A Dual-Responsive, Freezing-Tolerant Hydrogel Sensor and Related Thermal- and Strain-Sensitive Mechanisms
A Dual-Responsive, Freezing-Tolerant Hydrogel Sensor and Related Thermal- and Strain-Sensitive Mechanisms
复制标题
双响应、耐冷冻水凝胶传感器及相关的热和应变敏感机制
DOI：
10.1021/acsapm.0c01346
复制
发表时间：
2021-02-11
影响因子：
5
通讯作者：
Huang, Chuanzhen
中科院分区：
文献类型：
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作者：
Yan, Yonggan;Wei, Luxing;Huang, Chuanzhen
耐冻导电水凝胶作为一种有前途的柔性传感器材料在冻态条件下引起了人们极大的兴趣。在这项工作中，抗冻，双响应水凝胶传感器的开发，通过使用离子-甘油杂化水凝胶。所制造的水凝胶传感器被证明能够有效地检测-30至100摄氏度范围内的不同温度或检测两种小应变（例如，1%、2%、4%）和大菌株（例如，10%、20%和30%）作为耐冷冻应变传感器。系统地研究了该水凝胶的热敏性和应变敏感性机理。结果发现，随着温度（T）的降低，水凝胶的电阻迅速增加。此外，应变灵敏度随着T从0 ℃降低到-30 ℃而增加。令人惊讶的是，当凝胶的拉伸应变达到临界值（例如，2620%在0 ℃）或在将水凝胶从25 ℃移动到-10 ℃到-30 ℃时。发现电阻的这种急剧增加主要是由于大量内部水凝胶网络在大应变下突然断裂或在低温下凝胶网络中出现微晶引起的。这项工作提供了基本的和实际的见解，为工程应用制造功能性耐冷冻水凝胶传感器。
Freezing-tolerant and conductive hydrogels have attracted tremendous interest as promising materials for flexible sensors under the gelid condition. In this work, a freezing-tolerant, dual-responsive hydrogel sensor was developed by using an ionic-glycerol hybrid hydrogel. The fabricated hydrogel sensor was demonstrated to detect efficiently different temperatures ranging from -30 to 100 degrees C or to detect both small strains (e.g., 1%, 2%, 4%) and large strains (e.g., 10%, 20% and 30%) as a freezing-tolerant strain sensor. A systematic investigation was conducted to explore the thermal- and strain-sensitive mechanisms of the obtained hydrogel. It was found that the resistance of the hydrogel rapidly increased as the temperature (T) decreased. In addition, the strain sensitivity increased as T decreased from 0 degrees C to -30 degrees C. Surprisingly, an abrupt resistance increase was observed when the tensile strain of the gel reached a critical value (e.g., 2620% at 0 degrees C) or upon moving the hydrogel from 25 to - 10 to - 30 degrees C. Such a sharp increase in resistance was found to be mainly caused by the abrupt fracture of a vast amount of the inner hydrogel network at large strains or the appearance of microcrystals in the gel network at low temperatures. This work provides fundamental and practical insights into fabricating functional freezing-tolerant hydrogel sensors for engineering applications.