Both bending stability and high sensitivity are two important problems to be solved in developing flexible sensors. The flexible sensor based on flower-like polyaniline coated filter paper (PCFP) was developed by spraying for the first time, achieving the non-contact and fast detection of nitroaromatic explosives. Hierarchical structure, high permeability of filter paper and the interaction between amino groups of PANI and nitro groups of nitroaromatic explosives contributed to the sensitive and fast response to 2, 4, 6-trinitrotoluene (TNT), picric acid (PA) and 2, 4-dinitrotoluene (DNT) at room temperature. The responses of PCFP to TNT, PA and DNT run up to about 237.7, 100.6 and 80.1%, respectively. The average response time and recovery time to TNT, PA and DNT are no more than 8.1 and 1.9 s, respectively. The theoretical limit of detection for TNT and PA is 0.094 and 0.029 ppb, respectively. More importantly, the special interlaced flower-like structures of polyaniline contributed to the good flexural stability. The response fluctuation to TNT, PA and DNT do not exceed 7% in the bending process and the decreases of responses are less than 7.9% after 2,000 bends of 40°. In addition, the spraying method is suitable for economical, efficient and large-scale preparation of paper-based flexible sensors.

弯曲稳定性和高灵敏度都是开发柔性传感器要解决的两个重要问题。首次通过喷涂开发了基于花状聚苯胺涂层滤纸（PCFP）的柔性传感器，实现了非接触性和快速检测硝基芳族炸药。层状结构，滤纸的高渗透性以及PANI的氨基与硝基芳族炸药的硝基之间的相互作用有助于敏感，快速地响应2,4,6-三硝基甲苯（TNT），苦味酸（PA）和2,4 -二硝基甲苯（DNT）在室温下。PCFP对TNT，PA和DNT的响应分别高达约237.7％，100.6和80.1％。对TNT，PA和DNT的平均响应时间和恢复时间分别不超过8.1和1.9 s。TNT和PA的理论检出限分别为0.094和0.029 ppb。更重要的是，聚苯胺的特殊交错花状结构有助于良好的挠曲稳定性。在弯曲过程中，对TNT，PA和DNT的响应波动不超过7％，并且在40°弯曲2,000次后响应下降小于7.9％。另外，该喷涂方法适合于经济，有效和大规模制备纸基柔性传感器。