We study the mutual effects of photoinduced processes (irradiation effects) and plasmonic emission enhancement in close-packed CdSe/ZnS colloidal quantum dots in the vicinity of gold metallic nanoparticles with two significantly different size distributions. For this we examine the impact of the heat generated by the metallic nanoparticles, the strength of plasmonic field enhancement, and the rate of energy transfer from the quantum dots to metallic nanoparticles in the presence of a laser field with low and moderate intensities. Our results show that the interplay between the photophysics of the quantum dots and their plasmonic emission enhancement is significantly pronounced when the metallic nanoparticles are large. In such a case we observed large suppression of photoinduced fluorescence enhancement (PFE). For smaller metallic nanoparticles the results suggest mostly an overall time-independent suppression of the quantum dots’ emission with no significant impact on PFE.

In this paper, we present ink-jet printing as an attractive alternative to lithography and etching methods for the development of multi-filamentary YBa2Cu3O7-δ coated conductors. Our research is mainly focused on the study of the influence of rheological parameters on the printability of water-based inks in order to produce superconducting patterns on SrTiO3 and CeO2-La2Zr2O7-Ni5at%W substrates. An aqueous YBCO precursor ink with a total metal ion concentration of 1.1 mol/L with a viscosity of 6.79 mPa s and a surface tension of 67.9 mN/m is developed. Its printing behavior using several ink-jet printing devices is verified using a camera with strobed illumination to quantify droplet velocity and volume. After optimization of the deposition parameters, YBCO tracks with different dimensions could be printed on both types of substrates. Their shape and dimensions were determined using optical microscopy and non-contact profilometry, showing 100-200 nm thick and 40-200 µm wide tracks. Finally, resistivity measurements were performed on the widest tracks on SrTiO3 showing a clear drop in the resistivity starting from 88.6 K with a ∆Tc of 1.4 K.

The sand of glaciolacustrine origin is offered as a major component of the backfill in repositories for solid or solidified low and intermediate level waste (LILW). Clinoptilolite, hematite, and magnesium oxide are offered as additives for increasing of sorption. In this work was carried investigation of sorption properties of sand, clinoptilolite, hematite and magnesium oxide and mixtures of sand with these mineral additives.

Papers in the Appendix were published in electronic format as Volume 1534

High quality dilute nitride subcells for multijunction solar cells are achieved using GaInNAsSb. The effects on device performance of Sb composition, strain and purity of the GaInNAsSb material are discussed. New world records in efficiency have been set with lattice-matched InGaP/GaAs/GaInNAsSb triple junction solar cells and a roadmap to 50% efficiency with lattice-matched multijunction solar cells using GaInNAsSb is shown.

In this work, we study CdTe thin films used in CdTe/CdS solar cells with a substrate configuration, which allows for better control in forming the junction, and the possibility for using flexible non-transparent substrates. We studied the properties of CdTe films grown at 450° and 550°C, with and without a CuxTe layer, and before and after CdCl2 treatment. We analyzed the structural and electro-optical properties using electron backscatter diffraction (EBSD), cathodoluminescence (CL) and X-ray diffraction (XRD), and investigated how the film structure, stress, and defect structure changes with the different growth conditions.

Two growth techniques - antimony exposure and graded growth, were proposed to achieve the control over the morphology and optical properties of self-assembled InAsSb/InGaAs/InP nanostructures. By exposing the surface of InGaAs buffer layer to trimethylantimony precursor before the growth of InAsSb nanostructures, the surface/interface energy in the system is reduced, while the strain energy in the system is enhanced. This leads to a change of island shape from dot structure to wire structure. By using a higher initial mole fraction of trimethylantimony precursor during the graded growth of InAsSb, more Sb can be incorporated into the InAsSb islands despite the same Sb mole fraction averaged over the graded growth. This also results in a shape change from dot to wire structure. As a result of their shape change, photoluminescence from the InAsSb nanostructures shows different polarization characteristics.

Thin films of ZnO co-doped with lithium and phosphorus were deposited on sapphire substrates by RF magnetron sputtering. The films were sequentially deposited from ultra pure ZnO and Li3PO4 solid targets. Post deposition annealing was carried using a rapid thermal processor in O2 and N2 at temperatures ranging from 500 °C to 1000 °C for 3 min. Analyses performed using low temperature photoluminescence spectroscopy measurements reveal luminescence peaks at 3.359, 3.306, 3.245 eV for the co-doped samples. The x-ray diffraction 2θ-scans for all the films showed a single peak at about 34.4° with full width at half maximum of about 0.17°. Hall Effect measurements revealed conductivities that change from p-type to n-type over time.

In this study, Pd thin film is used as catalyst to grow epitaxial InAs nanowires on GaAs(111)B substrate in a metal-organic chemical vapor deposition reactor to explore the growth mechanism and the effects of non-gold catalysts in the growth of III-V epitaxial nanowires. Through detailed morphological, structural and chemical characterization using scanning and transmission electron microscopy, it is found that defect-free zinc-blende structured epitaxial InAs nanowires are grown along the <110> directions with four {111} sidewall facets forming a diamond shaped cross-section. Furthermore, the interface between the nanowire/catalyst is found to be the uncommon {113} planes. It is anticipated that these zinc-blende structured InAs nanowires are grown via the vapor-liquid-solid mechanism. The defect-free nature of these nanowires arises from the non-<111> growth direction and non-{111} nanowire/catalyst interface.

Metallic silver nanoparticles (NPs) have extensively been used in the treatment of disease and purification and heralded the ‘first wave’ of disinfection science, the ‘second wave’ being the nanocomposite of metal-doped TiO2. Recent advances in engineered surfaces have enabled ultrahigh surface area and rapid sterilization via using metal-organic frameworks (MOFs) as the ‘third wave’ disinfectant. MOFs offer the same advantages as colloids but also have ultra high surface area, long term persistence and ultra low doses, applied for water purification.

Highly ion-conductive Li6PS5Cl Li-argyrodites were prepared through a high energy ball milling. Electrical and electrochemical properties were investigated. Ball-milled compounds exhibit a high conductivity of 1.33×10−4 S/cm with an activation energy of 0.3-0.4 eV and an electrochemical stability up to 7V vs. lithium. These results are obtained after only 10 hours of milling and with no additional heat treatment.

To validate the use of the Li6PS5Cl-based solid electrolyte, all-solid-state batteries using LiCoO2 and Li4Ti5O12 as active material have been realized. The optimization of the electrode composition led to a maximum of 46 and 27 mAh per gram of composite for LiCoO2 and Li4Ti5O12-based half-cells respectively. The assembled all-solid-state LiCoO2 / Li6PS5Cl / Li4Ti5O12 battery presents a sustainable reversible capacity of 27 mAh per gram of active material and a coulomb efficiency close to 99%.

As an application to the nanoemitter, we investigated the nanofabrication of diamond-like carbon (DLC)-dot arrays by room-temperature curing imprint-liftoff (RTCIL) method using aluminum mask. The DLC film which has excellent properties similar to diamond properties was used as the patterning material. A polished glass like carbon (GC) was used as a mold material. The polysiloxane in the state of sticky liquid at room temperature and stable in air exhibits a negative-exposure characteristics. Therefore, the polysiloxane was used as electron beam (EB) resist and oxide mask material in EB lithography, and also used as RTC-imprint resist material. An aluminum was used as oxide metal mask material of liftoff. We have fabricated the GC mold of dot arrays with 5 µm-square and 500 nm-height. We carried out the RTCIL process using the GC mold under the following optimum imprint conditions: 0.5 MPa-imprinting pressure and 5 min- holding time. Aluminum film on the imprinted polysiloxane was prepared by vacuum evaporation method and its thickness is 20 nm. Finally, the polysiloxane patterns were removed with acetone and aluminum mask patterns were fabricated. We found that the maximum etching selectivity of aluminum film against DLC film was as high as 35, which was obtained under an ion energy of 400 eV. Then we processed the patterned aluminum on DLC film with an ECR oxygen ion shower. We fabricated DLC-dot arrays with 5 µm-square and 400 nm-height with an aspect ratio of 0.08.

We have investigated the counter intuitive phenomenon of inserting a metal oxide layer to improve hole injection or extraction in organic semiconductor devices using ultraviolet photoemission, x-ray photoemission, and inverse photoemission spectroscopy (UPS, XPS and IPES). We observed that metal oxides, such as MoO3, substantially increase the work function when deposited on indium-tin-oxide (ITO). The increase lifts up the highest occupied molecular orbital (HOMO) of the hole transport layer, therefore reduces the energy barrier between the HOMO and the Fermi level of the anode. The uplift creates an interface band bending region that results in a drift electric field that encourages the collection of holes at the anode. The optimum thickness for the oxide layer is estimated to be 2 nm. We have also investigated the effects of ambient or O2 exposure of MoO3. We observed that while most of the electronic energy levels of the oxide remained largely intact, the work function reduction was significant. This opens a way for optimal energy level alignment by modifying the work function through exposure. Furthermore, we observed that the work function reduction by exposure could be reversed by proper annealing of the sample in vacuum. The investigations therefore point to manipulate the interface electronic structure and charge injection/extraction by thin metal oxide films.

The paper presents a comparative study of the photoluminescence (PL) and Raman scattering spectra of core-shell CdSe/ZnS quantum dots (QDs) in nonconjugated states and after the conjugation to the anti-human papilloma virus (HPV), HPV 16-E7, antibodies. All optical measurements are performed on the dried droplets of the original solution of nonconjugated and bioconjugated QDs located on the Si substrate. CdSe/ZnS QDs with emission at 655 nm have been used. PL spectra of nonconjugated QDs are characterized by one Gaussian shape PL band related to the exciton emission in the CdSe core. PL spectra of bioconjugated QDs have changed essentially: the core PL band shifts into the high energy spectral range (“blue” sift) and becomes asymmetric. A set of physical reasons has been proposed for the “blue” shift explanation of the core PL band in bioconjugated QDs. The variation of PL spectra versus excitation light intensities has been studied to analyses the exciton emission via excited states in QDs. Finally the PL spectrum transformation for the core emission in bioconjugated QDs has been attributed to the electronic quantum confined effects stimulated by the electric charges of bioconjugated antibodies.

Hydrogels consisting of the conducting polymer PEDOT:PSS and the biopolymer gellan gum (GG) were characterized using electrical, mechanical and rheological methods. Compression testing and rheological analysis showed that the gels weakened with increasing PEDOT:PSS content. In contrast, the increasing PEDOT:PSS content resulted in an increasing electrical conductivity.

Thin-films of magnetic nanoparticles (MNPs) with high coercivities are deposited onto surfaces for use in data storage applications. This usually requires specialist clean-room facilities, sputtering equipment and high temperatures to achieve the correct crystallographic phases. One possible cheaper and more environmentally friendly alternative could be to use biomolecules. Many biomineralization and biotemplating molecules have been identified that are able to template a wide range of technologically relevant materials using mild, aqueous chemistry under physiological reaction conditions. Here, we have designed a dual affinity peptide (DAP) sequence to template MNPs onto a surface. One end of the DAP has a high binding affinity for SiO2 and the other for MNPs of the L10 phase of CoPt, a high coercivity magnetic material. Images of the biomineralized substrates show that nanoparticles of CoPt are localized onto the areas that were functionalized with the biotemplating DAP. Magnetic force microscopy (MFM) plots of the biotemplated nanoparticles show that there is magnetic contrast on the patterned surface.