We report ensemble extinction and photoluminesence spectra for colloidal CdTe quantum wires (QWs) with nearly phase-pure, defect-free wurtzite (WZ) structure, having spectral line widths comparable to the best ensemble or single quantum-dot values, to the single polytypic (having WZ and zinc blende (ZB) alternations) QW values, and to those of two-dimensional quantum belts or platelets. The electronic structures determined from the multifeatured extinction spectra are in excellent agreement with the theoretical results of WZ QWs having the same crystallographic orientation. Optical properties of polytypic QWs of like diameter and diameter distribution are provided for comparison, which exhibit smaller bandgaps and broader spectral line widths. The nonperiodic WZ-ZB alternations are found to generate non-negligible shifts of the bandgap to intermediate energies between the quantum-confined WZ and ZB energies. The alternations and variations in the domain sizes result in inhomogeneous spectral line width broadening that may be more significant than that arising from the 12-13% diameter distributions within the QW ensembles.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/acsnano.6b06091 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Why do similar 1D-polyhedron-chain copper chloride semiconductors have 2-order-distinct luminescence quantum efficiencies?
J Chem Phys
December 2024
Key Laboratory of Quantum Materials and Devices of Ministry of Education, School of Physics, Southeast University, Nanjing 211189, People's Republic of China.
The "green" copper halides with one-dimensional polyhedron chains are very interesting novel semiconductors. These weakly interacting parallel quantum wires (1D polyhedron chains) play key roles in their photophysical properties. Unlike Cs3Cu2I5, which has been much investigated, its homologous compounds Cs3Cu2Cl5 and CsCu2Cl3 remain less studied and their properties are controversial.
View Article and Find Full Text PDFHigh Molecular Conductance and Inverted Conductance Decay over 3 nm in Aminium-Terminated Carbon-Bridged Oligophenylene-Vinylenes.
J Am Chem Soc
December 2024
Department of Chemistry, University of Konstanz, 78434 Konstanz, Germany.
With the progressing miniaturization of electronic device components to improve circuit density while retaining or even reducing spatial requirements, single molecules employed as electric components define the lower limit of accessible structural width. To circumvent the typical exponential conductance decay for increasing length in molecule-based wires, topological states, which describe the occurrence of discontinuities of a bulk material's electronic structure confined to its surface, can be realized for molecules by the introduction of unpaired spins at the molecular termini. The resulting high conductance and reversed conductance decay are typically only observed for shorter molecules, as the terminal spins must be within the electronic coupling range to produce the desired effects.
View Article and Find Full Text PDFAmphiphilic Photoluminescent Porous Silicon Nanoparticles as Effective Agents for Ultrasound-Amplified Cancer Therapy.
ACS Appl Mater Interfaces
December 2024
Faculty of Physics, Lomonosov Moscow State University, Leninskie Gory 1, 119991 Moscow, Russian Federation.
This study investigates the use of photoluminescent amphiphilic porous silicon nanoparticles (αϕ-pSiNPs) as effective ultrasound (US) amplifiers for cancer sonodynamic theranostics. αϕ-pSiNPs were synthesized via a novel top-down approach involving porous silicon (pSi) films electrochemical etching, borate oxidation, and hydrophobic coating with octadecylsilane (C18), resulting in milling into nanoparticles with hydrophilic exteriors and hydrophobic interiors. These properties promote gas trapping and cavitation nucleation, significantly lowering the US cavitation threshold and resulting in selective destruction of cancer cells in the presence of nanoparticles.
View Article and Find Full Text PDFQuantum-State Renormalization in Semiconductor Nanoparticles.
ACS Nano
December 2024
Department of Chemistry and Institute of Materials Science and Engineering, Washington University in Saint Louis, Saint Louis, Missouri 63130, United States.
A single photoexcited electron-hole pair within a polar semiconductor nanocrystal (SNC) alters the charge screening and shielding within it. Perturbations of the crystal lattice and of the valence and conduction bands result, and the quantum-confinement states in a SNC shift uniquely with a dependence on the states occupied by the carriers. This shifting is termed quantum-state renormalization (QSR).
View Article and Find Full Text PDFCore-Shell Quantum Wires-Supported Single-Atom Fe Electrocatalysts for Efficient Overall Water Splitting.
Small
December 2024
College of Chemistry Engineering, Guangdong University of Petrochemical Technology, Maoming, 525000, China.
It is of great significance for the development of hydrogen energy technology by exploring the new-type and high-efficiency electrocatalysts (such as single atom catalysts (SACs)) for water splitting. In this paper, by combining interface engineering and doping engineering, a unique single atom iron (Fe)-doped carbon-coated nickel sulfide (NiS) quantum wires (NiS@Fe-SACs) is prepared as a high-performance bi-functional electrocatalyst for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Theoretical calculation and experimental results show that the addition of atomic Fe species can effectively adjust the electronic structure of sulfide, the interfacial electron transfer modulates the d-band center position, optimizing the transient state of the catalytic process and adsorption energy of hydrogen/oxygen intermediates, and greatly accelerates the kinetics of HER and OER.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!