A5036842921- Organic Electronics and Photovoltaics
- Conducting polymers and applications
- Fullerene Chemistry and Applications
- Perovskite Materials and Applications
- Molecular Junctions and Nanostructures
- Organic Light-Emitting Diodes Research
- Analytical Chemistry and Sensors
- Quantum Dots Synthesis And Properties
- Advanced Sensor and Energy Harvesting Materials
- CO2 Reduction Techniques and Catalysts
- Photochemistry and Electron Transfer Studies
- Luminescence and Fluorescent Materials
- Electrochemical Analysis and Applications
- Chalcogenide Semiconductor Thin Films
- Semiconductor materials and interfaces
- Electrochemical sensors and biosensors
- Advanced Memory and Neural Computing
- Porphyrin and Phthalocyanine Chemistry
- Thin-Film Transistor Technologies
- Nanowire Synthesis and Applications
- Graphene research and applications
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Carbon Nanotubes in Composites
- Semiconductor materials and devices
Johannes Kepler University of Linz
2016-2025
Institute of Physical Chemistry
2007-2025
Private University College of Education of the Diocese of Linz
2015-2020
University of Groningen
2000-2018
New York University Press
2018
Materials Research Center
2002-2018
Cambridge University Press
2018
Division of Materials Research
2018
University of California, Santa Barbara
1992-2013
University of Bucharest
2012
Evidence for photoinduced electron transfer from the excited state of a conducting polymer onto buckminsterfullerene, C(60), is reported. After photo-excitation conjugated with light energy greater than pi-pi* gap, an to C(60) molecule initiated. Photoinduced optical absorption studies demonstrate different excitation spectrum composite as compared separate components, consistent photo-excited charge transfer. A spin resonance signal exhibits signatures both cation and anion. Because...
Recent developments in conjugated-polymer-based photovoltaic elements are reviewed. The photophysics of such photoactive devices is based on the photo-induced charge transfer from donor-type semiconducting conjugated polymers to acceptor-type or acceptor molecules as Buckminsterfullerene, C60. This reversible, ultrafast (within 100 fs) with a quantum efficiency approaching unity, and charge-separated state metastable (up milliseconds at 80 K). Being similar first steps natural...
We show that the power conversion efficiency of organic photovoltaic devices based on a conjugated polymer/methanofullerene blend is dramatically affected by molecular morphology. By structuring to be more intimate mixture contains less phase segregation methanofullerenes, and simultaneously increasing degree interactions between polymer chains, we have fabricated device with 2.5% under AM1.5 illumination. This nearly threefold enhancement over previously reported values for such device, it...
Abstract Efficiencies of organic solar cells based on an interpenetrating network a conjugated polymer and fullerene as donor acceptor materials still need to be improved for commercial use. We have developed postproduction treatment that improves the performance poly(3‐hexylthiophene) (P3HT) [6,6]‐phenyl C 61 ‐butyric acid methyl ester (PCBM) by means tempering cycle at elevated temperatures in which external voltage is simultaneously applied, resulting significant increase short‐circuit...
A series of highly soluble fullerene derivatives with varying acceptor strengths (i.e., first reduction potentials) was synthesized and used as electron acceptors in plastic solar cells. These derivatives, methanofullerene [6,6]-phenyl C61-butyric acid methyl ester (PCBM), a new azafulleroid, ketolactam quasifullerene, show variation almost 200 mV their potential. The open circuit voltage the corresponding devices found to correlate directly strength fullerenes, whereas it rather insensitive...
Application-specific requirements for future lighting, displays and photovoltaics will include large-area, low-weight mechanical resilience dual-purpose uses such as electronic skin, textiles surface conforming foils. Here we demonstrate polymer-based photovoltaic devices on plastic foil substrates less than 2 μm thick, with equal power conversion efficiency to their glass-based counterparts. They can reversibly withstand extreme deformation have unprecedented solar cell-specific weight....
Within the different organic photovoltaic devices conjugated polymer/fullerene bulk heterojunction approach is one of foci today's research interest. These are highly dependent on solid state nanoscale morphology two components (donor/acceptor) in photoactive layer. The need for finely phase separated polymer–fullerene blends expressed by limited exciton diffusion length present semiconductors. Typical distances that these photo-excitations can travel within a pristine material around 10–20...
We fabricated flexible transparent conducting electrodes by printing films of single-walled carbon nanotube (SWNT) networks on plastic and have demonstrated their use as for efficient, polymer-fullerene bulk-heterojunction solar cells. The method produces relatively smooth, homogeneous with a transmittance 85% at 550nm sheet resistance (Rs) 200Ω∕◻. Cells were the SWNT/plastic anodes identically to process optimized ITO/glass. Efficiencies, 2.5% (AM1.5G), are close ITO/glass affected...
The characterization of rectifying heterojunctions (diodes) fabricated from a semiconducting polymer, soluble derivative poly(phenylene-vinylene), and buckminsterfullerene, C60, are reported. Rectification ratios in the current versus voltage characteristics exceed 104. When illuminated, devices exhibit large photoresponse as result photoinduced electron transfer across heterojunction interface polymer (donor) onto C60 (acceptor). photodiode photovoltaic responses characterized. Photoinduced...
The insertion of thin interlayers LiF under the negative metal electrode (Al and Au) bulk heterojunction solar cells significantly enhances fill factor stabilizes high open circuit voltages. Compared to devices without interfacial layer, white light efficiencies increase by over 20% up ηeff∼3.3%. Substitution another insulating interlayer SiOx results in lower overall efficiencies. In case a LiF/Au electrode, substantial efficiency enhancement is observed compared pristine Au ηeff∼2.3% are reported.
Abstract The relation between the nanoscale morphology and associated device properties in conjugated polymer/fullerene bulk‐heterojunction “plastic solar cells” is investigated. We perform complementary measurements on solid‐state blends of poly[2‐methoxy‐5‐(3,7‐dimethyloctyloxy)]‐1,4‐phenylenevinylene (MDMO‐PPV) soluble fullerene C 60 derivative 1‐(3‐methoxycarbonyl) propyl‐1‐phenyl [6,6]C 61 (PCBM), spin‐cast from either toluene or chlorobenzene solutions. characterization nanomorphology...
Encouraging progress has been made over the last few years in field of photovoltaic solar cells using organic materials. Among different concepts which have proposed, bulk heterojunction approach (formed by blending donor type conjugated polymers and acceptors like fullerenes) is attractive significant improving power conversion efficiency these devices was obtained recently. One possible improvements this implementation new materials absorbing red near infrared part spectrum, where maximal...
A novel low-bandgap conjugated polymer (PTPTB, Eg = ∼ 1.6 eV), consisting of alternating electron-rich N-dodecyl-2,5-bis(2′-thienyl)pyrrole (TPT) and electron-deficient 2,1,3-benzothiadiazole (B) units, is introduced for thin-film optoelectronic devices working in the near infrared (NIR). Bulk heterojunction photovoltaic cells from solid-state composite films PTPTB with soluble fullerene derivative [6,6]-phenyl C61 butyric acid methyl ester (PCBM) as an active layer shows promising power...
We live in a world where the lifetime of electronics is becoming shorter, now approaching an average several months. This poses growing ecological problem. brief review will present some initial steps taken to address issue electronic waste with biodegradable organic materials. Many materials have been shown be biodegradable, safe, and nontoxic, including compounds natural origin. Additionally, unique features such suggest they useful biofunctional electronics; demonstrating functions that...
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 good stability against degradation in air. Inverters with gains 105 the first 110 third quadrant are demonstrated. Fabricated entirely from biodegradable compounds, these devices show large potential such materials for green electronics. Detailed facts importance to specialist readers published as ”Supporting Information”. Such documents...
Abstract Biocompatible‐ingestible electronic circuits and capsules for medical diagnosis monitoring are currently based on traditional silicon technology. Organic electronics has huge potential developing biodegradable, biocompatible, bioresorbable, or even metabolizable products. An ideal pathway such devices involves fabrication with materials from nature, found in common commodity Transistors an operational voltage as low 4–5 V, a source drain current of up to 0.5 μA on‐off ratio 3–5...
Abstract The evolution of nanomorphology within thin solid‐state films poly(3‐alkylthiophene):[6,6]‐phenyl‐C 61 butyric acid methyl ester (P3AT:PCBM) blends during the film formation and subsequent thermal annealing is reported. In detail, influence P3AT's alkyl side chain length on polymer/fullerene phase separation discussed. Butyl, hexyl, octyl, decyl, dodecyl groups are investigated. All P3ATs used were regioregular. To elucidate nanomorphology, atomic force microscopy (AFM), X‐ray...