A Study of All-solid-state Planar Micro-supercapacitors Using Printable MoS2 Inks

Wearable energy storage electronics with high safety and long life have been promising candidates in recent years. Herein, all-solid-state planar micro-supercapacitors (MSCs) were demonstrated by inkjet printing of molybdenum disulfide (MoS2) electrodes. The preprinted PEDOT: PSS film on PI (Polyimide) substrate prepared with a simple and low-cost desktop inkjet printer can greatly improve the electrode conductivity. Additionally, the obtained planar MSCs show good electrochemical performance with high areal capacitance of 323 µF cm−2 and areal energy density of 0.016 µWh cm−2. More importantly, the MSCs exhibit outstanding flexibility with almost no degradation under various bending angles. The capacitance retention can still be maintained at 88.5% even after 8000 cycles, indicating good cycle stability of MSCs. The in-plane flexible MSCs hold great application potential for wearable and integrated energy storage electronics.