Activating an MXene as a host for EMIm+by electrochemistry-driven Fe-ion pre-intercalation

EMIm(+), as a substitute for Li+, can solve the initial problems that accompany lithiation/delithiation processes on an anode. However, the larger size of EMIm(+)limits the options when it comes to electrode materials. Herein, a multilayered Ti(3)C(2)T(x)MXene was electrochemically pre-intercalated with Fe ions to achieve EMIm(+)hosting abilities. As a result, a pre-intercalated MXene electrode exhibited enhanced EMIm(+)transport and storage capabilities. When integrated with an EMIm(+)[PF6](-)ionic liquid electrolyte, the assembled DIB provides an energy density of 76 W h kg(-1)at a power density of 360 W kg(-1), and 94.3% of the energy density is retained after 50 cycles. Compared with a pristine example, the Fe pre-intercalated Ti(3)C(2)T(x)MXene showed a significant increase in electrochemical performance. Employing this approach to optimize layered materials may open up a new route for accurately tuning intercalated materials.