Mirela Dragan

By Mirela Dragan, Stanica Enache, Mihai Varlam and Konstantin Petrov

Lanthanum cobaltite (LaCoO3) perovskite-type oxide is an important conductive ceramic material finding a broad range of technical applications. Physical and chemical properties of the final lanthanum cobalt oxide powder material obtained are strongly dependent on the method of preparation. Taking in account these considerations, we focus our investigation on the solid state reaction process. The characterization of prepared lanthanum cobalt oxide material was studied by using X-ray diffractometry (XRD), scanning electron microscopy (SEM), thermogravimetry-differential scanning calorimetry (TG-DSC), and conduction properties. Following the experimental results, it can be concluded that with proper improvement, the solid state reaction process may also provide an efficient preparation method for perovskite-type LaCoO3 powder. Important to mention is that we looked into the aspects to produce again same which showed consistently reproducibility of batch to batch powder properties. This is a key factor to overcome a successful commercialization of new material synthesis development.

Part of the book: Cobalt Compounds and Applications

By Mirela Dragan, Stanica Enache, Mihai Varlam and Konstantin Petrov

The role of energy in modern society is fundamental. Constraints due to the emissions of air pollutants from the excessive use of fossil fuels have increased dramatically in the last years. Over the years various devices and systems have been developed to transform energy from forms supplied by nature to forms that can be used by people. Another issue is to absorb energy generated at one time and to discharge it to supply power at a later time, what is called energy storage. This is also a matter to focus when it comes to searching for solutions of energy problems. Perovskites are promising key materials for energy applications, and in this chapter is a literature review summarizing the reported progress in energy applications of perovskite-type ceramic materials. To understand the fundamental nature of structure–property relationships, defect chemistry plays an important role. This paper, a mini-review, briefly describes from available literature and summarizes accordingly. It is focused on perovskite crystal structures, perovskite materials for solid oxide fuel cells, perovskite electrocatalyst and photocatalysts, and perovskite transport features.

Part of the book: Perovskite Materials, Devices and Integration

By Irina Petreanu, Mirela Dragan and Silviu Laurentiu Badea

This paper presents a classification and also an overview of fuel cells, including the working principles, the equations of the governing reactions, and the main applications. A brief exposure of thermodynamics and electrochemical theory describe the functioning of the fuel cells. Further, the proton exchange membrane fuel cells assembly, starting with the schematic presentation of the main components, the role of each component in fuel cell, the specific materials and their requested properties, and the way of assembling the components into device will be detailed. In conclusion, the challenges related to reliability and the cost and the targets for future development of the proton exchange membrane fuel cells for mobile and stationary applications will be presented.

Part of the book: Thermodynamics and Energy Engineering