Data from: Strain Sensors with Adjustable Sensitivity by Tailoring the Microstructure of Graphene Aerogel/PDMS Nanocomposites

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Strain sensors with high elastic limit and high sensitivity are required to meet the rising demand for wearable electronics. Here, we present the fabrication of highly sensitive strain sensors based on nanocomposites consisting of graphene aerogel (GA) and polydimethylsiloxane (PDMS), with the primary focus being to tune the sensitivity of the sensors by tailoring the cellular microstructure through controlling the manufacturing processes. The resultant nanocomposite sensors exhibit a high sensitivity with a gauge factor of up to approximately 61.3. Of significant importance is that the sensitivity of the strain sensors can be readily altered by changing the concentration of the precursor (i.e., an aqueous dispersion of graphene oxide) and the freezing temperature used to process the GA. The results reveal that these two parameters control the cell size and cell-wall thickness of the resultant GA, which may be correlated to the observed variations in the sensitivities of the strain sensors. The higher is the concentration of graphene oxide, then the lower is the sensitivity of the resultant nanocomposite strain sensor. Upon increasing the freezing temperature from -196 to -20 °C, the sensitivity increases and reaches a maximum value of 61.3 at -50 °C and then decreases with a further increase in freezing temperature to -20 °C. Furthermore, the strain sensors offer excellent durability and stability, with their piezoresistivities remaining virtually unchanged even after 10000 cycles of high-strain loading-unloading. These novel findings pave the way to custom design strain sensors with a desirable piezoresistive behavior.

附件文件为关联文章提供补充数据集。为满足可穿戴电子设备日益增长的市场需求，亟需兼具高弹性极限与高灵敏度的应变传感器。本研究基于石墨烯气凝胶（graphene aerogel, GA）与聚二甲基硅氧烷（polydimethylsiloxane, PDMS）组成的纳米复合材料，制备了高灵敏度应变传感器，核心研究目标为通过调控制备工艺优化其细胞状微观结构，以此调节传感器的灵敏度。所得纳米复合传感器展现出优异的灵敏度，其灵敏系数最高可达约61.3。尤为关键的是，通过改变前驱体（即氧化石墨烯水分散液）的浓度与制备石墨烯气凝胶所用的冷冻温度，可便捷地调节应变传感器的灵敏度。研究结果表明，这两项参数可调控所得石墨烯气凝胶的孔径与孔壁厚度，这与观测到的应变传感器灵敏度变化存在直接关联。氧化石墨烯浓度越高，所得纳米复合应变传感器的灵敏度越低。当冷冻温度从-196℃升高至-20℃时，传感器灵敏度随之提升，在-50℃时达到61.3的峰值，随后随着冷冻温度进一步升高至-20℃，灵敏度开始下降。此外，该应变传感器具备优异的耐久性与稳定性，即便经历10000次高应变加载-卸载循环，其压阻特性仍基本保持不变。这些创新性研究结果为定制化设计具备目标压阻特性的应变传感器提供了可行路径。