# Understanding the Roles of Microstructure and Viscoelasticity of Soft Ionic Elastomer for Super‐Capacitive Pressure Sensors

## TL;DR

This paper explores how the microstructure and viscoelasticity of a soft ionic elastomer affect the performance of super-capacitive pressure sensors, leading to highly sensitive and durable devices for applications like wearable electronics and robotics.

## Contribution

The study establishes a detailed understanding of how microstructure and viscoelasticity influence sensor performance, enabling design guidelines for high-performance super-capacitive sensors.

## Key findings

- Height-graded architectures in the elastomer improve sensitivity, linear range, and durability of the sensor.
- The sensor achieves a sensitivity of 2.70 nF/kPa and a linear range up to 2000 kPa.
- The sensor is suitable for applications such as robotic e-skin and physiological monitoring.

## Abstract

Soft ionic conductive elastomers offer unique advantages for super‐capacitive pressure sensors, where the electrical double layer (EDL) effect enables high sensitivity and rapid response. However, the roles of microstructure and viscoelasticity on EDL‐driven sensing remain poorly understood. This study establishes detailed correlations between elastomer microstructure, intrinsic viscoelastic properties, and sensor performance by integrating mechanical and electrical analyses. Validation of the EDL mechanism reveals how microstructural optimization and viscoelastic tuning enhance sensitivity, linear range, and stability. Height‐graded architectures yield a sensor with a sensitivity of 2.70 nF/kPa, a broad linear range of 0–2000 kPa, and robust durability over 10 000 cycles. These devices demonstrate multifunctionality in robotic electronic skin, pressure mapping, and real‐time physiological monitoring such as wrist pulse detection. The findings establish key structure–property–performance relationships, providing design guidelines for next‐generation, high‐performance super‐capacitive sensors.

By engineering the PVA/H3PO4 ionic elastomer with optimized viscoelasticity and a height‐graded microstructure, the pressure sensor achieves a broad linear range up to 2000 kPa and a high sensitivity of 2.70 nF/kPa. These advancements underscore its strong potential for wearable electronics, including bio‐signal detection, health monitoring, and biomimetic e‐skin for soft robotics.