Search results for " Thin Film"

Stabilizing spin spirals and isolated skyrmions at low magnetic field exploiting vanishing magnetic anisotropy

2018

Skyrmions are topologically protected non-collinear magnetic structures. Their stability is ideally suited to carry information in, e.g., racetrack memories. The success of such a memory critically depends on the ability to stabilize and manipulate skyrmions at low magnetic fields. The non-collinear Dzyaloshinskii-Moriya interaction originating from spin-orbit coupling drives skyrmion formation. It competes with Heisenberg exchange and magnetic anisotropy favoring collinear states. Isolated skyrmions in ultra-thin films so far required magnetic fields as high as several Tesla. Here, we show that isolated skyrmions in a monolayer of Co/Ru(0001) can be stabilized down to vanishing fields. Eve…

DESIGN, SYNTHESIS AND ATOMIC/ELECTRONIC STRUCTURAL ANALYSIS OF HYBRID HALIDE PSEUDO-PEROVSKITES: PERSPECTIVES AND OPEN ISSUES FOR NOVEL THERMOELECTRI…

2022

Thermochromic Thin Films: Synthesis, Properties and Energy Consumption Modelling

2013

Thermochromic materials such as vanadium dioxide have been postulated for use in “SMART” windows for a number of years. Such windows work by exploiting a structural phase change from an infra-red transmissive state to a infra-red reflective state. Significant challenges still remain before such materials will be able to find wide spread use. In this mini review we discuss the nature of this thermochromic transition with reference to the latest research work in the field. We pay particular attention to challenges such as film colouration, transition temperature, and transition hysteresis. We describe the most up to date strategies for addressing these challenges, considering advanced synthes…

Electrodeposition and Photo-electrochemical behaviour of CIGS Thin Films and Nanowires arrays for Solar Cell

2013

Electrodeposition and Photoelectrochemical Behaviour of CIGS Thin Films and Nanowire Arrays for Solar Cells

2013

CIGS Thin Film by One-Step Electrodeposition Deposition for Solar Cells

2013

Nanostructured materials for solar cells: electrochemical fabrication and characterization

2011

Ni/NiO thin film Sensors for Mercury ions detection by Square wave anodic stripping voltammetry

2018

Square wave anodic stripping voltammetry (SWASV) is considered a very interesting electrochemical method for heavy metals detection in comparison to conventional techniques [1]. The main features of this technique are the high sensitivity and reproducibility (standard deviation lower than 5%), besides, the limit of detection is in the ppb level so is comparable with standard techniques such as AAS or ICP, the instrumentation is very inexpensive and easy to use and the detection time is very low. Among heavy metals, mercury is one of the most toxic for both environment and humans. In fact, it may cause serious health problems to brain, kidney and DNA. The concentration limit imposed by US En…

The origin of slow electron recombination processes in dye-sensitized solar cells with alumina barrier coatings

2004

We investigate the effect of a thin alumina coating of nanocrystalline TiO2 films on recombination dynamics of dye-sensitized solar cells. Both coated and uncoated cells were measured by a combination of techniques: transient absorption spectroscopy, electrochemical impedance spectroscopy, and open-circuit voltage decay. It is found that the alumina barrier reduces the recombination of photoinjected electrons to both dye cations and the oxidized redox couple. It is proposed that this observed retardation can be attributed primarily to two effects: almost complete passivation of surface trap states in TiO2 that are able to inject electrons to acceptor species, and slowing down by a factor of…

Self-organization and nanostructural control in thin film heterojunctions.

2013

In spite of more than two-decades of studies of molecular self-assembly, the achievement of low cost, easy-to-implement and multi-parameter bottom-up approaches to address the supramolecular morphology in three-dimensional (3D) systems is still missing. In the particular case of molecular thin films, the 3D nanoscale morphology and function are crucial for both fundamental and applied research. Here we show how it is possible to tune the 3D film structure (domain size, branching, etc.) of thin film heterojunctions with nanoscale accuracy together with the modulation of their optoelectronic properties by employing an easy two-step approach. At first we prepared multi-planar heterojunctions w…