Synthesis, vibrational and thermal properties of new functionalized 1- (2-hydroxyethyl) -3-methylimidazolium dihydrogenophosphate ionic liquid

•A new hydroxyl-functionalized ionic liquid based on 1-(hydroxyethyl)-3-methylimidazolium dihydrogenophosphate was synthesized.•The Infrared and Raman analysis of hydroxyl-functionalized1-(hydroxyethyl)-3-methylimidazolium dihydrogenophosphate are reported for the first time.•Complete vibrational assignments have been performed.•The thermal properties have been investigated by TGA, DTG and DSC analysis. Very recently, the hydroxyl-functionalized ionic liquids have gained immense interest and were developed for a number of interesting applications. In this work and for the first time new hydroxyl-functionalized namely; 1-(hydroxyethyl)-3-methylimidazolium dihydrogenophosphate ionic liquid [EtOHMIM+][H2PO4−] was synthesized in our laboratory. The synthesis is based on an alkylation reaction of 1-methylimidazole followed by anion exchange. The obtained IL is characterized by 1H-NMR, 13C-NMR spectroscopy. Their experimental vibrational spectroscopy have been investigated using Infrared and Raman spectroscopy, based on the infrared (IR) and Raman spectroscopies results, complete vibrational assignments have been performed. Besides, thermal properties of this hydroxyl-functionalized IL were investigated by using following techniques, (i) Thermogravimetric Analysis (TGA) and Derivative Thermogravimetry (DTG) in the temperature range from 20 to 600 C°, (ii) differential scanning calorimetry (DSC) from-100 °C to 200 °C. The thermogravimetry analysis was coupled with mass spectrometry in order to assess the influence of anion on the measured property. [Display omitted]