Customizable Metal Micromesh Electrode Enabling Flexible Transparent Zn-Ion Hybrid Supercapacitors with High Energy Density.

Abstract

Emerging flexible and wearable electronic products are placing a compelling demand on lightweight transparent energy storage devices. Owing to their distinguishing features of safety, high specific energy, cycling stability, and rapid charge/discharge advantages, Zn-ion hybrid supercapacitors are a current topic of discussion. However, the trade-off for optical transmittance and energy density remains a great challenge. Here, a high-performance Zn-ion hybrid supercapacitor based on the customizable ultrathin (5µm), ultralight (0.45mg cm-2), and ultra-transparent (87.6%) Ni micromesh based cathode and Zn micromesh anode with the highest figure of merit (84843) is proposed. The developed flexible transparent Zn-ion hybrid supercapacitors reveal excellent cycle stability (no decline after 20000 cycles), high areal energy density (31.69 µWh cm-2), and high power density (512 µW cm-2). In addition, the assembled solid flexible and transparent Zn-ion hybrid supercapacitor with polyacrylamide gel electrolyte shows extraordinary mechanical properties even under extreme bending and twisting operation. Furthermore, the full device displays a high optical transmittance over 55.04% and can be conformally integrated with diverse devices as a flexible transparent power supply. The fabrication technology offers seamless compatibility with industrial manufacturing, making it an ideal model for the advancement of portable and wearable devices.