Fig. 4: Modulation of the electron double layer (EDL) effect for enhanced pressure sensing performance.

a Dependence of the areal capacitance on the measurement frequency for the dielectric layer with different IL concentrations (20, 30, and 50 wt%). b Changes in the capacitance with increasing pressure up to 8 kPa at measurement frequencies of 1 kHz, 10 kHz, 100 kHz, and 1 MHz (IL of 20 wt%). c Simulation of the electric field in the GPML with varying IL concentrations and the d highly nonlinear electric field across the space between the top and microstructured bottom electrodes (in the region marked by the red dashed box in c). Responses of the sensors based on e GPML500 and f GPML700 with various weight percentages of ILs.