Ionic liquids (ILs) are molten salts with melting points lower than 100 °C. They usually consist of pair of organic cation and anion. ILs exhibit unique properties such as non-volatility, high thermal stability, and high ionic conductivity and find applications as electrolytes in lithium/sodium ion batteries and dye-sensitized solar cells. They are also used as media for synthesis of conducting polymers and intercalation electrode materials. Ionic liquids (ILs) are molten salts with melting points lower than 100 °C. They usually consist of pair of organic cation and anion. ILs exhibit unique properties such as non-volatility, high thermal stability, and high ionic conductivity and find applications as electrolytes in lithium/sodium ion batteries and dye-sensitized solar cells. They are also used as media for synthesis of conducting polymers and intercalation electrode materials.