Mechanical and electrochemical properties of carbon nanotubule-polyaniline nanowire/polyaniline nanoparticle high-strength ultra-flexible aerogel buckypaper

The carbon nanotube-polyaniline nanowire/polyaniline nanoparticle (CNT-PANI_nw/PANI_np) aerogel buckypaper (BP) was constructed, where PANI nanoparticles were uniformly embedded into the CNT network, and a series of downhanging PANI nanowires were grown in situ on the CNT monofilaments. The aerogel BP with 80 µm thickness had a PANI load of 3.5 mg/cm² and a porosity of 69%. The cross-junctions between CNT monofilaments were anchored by polyvinyl alcohol gel. It had a tensile strength of 25 MPa, with a strain of 11.4%, being folded along sharp creases or violently rubbed without damage. The specific capacitance of the aerogel BP electrode decreased from 3.070 to 2.064 F/cm², as the current density increased from 2 to 8 mA/cm², with a capacitance retention of 67.2%. Its specific capacitance was 1.720 and 1.560 F/cm² after 2000 folding in half–unfolding and 200 zigzag folding–unfolding cycles, respectively, with the capacitance retention of 84.0% and 76.2%, at 8 mA/cm². Its specific capacitance was 1.832 and 1.224 F/cm² after 2000 and 10,000 charge-discharge cycles, respectively, with the capacitance retention of 88.8% and 59.3%, at 8 mA/cm². Its residual specific capacitance after 10,000 cycles was higher than most of the reported initial value of the materials with similar compositions.