By:
On:
In: Summerstudents

Transparent conductive oxides are an important material in the photovoltaic and semiconductor industry. In the past years, Hydrogen doped Indium Oxide (IOH) has shown outstanding electrical and optical properties compared to Aluminum doped Zinc Oxide (AZO). Therefore, it has a high potential as a transparent front contact in CIGS solar cells and modules where this material is commonly used. In this project, we are investigating the properties of pulsed DC-sputtered IOH before and after an annealing on varying substrate layers to successfully implement the material in CIGS. This will help to improve the efficiency of the devices due to a better management of the sunlight.     TheRead More →

By:
On:
In: Summerstudents

  “We live in the silicon era.” Silicon is still by far the most widely used PV material. The latest 2017 world record solar cell for Silicon heterostructures (HIT) achieved an ECE of 26.63%. At its hearth, the materials used are amorphous-Silicon hydrogen passivated and crystalline silicon (aSi:H-cSi). Such an interface showcases interesting electrical and electro-chemical properties. Evidence of its potential capabilities for reducing defect densities and their photon absorption with its two energy band gaps have been observed. Both phenomena, if correctly engineered, are known to help increase efficiency[1]. Our curiosity driven investigation by surface photovoltage (SPV) spectroscopy and by SPV transient measurements mayRead More →

By:
On:
In: Summerstudents

SnWO4 thin film photoelectrodes for solar water splitting Solar water splitting offers a solution for solar energy storage problem, since the generated hydrogen can be stored as a renewable fuel. However, a suitable photoelectrode material for water oxidation reaction is still elusive. The reason for this is that the semiconducting materials have to meet the stringent requirements. For example, the elements of the electrode have to be earth-abundant and allow stability in aqueous solution. Furthermore, the photoelectrode has to absorb most of the visible spectrum of the sun to ensure a high solar-to-hydrogen efficiency. In this work, a new promising n-type semiconductor α-SnWO4 was examined.Read More →

By:
On:
In: Summerstudents

Why it’s important? Development of photovoltaic and other energy materials requires a lot of experiments and comprehensive processing of data is vital for successful research in this fields.  Unfortunately, sometimes measurement systems software couldn’t provide all necessary features, e.g. combining data from different samples, excluding inaccurate data, etc. That’s why we are currently developing complex data analysis program for state-of-the-art Hall Measurement system. Program itself is complex project in Python high-level programming language with a lot of different plotting and calculation options, such as calculating charge carrier concentration, mobility and many other parameters. It’s also possible to analyze AC field measurements, which is useful forRead More →

By:
On:
In: Summerstudents

Superconductive materials, usually niobium, are used in cavities of particle Accelerators.  In order to measure some key parameters of niobium, such as surface resistance, critical magnetic field and penetration depth, at radio frequency( as particle accelerators are working in that range) a test setup is used, which is called as quadrupole resonator.  A superconducting sample is mounted to the test setup, quadrupole resonator creates the desired frequency and here with the magnetic field. In order to calculate those key parameters, temperature and dissipated power are measured. Later, those measurements are used to calculate and determine the key parameters with the help of MatLab. My projectRead More →

By:
On:
In: Summerstudents

Superconducting radio-frequency photoelectron injectors (SRF photoinjectors) are promising electron sources for high brightness accelerators with high average current and short pulse duration. The task of the GunLab facility is to ensure safe operation of the SRF gun, check the theoretical model for the beam dynamics by measurements and to find an optimum working point for BERLinPro. Data acquisition and analysis for GunLab is important to have a better understanding of the gun performance and the efficiency of the diagnostic tools. During this two –month research work, different experimental measurements were made for the dipole and quadrupole magnets and then coding, analyzing data with Matlab softwareRead More →

By:
On:
In: Summerstudents

Nafion® is the most used polymer in Proton Exchange Membrane Fuel Cells (PEMFC) that work in the temperature range of 80-130 ºC. The PEMFC efficiency is controlled by a Nafion’s thermal transition, labeled α (Tα ~ 110 ºC). Above the α-transition, irreversible modifications of the Nafion chemical interactions is responsible for a dramatic degradation of Nafion proton conductivity that can lead to the fuel cell collapse. Such transition has been rarely studied by infrared spectroscopy (IR). The IR would allow understanding the specific interactions among Nafion’s functional groups underlying α-transition. Thus, this investigation would help boosting PEMFC technology as well as advancing the development high-performance polymerRead More →

By:
On:
In: Summerstudents

    Figure 1 :  The mini solar module after scribing.   The laser scribing, which means digging lines within the layers of the solar cells, is a significant process within the fabrication scheme for solar cells modules. Scribing is done in order to contact the cells within the module, upscale the area of ​​these manufactured modules for industrial applications and save the efficiency in the meantime. My project is concerned with the scribing of the absorber material layer of CIGS thin film solar cells. This involves optimization of the parameters of the lasers beams, pico and nanosecond ones , and comparing, qualitatively and quantitatively,Read More →

By:
On:
In: Summerstudents

Theoretical Characterization of Nitrogen-Doped Graphene Oxide Quantum Dots Materials capable of catalyzing water splitting reactions when irradiated by sunlight show considerable promise as a hydrogen fuel source. These photocatalysts are suitable for large scale hydrogen production, since the process requires only water,  solar energy and the catalyst itself. One such material is graphene oxide (GO) which is particularly interesting because its properties can be easily tuned to enhance its efficiency. In this project, we investigate how different functionalization patterns affect the photocatalytic activity of nitrogen-doped GO by calculating theoretical IR, UV and X-ray spectra for a number of suitable model systems (shown above). As theRead More →

By:
On:
In: Summerstudents

My project is to relate the heat treatment conditions of Al8Co17Cr17Cu8Fe17Ni33 alloy (which is called a “High Entropy Alloy”) with the hardness of it. It is even interesting for me too because these alloys present a new class of materials that present novel phase structures and properties, and it has not much usage area at the moment. So there is a huge world waiting to be discovered. So, what is this HEA thing? There is no universally agreed-upon definition of a HEA but the most agreed one is alloys containing at least 5 elements with concentrations between 5 and 35 atomic percent. In addition, laterRead More →