|
The CoulTCell is a coulometric titration setup for measurements of oxygen nonstoichiometric properties of materials at high temperatures, and in different partial pressure of oxygen. The output of these experiments can be used for the investigation of the redox behavior of nonstoichiometric materials. The system consist of two parts; the cell and the instruments package, to be aquired together or separately. The cell is brass and alumina made, two 8% mol partially stabilized YSZ electrolytes, S-type thermocouple, Swagelok valves and bulkheads and 8mm water cooling- in and outlets. Accessing sample is easy by detaching the outer tube by unscrewing 4 short bolts. Equipped with several spare crucibles. The design is improved version of equipment resulting from years of research development and experience by research fellows Dr. Egil Bakken and Mehdi Pishahang under supervision of professors Svein Stølen and Truls Norby at the University of Oslo. The instruments package consist of precission power source and a multimeter, controlled by a computer software. The instruments are enclosed in a compact casing, connecting to the computer wuth USB cable and to the cell with BNC cables (cables included). The system offers a cost-effective alternative to developing and building your own cell for studies, characterization and testing of inorganic materials for purposes like fuel cell components, membrane materials, chemical-looping oxygen carriers, etc. All units are tested and validated with strict requirements. Brief description of the cell The sample is placed in an alumina crucible, hanging from the sample holder rods by platinum wires, deep inside the furnace. The sealing system consisting of a gasket and front flange couplings are placed on the top of the setup and above the furnace. Water cooling system keeps the joints and sealing components protected. By giving feedback to the furnace power supply, the S-type thermocouple implanted into the setup controls the actual temperature of the sample and the solid electrolytes. The gas inlet and outlet (Swagelok bulkheads) can be used to flush the entire setup with the desired gases (e.g. air, O2, or N2). Oxygen pump solid electrolyte sucks oxygen from the setup, and therefore the sample, while oxygen sensor solid electrolyte monitors the changes of the oxygen partial pressure simultaneously. The instrument package and software supply and measure the voltage and current of the solid electrolytes. The interface between the electronic controllers and the user is applicable by the software which shows the state of the system graphically and logs the output every 5 seconds. Desired gases can be fed in one or both of the solid electrolytes, providing the chance to adjust the chemical leakage. Suitable for >4 cm diameter, Cell specifications Outer tube diameter: 30mm Instrument package specifications Instruments Keithley 2000 DMM with scan card, Keithley 2401 SMU Additional equipment required
|
|
||||||||
