SnO₂-microtube-assembled cloth for fully flexible self-powered photodetector nanosystems

Integrating an energy conversion or storage device with photodetectors into a self-powered system provides a promising route to future devices aimed at reduced size, low weight and high flexibility. We reported here the fabrication of a fully flexible self-powered photodetector nanosystem by integrating a flexible SnO₂-cloth-based ultraviolet photodetector with a flexible SnO₂-cloth-based lithium-ion battery. The flexible SnO ₂-cloth-based ultraviolet photodetectors showed fast response to ultraviolet light with excellent flexibility and stability. Using SnO ₂-on-carbon-cloth as the binder-free anode and commercial LiCoO ₂/Al foil as the cathode, a flexible full lithium-ion battery was assembled, exhibiting a reversible capacity of 550 mA h g^-1 even after 60 cycles at a current density of 200 mA g^-1 in a potential window of 2-3.8 V. When integrated with and driven by the flexible full battery, the fully flexible self-powered photodetector nanosystem exhibits comparable performance with an analogous externally powered device. Such an integrated nanosystem could serve as a wireless detecting system in large areas, as required in applications such as environmental sensing and biosensing.