Selected functionalization of continuous graphene fibers for integrated energy conversion and storage

Increasing attention has been paid to develop flexible integrated energy devices, but it remains a big challenge to achieve a common electrode for building both energy conversion and storage devices with high performance. Here, we for the first time selectively functionalize polyaniline (PANI) and platinum (Pt) inside different segments of chemical vapor deposition grown continuous graphene tube, achieving selectively functionalized graphene composite (PANI//Pt@G) fibers. The PANI@G and Pt@G parts could be used as efficient electrodes for supercapacitor with a specific capacitance of 284 mF cm^-2 and dye-sensitized solar cell with a power conversion efficiency of 4.73%, respectively. By using a PANI//Pt@G fiber as the common electrode, an integrated energy device with a total energy conversion and storage efficiency of 3.07% is realized. The continuous graphene tubes could be functionalized with other active materials for other flexible and wearable electronics.