Wyniki wyszukiwania - BazTech

Ograniczanie wyników

2 Materials Science Poland

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: electrochemical gas sensor

Sortuj według:

Ogranicz wyniki do:

Synthesis of ceria-based nanopowders suitable for manufacturing solid oxide electrolytes

Dudek M., Mróz M., Zych Ł., Drożdż-Cieśla E.

Materials Science Poland

2008

Vol. 26, No. 2

319--329

Co-precipitation method and hydrothermal synthesis were used to fabricate nanopowders of pure CeO2 and singly or co-doped ceria materials in the CeO2-Sm2O3-Y2O3 or CeO2-Gd2O3-Sm2O3 systems. All sintered powders and samples were found to be pure CeO2 and ceria-based solid solution of fluoritetype structure. The surface areas of CeO2-based nanopowders were measured by the one-point BET method. The morphologies of powders were observed by means of transmission electron microscopy. Particle sizes of ceria powders synthesised by the hydrothermal method ranged from 9 to 15 nm, the particle sizes of powders calcined at 800 oC ranged from 13 to 26 nm. The TEM observations indicated that all CeO2-based powders consisted of isometric in shape and agglomerated particles. Scanning electron microscope was used to observe the microstructure of the sintered samples. Electrical conductivity was studied by the a.c. impedance spectroscopy in the temperature range 200-700 oC. The oxygen transference number was determined from EMF measurements of oxide galvanic cells. It was found that codoped ceria materials such as Ce0.8Sm0.1Y0.1O2 or Ce0.85Gd0.1Sm0.05O2 seem to be more suitable solid electrolytes than singly-doped ceria Ce1-xMxO2 (M - Sm, Gd, Y, x = 0.15 or 0.20) for electrochemical devices working in the temperature range 600-700 oC.

Solid-state electrochemical gas sensors

Jasiński P.

Materials Science Poland

2006

Vol. 24, No. 1

269--278

Various types of solid-state electrochemical gas sensors are presented. The sensing mechanism and examples of potentiometric, amperometric and electrocatalytic sensors are described. The possibility of multi-gas detection in the case of amperometric and electrocatalytic sensors is characterized. The principle of operation of the wide-band oxygen sensor, combining the potentiometric and amperometric modes, is presented.