A flexible fiber-shaped solar chargeable zinc–polyaniline battery with a fullerene-based electron transfer layer

Wearable electronic devices demand monolithic solar rechargeable batteries that directly convert photon energy into electricity. Solar rechargeable batteries consist of an active material with electron-hole separation and energy storage ability. In an aqueous zinc-ion battery, a staggered p-n junction comprising n-type fullerene plasma-induced carbon clusters (FPC) and p-type polyaniline (PANI) is employed for a photoelectrode active material. The FPC material acts as an electron transfer layer to block the recombination of photoexcited electrons and holes generated in PANI under illumination. We fabricated an FPC–PANI-based solar battery that exhibited photo-enhanced capabilities of 300% at a high C-rate, with a high capacity of 310 mAh g−1 and a capacity retention of 91.3% for 2000 cycles upon light irradiation. After illumination for 10 h, the synergy between the photocathode and photoanode in the fiber-shaped configuration resulted in a record-high photon energy conversion efficiency of 1.15%, with high-flexibility performances as a wearable device.