Thiol-ene UV-curable sponge electrolyte for low-voltage color changing wearable tactile device

Interest in developing advanced flexible materials that are stable, mechanically deformable, lightweight, cost-effective, and eco-friendly is ever-growing to support high-performance state-of-the-art wearable electronic devices. Another critical requirement of wearable devices is low energy consumption during operation for prolonged use. Herein, we demonstrate a compressible electrochromic device (ECD) using the three-dimensional (3D) compressible sponge electrolyte layer. A 3D porous sponge was fabricated using a facile and eco-friendly method of leaching sugar, a pore-creating agent, from an UV-cured skeletal structure. The simple structure of a compressible ECD is advantageous for its applicability as an optical tactile sensor device. A low-voltage operation, as evidenced by optical measurements, can ensure the long-term performance of the sensor. Furthermore, the color change in the ECD that occurs with the applied pressure acts as an effective pressure-sensing mechanism for the system involved. Thus, compressible sponge electrolytes layers are promising for various wearable tactile device applications. [Display omitted] •A compressible sponge electrolyte was fabricated by leaching sugar from the UV-cured thiol-ene polymer matrix.•The sponge was compatible with the ECD showing low-voltage operation performance than the film-type electrolyte.•The feasibility of the sponge-based ECD for applying a color-changing tactile sensor is demonstrated.