A conceptually new and general strategy was, for the first time, proposed to significantly boost the electrocatalytic activity of metal-free pure carbon nanotubes (CNTs) towards the oxygen evolution reaction (OER) by simple polymer wrapping without introducing any heteroatom dopants, functional groups, or edge defects into the graphitic structure. Our strategy is straightforward, efficient, green, and easy to be scaled up. After wrapping pure CNTs with a certain class of electrochemically inert polymers (i.e. poly(ethylene-alt-maleic acid), poly(vinyl alcohol), poly(vinyl acetate), poly(ethylene glycol)) with polar oxygen-containing groups (i.e. –COOH, –OH, –COOCH3, –O–) through noncovalent interactions, a series of advanced metal-free composite membrane catalysts were easily achieved, which yielded unexpected, surprisingly high OER activity – on par with the commercial noble RuO2 catalyst, though pure CNTs have rather poor OER activity. Combined experimental and computational studies revealed that the observed superb OER activity could be attributed to a synergistic effect of intrinsic topological defects in the CNTs as active centers and the coated polymer layer as a co-catalyst to optimize the adsorption energies of intermediates for improving the OER energetics.

Molecular chain bonding is, for the first time, developed to synthesize a nanoporous, flexible and conductive polymer composite by converting a single polymer phase matrix to two phases of interpenetrating polymer networks. Significantly, the porous polymer composite not only presents ultra-high mechanical properties, durability and conductive stability, but also enhances the capacitance by 7-fold.

In this work, an ultra-high stability polyaniline that retained 100% of its initial capacitance after 45000 cycles was developed by designing and fabricating a ternary composite carbon nanotube/ethylvinylacetate/polyaniline (PANI/CNT/EVA) with a 3D co-continuous phase structure. The areal specific capacity of the PANI/CNT/EVA composite increased with increasing thickness. These findings hold great promise for the development of shape-conformable energy-storage devices.

A flexible and solid-state supercapacitor device based on TiO2@C core–shell nanowires has been developed and exhibited excellent flexibility—it can even be folded and twisted without sacrificing electrochemical properties—and good electrochemical performance with a maximum energy density of 0.011 mW h cm−3.

A flexible and solid-state supercapacitor device based on TiO2@C core–shell nanowires has been developed and exhibited excellent flexibility—it can even be folded and twisted without sacrificing electrochemical properties—and good electrochemical performance with a maximum energy density of 0.011 mW h cm−3.

In this work, an ultra-high stability polyaniline that retained 100% of its initial capacitance after 45000 cycles was developed by designing and fabricating a ternary composite carbon nanotube/ethylvinylacetate/polyaniline (PANI/CNT/EVA) with a 3D co-continuous phase structure. The areal specific capacity of the PANI/CNT/EVA composite increased with increasing thickness. These findings hold great promise for the development of shape-conformable energy-storage devices.

Molecular chain bonding is, for the first time, developed to synthesize a nanoporous, flexible and conductive polymer composite by converting a single polymer phase matrix to two phases of interpenetrating polymer networks. Significantly, the porous polymer composite not only presents ultra-high mechanical properties, durability and conductive stability, but also enhances the capacitance by 7-fold.