Design and electrosynthesis of monolayered MoS2 and BF4−-doped poly(3,4-ethylenedioxythiophene) nanocomposites for enhanced supercapacitive performance

Abstract

Currently, the nanocomposites based on MoS2 and conducting polymer (CPs) are mainly prepared by the chemical oxidation polymerization of monomers with the presence of MoS2 nanosheets. The disadvantage is that the aggregation and re-stacking of monolayered MoS2 occur easily. In the electrosynthesis of CPs, monolayered MoS2 with negative charges can be uniformly doped into CPs film, thus avoiding the above disadvantage. Herein, a direct electrochemical deposition method is used to incorporate the exfoliated monolayered MoS2 into BF4−-doped poly(3,4-ethylenedioxythiophene) (PEDOT(BF4−)) film, forming PEDOT(BF4−)/MoS2 nanocomposite. The as-prepared monolayered MoS2, PEDOT(BF4−) and PEDOT(BF4−)/MoS2 nanocomposite are characterized by AFM, SEM, TEM, EDX and electrochemical means. The results indicate that PEDOT(BF4−)/MoS2 nanocomposite has specific capacitance of 149.8mFcm−2 at 1.0mAcm−2, which is 4.3 times higher than PEDOT(BF4−) (35mFcm−2). And the specific capacitance of PEDOT(BF4−)/MoS2 nanocomposite remains about 85% of the initial capacitance after 1000cycles at 8mAcm−2. Therefore, the monolayered MoS2 doped into PEDOT(BF4−) film can further improve the capacitance performance of PEDOT(BF4−), which is attributed to the porous nano-network structure of composite and the synergistic effect between MoS2 and PEDOT in the composite.