LAUSR

Abstract Solution-processable V2O5 nanobelts are successfully synthesized by a very simple and large-scale solution treatment method using commercial bulk V2O5 powders as precursor. The prepared V2O5 nanobelts with lengths up to 20 μm, widths of 10–30 nm, and aspect ratio of over 1000 displays excellent electrochromic and electrochemical capacitance performance. A large optical modulation, rapid switching speed and remarkable cycling stability (sustaining 94% of its initial optical contrast after 1000 cycles) are achieved for V2O5 nanobelt film (V2O5-nb film). And the V2O5-nb film also shows large specific capacitance and excellent capacitance retention (capacitance decay of only 5% after 500 cycles). In addition, the level of stored energy for V2O5-nb film could be simultaneously monitored by a reversible and fast color change even at high current charge/discharge conditions (16 A/g). The spray-processable large-scale patterned electrochromic displays based on V2O5 nanobelts exhibited various color variation and large optical contrast. The solution-processable V2O5 nanobelt shows promising features for applications in energy efficient displays, lithium-ion batteries, supercapacitors and electrochromic devices.