A5049333485- Organic Electronics and Photovoltaics
- Conducting polymers and applications
- Perovskite Materials and Applications
- Block Copolymer Self-Assembly
- Organic Light-Emitting Diodes Research
- Advanced Polymer Synthesis and Characterization
- Quantum Dots Synthesis And Properties
- Liquid Crystal Research Advancements
- Advanced Sensor and Energy Harvesting Materials
- Advanced Memory and Neural Computing
- Polymer Surface Interaction Studies
- Thin-Film Transistor Technologies
- Advanced Materials and Mechanics
- Chalcogenide Semiconductor Thin Films
- Luminescence and Fluorescent Materials
- Advancements in Battery Materials
- Advanced Photocatalysis Techniques
- 2D Materials and Applications
- Supramolecular Self-Assembly in Materials
- Material Dynamics and Properties
- Photonic Crystals and Applications
- Semiconductor materials and devices
- Machine Learning in Materials Science
- Polymer crystallization and properties
- Advanced Battery Materials and Technologies
Pohang Accelerator Laboratory
2016-2025
Pohang University of Science and Technology
2016-2025
Pohang TechnoPark (South Korea)
2023-2024
Inha University
2023
Government of the Republic of Korea
2015-2021
Seoul National University
2020
Korea Post
2019
Yonsei University
2008-2014
University of Massachusetts Amherst
2008
Systematic side-chain engineering has been performed for diketopyrrolopyrrole-selenophene vinylene selenophene (DPP-SVS) polymers to determine the optimal geometries most efficient charge transport, and structure–property relationship thoroughly investigated using a range of analyses. A series DPP-SVS polymers, ranging from 25-DPP-SVS 32-DPP-SVS, with branched alkyl groups containing linear spacer C2 C9 synthesized, electrical performance these is significantly dependent on both length group...
Abstract In this study, we employ a combination of various in-situ surface analysis techniques to investigate the thermally induced degradation processes in MAPbI 3 perovskite solar cells (PeSCs) as function temperature under air-free conditions (no moisture and oxygen). Through comprehensive approach that combines grazing-incidence wide-angle X-ray diffraction (GIWAXD) high-resolution photoelectron spectroscopy (HR-XPS) measurements, confirm structure film changes an intermediate phase...
Abstract Establishing multi-colour patterning technology for colloidal quantum dots is critical realising high-resolution displays based on the material. Here, we report a solution-based processing method to form patterns of using light-driven ligand crosslinker, ethane-1,2-diyl bis(4-azido-2,3,5,6-tetrafluorobenzoate). The crosslinker with two azide end groups can interlock ligands neighbouring upon exposure UV, yielding chemically robust dot films. Exploiting crosslinking process,...
Abstract Insufficient charge extraction at the interfaces between light‐absorbing perovskites and transporting layers is one of drawbacks state‐of‐the‐art perovskite solar cells. Surface treatments and/or interface engineering are necessary to approach Shockley–Queisser limit. In this work, novel 2D layered perovskites, such as CHA 2 PbI 4 (CHAI = cyclohexylammonium iodide) CHMA (CHMAI cyclohexylmethylammonium iodide), introduced in 3D hole by a simple solution process 2D/3D heterojunction...
The optimization of the number fluorine substitution in D–A polymers composed difluorobithiophene and benzothiadiazole reveals that polymer with mono-fluorinated exhibits a PCE 9.14%.
The self-assembly of block copolymers (BCPs) is emerging as a promising route for numerous applications to generate templates and scaffolds the fabrication nanostructured materials. Here, we present an overview recent progress in directed BCPs with focus on guiding assemblies extreme (small large) features over large areas. We introduce inorganic-containing hybrid that enable access ultra-small feature sizes. To achieve desired orientation lateral ordering BCP microdomains, discuss routes...
Molecular orientation, with respect to donor/acceptor interface and electrodes, plays a critical role in determining the performance of all‐polymer solar cells (all‐PSCs), but is often difficult rationally control. Here, an effective approach for tuning molecular crystallinity orientation naphthalenediimide‐bithiophene‐based n‐type polymers (P(NDI2HD‐T2)) by controlling their number average weights ( M n ) reported. A series P(NDI2HD‐T2) different 13.6 P L ), 22.9 49.9 kg mol −1 H are...
For realizing flexible perovskite solar cells (PSCs), it is important to develop low‐temperature processable interlayer materials with excellent charge transporting properties. Herein, a novel polymeric hole‐transport material based on 1,4‐bis(4‐sulfonatobutoxy)benzene and thiophene moieties (PhNa‐1T) its application as layer (HTL) of high‐performance inverted‐type PSCs are introduced. Compared the conventionally used poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS),...
The directed assembly of block copolymer nanostructures with large periods exceeding 100 nm remains challenging because the translational ordering long-chained is hindered by its very low chain mobility. Using a solvent-vapor annealing process neutral solvent, which was sequentially combined thermal process, we demonstrate rapid evolution perpendicularly oriented lamellar morphology in high molecular weight films on substrate. synergy topographically patterned substrate facilitated...
Based on the integrated consideration and engineering of both conjugated backbones flexible side chains, solution‐processable polymeric semiconductors consisting a diketopyrrolopyrrole (DPP) backbone finely modulated branching chain ( ε ‐branched chain) are reported. The subtle change in point from alters π−π stacking lamellar distances between polymer backbones, which has significant influence charge‐transport properties turn performances field‐effect transistors (FETs). In addition to...
Nanoporous structures were obtained by the self-assembly of polystyrene-b-poly(methyl methacrylate) (PS-b-PMMA) block copolymers (BCP) where, in thick films, cylindrical microdomains oriented normal to substrate and air interfaces, interior randomly oriented. Continuous nanopores that penetrated through film readily produced a simple preferential swelling PMMA microdomains. The confined rapid contraction generated well-defined uniform pores with diameters 17.5 nm. size selectivity rejection...
We synthesized a donor polymer of bis(2-ethylhexyl)thiophene-substituted benzodithiophene (BDT-Th) and 1,3-bis(2-ethylhexyl)-5,7-di(thiophene-2-yl)benzo[1,2-c:4,5-c′]dithiophene-4,8-dione, for which the BDT-Th unit includes chlorine sulfur-bridged 2-ethylhexyl in thiophene side group. When compared with PBDB-TF, fluorine BDT-Th, PBDB-TSCl shows more efficient exciton dissociation charge generation, is probably because large dipole moment changes from ground to excited states lead reduced...
The layered sodium transition metal oxide, NaTMO2 (TM = metal), with a binary or ternary phases has displayed outstanding electrochemical performance as new class of strategy cathode materials for sodium-ion batteries (SIBs). Herein, an in-depth phase analysis developed Na1-x TMO2 materials, Na0.76 Ni0.20 Fe0.40 Mn0.40 O2 P2- and O3-type (NFMO-P2/O3) is offered. Structural visualization on atomic scale also provided the following findings are unveiled: i) existence mixed-phase intergrowth...
We explore the potential of employing diketopyrrolopyrrole (DPP) based π-conjugated OSs as a hole transport layer material in heteroatom-doped hematite (Ti–Fe2O3/Ge–Fe2O3) photoanodes for efficient photoelectrochemical water splitting. The siloxane-modified polymer (PSi) with high carrier mobility and crystallinity revealed great to extract holes by forming built-in while showing stability an alkaline electrolyte oxidation. Because easy extraction subsequent fast property PSi interlayer...
Abstract Crystallization kinetic controls the crystallographic orientation, inducing anisotropic properties of materials. As a result, preferential orientation with advanced optoelectronic can enhance photovoltaic devices' performance. Although incorporation additives is one most studied methods to stabilize photoactive α ‐phase formamidinium lead tri‐iodide ( ‐FAPbI 3 ), no studies focus on how affect crystallization kinetics. Along role methylammonium chloride (MACl) as “stabilizer” in...
Abstract Mechanochromic photonic materials present promising prospects for enhancing diverse facets of human life. Cholesteric liquid crystal elastomers (CLCEs) immediate mechanochromic properties, allowing their utility in various fields, including camouflages, textiles, and anticounterfeiting. Nonetheless, it is essential to provide differentiated color information corresponding types degrees deformation practical use real Herein, the responses CLCEs are investigated using optical rotation...
Organic photodiodes (OPDs) are a significant focus for the next-generation of light-detection technologies. However, organic semiconductors in OPDs still face key challenges, such as low carrier mobilities and limited efficiency generating photon-induced signals, which affect detectable resolution dynamic range. In this study, characterization interaction between polymeric bulk heterojunctions two-dimensional (2D) transition metal dichalcogenides (MoS2) reveals an enhancement photocurrent...
Abstract A general methodology is reported to create organic–inorganic hybrid metal halide perovskite films with enlarged and preferred‐orientation grains. Simply pressing polyurethane stamps hexagonal nanodot arrays on partially dried intermediate can cause pressure‐induced crystallization. This crystallization allows prepare highly efficient solar cells (PSCs) because the grains low‐angle grain boundaries in exhibit suppressed nonradiative recombination. Consequently, photovoltaic response...
Abstract An iodine‐free solid‐state dye‐sensitized solar cell (ssDSSC) is reported here, with 6.8% energy conversion efficiency—one of the highest yet for N719 dye—as a result enhanced light harvesting from increased transmittance an organized mesoporous TiO 2 interfacial layer and good hole conductivity solid‐state‐polymerized material. The (OM‐TiO ) prepared on large‐area substrates by sol‐gel process, confirmed scanning electron microscopy (SEM) grazing incidence small‐angle X‐ray...