Perovskite oxides like SrTiO₃ at the nanoscale are of interest for emerging applications, including high-k dielectrics and sensors. However, their synthesis requires long calcination at the elevated temperature, which is a barrier of their application to flexible electronics. Here, an effective laser-assisted sol-gel method to patternably produce SrTiO₃ nanoparticles (∼ 100 nm) in selective areas on polyimide substrates (coated with ITO) is introduced. Importantly, the violet-laser power is just 1 W but sufficient to crystallize the material in a short period (a few seconds). Furthermore, developing a flexible device platform using carbon nanotubes (CNT) and SrTiO₃ nanoparticles for detection of humidity changes at room temperature is proposed. The sensor platform has both capacitive and resistive sensing abilities. The resistive mode with a lower power usage (about 0.2 μW) is suitable for long monitoring of humidity in the range of 2% RH and above. The capacitive mode with higher sensitivity, faster response/recovery time (1∼3 min), and lower detection limit (0.5% RH) can be used for calibration purposes. The performance of the flexible sensor is still maintained after 5000 bending cycles at 1.5-cm radius. Altogether, our synthesis method and the flexible sensor show chances for mass-producing perovskite oxides at low cost for wearable electronics.

纳米级的钙钛矿氧化物（如SrTiO _3）对于包括高k电介质和传感器在内的新兴应用很感兴趣。然而，它们的合成需要在高温下长时间煅烧，这阻碍了它们在柔性电子学中的应用。在此，介绍了一种有效的激光辅助溶胶-凝胶法，该方法可在聚酰亚胺基材（涂有ITO的基材）上的选择性区域中图案化地生产SrTiO ₃纳米颗粒（〜100 nm）。重要的是，紫激光功率仅为1 W，但足以在短时间内（几秒钟）使材料结晶。此外，开发使用碳纳米管（CNT）和SrTiO ₃的柔性设备平台提出了用于检测室温湿度变化的纳米粒子。传感器平台具有电容和电阻感测能力。具有较低功耗（约0.2μW）的电阻模式适用于对湿度在2％RH以上的湿度进行长时间监控。具有较高灵敏度，更快的响应/恢复时间（1-3分钟）和较低的检测极限（0.5％RH）的电容模式可用于校准。在1.5 cm半径下进行5000次弯曲之后，柔性传感器的性能仍保持不变。总之，我们的合成方法和柔性传感器为可穿戴电子产品提供了以低成本大量生产钙钛矿氧化物的机会。