A5033679062- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Molecular Junctions and Nanostructures
- Organic Light-Emitting Diodes Research
- Graphene research and applications
- Luminescence and Fluorescent Materials
- Photochemistry and Electron Transfer Studies
- Electrocatalysts for Energy Conversion
- Carbon Nanotubes in Composites
- Topological Materials and Phenomena
- Synthesis and Properties of Aromatic Compounds
- Advancements in Battery Materials
- Advanced Battery Materials and Technologies
- Organic Electronics and Photovoltaics
- Catalytic Processes in Materials Science
- Lanthanide and Transition Metal Complexes
- Quantum Dots Synthesis And Properties
- Catalysts for Methane Reforming
- Nanocluster Synthesis and Applications
- Advanced Chemical Physics Studies
- Chalcogenide Semiconductor Thin Films
- Sulfur-Based Synthesis Techniques
- Quantum-Dot Cellular Automata
- Machine Learning in Materials Science
- MXene and MAX Phase Materials
National Taiwan Normal University
2016-2025
Massachusetts Institute of Technology
2011-2013
National Taiwan University
2006
Institute of Chemistry, Academia Sinica
2006
The correlation between molecular packing structure and its room-temperature phosphorescence (RTP), hence rational promotion of the intensity, remains unclear. We herein present racemism enhanced RTP chiral chromophores by 2,2-bis-(diphenylphosphino)-1,1-napthalene (rac-BINAP) in comparison to counterparts. result shows that rac-BINAP crystal with denser density, consistent a long standing Wallach's rule, exhibits deeper red at 680 nm than cross alternative R- S- forms significantly retards...
Ideal catalysts for the oxygen reduction reaction (ORR) have been searched and researched decades with goal to overcome overpotential problem in proton exchange membrane fuel cells. A recent experimental study reports application of Pt nanoparticles on newly discovered 2D material, MXene, high stability good performance ORR. In this work, we simulate Ti n+1C nT x Pt-decorated Pt/v-Ti ( n = 1-3, T O and/or F) surfaces by first-principles calculations. We focus termination effects which may be...
We report O-H----S hydrogen-bond (H-bond) formation and its excited-state intramolecular H-bond on/off reaction unveiled by room-temperature phosphorescence (RTP). In this seminal work, phenomenon is demonstrated with 7-hydroxy-2,2-dimethyl-2,3-dihydro-1 H-indene-1-thione (DM-7HIT), which possesses a strong polar (hydroxy)-dispersive (thione) type H-bond. Upon excitation, DM-7HIT exhibits anomalous dual RTP maxima at 550 685 nm. This study found that the lowest lying excited state (S1) of...
Alkali metal sulfur redox chemistry offers promising potential for high-energy-density energy storage. Fundamental understanding of alkali reactions is the prerequisite rational designs electrode and electrolyte. Here, we revealed a strong impact cation (Li+, Na+, K+, Rb+) on polysulfide (PS) stability, reversibility, solid product passivation. We employed operando UV–vis spectroscopy to show that strongly negatively charged short-chain PS (e.g., S42–/S32–) more stabilized in electrolyte...
We report here, for the first time, experimental observation on excited-state intramolecular proton transfer (ESIPT) reaction of thiol in room-temperature solution. This phenomenon is demonstrated by a derivative 3-thiolflavone (3TF), namely, 2-(4-(diethylamino)phenyl)-3-mercapto-4H-chromen-4-one (3NTF), which possesses an -S-H···O═ H-bond (denoted dashed line) and has S1 absorption at 383 nm. Upon photoexcitation, 3NTF exhibits distinctly red emission maximized 710 nm cyclohexane with...
New Pt(II) dichloride complexes [Pt(1-iqdzH)Cl2] (2a) and [Pt(3-iqdzH)Cl2] (2b), in which idqzH = 1- or 3-isoquinolinyl indazole, were prepared by treatment of the corresponding indazoles with K2PtCl4 aqueous HCl solution. Despite their nonemissive nature, these could react excess sodium picolinate, 3-trifluoromethyl-5-(2-pyridyl) pyrazole [(fppz)H] to afford respective a b series luminescent [Pt(1-iqdz)(L∧X)] [Pt(3-iqdz)(L∧X)], where L∧X 1-iqdz (1a), 3-iqdz (1b), pic (3a, 3b), fppz (4a,...
We address the issue of low electrical conductivity observed in carbon nanotube networks using first-principles calculations structure, stability, and ballistic transport different junctions. first study covalent linkers, nitrene-pyrazine case as a model for conductance-preserving [2 + 1] cycloadditions, discuss reasons their poor performance. then characterize role transition-metal adsorbates improving mechanical coupling tunneling between tubes. show that strong hybridization d orbitals...
A tetradentate bis(pyridylpyrazolate) chelate, L, is assembled by connecting two bidentate 3-(trifluoromethyl)-5-(2-pyridyl)pyrazole chelates at the 6 position of pyridyl fragment with a phenylamido appendage. This chelate was then utilized in synthesis three osmium(II) complexes, namely, [Os(L)(CO)2] (4), [Os(L)(PPh2Me)2] (5), and [Os(L)(PPhMe2)2] (6). Single-crystal X-ray structural analyses were executed on 4 5 to reveal bonding arrangement L chelate. Phosphine-substituted derivatives are...
This work demonstrates an effective and universal strategy to improve the sluggish organosulfides (R–S<sub>n</sub>–R) for redox flow batteries by asymmetric allylsubstituted (R–S<sub>n</sub>–A).
The reorganization energies may be significantly reduced by molecular symmetry effect.
Cadmium selenide is a II–VI semiconductor model system known for its nanoparticle preparation, growth mechanism, luminescence properties, and quantum confinement studies. For the past 2 decades, various thermodynamically stable "magic-size nanoclusters (MSCs)" of CdSe have been observed, isolated, theoretically calculated. Nevertheless, none proposed structures were experimentally confirmed due to small crystal domains beyond diffraction limit. With combination nondestructive SAXS, WAXS,...
We present the strategic design and synthesis of Os(II) complexes bearing a single pyridyl azolate pi-chromophore with an aim to attain high efficiency blue phosphorescence by way localized transition. It turns out that our proposal excitation seems work well upon anchoring on such control MLCT versus pipi* (or even LLCT) transitions is more straightforward. Among titled complexes, [Os(CO)3(tfa)(fppz)] (1) [Os(CO)3(tfa)(fbtz)] (5) (tfa=trifluoroacetate,...
The oxygen reduction reaction (ORR) has been studied for decades due to its importance in fuel cells or batteries. Carbon-based materials decorated with few metal active sites are one of the options replace and reduce use Pt metals. Here, we demonstrate ORR on various intrinsically functionalized Fe/C3N4 nanotubes by density functional theory (DFT) calculations both acidic alkaline media. Most overpotentials similar regardless functionalization generally lower than those On other hand,...
One of the most critical problems in lithium–sulfur (Li–S) batteries is shuttle effect. The transfer soluble lithium polysulfides (LiPSs) from sulfur cathode to anode leads a degradation Li–S battery capacity and life cycles. Recent studies reveal that carbon-based interlayer materials introduced between can effectively improve effect problem increase In this work, different types N-doped, S-doped, N,S-codoped graphene surfaces are investigated by theoretical calculations. We find strong...
The electron-localization function plots of OCCO adsorbed on O<sub>v</sub>–CuO(111), O<sub>v</sub>–Cu<sub>4</sub>O<sub>3</sub>(202) and Cu<sub>2</sub>O(111) surfaces.
In addition to the metal-centered dd transition that is widely accepted as a dominant radiationless decay channel, other factors may also play important roles in governing loss of phosphorescence efficiency for heavy-transition-metal complexes. To conduct our investigation, we synthesized two dicarbonylruthenium complexes with formulas [Ru(CO)2(BQ)2] (1) and [Ru(CO)2(DBQ)2] (2), which cyclometalated ligands BQ DBQ denote benzo[h]quinoline dibenzo[f,h]quinoxaline, respectively. Replacing one...
This work proposes a new type of molecular machine, the single-molecule electric revolving door, which utilizes conductance dependence upon conformation as well destructive quantum interference. We perform electron transport simulations in zero-bias limit using Landauer formalism together with density functional theory. The show that open- and closed-door states, accompanied by significant variation, can be operated an external field. large on-off ratio (~10(5)) implies machine also serve...
The lithium-sulfur (Li-S) battery is one of the promising energy storage alternatives because its high theoretical capacity and density. Factors governing stability polysulfide intermediates in Li-S batteries are complex strongly affected by solvent used. Herein, reduction bond cleavage reactions calculated different environments density functional theory (DFT) methods. We investigate relationship between donor numbers (DN) as well dielectric constants (ε) system relative intermediates. Our...
We investigate quantum interference in the transport properties of porphyrin-based molecular devices, and are able to develop a minimal but qualitatively accurate model conductance based on maximally localized Wannier functions just isolated molecule. find that transmission at or near Fermi level can be engineered vary by orders magnitude response hydrogen tautomerization inner ring, recently developed experimental capability. This allows us suggest tape porphyrins act as molecular-size...
Small organic molecules based on the unnatural DNA base pair dTPT3 are designed and synthesized, among which compounds bearing thiocarbonyl group, compared with their carbonyl counterparts, show a much larger SOC integral between S1(1nπ*) T1(3ππ*) states due to appropriate energy level alignment heavy sulfur atom effect, resulting in appearance of both fluorescence phosphorescence solution solid state at room temperature.
Organic blue emitters capable of proceeding triplet–triplet annihilation (TTA) are great importance for high‐efficiency organic light‐emitting diodes (OLEDs). Herein, two deep‐blue PAPE and PAPF with diphenylanthracene (DPA) moieties linked by fluorene ether, respectively, together a single DPA model emitter PAPES synthesized characterized. Theoretical calculations indicate that the TTA mechanism these materials is energetically favorable, which evidenced platinum...
In this study, we explore the possibilities of deactivating pathways organic thione containing systems through first-principles calculations. We particularly pay attention to second lying singlet excited state, S2, due its large energy difference from lowest S1 state in sulfur-containing systems. Several theoretical models including previously synthesized thiones and strategically designed molecules are investigated search for basic conjugation unit that exhibits prospect S2 fission. Various...
In this study, B3LYP is used to calculate the decarbonylation reactions of bicyclo[2.2.1]hepta-2,5-dien-7-one (7-norbornadienone, 1) and its related extended fused aromatic analogues 2−5. On basis our results, all tend proceed synchronously expel CO, forming corresponding hydrocarbons. It found that more exothermic reaction is, less a barrier it needs overcome. Moreover, upon decrease exothermicity, structure transition state farther away from reactant, increases. The results agree well with...