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Semiconducting quantum dots (Q-dots) with strain-tunable electronic properties are good contenders for quantum computing devices, as they hold promise to exhibit a high level of photon entanglement. The optical and electronic properties of Q-dots vary with their size, shape, and makeup. An assortment of Q-dots has been studied, including ZnO, ZnS, CdSe and perovskites [1]. We have employed both Raman spectroscopy (to precisely determine their vibrational frequencies) and UV-VIS spectroscopy (to determine accurately their band gap energies). The electronic band structure and density of states of the ZnO and ZnS Q-dots have been investigated under strain using Density Functional Theory (DFT). The computer program SIESTA (Spanish Initiative for Electronic Simulations with Thousands of Atoms) was used to perform the DFT calculations via the linear combination of atomic orbitals (LCAO) method. The spin polarization of such systems may itself be used to encode information or influence the electronic properties of semiconducting Q-dots, which deserve special attention, as they have potential applications in lasers, photovoltaic cells, and imaging. In addition, we have investigated pristine and functionalized graphene nanoplatelets and metal oxides for sensing applications. 

Powders and films composed of tin dioxide (SnO2) are promising candidates for a variety of high-impact applications, and despite the material’s prevalence in such studies, it remains of high importance that commercially available materials meet the quality demands of the industries that these materials would most benefit. Imaging techniques, such as scanning electron microscopy (SEM), atomic force microscopy (AFM), were used in conjunction with Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) to assess the quality of a variety of samples, such as powder and thin film on quartz with thicknesses of 41 nm, 78 nm, 97 nm, 373 nm, and 908 nm. In this study, the dependencies of the corresponding Raman, XPS, and SEM analysis results on properties of the samples, like the thickness and form (powder versus film) are determined. The outcomes achieved can be regarded as a guide for performing quality checks of such products, and as reference to evaluate commercially available samples. 

Graphene nanoplatelets (GnPs) are promising candidates for gas sensing applications because they have a high surface area to volume ratio, high conductivity, and a high temperature stability. The information provided in this data article will cover the surface and structural properties of pure and chemically treated GnPs, specifically with carboxyl, ammonia, nitrogen, oxygen, fluorocarbon, and argon. Molecular dynamics and adsorption calculations are provided alongside characterization data, which was performed with Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) to determine the functional groups present and effects of those groups on the structural and vibrational properties. Certain features in the observed Raman spectra are attributed to the variations in concentration of the chemically treated GnPs. XRD data show smaller crystallite sizes for chemically treated GnPs that agree with images acquired with scanning electron microscopy. A molecular dynamics simulation is also employed to gain a better understanding of the Raman and adsorption properties of pure GnPs.