Fig. 4. Stability of the EGaIn capacitors depending on the thickness of oxide layer. (a) CV curves of the oxide-free EGaIn capacitor during 200 cycles. (b) Comparison of CV curve of the oxide-free EGaIn capacitor at 200th cycle, to that of the EGaIn capacitor with the native oxide at the first cycle. (c) CV curve of the EGaIn capacitor with thicker oxide by 1 V
Fig. 5. Capacitance for 200 cycles at difference oxide thickness. The scan rate is 500 mV/s
Fig. 6. Effect of electrolyte concentrations on CV curves of EGaIn based capacitors; (a) 0.01 M, (b) 0.1 M, (c) 1 M. For the stable CV measurement, oxide skin was further oxidized under 1 V for 30 seconds. Aqueous Na2SO4 solutions were used as the electrolyte
Fig. 1. (a) Experimental setup of a EGaIn capacitor. (b) Electrochemical process for removal or formation of the oxide layer on EGaIn electrodes by bias application
Fig. 2. (a) A top-view image of the EGaIn liquid metal electrodes of the EGaIn capacitor. Scale bar=0.5 mm. (b) Chargingdischarging mechanism of the EGaIn capacitor. (c) CV curves of the EGaIn capacitor with native oxide at different sweep rates. 1 M of Na2SO4 aqueous solution was used as electrolyte
Fig. 3. (a) Top-view images of EGaIn liquid metal electrodes after further oxidation with different oxidative voltages. Scale bar=0.5 mm. Each oxidative voltage was applied for 30 s. (b)CV curves of the capacitors with the EGaIn electrodes in (a). The scan rate is 200 mV/s
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