Flexible and capsular polypyrrole nanotubular film based pseudo-capacitive electrode with enhanced capacitive properties enabled by Au nanoparticles doping
Conducting polymers (CPs) based pseudocapacitive electrodes with good capacitance/rate capability and high potential window retention (namely, neglectable IR drop) under high current density are of great interest driven by their practical applications in fabricating instantaneous and high powering energy devices but still a challenge to be realized. Herein, we report an alternative route to enhance these capacitive properties of polypyrrole nanofibrous membrane (PPy NM) based electrodes without any capacitive materials but Au nanoparticles doping via electrospinning and followed by in-situ polymerization. Compared with pristine PPy NM, the specific capacitance of Au/PPy NM has been enhanced from 193.7 F g-1 to 455.3 F g-1 at the scan rate of 5 mV s-1. Additionally, the rate capability is also enhanced under broaden current density ranging from 0.5 A g-1 to 30 A g-1 and wide scan rate from 5 mV s-1 to 1000 mV s-1. Interestingly, potential window retention has been hugely enhanced from 74.5% (PPy NM) to 95.6% under wide current density (0.5 A g-1 to 30 A g-1). Furthermore, Au/PPy NM also exhibits good circling stability (> 85% for 10000 charge-discharge cycles under the current density of 30 A g-1).