Role of acid mixtures etching on the surface chemistry and sodium ion storage in Ti 3 C 2 T x MXene.

Two-dimensional transition metal carbides and/or nitrides (MXenes) have shown promise in developing electrochemical storage of metal ions within conductive galleries due to redox reactions with transition metal atoms. Here, effect of surface chemistry on electrochemical storage of sodium ions within MXene interlayers is investigated by etching Ti(3)AlC(2)MAX using different etchants - HF, HF/HCl, and HF/H2SO4.