“…RTILs remain in molten state at ambient temperature, therefore they are also known as room temperature molten salts [44, 155,156]. Ionic liquids can be divided as aprotic ionic liquids and protic ionic liquids with the latter being actively applied in polymer electrolytes for fuel cells [157][158][159][160][161]. Some inherent features of RTILs include non-volatility, nonflammablity, recyclablity, low melting point, low viscosity, low toxicity, negligible vapour pressure, high ionic conductivity, wide electrochemical window and excellent electrochemical, mechanical, chemical and thermal stabilities [35,44,46,[162][163][164][165][166][167][168][169][170][171].…”