A5046898233- Ionic liquids properties and applications
- Advancements in Battery Materials
- Electrochemical Analysis and Applications
- Graphene research and applications
- 2D Materials and Applications
- Material Dynamics and Properties
- Thermodynamic properties of mixtures
- Supercapacitor Materials and Fabrication
- Advanced Battery Materials and Technologies
- Inorganic and Organometallic Chemistry
- Surfactants and Colloidal Systems
- Ga2O3 and related materials
- Boron and Carbon Nanomaterials Research
- Photochemistry and Electron Transfer Studies
- Advanced Battery Technologies Research
- Laser Material Processing Techniques
- Block Copolymer Self-Assembly
- Extraction and Separation Processes
- Nanowire Synthesis and Applications
- Strong Light-Matter Interactions
- Nanopore and Nanochannel Transport Studies
- Advanced DC-DC Converters
- Adsorption, diffusion, and thermodynamic properties of materials
- Chemical and Physical Properties in Aqueous Solutions
- Nonlinear Optical Materials Studies
Kansas State University
2018-2022
Institute of Mechanics
2021
University of Chinese Academy of Sciences
2021
Xiamen University of Technology
2020
University of Central Florida
2020
Texas Tech University
2014-2018
Lubbock Christian University
2015-2018
Shanghai Maritime University
2017
Pennsylvania State University
2016
Xiamen University
2008-2013
Hexagonal boron nitride (hBN) with a single isotope have many enhanced physical, thermal and optical properties compared to the most common hBN natural distribution of (19.9 at. % 10B 80.1 11B). These property differences can significantly improve device performance in applications, such as neutron detectors, nanoscale electronics, components. In this study, new method for growth large-scale, high-quality monoisotopic crystals, i.e., h10BN h11BN, was developed. crystals were grown using...
The branched ionic liquids (ILs) 1-(iso-alkyl)-3-methylimidazolium bis[(trifluoromethane)sulfonyl]amide ([(N – 2)mCN-1C1im][NTf2] with N = 3–7) were synthesized and their physicochemical properties characterized compared the of linear ILs 1-(n-alkyl)-3-methylimidazolium ([CNC1im][NTf2] 3–7). For 4–7, density IL [(N 2)mCN–1C1im][NTf2] is same as that its analogue [CNC1im][NTf2] within standard uncertainty measurements. In case 3 [1mC2C1im][NTf2]/[C3C1im][NTf2] pair, 0.13% higher than IL. a...
In this work, a series of imidazolium-based ionic liquids with varying functionalities from aliphatic to aromatic groups and fixed anion, bis[(trifluoromethane)sulfonyl]amide, were investigated. The imidazolium cations included 1-heptyl-3-methylimidazolium, 1-(cyclohexylmethyl)-3-methylimidazolium, 1-benzyl-3-methylimidazolium, 1,3-dibenzylimidazolium, 1-(2-naphthylmethyl)-3-methylimidazolium. Structure–property relationships investigated regarding the substituent effects on cation,...
A novel nanoarchitectured Sn–Sb–Co alloy electrode is reported, which was prepared by direct electrodeposition on a Cu nanoribbon array in order to target the rapidly fading capacity and poor rate-capability issues of Sn based materials for Li-ion batteries. The SEM images indicate three-dimensional (3D) with an structure. Electrochemical measurements show that 3D Sn54Sb41Co5 exhibits reversible as high 512.8 mA h g−1 at 0.2 C (1 = 650 g−1) after 150 cycles. Furthermore, anode can deliver...
A series of branched ionic liquids (ILs) based on the 1-(iso-alkyl)-3-methylimidazolium cation from 1-(1-methylethyl)-3-methylimidazolium bistriflimide to 1-(5-methylhexyl)-3-methylimidazolium and linear ILs 1-(n-alkyl)-3-methylimidazolium 1-propyl-3-methylimidazolium 1-heptyl-3-methylimidazolum were recently synthesized their physicochemical properties characterized. For with same number carbons in alkyl chain, IL was found have density but higher viscosity than one. In addition,...
We study shallow and deep levels in carbon-doped hexagonal boron nitride crystals precipitated from a molten metal solution high-temperature furnace. Reflectance photoluminescence under ultraviolet excitation are complemented by spatially resolved experiments means of scanning confocal micro-photoluminescence setup operating the ultraviolet. Isotopically controlled carbon doping does not induce any energy shift well-known deep-level emission at 4.1 eV. Our detailed characterization series...
The presence of metastable Bernal stacking boron nitride is verified by combining second harmonic generation (SHG) and photoluminescence (PL) spectroscopy. scanning confocal cryomicroscope, operating in the deep-ultraviolet range, shows a one-to-one correlation between inversion symmetry breaking probed SHG detection an intense PL line at ∼6.035 eV, specific signature noncentrosymmetric stacking. coherent character phase crystals demonstrated two-photon excitation Direct indirect excitons...
The local structure and intermolecular dynamics of an equimolar mixture benzene 1,3-dimethylimidazolium bis[(trifluoromethane)sulfonyl]amide ([dmim][NTf2]) were studied using molecular (MD) simulations femtosecond optical Kerr effect (OKE) spectroscopy. OKE spectrum the benzene/[dmim][NTf2] at 295 K was analyzed by comparing it to ideal obtained taking volume-fraction weighted sum spectra pure liquids. experimental is higher in frequency broader than that spectrum. These spectral differences...
The principal difference between 1-benzyl-3-methyl-imidazolium triflimide [BzC1im][NTf2] and an equimolar mixture of benzene dimethylimidazolium [C1C1im][NTf2] is that in the former moieties are tied to imidazolium ring, while latter they move independently. We use femtosecond optical heterodyne-detected Raman-induced Kerr effect spectroscopy (OHD-RIKES) molecular simulations explore some properties these two systems. spectra show small differences spectral densities; also very similar...
The nature of point defects in hexagonal boron nitride (hBN) is current interest for the potential to alter its optical and electrical properties. strong interaction between neutrons boron-10 isotope makes neutron irradiation a controllable way introduce hBN. In this study, we perform Raman spectroscopy, photoluminescence, electron paramagnetic resonance (EPR), optically detected magnetic (ODMR) characterization neutron-irradiated monoisotopic (hBN with single isotope) 10B- 11B-enriched hBN...
We report a study of polymorphic boron nitride (BN) samples. interpret the photoluminescence (PL) line at $6.032\ifmmode\pm\else\textpm\fi{}0.005\phantom{\rule{0.16em}{0ex}}\mathrm{eV}$ that can be recorded 8 K in $s{p}^{2}$-bonded BN as being signature excitonic fundamental bandgap Bernal (bBN) [or graphitic (gBN)] polymorph. This is determined by advanced PL measurements combined with x-ray characterizations on pure hexagonal (hBN) and crystal samples, later compared theoretical...
The intermolecular dynamics of dilute solutions CS2 in 1-alkyl-3-methylimidazolium bis[(trifluoromethane)sulfonyl]amide ([CnC1im][NTf2] for n = 1–4) were studied at 295 K using femtosecond optical Kerr effect (OKE) spectroscopy. OKE spectra the CS2/ionic liquid (IL) mixtures analyzed an additivity model to obtain contribution spectrum from which information about modes these was gleaned. is lower frequency and narrower than that neat CS2, as found previously [C5C1im][NTf2]. Moreover, a...
Atomistically detailed molecular dynamics simulations were used to investigate the temperature dependence of specific volume, dynamic properties, and viscosity linear alkyl chain ([CnC1Im][NTf2], n = 3-7) branched ([(n - 2)mCn-1C1Im][NTf2]) ionic liquids (ILs). The trend glass transition (Tg) values obtained in as a function length cations was similar seen experiments. In addition, system relaxation behavior determined from diffusion coefficient, rotational time, close Tg observed follow...
The authors demonstrate a method for transverse writing of optical waveguides in crystalline silicon wafer using nanosecond laser with shaped beam profile that is formed by pair cylindrical lenses. In contrast to traditional methods, this avoids forming asymmetric waveguide profiles. Both straight and curved are written nearly circular guide found support single-mode propagation 1550 nm wavelength light. loss also measured.
A comparative study of the intermolecular dynamics CS2 in monocationic and dicationic ionic liquids (ILs) was performed using optical heterodyne-detected Raman-induced Kerr effect spectroscopy (OHD-RIKES). The reduced spectral densities (RSDs) mixtures 1-alkyl-3-methylimidazolium bis[(trifluoromethane)sulfonyl]amide ([CnC1im][NTf2] for n = 3-5) 1,2n-bis(3-methylimidazolium-1-yl) alkane ([(C1im)2C2n][NTf2]2 were investigated as a function concentration at 295 K. An additivity model used to...
The low-frequency (0–450 cm–1) Kerr spectra of 1-benzyl-3-methylimidazolium bis[(trifluoromethane)sulfonyl]amide ([BnzC1im][NTf2]) and 1,3-dibenzylimidazolium ([(Bnz)2im][NTf2]) 2:1 1:1 mixtures benzene in 1,3-dimethylimidazolium ([C1C1im][NTf2]) were measured by the use optical heterodyne-detected Raman-induced effect spectroscopy (OHD-RIKES). Surprisingly, line-shape intermolecular part height-normalized spectrum is same for both C6H6/[C1C1im][NTf2] mixtures, which may be a signature local...
We report hyperspectral microscopy in ${sp}^{2}$-bonded boron nitride polytypes with a simultaneous inspection of the photoluminescence signal UV-C and UV-B spectral ranges. By comparing two different extracted from same polycrystalline sample, we reveal that well-known ``4 eV defect'' does not emit at energy for $AB$ $A{A}^{\ensuremath{'}}$ stackings. The zero-phonon line is either 4.14 or 4.16 noncentrosymmetric stacking, instead usual 4.09 stacking. Our results open way characterization...