A5086990821- Organic Electronics and Photovoltaics
- Conducting polymers and applications
- TiO2 Photocatalysis and Solar Cells
- Perovskite Materials and Applications
- Advanced Photocatalysis Techniques
- Thin-Film Transistor Technologies
- Organic Light-Emitting Diodes Research
- Quantum Dots Synthesis And Properties
- Nanowire Synthesis and Applications
- Molecular Junctions and Nanostructures
- Transition Metal Oxide Nanomaterials
- Chalcogenide Semiconductor Thin Films
- Advanced Nanomaterials in Catalysis
- solar cell performance optimization
- Advanced Sensor and Energy Harvesting Materials
- Photochemistry and Electron Transfer Studies
- Solid-state spectroscopy and crystallography
- Photonic Crystals and Applications
- Semiconductor materials and interfaces
- Luminescence and Fluorescent Materials
- ZnO doping and properties
- Electrochemical sensors and biosensors
- Copper-based nanomaterials and applications
- Silicon and Solar Cell Technologies
- Fullerene Chemistry and Applications
Ewha Womans University
2016-2025
Ewha Womans University Medical Center
2012-2021
Asan Medical Center
2020
Ulsan College
2020
University of Ulsan
2020
Center for NanoScience
2001-2017
Seoul Institute
2016
Government of the Republic of Korea
2014-2016
Korea Institute of Science and Technology
2007-2014
Korea Advanced Institute of Science and Technology
2011
The effects of annealing and fullerene loading in regioregular poly(3-hexylthiophene) (P3HT) 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C61 (PCBM) based bulk heterojunction photovoltaics have been investigated. Under specific conditions, a combination morphological electronic factors can be brought to play achieve optimal filling factors, open-circuit voltage (Voc), short-circuit current density (Jsc). We demonstrate that this occurs at surprisingly low loadings PCBM temperatures nearing the...
Nanoporous TiO2 structures were successfully applied for the fabrication of DSC electrodes, providing high surface areas and large pore sizes at same time. High photocurrent was induced in these DSCs by great adsorption dye molecules efficient electrolyte diffusion, caused generated hierarchical layer.
We have synthesized a highly efficient organic dye for dye-sensitized solar cell; the overall solar-to-energy conversion efficiency was 9.1% at AM 1.5 illumination (100 mW cm−2): short-circuit current density (Jsc) = 18.1 mA cm−2, open circuit photovoltage (Voc) 743 mV and fill factor (ff) 0.675.
The authors have fabricated thin film polymer photovoltaics using 1-(3-methoxycarbonyl)propyl-1-phenyl-(6,6)C61 within regioregular poly(3-hexylthiophene) bulk heterojunction absorbing layers. Using thermal annealing at temperatures approaching the glass transition temperature, they examined formation of nanodomains matrix. These domains modify charge transport pathways in such a way as to allow for efficient use thicker This results nearly 20% gain overall performance this system with...
Formation of a controlled fullerene mesophase within an organic host system has enabled us to create high-power conversion efficiency photovoltaics. This is formed using thermal gradients that provide fluidic mobility the fullerenes allowing for greater dispersion nanocrystalline 1-(3-methoxycarbonyl)propyl-1-phenyl-(6,6)C61 (PCBM) regioregular poly(3-hexylthiophene) (P3HT). From this reorganization component materials in matrix overall jumps dramatically from roughly 2.4% 5.2%.
The performance of dye-sensitized solar cells (DSSCs) consisting anatase TiO2 nanoparticles that were synthesized via a two-step sol−gel process was investigated using electron transport and optical characterizations. Spherical with the average diameter 20 nm, elongated nanorods an aspect ratio (AR) 5, nanowires AR = 10 synthesized. possess narrow size distribution, high crystallinity, negligible surface defects residual organics, which is very suitable for achieving highly efficient...
We investigated the performance of ambipolar field-effect transistors based on a series alternating low band gap polymers oligothiophene and diketopyrrolopyrrole (DPP). The contain units terthiophene [T3] thiophene-thienothiophene-thiophene [T2TT] DPP carrying branched alkyl chains 2-hexyldecyl [HD] or 2-octyldodecyl [OD]. structural variation allows us to do systematic study relationship between interchain stacking/ordering semiconducting their resulting device performance. On basis...
We obtained improved poly(3-octylthiophene) (P3OT)/C60 bulk heterojunction photovoltaic devices by doping with stable and highly electrically conductive Au Ag nanoparticles. Doped showed 50–70% efficiency, the nanoparticles exhibiting greatest increase in efficiency. suggest that a dominate mechanism for efficiency enhancement of doped device is electrical conductivity through introduction “dopant” levels within band gap P3OT.
Abstract Polymer solar cells (PSCs) are fabricated using a novel film deposition method, the electrostatic spray (e‐spray) technique. Stable atomization and uniform of polymer blend by e‐spray achieved manipulating solution concentration, solvent composition, electric field. The performance PSCs is primarily influenced inherent morphology e‐sprayed polymer‐blend active layers, which significantly different from that conventional films formed spin‐coating (SC) method. intrinsically...
We report highly efficient organic photosensitizers containing pi-conjugated alkoxy-substituted oligophenylenevinylene linkers with electron donor-acceptor units for dye-sensitized solar cells. TA-DM-CA showed an overall solar-to-energy conversion efficiency of 9.67% at AM 1.5 illumination (100 mW cm(-2)).
To achieve commercialization and widespread application of next-generation photovoltaics, it is important to develop flexible cost-effective devices. Given this, the elimination expensive transparent conducting oxides (TCO) replacement conventional glass substrates with plastic presents a viable strategy realize extremely low-cost photovoltaics potentially wide applicability. this end, we report completely TCO-free dye-sensitized solar cell (DSSC) fabricated on substrate using unique...
A series of thienyl-substituted methanofullerenes as electron acceptors for bulk-heterojuction solar cells with poly(3-hexylthiophene) (P3HT) were synthesized and characterized respect to electrochemical photophysical properties. The first one-electron reduction potentials the higher adducts are shifted toward more negative values by ∼100 mV compared monoadduct. As a result, composed bisadduct (2) trisadduct exhibit larger open-circuit voltage (Voc) than cell P3HT [6,6]-phenyl-C61-butyric...
In this study, we developed a novel nanostructured polymer nanofiber/TiO2 nanoparticle composite photoelectrode with high bendability by spray-assisted electrospinning method. The film is used as the in plastic dye-sensitized solar cells (DSCs). polymer/TiO2 has structure similar to that of fiber-reinforced composite; matrix contains TiO2 nanoparticles, and PVDF nanofibers are embedded matrix. Compared conventional DSCs, composite-based DSCs show outstanding bending stability because prevent...
Low‐temperature solution‐processed high‐efficiency colloidal quantum dot (CQD) photovoltaic devices are developed by improving the interfacial properties of p–n heterojunctions. A unique conjugated polyelectrolyte, WPF‐6‐oxy‐F, is used as an interface modification layer for ZnO/PbS‐CQD With insertion this interlayer, device performance dramatically improved. The origins improvement determined and it found that multifunctionality WPF‐6‐oxy‐F interlayer offers following essential benefits...
Abstract Low‐cost dye‐sensitized solar cells have attracted much attention because of their unique characteristics transparency and various colors. A cell is composed a dye‐coated nanocrystalline wide‐bandgap semiconductor, redox electrolyte platinum counter‐electrode. Transparency colors are attributed to 10–20 μm thick semiconductor film with particle size about nm difference in HOMO–LUMO energies the dye molecules, respectively. biomimetic working principle enables effective electron...
Long-range ordered cubic mesoporous TiO2 films with 300 nm thickness were fabricated on fluorine-doped tin oxide (FTO) substrate by evaporation-induced self-assembly (EISA) process using F127 as a structure-directing agent. The prepared film (Meso-TiO2) was applied an interfacial layer between the nanocrystalline (NC-TiO2) and FTO electrode in dye-sensitized solar cell (DSSC). introduction of Meso-TiO2 increased Jsc from 12.3 to 14.5 mA/cm2, Voc 55 mV, whereas there no appreciable change...
Abstract Colorful, semitransparent organic photovoltaic cells (OPVs) are increasing in demand due to their applicability aesthetically fashioned power‐generating windows. The traditional method of generating different colors OPVs has been through employing active materials exhibiting distinct absorption spectra. This can complicate fabrication processes for production and cause deviations device performance among differently colored OPVs. Herein, colorful with a single broadband‐absorbing...
A highly efficient sequentially deposited bilayer (SD-bilayer) of polymer/fullerene organic photovoltaic (OPV) device is developed via the solution process. Herein, we resolve two essential problems regarding construction an SD-bilayer OPV. First, process fabrication resolved by incorporating ordering agent (OA) to polymer solution, which improves chain and prevents bottom-layer from dissolving into top-layer solution. Second, a non-planar heterojunction with large surface area formed...
Abstract A molecular design is presented for tailoring the energy levels in D-π-A organic dyes through fluorination of their acceptor units, which aimed at achieving efficient dye-sensitized solar cells (DSSCs). This achieved by exploiting chemical structure common and incorporating one or two fluorine atoms ortho -positions cyanoacetic acid as additional units. As number incorporated increases, LUMO level dye gradually lowered due to electron-withdrawing effect fluorine, ultimately results...
Semitransparent colorful organic solar cells (OSC) provide exciting opportunities for harnessing sunlight as colored windows. Previously, color filter (CF) electrodes on were demonstrated via vacuum-deposition techniques, resulting in deposition-induced damage. Thus, we present CF integrated photovoltaics (CF-OPVs) using solution-processed TiO2-AcAc the dielectric component. The noninvasive processing substantially expands range of usable active materials, allowing device to display pure and...