A5029633721- Organic Electronics and Photovoltaics
- Conducting polymers and applications
- Perovskite Materials and Applications
- Crystallization and Solubility Studies
- Molecular Junctions and Nanostructures
- X-ray Diffraction in Crystallography
- Organic Light-Emitting Diodes Research
- Thin-Film Transistor Technologies
- Quantum Dots Synthesis And Properties
- Fullerene Chemistry and Applications
- Chalcogenide Semiconductor Thin Films
- Advanced Sensor and Energy Harvesting Materials
- Semiconductor materials and interfaces
- Luminescence and Fluorescent Materials
- DNA Repair Mechanisms
- Liquid Crystal Research Advancements
- Analytical Chemistry and Sensors
- Porphyrin and Phthalocyanine Chemistry
- Plant Genetic and Mutation Studies
- Mass Spectrometry Techniques and Applications
- Radiation Therapy and Dosimetry
- Photonic and Optical Devices
- Force Microscopy Techniques and Applications
- Semiconductor materials and devices
- Radiation Effects and Dosimetry
RIKEN Center for Emergent Matter Science
2016-2025
Tokyo University of Science
2021
RIKEN
1984-2021
Tokyo Institute of Technology
2011-2013
Ibaraki University
2013
Japan Science and Technology Agency
2011
Nagasaki University
1989-1992
Nippon Soken (Japan)
1991
Yokohama City University
1990-1991
Nagaoka University
1984
This work provides an efficient way to facilitate both electron and hole extraction in the designated interfaces of perovskite solar cells. A record power conversion efficiency 23.6% for mixed Sn–Pb cell devices is realized.
Abstract Ultraflexible organic photovoltaics have emerged as a potential power source for wearable electronics owing to their stretchability and lightweight nature. However, waterproofing ultraflexible without compromising mechanical flexibility conformability remains challenging. Here, we demonstrate waterproof through the in-situ growth of hole-transporting layer strengthen interface adhesion between active anode. Specifically, silver electrode is deposited directly on top layers, followed...
Eliminating the excess energetic driving force in organic solar cells leads to a smaller energy loss and higher device performance; hence, it is vital understand relation between interfacial energetics photoelectric conversion efficiency. In this study, we systematically investigate 16 combinations of four donor polymers acceptors planar heterojunction. The charge generation efficiency its electric field dependence correlate with difference singlet excited state transfer state. threshold 0.2...
Interfaces in thin-film photovoltaics play a pivotal role determining device efficiency and longevity. In this work, the top surface treatment of mixed tin-lead (≈1.26 eV) halide perovskite films for p-i-n solar cells is studied. Charge extraction promoted by treating with piperazine. This compound reacts organic cations at surface, modifying structure tuning interfacial energy level alignment. addition, combined C60 pyrrolidine tris-acid (CPTA) reduces hysteresis leads to efficiencies up...
Strongly bound excitons crucially affect the operation of organic optoelectronic devices. Nevertheless, precise experimental data on exciton binding energy semiconductors are lacking. In this study, we determine as difference between optical and transport bandgaps with a precision 0.1 eV. particular, electron affinities higher than 0.05 eV determined by low-energy inverse photoelectron spectroscopy allow us to gap energies such high precision. Through systematic comparison wide range...
New π-conjugated copolymers based on naphtho[2,3-b:6,7-b′]dithiophene-4,5,9,10-diimide (NDTI) combined with thiophene, thienothiophene, or dithienothiophene units are synthesized and used in field-effect transistors (FETs) organic solar cells (OSCs). The low-lying lowest unoccupied molecular orbital (LUMO) high-lying highest occupied (HOMO) levels of the polymers contribute to reducing injection barriers for both electrons holes, resulting ambipolar operation FET devices. charge mobilities...
The bulk photovoltaic effect (BPVE) has drawn intensive attention due to its unique features that cannot be accessed with the conventional effect. However, BPVE is observed in noncentrosymmetric materials and been studied mainly for inorganic materials. Here, we report a simple subphthalocyanine (SubPc) derivative assembles into columnar liquid crystal help of DC E-field. These assemblies exhibit over wide range wavelengths up 650 nm. Furthermore, just by sandwiching this assembly between...
Ultrathin (thickness less than 10 µm) organic photovoltaics (OPVs) can be applied to power soft robotics and wearable electronics. In addition high conversion efficiency, stability under various environmental stresses is crucial for the application of ultrathin OPVs. this study, authors realize highly air-stable (≈3 OPVs that possess efficiency (15.8%) an outstanding power-per-weight ratio 33.8 W g
Perovskite interfaces critically influence the final performance of photovoltaic devices. Optimizing them by reducing defect densities or improving contact with charge transporting material is key to further enhance efficiency and stability perovskite solar cells. Inverted (p–i–n) devices can particularly benefit here, as evident from various successful attempts. However, every reported strategy adapted specific cell structures compositions, affecting their robustness applicability other...
Energy levels of the first monolayer are manipulated at donor/acceptor interfaces in planar heterojunction organic photovoltaics by using molecular self-organization. A "cascade" energy landscape allows thermal-activation-free charge generation photoirradiation, destabilizes interfacial charge-transfer state, and suppresses bimolecular recombination, resulting a higher open-circuit voltage fill factor.
The power conversion efficiency of tin-based halide perovskite solar cells is limited by large photovoltage losses arising from the significant energy-level offset between and conventional electron transport material, fullerene C60. derivative indene-C60 bisadduct (ICBA) a promising alternative to mitigate this drawback, owing its superior energy level matching with most perovskites. However, less finely controlled disorder ICBA films leads extension band tails that limits resultant devices...
Abstract The secret to the success of mixed bulk heterojunctions (BHJs) in yielding highly efficient organic solar cells (OSCs) could reside molecular structures at their donor/acceptor (D/A) interfaces. In this study, we aimed determine effects energy and charge cascade interfaces by using well-defined planar (PHJs) as a model system. results showed that (1) structure enhanced V OC because it shuts down recombination pathway through transfer (CT) state with low energy, (2) layer having...
Despite the critical importance of density states (DOS) to electrical properties molecular semiconductors, there are few reliable measurement methods for DOS, especially edge regions with low DOS that determine charge conduction. Here, we evaluate occupied high sensitivity (down 10–5 relative peak maxima) using a commercially available photoelectron yield spectroscopy (PYS) system operated in air. The conduction edges both semiconducting polymers and molecules expressed as single Gaussian no...
Three isomeric derivatives of 2,2',2″-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H-benzimidazole) (TPBi) bearing ethyl groups on the N-phenyl moieties were synthesized to elucidate effects intramolecular interactions spontaneous orientation polarization (SOP) in thin films. The films TPBi displayed enhanced SOP with a surface potential change up 1.8 times that for TPBi, and p-substituted derivative exhibited largest reported date (+141.0 mV/nm). Density functional theory calculations...
AbstractWe have measured expression of transformed phenotypes in human embryo (HE) cells repeatedly irradiated with a dose 7·5 cGy per week throughout the life span these vitro. Irradiation was repeated until had accumulated 195 at which time reached equivalent their 26th passage and samples several passages were assayed for cell survival by colony formation, mutation hypoxanthin guanine phosphoribosyl transferase (HGPRT) locus transformation focus formation. The lifespan (mean population...
Abstract Preparation of highly crystalline organic semiconductor films is vital to achieving high performance in electronic devices. Here we report that surface segregated monolayers (SSMs) on top phenyl-C 61 -butyric acid methyl ester (PCBM) thin induce crystal growth the bulk, resulting a dramatic change structure form new phase. Highly ordered with large domain sizes several hundreds nanometers are formed uniaxial orientation perpendicular substrate. The molecular rearrangements SSMs...
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTBis(naphthothiophene diimide)indacenodithiophenes as Acceptors for Organic PhotovoltaicsJohan Hamonnet†, Masahiro Nakano*†, Kyohei Nakano‡, Hiroyoshi Sugino†, Kazuo Takimiya*†§, and Keisuke Tajima‡View Author Information† Emergent Molecular Function Research Group, RIKEN Center Matter Science (CEMS), 2-1, Hirosawa, Wako, Saitama 351-0198, Japan‡ Functional Polymers Team, Japan§ Department of Chemistry, Graduate School Science, Tohoku...
Intrachain hole delocalization vertical to donor and acceptor interface weakens coulombic interaction of the charge pairs facilitate separation in organic solar cells.
The use of singlet photocrosslinkers based on diazirine or azide has been investigated for organic photovoltaics (OPVs) to stabilize the morphology mixed bulk heterojunction (BHJ) films. photocrosslinking reactions in BHJs have major detrimental effects performance OPVs. This is striking contrast previous reports field-effect transistors, where these crosslinkers can solidify films without affecting charge transport properties. Based OPV results with layer-by-layer-deposited and transferred...
In this study, we designed and synthesized two nonfullerene acceptors (NFAs) based on 1H- 2H-benzo[d]imidazole (BIz) isomers, named 1-OBIA 2-OBIA, for organic photovoltaics (OPVs). Whereas possesses an electron-donating amine-type nitrogen atom electron-withdrawing imine-type atom, 2-OBIA atoms in the benzimidazole moiety. Owing to its more electron-rich central core, showed higher HOMO LUMO energy levels than 2-OBIA. Photovoltaic cells when paired with a benchmark polymer donor, PM6,...
The electric field dependence in the charge generation process of organic solar cells planar heterojunction and bulk structures is related to energetics molecular orientation at donor/acceptor interfaces.