A5060363291- Quantum Dots Synthesis And Properties
- Chalcogenide Semiconductor Thin Films
- TiO2 Photocatalysis and Solar Cells
- Conducting polymers and applications
- Perovskite Materials and Applications
- Advanced Photocatalysis Techniques
- Organic Electronics and Photovoltaics
- Transition Metal Oxide Nanomaterials
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Porphyrin and Phthalocyanine Chemistry
- Nanowire Synthesis and Applications
- Analytical Chemistry and Sensors
- Polydiacetylene-based materials and applications
- solar cell performance optimization
- Advanced Semiconductor Detectors and Materials
- Gas Sensing Nanomaterials and Sensors
- Silicon and Solar Cell Technologies
- Electrochemical sensors and biosensors
- Luminescence and Fluorescent Materials
- Polyoxometalates: Synthesis and Applications
- Advanced Nanomaterials in Catalysis
- Copper-based nanomaterials and applications
- Photoreceptor and optogenetics research
- Nanocluster Synthesis and Applications
The University of Tokyo
2015-2024
Tokyo University of Information Sciences
2021
Center for High Pressure Science and Technology Advanced Research
2019
Eneos (Japan)
1996-2011
Tokyo Institute of Technology
1987-2006
Mitsubishi Group (Japan)
2001
Potassium-doped organometal halide perovskite solar cells (PSCs) of more than 20% power conversion efficiency (PCE) without I-V hysteresis were constructed. The crystal lattice the was expanded with increasing potassium ratio, where both absorption and photoluminescence spectra shifted to longer wavelength, suggesting that optical band gap decreased. In case 5% K+, conduction minimum (CBM) became similar CBM level TiO2-Li. this situation, electron transfer barrier at interface between...
The improvement of solar cell performance in the near-infrared (near-IR) region is an important challenge to increase power conversion efficiency under one-sun illumination. PbS quantum-dot (QD)-based heterojunction cells with high near-IR were constructed by combining ZnO nanowire arrays QDs, which give a first exciton absorption band centering at wavelengths longer than 1 μm. morphology was systematically investigated achieve light-harvesting as well efficient carrier collection. QD/ZnO...
For improvement of solar cell performance, it is important to make efficient use near-infrared light, which accounts for ∼40% sunlight energy. Here we introduce plasmonic Ag nanocubes (NCs) colloidal PbS quantum dot/ZnO nanowire (PbS QD/ZnO NW) bulk-heterojunction cells, are characterized by high photocurrents, further in the photocurrent and power conversion efficiency (PCE) visible regions. The NCs exhibit strong far field scattering intense optical near wavelength region where light...
Abstract The extension of the light absorption photovoltaics into near-infrared region is important to increase energy conversion efficiency. Although progress lead halide perovskite solar cells remarkable, and high efficiency >20% has been reached, their limit on long-wavelength side ∼800 nm. To further enhance perovskite-based photovoltaics, a hybridized system with useful approach. Here we report panchromatic sensitizer, coded DX3, that exhibits broad response near-infrared, up ∼1100...
Abstract A compact TiO2 interlayer between fluorine-doped tin oxide (FTO) and perovskite in planar heterojunction solar cells is essential for effective charge extraction minimized recombination. The electrical property of the interface layer with thus important achieving high power conversion efficiency cells. motivation present study was to improve cell performance by improving TiO2/perovskite interface. Interestingly, a remarkable enhancement achieved treatment TiCl4 UV(O3).
Abstract For efficient hybrid solar cells based on organometal halide perovskites, the real origin of I–V hysteresis became a big issue and has been discussed widely. In this study, simulated curves different equivalent circuit models were validated with experimental planar perovskite cell power conversion efficiency (PCE) 18.0% 8.8% reverse scan (from open to short circuit) forward circuit), respectively. We found that an model series double diodes, capacitors, shunt resistances, single...
The present work has been supported by New Energy and Industrial Technology Development Organization (NEDO, Japan) and Japan Society for the Promotion of Science (JSPS) for Overseas Researchers. authors acknowledge Ajay Kumar Jena his help.
Abstract Almost all surfaces sensitive to the ambient environment are covered by water, whereas impacts of water on surface-dominated colloidal quantum dot (CQD) semiconductor electronics have rarely been explored. Here, strongly hydrogen-bonded hydroxylated lead sulfide (PbS) CQD is identified. The could pilot thermally induced evolution surface chemical environment, which significantly influences nanostructures, carrier dynamics, and trap behaviors in solar cells. aggravation hydroxylation...
N-fused carbazole-zinc porphyrin-free-base porphyrin triad featuring an ethynyl-linkage was synthesized; efficient sensitization as long 900 nm demonstrated and overall light-to-electricity conversion efficiency of 5.21% achieved under AM 1.5 G one sun illumination.
AgBiS2 nanocrystals (NCs) are nontoxic, lead-free, and near-infrared absorbing materials. Eco-friendly solar cells were constructed using interdigitated layers of ZnO nanowires (NWs) NCs, with the aim elongating otherwise short carrier diffusion length NC assembly. NCs uniformly infiltrated into NW a low-cost easily scalable dip coating method. The resulting NW/AgBiS2 structures provided efficient pathways in nanowire (NWSCs), composed transparent electrode/ZnO layer/P3HT hole transport...
A new osmium (Os) complex of the [Os(tcterpy)-(4,4'-bis(p-butoxystyryl)-2,2'-bipyridine)Cl]PF6 (Os-stbpy) has been synthesized and characterized for dye-sensitized solar cells (DSSCs). The Os-stbpy dye shows enhanced spin-forbidden absorptions around 900 nm. DSSCs with show a wide-band spectral response up to 1100 nm high overall conversion efficiency 6.1% under standard illumination.
Nanostructured solar cells are a promising area of research for the production low cost devices that may eventually be capable complementing or even replacing present technologies in field power generation. The use quantum dots (QDs) has evolved from being simple absorbers dye-sensitized to sustaining double functions and carrier transporters full solid state devices. In this work, we both optical electrical measurements explore diffusion limitations transport made heterostructure combining...
A systematic investigation into the performance of PbS quantum dot (QD)/ZnO nanowire (NW) solar cells in near-infrared (NIR) and short-wave infrared (SWIR) regions was carried out. The were confirmed to convert a wide range energy (3.54–0.62 eV, corresponding 0.35–2.0 μm). We found that working SWIR region had high open-circuit voltage (Voc). relatively Voc 0.25 V achieved even whose photocurrent onsets at approximately 0.64 eV (1.9 μm); this is as Ge cells, which have been used for III–V...
Abstract Here efficient organic photovoltaic devices fabricated from water‐based colloidal dispersions with donor:acceptor composite nanoparticles achieving up to 9.98% power conversion efficiency (PCE) are reported. This high for water processed solar cells is attributed morphology control by surface energy matching between the donor and acceptor materials. Indeed, due a low interfacial acceptor, no large phase separation occurs during nanoparticle formation process as well upon thermal...
Energy harvesting at low light intensities has recently attracted a great deal of attention perovskite solar cells (PSCs) which are regarded as promising candidate for indoor application. Anomalous hysteresis the PSCs complex issue reliable evaluation cell performance. In order to address these challenges, we constructed two new methods determinate power conversion efficiencies (PCEs) PSCs. The first setup is simulator based on emitting diodes (LEDs) allowing wider range intensities, ranging...
We have constructed heterojunction iodide ligand PbS quantum dot (QD) and ZnO nanowire (NW) solar cells. In these interdigitated structures, QDs are well-embedded within NWs grown on a dense layer. A Au back contact is directly formed the QD surface widely studied colloidal QD-based cells, active layer sandwiched between hole-blocking (or electron-accepting layer) electron-blocking (EBL) hole-transport layer). contrast, our cells contain no EBL except an additional thin capping layer, which...
Optical gaps and electrochromic efficiencies of sputtered tungsten oxide films are studied by focusing attention on the cluster size film. The consists O‐W‐O network with terminal W=O bonds its boundary. quantity increased surface area clusters. Raman scattering bands observed between 500 1100 cm−1. These characteristic film well reproduced combination four Gaussian shaped modes. ratio integrated intensities (W=O/O‐W‐O) these modes employed as measure size. is found to increase in elevation...
Abstract Perovskite solar cells (PSCs) are among the promising candidates to reach highest efficiency single‐junction due their band gap around 1.55 eV, strong absorption, and long charge carrier diffusion length. However, anomalous hysteresis observed in its current–voltage ( I–V ) curves that creates confusion about true has been a serious drawback for further improvement of stable power output. Hence, understanding origin is important discussed widely recent publications. Herein, PSCs...