ИСТИНА

Electrochemical energy storage often plays a crucial role in overall performance of various devices. Electrochemical systems all deal with the electrode - electrolyte interfaces, where charge separation and chemical reactions occur. The evolution of the chemical composition and structure at the interfaces affects all the functional parameters of the device including power and long-term stability of its performance. That’s why chemical processes including side reactions at the interface should be thoroughly analysed. Although it is of a great importance, the analytical techniques are still very limited, and in most cases electrochemists act blinded as they have no ability to accomplish the electrochemical data with direct experimental characterisation of the interface, which is buried under electrolyte and thus is inaccessible to the most common surface science tools. The approaches to probe chemical reactions at electrified interfaces by X-ray photoelectron spectroscopy are discussed in the talk. Recent XPS observations of the electrochemical interfaces involving both solid and liquid electrolytes will serve as an examples for illustration of the new possibilities delivered by synchrotron radiation induced photoemission. Carbonaceous and some binary inorganic electrode materials for Li-air batteries were investigated and found to be intrinsically unstable due to its reactivity towards electrochemical reaction intermediates, namely superoxide species.