scholarly journals Synthesis of Mesoporous Gadolinium Doped Ceria - Platinum Composite

2012 ◽  
Vol 1384 ◽  
Author(s):  
Hoi Yung ◽  
Kwong-Yu Chan ◽  
Frank Leung-Yuk Lam

ABSTRACTOxygen reduction in SOFC cathodes has long been the rate determining step in SOFC operations, mixed ionic-electronic conductors (MIECs) and/or forming composite between cathode and electrolyte materials have been common strategies in order to aid the cathode kinetics. We demonstrate here a viable synthesis route to impregnate mesopores with high loading of platinum towards a mesoscale bicontinuous material that composed of channels of a fast ionic conductor, i.e. gadolinium doped ceria (GDC) intertwined with channels of a good electronic conductor, i.e. Pt. This highly structural composite material holds the promise of a high performing cathode in SOFC.

Four classes of solid ionic conductors may be distinguished: ( a ) ion exchangers, ( b ) electrolytes, ( c ) electrodes, and ( d ) chemical stores. Each has important applications with different fabrication requirements. Fast ion transport is required in electric-power applications, and various strategies are discussed for power batteries. The design of new materials begins with a theoretical model for ionic transport; the situation in stoichiometric compounds is compared with that in doped compounds, and electrolytes are contrasted with mixed ionic-electronic conductors. The most significant parameters for the synthetic chemist are the factors that govern the activation enthalpy ∆ H m for diffusion, the concentration c of mobile carriers, and the temperature T t for any phase transition from a normal to a fast ionic conductor. Strategies for decreasing ∆ H m and increasing c prove to be ion-specific, and the most successful strategies for each mobile ion are presented. The origin of a T t in stoichiometric com­pounds and the distinction between smooth and first-order transitions are also considered.


2014 ◽  
Vol 16 (41) ◽  
pp. 22513-22516 ◽  
Author(s):  
Ilan Riess

The interpretation of Onsager cross transport coefficients measured in mixed ionic electronic conductor (MIEC) oxides is examined.


Author(s):  
Tarini Prasad Mishra ◽  
Christian Lenser ◽  
Rishi Raj ◽  
Olivier Guillon ◽  
Martin Bram

2021 ◽  
pp. 160444
Author(s):  
S.U. Costilla-Aguilar ◽  
M.I. Pech-Canul ◽  
M.J. Escudero ◽  
R.F. Cienfuegos-Pelaes ◽  
J.A. Aguilar-Martínez

ChemInform ◽  
2012 ◽  
Vol 43 (28) ◽  
pp. no-no
Author(s):  
Arumugam Manthiram ◽  
Jung-Hyun Kim ◽  
Young Nam Kim ◽  
Ki-Tae Lee

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