistors and Circuits (2011)
Journal Article
Irimia-Vladu, M., Głowacki, E. D., Troshin, P. A., Schwabegger, G., Leonat, L., Susarova, D. K., …Sariciftci, N. S. (2012). Indigo - A Natural Pigment for High Performance Ambipolar Organic Field Effect Transistors and Circuits. Advanced Materials, 24(3), 375-380. https://doi.org/10.1002/adma.201102619

Millenniums-old natural dye indigo - a “new” ambipolar organic semiconductor. Indigo shows balanced electron and hole mobilities of 1 × 10−2 cm2 V−1 s−1 and good stability against degradation in air. Inverters with gains of 105 in the first and 110 i... Read More about Indigo - A Natural Pigment for High Performance Ambipolar Organic Field Effect Transistors and Circuits.

Effect of source-drain electric field on the Meyer–Neldel energy in organic field effect transistors (2011)
Journal Article
Ullah, M., Pivrikas, A., Fishchuk, I., Kadashchuk, A., Stadler, P., Simbrunner, C., …Sitter, H. (2011). Effect of source-drain electric field on the Meyer–Neldel energy in organic field effect transistors. Applied Physics Letters, 98(22), https://doi.org/10.1063/1.3584131

We studied the influence of the lateral source-drain electric field on the Meyer–Neldel phenomenon observed for the charge mobility measured in C60-based organic field effect transistors (OFETs). It was found that the characteristic Meyer-Neldel temp... Read More about Effect of source-drain electric field on the Meyer–Neldel energy in organic field effect transistors.

Electric field dependent activation energy of electron transport in fullerene diodes and field effect transistors: Gill’s law (2011)
Journal Article
Pivrikas, A., Ullah, M., Sitter, H., & Sariciftci, N. (2011). Electric field dependent activation energy of electron transport in fullerene diodes and field effect transistors: Gill’s law. Applied Physics Letters, 98(9), Article 092114. https://doi.org/10.1063/1.3557503

The electric field and temperature dependence of the electron mobility is studied comparatively in the bulk of fullerene (C60) diodes and at the interface with dielectric of organic field effect transistors (OFETs). Electron mobility values follow... Read More about Electric field dependent activation energy of electron transport in fullerene diodes and field effect transistors: Gill’s law.

Meyer–Neldel rule for charge carrier transport in fullerene devices: A comparative study (2010)
Journal Article
Pivrikas, A., Ullah, M., Singh, T., Simbrunner, C., Matt, G., Sitter, H., & Sariciftci, N. (2011). Meyer–Neldel rule for charge carrier transport in fullerene devices: A comparative study. Organic Electronics, 12(1), 161-168. https://doi.org/10.1016/j.orgel.2010.10.014

Charge transport is comparatively studied in the bulk and at the interface of disordered fullerene films fabricated using physical vapour deposition. Charge carrier concentration and temperature dependent electron mobilities are comparatively studied... Read More about Meyer–Neldel rule for charge carrier transport in fullerene devices: A comparative study.

Environmentally sustainable organic field effect transistors (2010)
Journal Article
Irimia-Vladu, M., Troshin, P. A., Reisinger, M., Schwabegger, G., Ullah, M., Schwoediauer, R., …Razumov, V. F. (2010). Environmentally sustainable organic field effect transistors. Organic Electronics, 11(12), 1974-1990. https://doi.org/10.1016/j.orgel.2010.09.007

Environmentally sustainable systems for the design, production, and handling of electronic devices should be developed to solve the dramatic increase in electronic waste. Sustainability in plastic electronics may be the production of electronic devic... Read More about Environmentally sustainable organic field effect transistors.

Temperature dependence of the charge carrier mobility in disordered organic semiconductors at large carrier concentrations (2010)
Journal Article
Fishchuk, I., Kadashchuk, A., Genoe, J., Ullah, M., Sitter, H., Singh, T. B., …Bässler, H. (2010). Temperature dependence of the charge carrier mobility in disordered organic semiconductors at large carrier concentrations. Physical review B, 81(4), Article 045202. https://doi.org/10.1103/physrevb.81.045202

Temperature-activated charge transport in disordered organic semiconductors at large carrier concentrations, especially relevant in organic field-effect transistors (OFETs), has been thoroughly considered using a recently developed analytical formali... Read More about Temperature dependence of the charge carrier mobility in disordered organic semiconductors at large carrier concentrations.

Electrical response of highly ordered organic thin film metal-insulator-semiconductor devices (2009)
Journal Article
Ullah, M., Taylor, D., Schwödiauer, R., Sitter, H., Bauer, S., Sariciftci, N., & Singh, T. B. (2009). Electrical response of highly ordered organic thin film metal-insulator-semiconductor devices. Journal of Applied Physics, 106(11), Article 114505. https://doi.org/10.1063/1.3267045

We report a detailed investigation of the electrical properties of organic field-effect transistors (OFETs) and metal-insulator-semiconductor (MIS) capacitors formed from highly ordered thin films of C60C60 as the active semiconductor and divinyltetr... Read More about Electrical response of highly ordered organic thin film metal-insulator-semiconductor devices.