Sofer Group
Research
The Sofer group deals with the synthesis, characterization and applications of 2D layered materials including graphene, transition metal dichalcogenides (TMDs), phosphorene, silicene, germanene and other monoelemental 2D materials, MAX phases and MXene, halides and many others. Synthesis of high-quality crystals allows us to study fundamental properties of these novel materials as well as exfoliation of these intriguing materials. For this purpose, we employ various routes including mechanical, liquid as well as chemical exfoliation. Chemical functionalization further allows us to tune the properties of the materials making them suitable candidates for applications in various fields. The main focus of the applied research is on the use of 2D layered materials in energy storage and conversion including electrocatalysts, batteries or supercapacitors as well as application in nano-electronic and opto-electronic, environmental remediation and chemical catalysis.
Carbon nanomaterials – graphene and its derivatives, carbon nanotubes
- Chemie grafenu a jeho derivátů (např. fluorografen, grafan, hydroxografen)
- Chemistry of graphene and its derivatives (eg. fluorographene, graphane, hydroxygraphene)
- Graphene and carbon nanotubes based membranes and buckypapers
- Various types of carbon nanostructures including quantum dots, nanostripes, nanoplates and others
- Electrocatalysis and sensors based on graphene
- Magnetic properties of carbon nanomaterials
- Study of chemical composition and implications for electrochemical properties
- Synthesis of composite nanostructured materials
Layered pnictogens – black phosphorus, arsenic, antimony and bismuth
- The optimization of synthesis of bulk materials and their exfoliation
- Study of anisotropy – magnetic, optical and electronic properties
- Investigation of application potential – catalysis, energy storage devices (batteries)
- Covalent and non-covalent functionalization, and doping
- Synthesis of composite materials
Layered forms of silicon and germanium – silicene, germanene and their derivatives
- New synthetic methods for the preparation of silicane and germanene
- Derivatisation and protection from degradation
- Investigation of properties and application potential in various research fields
- Utilization of these materials in energy storage and conversion applications
Layered chalcogenides
- Synthesis of high-quality crystals of transition as well as post transition metal chalcogenides (MoS2, InSe…)
- Investigation of crystal growth, doping and structure-property relationships
- Synthesis of composite materials based on layered chalcogenides and carbon based materials for energy storage applications
- Novel applications in energy storage, photocatalysis, sensing, nanoelectronics and photonics
MAX phases and MXenes
- Optimization of synthesis – study of temperature regimes and stoichiometry
- Study of chemical and electrochemical exfoliation methods
- Investigation of new carbide systems, possibilities of boron and nitrogen substitution
- Study of high-temperature synthesis
- Applications in energy storage and conversion, electronic and separation methods
Applications of 2D materials
- Electrocatalysis – hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, nitrogen reduction
- Electrochemical sensors of biological compounds and pollutants
- Energy storage devices (Li and Na batteries, supercapacitors)
- Nanoelectronics and optoelectronics (light emitting diodes, solar cell, transistors, photodetectors)
Technology for Material Synthesis and processing
- Gloveboxes and Schlenk lines for inert atmosphere synthesis
- High vacuum quartz ampoule sealing line
- Various muffle and tube furnaces for synthesis in air, vacuum and controlled atmosphere up to 1700°C
- Ball milling and 3D milling apparatus for powder processing
- Electrospinning system
- Various photochemical reactor (UV-C, UV-B, UV-A, mercury lamp, visible light)
- Microwave reactor for material processing under controlled atmosphere
- Several hot wall CVD deposition systems for growth of graphene, boron nitride and chalcogenides
- Bridgeman apparatus for single crystal growth
- High pressure autoclaves for synthesis under controlled atmosphere
- Vacuum evaporation system (using thermal and e-beam evaporation)
- Rapid thermal annealing system for thermal treatment of sample under vacuum and inert atmosphere
- Spin-coating and dip-coating system
- Multizone furnaces for vapor transport crystal growth experiments
- Various centrifuge and ultra-centrifuge for material processing
- Line for coin cell battery assembling in air and under argon atmosphere
Characterization techniques
- High resolution SEM/EDS and combined SEM/FIB microscope with EDS, EBSD, EBIC, STEM, SIMS detector and TEM lamella capabilities
- Structure: X-ray diffraction including asymmetric omega scan, grazing incidence, capillary measurements, high-temperature measurements
- Dynamic light scattering for zeta potential and particle size distribution measurement
- Various electrochemical workstation for LSV, DPV, EIS, battery analysis and other measurements.
- 4-Point probe measurement system for resistivity, transport measurement and transistor and photodetector device characterisation
- Surface tension and surface energy measurement setup
- Setup for photothermal measurement
- Scanning confocal microscope
- Precise balances with 1 microgram resolution
- Thermal analysis systems: DSC/TG for -100°C to 1700°C, DSC system up to 1400°C, heat conductivity measurement by laser flash analysis, drop calorimeter, DSC/TG system combined with MS
- Physical Properties Measurement System (PPMS, 2-350K, 9T) for heat capacity, vibration magnetometry, electrical and thermal transport measurement
- UV-Vis spectrometer for transmittance measurement using integration sphere, various fibre optic UV-Vis setups for in-situ and routine spectroscopic measurement
- Photoluminescence measurement system (UV-Vis-NIR)
- Combined Raman-photoluminescence/AFM measurement system for Raman and PL mapping, combined AFM/Raman spectroscopy measurement, in-situ electrochemical measurement and variable temperature experiments (10 K – 1800 K)
- FT-IR system for measurement in FIR-MIR-NIR range in transmission, diffuse and specular reflection and variable angle ATR (diamond, germanium, silicon, zinc selenide), high and low temperature environmental cell for in-situ FT-IR measurement