Ionics

Recent material developments of fast solid oxide and lithium ion conductors are reviewed. Special emphasis is placed on the correlation between the composition, structure, and electrical transport properties of perovskite-type, perovskite-related, and other inorganic crystalline materials in terms of the required functional properties for practical applications, such as fuel or hydrolysis cells and batteries. The discussed materials include Sr- and Mg-doped LaGaO 3 , Ba 2 In 2 O 5 , Bi 4 V 2 O 11 , RE-doped CeO 2 , (Li,La,)TiO 3 , Li 3 La 3 La 3 Nb 2 O 12 (M=Nb, Ta), and Na super-ionic conductor-type phosphate. Critical problems with regard to the development of practically useful devices are discussed.

A robust and reliable gas sensing device is considered as a convenient and practical solution for gas concentration monitoring that has become a mandatory requirement in different field of applications. For in situ hazardous gases detection, a mixed-potential type gas sensor has been regarded as a promising solid-state gas sensor. For the past three decades, there has been a significant progress in achieving high performance in mixed-potential type sensors. Therefore, this review is focused on reporting the development of mixed-potential type gas sensors with combined yttria-stabilized zirconia (YSZ) as the base solid electrolyte material and various classes of electrode materials for their potential utilization as a high-performance sensing electrode. The underlying sensing mechanism of a mixed-potential type YSZ-based sensor is elaborated here in detail. Transformation in design and configuration of this type of sensor is also covered in this report. In addition, recent progresses on mixed-potential type gas sensors development for detection of several target gases, such as carbon monoxide, hydrocarbons, nitrogen oxides, hydrogen, and ammonia, are reviewed. Strategies to improve the sensing characteristic, particularly gas sensitivity and selectivity, are also reported. Based on the understanding of the fundamental sensing mechanism and the requirements for high-performance gas sensors, challenges and future trends for this type of gas sensor development are discussed.

This paper reviews the various classes of ionic liquids (ILs) in view of their established and expected applications in advanced electrochemical devices, such as lithium batteries, fuel cells, and supercapacitors. In this respect, particular attention is devoted to aprotic and protic ILs, with a related discussion in terms of their thermal and transport properties. In addition, the role in the electrochemical technology of a new class of ILs having cation and anion tethered in an intramolecular form is stressed. Due to their emerging importance, IL-based polymers are finally reported and discussed. A conclusion, where the expected evolution of the ILs research and development is evaluated, is also included.