The present invention relates to a process for preparation of a fluoride-free, surface functionalized MXene, the process comprising etching MAX phase with sulfuric  acid to obtain a partially oxidized MAX phase, treating the partially oxidized MAX phase with hydrogen iodide (HI) to obtain a charge transfer complex, etching the  charge transfer complex with vinegar to obtain the fluoride-free, surface functionalized MXene and optionally treating the fluoride-free, surface-functionalized MXene  with oxygen to obtain an oxygenated MXene. The process invention also relates to a fluoride-free, surface functionalized MXene as electrode and a process for  preparation of the same. The present invention further relates to a full cell for electrochemical device comprising the fluoride-free, surface functionalized MXene  electrode.