The preparation of smart sensors with multiple sensory systems, reusable property, and high sensitivity remains a challenge. Here, inspired by a sponge, we develop a multisensory PCA–poly(vinyl alcohol) (PVA)/borax–LiCl hydrogel (named PPL hydrogel) with low cost and simple fabrication process using sodium polyacrylate (PAAS), PVA, and lithium chloride (LiCl) to address this challenge. PPL hydrogel has a sponge-like porous structure and can repeatedly “absorb” and “drain” water, while maintaining good tensile (strain up to 1442%) and electrical conductivity. PAAS builds the main skeleton of PPL hydrogels and provides the basis for building the pore structure, PVA enhances the mechanical properties of the crosslinked network, while LiCl ionic solution further improves the conductivity, which can reach 8.8 s m⁻¹ and be increased nearly 42 times better than without LiCl. Therefore, this makes PPL hydrogel a very sensitive sensing system for wearable devices that can be used to detect signals from the human body. Additionally, PPL hydrogel is also capable of detecting temperature due to its temperature-sensitive properties. Moreover, PPL hydrogel can also roughly identify the basic properties of different solvents. Our simple, low-cost and multisensory PPL hydrogel offers promising opportunities for multisensory sensors, even functional/smart materials, flexible/wearable devices, and medical care.

中文翻译：

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海绵启发的多感官水凝胶

制备具有多传感系统、可重复使用和高灵敏度的智能传感器仍然是一个挑战。在这里，受海绵的启发，我们使用聚丙烯酸钠 (PAAS)、PVA 和氯化锂开发了一种成本低且制造工艺简单的多感官 PCA-聚（乙烯醇）(PVA)/硼砂-LiCl 水凝胶（命名为 PPL 水凝胶） (LiCl) 来应对这一挑战。PPL水凝胶具有海绵状的多孔结构，可以反复“吸收”和“排干”水分，同时保持良好的拉伸（应变高达1442%）和导电性。PAAS构建了PPL水凝胶的主骨架并为构建孔隙结构提供了基础，PVA增强了交联网络的力学性能，而LiCl离子溶液进一步提高了电导率，可达8.8 s m ^-1并且比没有 LiCl 时提高近 42 倍。因此，这使得 PPL 水凝胶成为一种非常灵敏的可穿戴设备传感系统，可用于检测来自人体的信号。此外，由于 PPL 水凝胶的温度敏感特性，它还能够检测温度。此外，PPL水凝胶还可以粗略识别不同溶剂的基本性质。我们的简单、低成本和多感官 PPL 水凝胶为多感官传感器、甚至功能/智能材料、柔性/可穿戴设备和医疗保健提供了有前途的机会。