A5101697208- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Quantum Dots Synthesis And Properties
- Neutrino Physics Research
- Chalcogenide Semiconductor Thin Films
- Black Holes and Theoretical Physics
- Atomic and Subatomic Physics Research
- Dark Matter and Cosmic Phenomena
- Particle Accelerators and Free-Electron Lasers
- Nanocluster Synthesis and Applications
- Medical Imaging Techniques and Applications
- Spectroscopy and Quantum Chemical Studies
- Particle Detector Development and Performance
- Silicon Nanostructures and Photoluminescence
- Copper-based nanomaterials and applications
- Natural Fiber Reinforced Composites
- Gold and Silver Nanoparticles Synthesis and Applications
- Computational Physics and Python Applications
- Advanced Cellulose Research Studies
- Nuclear physics research studies
- Epoxy Resin Curing Processes
- Photonic and Optical Devices
- Advanced NMR Techniques and Applications
- Advanced biosensing and bioanalysis techniques
Wuhan University
2008-2025
Bowling Green State University
2015-2025
Jilin University
2024
Carnegie Mellon University
2024
Ruhr University Bochum
2024
Central China Normal University
2024
Central South University
2024
China University of Geosciences
2024
COMSATS University Islamabad
2024
Budker Institute of Nuclear Physics
2024
Injection of photoexcited electrons from colloidal PbS quantum dots into TiO2 nanoparticles is investigated. The electron affinity and ionization potential dots, inferred cyclic voltammetry measurements, show strong size dependence due to confinement. On the basis measured energy levels, should transfer efficiently only for quantum-dot diameter below ∼4.3 nm. Continuous-wave fluorescence spectra transients coupled titanium dioxide are consistent with small dots. time surprisingly slow (∼100...
We report the design, fabrication, and characterization of colloidal PbSe nanocrystal (NC)-based photovoltaic test structures that exhibit an excitonic solar cell mechanism. Charge extraction from NC active layer is driven by a photoinduced chemical potential energy gradient at nanostructured heterojunction. By minimizing perturbation to levels thereby gaining insight into "intrinsic" properties charge transfer mechanism NC, we show direct correlation between interfacial level offsets device...
Internanocrystal coupling induced excitons dissociation in lead salt nanocrystal assemblies is investigated. By combining transient photoluminescence spectroscopy, grazing incidence small-angle X-ray scattering, and time-resolved electric force microscopy, we show that can dissociate, without the aid of an external bias or chemical potential gradient, via tunneling through a barrier when energy comparable to exciton binding energy. Our results have important implications for design...
A novel method is reported to create inorganically connected nanocrystal (NC) assemblies for both II-VI and IV-VI semiconductors by removing surfactant ligands using (NH4)2S. This surface modification process differs from ligand exchange methods in that no new are introduced the post-treated NC surfaces nearly bare. The detailed mechanism study shows high reactivity between (NH4)2S metal-surfactant complexes enables complete removal of seconds converts metal-rich shells into metal sulfides....
We search for evidence of a light scalar boson in the radiative decays Upsilon(2S) and Upsilon(3S) resonances: Upsilon(2S,3S)-->gammaA0, A0-->mu+mu-. Such particle appears extensions standard model, where CP-odd Higgs naturally couples strongly to b quarks. find no such processes mass range 0.212 < or = mA0 9.3 GeV samples 99 x 10(6) 122 collected by BABAR detector at SLAC PEP-II B factory set stringent upper limits on effective coupling quark A0. also limit dimuon branching fraction etab...
We present an analysis of exclusive charmless semileptonic B-meson decays based on 377 million BBbar pairs recorded with the BABAR detector at Upsilon(4S) resonance. select four event samples corresponding to decay modes B0 --> pi- l+ nu, B+ pi0 rho- and -> rho0 find measured branching fractions be consistent isospin symmetry. Assuming symmetry, we combine two B pi l nu samples, similarly rho measure BF(B0 nu) = (1.41 +- 0.05 0.07) x 10^-4 (1.75 0.15 0.27) 10^-4, where errors are statistical...
We report the first observation of electrogenerated chemiluminescence (ECL) from PbS quantum dots (QDs). Different ECL intensities are observed for different ligands used to passivate QDs, which indicates that is sensitive surface chemistry, with potential serve as a powerful probe states and charge transfer dynamics in QDs. In particular, passivation QD surfaces trioctylphosphine (TOP) increases intensity by 3 orders magnitude when compared oleic acid alone. The overlap photoluminescence...
Eliminating unwanted noise in passenger compartments of vehicles is important to automobile manufacturers. The ability reduce inside the vehicle enhances perceived value consumer, and offers a competitive advantage manufacturer. Several methods are presently employed its sources, one which uses sound-absorbing materials attached various components such as floor-coverings, package trays, door panels, headliners trunk liners. Natural fibers noise-absorbing that renewable biodegradable, making...
We report e+e−→b¯b cross section measurements by the BABAR experiment performed during an energy scan in range of 10.54 to 11.20 GeV at SLAC PEP-II e+e− collider. A total relative error about 5% is reached more than 300 center-of-mass steps, separated 5 MeV. These can be used derive precise information on parameters Υ(10860) and Υ(11020) resonances. In particular we show that their widths may smaller previously measured.Received 26 September...
The roles of solvent reorganization energy and electronic coupling strength on the transfer photoexcited electrons from PbS nanocrystals to TiO2 nanoparticles are investigated. We find that electron depends only weakly solvent, in contrast strong dependence nanocrystal–molecule system. This is ascribed larger size acceptor this system, accounted for by Marcus theory. varied changing length, aliphatic aromatic structure, anchor groups linker molecules. Shorter molecules consistently lead...
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTThickness-Controlled Synthesis of Colloidal PbS Nanosheets and Their Thickness-Dependent Energy GapsGhadendra B. Bhandari†, Kamal Subedi†, Yufan He‡§, Zhoufeng Jiang†§, Matthew Leopold†, Nick Reilly†, H. Peter Lu‡§, Alexey T. Zayak†§, Liangfeng Sun*†§View Author Information† § †Department Physics Astronomy, ‡Department Chemistry, §Center for Photochemical Sciences, Bowling Green State University, Green, Ohio 43403, United States*Email: [email...
Many optoelectronic processes in colloidal semiconductor nanocrystals (NCs) suffer an efficiency decline under high-intensity excitation. This issue is caused by Auger recombination of multiple excitons, which converts the NC energy into excess heat, reducing and life span NC-based devices, including photodetectors, X-ray scintillators, lasers, high-brightness light-emitting diodes (LEDs). Recently, quantum shells (QSs) have emerged as a promising geometry for suppression decay; however,...
Two types of nonwoven composites, uniform and sandwich structures, are produced using bagasse, kenaf, ramie, polypropylene (PP) fibers. The experimental composites include kenaf/PP (70/30), bagasse/PP (50/50), ramie/PP (70/30). kenaf/bagasse/kenaf ramie/kenaf/ramie. A comparative study these is conducted in terms mechanical properties, thermal wet properties. Composite tensile flexural properties measured a desktop tester. characterized dynamic analysis (DMA). Water absorption thickness...
Transfer of photoexcited charge from PbS nanocrystals to ligand molecules is investigated in different solvents. We find that the transfer rate increases dramatically with solvent dielectric constant. This trend accounted for by a modified Marcus theory incorporates only static effects. The choice allows significant control process. As an important example, we dispersed water exhibit rates 1000 times higher than same organic solvent. Rapid extraction will be efficient nanocrystal-based...
We perform a Dalitz plot analysis of about 100,000 Ds+ decays to K+ K- pi+ and measure the complex amplitudes intermediate resonances which contribute this decay mode. also relative branching fractions --> pi- K-. For we use 384 fb-1 data sample, recorded by BABAR detector at PEP-II asymmetric-energy e+e- collider running center-of-mass energies near 10.58 GeV.
Abstract Lead sulfide (PbS) quantum dots (QDs) hold great promise for solar energy conversion, yet their efficiency is compromised by a substantial Stokes shift that adversely affects performance in photonic devices. Here, PbS QDs are integrated within single plasmonic nanocavities, significantly mitigating shifts through Purcell enhancement of band edge emission. This approach entails bottom‐up assembly into nanoparticle‐on‐mirror structures, leading to direct emission from band‐edge...
Optical second-harmonic generation (SHG) is used as a noninvasive probe of the interfaces Si nanocrystals (NCs) embedded uniformly in an SiO2 matrix. Measurements generated SH mode verify that polarization has nonlocal dipole form proportional to (E x Delta inverted) E depends on inhomogeneities incident field E, proposed recent models based locally noncentrosymmetric dipolar response averaged over spherical NC interfaces. A two-beam SHG geometry found enhance this greatly compared...
We explore the photophysical, electrochemical, and electroluminescent properties of ionic transition metal complex [(ppy)2Ir(bpy*)](PF6) where ppyH is 2-phenylpyridine bpy* 5,5′-diaryl-2,2′-bipyridine. Single layer devices structure ITO/[(ppy)2Ir(bpy*)](PF6)/Au exhibited high stability, with half-lives on order 100 h at a bias −4 V. Long lifetimes are achieved through bulky nature aryl substituents, which serves to limit chromophore–chromophore self-quenching, 5,5′ positioning these groups...
Colloidal semiconductor nanocrystals (NCs) are emerging as promising infrared-emitting materials, which exhibit spectrally tunable fluorescence, and offer the ease of thin-film solution processing. Presently, an important challenge facing development nanocrystal infrared emitters concerns fact that both emission quantum yield stability colloidal nanoparticles become compromised when nanoparticle solutions processed into solids. Here, we address this issue by developing assembly technique...
We report measurements of B-meson decays into two- and three-body final states containing two charmed baryons using a sample 230 million Y(4S) -> B Bbar decays. find significant signals in modes, measuring branching fractions BF(B^- \Lambda_c^+ \Lambda_c^- K^-) = (1.14 +- 0.15 0.17 0.60) x 10^{-3} \Xi_c^0 \Lambda_c^-) BF(\Xi_c^0 \Xi^- \pi^+) (2.08 0.65 0.29 0.54) 10^{-5}, where the uncertainties are statistical, systematic, from fraction BF(\Lambda_c^+ p K^- \pi^+), respectively. also set...
PbS quantum dots (QDs) are functionalized using ionic liquids with thiol moieties as capping ligands. The resulting amphiphilic QD exhibit fluidlike behavior at room temperature, even in the absence of solvents. photostability QDs is dramatically improved compared to as-synthesized oleic acid-capped dispersed toluene. Detailed facts importance specialist readers published "Supporting Information". Such documents peer-reviewed, but not copy-edited or typeset. They made available submitted by...
A strategy for construction of a solid-state electrogenerated chemiluminescence (ECL) sensor based on self-assembled film core/shell structural CdSe/ZnS quantum dots (QDs) is presented in this work the first time. The surface coverage QDs about 2.2 × 1012 NPs/cm2, which level submonolayer. This QD has shown strong and efficient cathodic ECL with peroxydisulfate hydroperoxide as coreactants aqueous solution. quenching effect coreactant reveals an energy-level-related mechanism processes....