Flexible piezoresistive sensors have attracted great attention for the real-time monitoring of sleep apnea syndrome (SAS) through respiratory airflow. Although two-dimensional ultrathin Ti₃C₂ is regarded as a promising piezoresistive material, its poor structural compressibility and antioxidation limit its practical applications. Here, an innovative atomic sulfur-bonded strategy is proposed to fabricate large-sized, crumpled, and antioxidative Ti₃C₂/Na₂S (TS) flakes for preparing flexible piezoresistive sensors. The fundamental mechanism is rooted in the synergistic effect of lateral boundary assembly of Ti₃C₂ nanosheets into large flakes (∼7 μm), lattice distortion to induce crumpled structures, and edge passivation by S²⁻ ions to mitigate oxidation (105 days). The crumpled microstructure provides abundant voids for enhanced compressibility and contact site variability, resulting in a 5-fold sensitivity improvement over the Ti₃C₂ sensor and an ultralow detection limit of 0.2 Pa. We demonstrate the practical application of highly sensitive and stable piezoresistive sensors integrated into a respiratory monitoring system for SAS detection.

中文翻译：

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用于柔性压阻式传感器监测睡眠呼吸暂停综合征的原子硫键碳化钛纳米片


柔性压阻式传感器因通过呼吸气流实时监测睡眠呼吸暂停综合征 （SAS） 而引起了极大的关注。尽管二维超薄 Ti ₃ C ₂ 被认为是一种很有前途的压阻材料，但其较差的结构压缩性和抗氧化性限制了其实际应用。在这里，提出了一种创新的原子硫键合策略来制造大尺寸、皱巴巴和抗氧化的 Ti ₃ C ₂ /Na ₂ S （TS） 薄片，用于制备柔性压阻式传感器。基本机制植根于 Ti ₃ C ₂ 纳米片横向边界组装成大片 （∼7 μm）、晶格畸变诱导皱缩结构以及 S ²⁻ 离子边缘钝化以减轻氧化（105 天）的协同效应。皱巴巴的微观结构提供了丰富的空隙，以增强可压缩性和接触位点可变性，从而使灵敏度比 Ti ₃ C ₂ 传感器提高了 5 倍，检测限为 0.2 Pa。我们展示了集成到呼吸监测系统中用于 SAS 检测的高灵敏度和稳定的压阻传感器的实际应用。