Polyaniline/graphene nanocomposites towards high-performance supercapacitors: A review

Among frequently investigated advanced electrode materials for supercapacitors, polyaniline (PANI) is considered as an ideal electrode material due to its high theoretical capacitance, desirable chemical stability, easy synthesis and low cost. However, neat PANI electrodes are lack of long-term stability and high power density due to their low surface area, large volume changes during release/doping of ions and low conductivity. The composition of PANI with carbon materials especially conductive and high-surface-area graphene provides an effective approach to solve these problems. This review presents an overview of recent advances in the design, synthesis and applications of PANI/graphene nanocomposites as high-performance electrode materials for supercapacitors. The PANI/graphene nanocomposites can combine the advantages of both electrical double-layer capacitances of graphene and pseudocapacitances of PANI, which therefore exhibit long cycle life and large energy density. Various strategies for the synthesis of PANI/graphene nanocomposites are briefly introduced, and several main factors influencing electrochemical capacitive performances of PANI/graphene nanocomposites are presented and discussed. Finally, the future research directions for the PANI/graphene nanocomposites for supercapacitors are also summarized and discussed.