MXene-Conducting Polymer@MXene Asymmetric Pseudocapacitors with Excellent Low Temperature Tolerance

A simple self-assembly method was used to synthesize two-dimensional PANI@MXene composites, in which MXene was used as a conductive network, which improved the conductivity of PANI and shortened the ion transport path in PANI. This makes PANI_0.5@MXene with the best quality ratio exhibit a high specific capacitance of 608 F g^-1 and good low temperature resistance（the capacity retention rate is more than 90% at-30 ℃ relative to room temperature）. Matching the PANI_0.5@MXene electrode with the excess porous MXene electrode can build an asymmetric pseudocapacitance supercapacitor with a wide voltage window of 1.3 V. With 40 wt% sulfuric acid as the electrolyte, the capacity can reach 32 mAh g^-1 at 20 ℃, the capacity can still maintain more than 80% of the capacity at room temperature at -60 ℃.