“…In the present work, we propose to study the modification of these properties in Rb 0.8 (NH 4 ) 0.2 HSO 4 single crystal, motivated by their advantageous properties on one hand and their non-trivial character on the other hand. This family of materials, which combine the properties of ferroelectricity and a superconducting protonic phase, have been subject to intensive research in recent years [8][9][10][11] due to their important applications. In fact, these materials can be used in various electrochemical devices such as batteries, fuel cells, electrochemical sensors and electrochemical reactors [8,9].…”