1-Ethyl-3-methylimidazolium tetrafluoroborate (EMIM BF4) is an ionic liquid comprised of an ethyl-substituted methylimidazolium cation and a tetrafluoroborate anion. Its molecular formula is C8H14BF4N2. EMIM BF4 exhibits low volatility, high thermal stability, and excellent solvation properties, making it an attractive alternative to traditional organic solvents in various chemical processes. This ionic liquid has found applications in fields such as green chemistry, catalysis, electrochemistry, and materials science.