Ultra‐Sensitive, Deformable, and Transparent Triboelectric Tactile Sensor Based on Micro‐Pyramid Patterned Ionic Hydrogel for Interactive Human–Machine Interfaces

TLDR

Rapid advances in wearable electronics and mechano‑sensational human–machine interfaces impose great challenges in developing flexible, deformable tactile sensors that are highly efficient, ultra‑sensitive, environment‑tolerant, and self‑sustaining. The study reports a self‑powered tactile hydrogel sensor that detects subtle pressure changes by measuring variations in triboelectric output without an external power supply. The sensor employs micro‑pyramid‑patterned double‑network ionic organohydrogels to generate triboelectric signals. The self‑powered THS shows remarkable flexibility, ≈85 % transparency, extraordinary sensitivity (45.97 mV Pa⁻¹), fast response (~20 ms), low detection limit (50 Pa), 36 000‑cycle stability, broad temperature tolerance (−20 to 60 °C), anti‑freezing/dehydrating properties, and can power switching applications such as controlling appliances and robotic hands.

Abstract

Abstract Rapid advances in wearable electronics and mechno‐sensational human–machine interfaces impose great challenges in developing flexible and deformable tactile sensors with high efficiency, ultra‐sensitivity, environment‐tolerance, and self‐sustainability. Herein, a tactile hydrogel sensor (THS) based on micro‐pyramid‐patterned double‐network (DN) ionic organohydrogels to detect subtle pressure changes by measuring the variations of triboelectric output signal without an external power supply is reported. By the first time of pyramidal‐patterned hydrogel fabrication method and laminated polydimethylsiloxane (PDMS) encapsulation process, the self‐powered THS shows the advantages of remarkable flexibility, good transparency (≈85%), and excellent sensing performance, including extraordinary sensitivity (45.97 mV Pa −1 ), fast response (≈20 ms), very low limit of detection (50 Pa) as well as good stability (36 000 cycles). Moreover, with the LiBr immersion treatment method, the THS possesses excellent long‐term hyper anti‐freezing and anti‐dehydrating properties, broad environmental tolerance (−20 to 60 °C), and instantaneous peak power density of 20 µW cm −2 , providing reliable contact outputs with different materials and detecting very slight human motions. By integrating the signal acquisition/process circuit, the THS with excellent self‐power sensing ability is utilized as a switching button to control electric appliances and robotic hands by simulating human finger gestures, offering its great potentials for wearable and multi‐functional electronic applications.