A5101759117- Quantum Dots Synthesis And Properties
- Advanced Sensor and Energy Harvesting Materials
- Perovskite Materials and Applications
- 2D Materials and Applications
- Gas Sensing Nanomaterials and Sensors
- ZnO doping and properties
- Conducting polymers and applications
- Chalcogenide Semiconductor Thin Films
- Analytical Chemistry and Sensors
- Nanomaterials and Printing Technologies
- Nanocluster Synthesis and Applications
- Indoor and Outdoor Localization Technologies
- Robotics and Sensor-Based Localization
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Advanced Chemical Sensor Technologies
- Catalytic Processes in Materials Science
- Luminescence and Fluorescent Materials
- Gold and Silver Nanoparticles Synthesis and Applications
- Catalysis and Oxidation Reactions
- Advancements in Solid Oxide Fuel Cells
- Target Tracking and Data Fusion in Sensor Networks
- GaN-based semiconductor devices and materials
- Organic and Molecular Conductors Research
- Water-Energy-Food Nexus Studies
Massachusetts Institute of Technology
2021-2024
Korea University
2016-2021
Government of the Republic of Korea
2018-2019
Seoul Institute
2018-2019
Inha University
2017-2018
Sungkyunkwan University
2017
Korea Fisheries Resources Agency
2009
Changwon National University
2007
Abstract Highly sensitive temperature sensors are designed by exploiting the interparticle distance–dependent transport mechanism in nanocrystal (NC) thin films based on a thermal expansion strategy. The effect of ligands electronic, thermal, mechanical, and charge properties silver (Ag) NC expandable substrates poly(dimethylsiloxane) (PDMS) is investigated. While inorganic ligand‐treated Ag exhibit low coefficient resistance (TCR), organic extremely high TCR up to 0.5 K −1 , which highest...
All-nanocrystal (NC)-based and all-solution-processed wearable resistance temperature detectors (RTDs) are introduced. The charge transport mechanisms of Ag NC thin films engineered through various ligand treatments to design high performance RTDs. Highly conductive exhibiting metallic behavior with positive coefficients (TCRs) achieved tetrabutylammonium bromide treatment. showing hopping negative TCRs created organic All-solution-based, one-step photolithography techniques that integrate...
Metal organochalcogenides (MOCs) are an emerging class of luminescent hybrid organic–inorganic semiconductors, whose structures and properties can be tuned by organic functionalization substitutions their metal chalcogen elements. Herein, we present a new design strategy heterocyclic modification, resulting in the transformation prototypical two-dimensional (2D) silver phenylselenide (AgSePh) to zero-dimensional (0D) pyridinylselenide (AgSePy) via formation Ag–N bonds. At room temperature,...
Abstract Wearable strain sensors are widely researched as core components in electronic skin. However, their limited capability of detecting only a single axial strain, and low sensitivity, stability, opacity, high production costs hinder use advanced applications. Herein, multiaxially highly sensitive, optically transparent, chemically stable, solution‐processed demonstrated. Transparent indium tin oxide zinc nanocrystals serve metallic insulating metal–insulator matrix active materials for...
The use of two-dimensional (2D) materials in next-generation technologies is often limited by small lateral size and/or crystal defects. Here, we introduce a simple chemical strategy to improve the and overall quality 2D metal–organic chalcogenolates (MOCs), new class hybrid organic–inorganic semiconductors that can exhibit in-plane anisotropy blue luminescence. By inducing formation silver–amine complexes during solution growth method, increase average silver phenylselenolate (AgSePh)...
Silver phenylselenolate (AgSePh) is a hybrid organic-inorganic two-dimensional (2D) semiconductor exhibiting narrow blue emission, in-plane anisotropy, and large exciton binding energy. Here, we show that the addition of carefully chosen solvent vapors during chemical transformation metallic silver to AgSePh allows for control over size orientation crystals. By testing 28 (with different polarities, boiling points, functional groups), controlled resulting crystal from <200 nm up few μm....
Organic-inorganic hybrid materials present new opportunities for creating low-dimensional structures with unique light-matter interaction. In this work, we report a chemically robust yellow emissive one-dimensional (1D) semiconductor, silver 2,6-difluorophenylselenolate─AgSePhF2(2,6), member of the broader class semiconductors, metal-organic chalcogenolates. While phenylselenolate (AgSePh) crystallizes as two-dimensional (2D) van der Waals introduction fluorine atoms at (2,6) position phenyl...
Abstract All‐solution processed, high‐performance wearable strain sensors are demonstrated using heterostructure nanocrystal (NC) solids. By incorporating insulating artificial atoms of CdSe quantum dot NCs into metallic Au NC thin film matrix, metal–insulator heterostructures designed. This hybrid structure results in a shift close to the percolation threshold, modifying charge transport mechanism and enhancing sensitivity accordance with site theory. The number electrical pathways is also...
With the increase in interest wearable tactile pressure sensors for e-skin, researches to make nanostructures achieve high sensitivity have been actively conducted. However, limitations such as complex fabrication processes using expensive equipment still exist. Herein, simple lithography-free techniques develop pyramid-like metal/insulator hybrid utilizing nanocrystals (NCs) are demonstrated. Ligand-exchanged and unexchanged silver NC thin films used metallic insulating components,...
Next-generation devices and systems require the development integration of advanced materials, realization which inevitably requires two separate processes: property engineering patterning. Here, we report a one-step, ink-lithography technique to pattern engineer properties thin films colloidal nanocrystals that exploits their chemically addressable surface. Colloidal are deposited by solution-based methods form local chemical treatment is applied using an ink-printing simultaneously modify...
Multifunctional temperature–strain sensors that can simultaneously detect temperature and strain are fabricated through all-solution processes using colloidal Ag nanocrystals (NCs). Material architecture design introduced to efficiently distinguish signals, allowing accurate measurement from one sensor device. For material design, a ligand-exchange reduction process is developed increase the sensitivity. As result, higher coefficients of resistance, lower resistivity, gauge factor values...
We report a simple, solution-based, and postsynthetic process for simultaneous ligand exchange, surface passivation, doping of CdSe nanocrystals (NCs) the design high-performance field-effect transistors (FETs). Strong electronic coupling, effective trap n-type NCs could be achieved by simply immersing as-synthesized NC thin films into InX3 (X = Cl, Br, I) solution. The optical, chemical, structural properties these were analyzed, revealing successful exchange In doping. It is demonstrated...
The popularity of colloidal quantum dot (CQD) solar cells has increased owing to their tunable bandgap, multiple exciton generation, and low-cost solution processes. ZnO nanoparticle (NP) layers are generally employed as electron transport in CQD efficiently extract the electrons. However, trap sites unfavorable band structure as-synthesized NPs have hindered potential performance. Herein, we introduce a facile method NP annealing state. Electrical, structural, optical analyses demonstrated...
Silver phenylselenolate (AgSePh, also known as "mithrene") and silver phenyltellurolate (AgTePh, "tethrene") are two-dimensional (2D) van der Waals semiconductors belonging to an emerging class of hybrid organic-inorganic materials called metal-organic chalcogenolates. Despite having the same crystal structure, AgSePh AgTePh exhibit a strikingly different excitonic behavior. Whereas exhibits narrow, fast luminescence with minimal Stokes shift, comparatively slow that is significantly...
Anisotropic strain engineering has emerged as a powerful strategy for enhancing the optoelectronic performance of semiconductor nanocrystals. Here, we show that CdSe/CdS dot-in-rod structures offer platform fine-tuning optical response CdSe quantum dots through anisotropic strain. By controlling spatial position core within growing CdS nanorod shell, varying degrees uniaxial can be introduced. Placing cores at end induces strong asymmetric compression along c-axis wurtzite core, dramatically...
Layered hybrid perovskites exhibit emergent physical properties and exceptional functional performances, but the coexistence of lattice order structural disorder severely hinders our understanding these materials. One unsolved problem regards how dynamics are affected by dimensional engineering inorganic frameworks their interaction with molecular moieties. Here, we address this question using a combination spontaneous Raman scattering, terahertz spectroscopy, simulations. This approach...
We investigated the chemical effects of halide ligands on electromechanical properties Ag nanocrystal (NC) thin films for potential uses in wearable devices and sensors. The treatments induced changes sizes sintered NCs, interparticle distances, microscale surface morphologies. Various characterization techniques models were used to study origin nanoscale structures, their chemistries, electronic NC films. results indicated that led gauge factor, which varied from 5 600. On basis these...
The interaction between excitons and photons underlies a range of emergent technologies, such as directional light emission, molecular lasers, photonic circuits, polaritonic devices. Two the key parameters that impact exciton–photon coupling are binding energy relative orientations exciton dipole photon field. Tightly bound typically found in crystals, where nevertheless angular relationship with fields is difficult to control. Here, we demonstrate dipoles fields, anchored by metal–ligand...
Alloying is a powerful strategy for tuning the electronic band structure and optical properties of semiconductors. Here, we investigate thermodynamic stability excitonic mixed-chalcogen alloys two-dimensional (2D) hybrid organic-inorganic silver phenylchalcogenides (AgEPh; E = S, Se, Te). Using variety structural characterization techniques, demonstrate that AgSePh-AgTePh system forms homogeneous (AgSe
An ideal open meshed structure for a highly sensitive and transparent pressure sensor is simply fabricated by one-step chemical treatment.
Ligand exchange processes have been attracting tremendous interest and are necessary when fabricating nanocrystal (NC) thin films for various applications. As ligand based on solution treatment processes, understanding solvents' effects the process is necessary. Herein, we investigated of exchanging solvents rinsing silver (Ag) NC during steps. We studied relationships between solvent properties, such as polarity steric hindrance, structural, electronic, electromechanical properties films. A...