Facile fabrication of laser-scribed-graphene humidity sensors by a commercial DVD drive

Monitoring the environmental humidity are of great significance to human comfort and product quality in many fields. However, high performance humidity sensors are difficult to be widely used because of their cost and complex preparation process. It is also highly desirable to develop a facile fabrication method that is capable of producing humidity sensors of customized size, shape, and geometry. Here, using a low power DVD drive, we successfully fabricate a highly sensitivity and low-cost humidity sensor, consisting of laser-scribed graphene (LSG) electrode and graphite oxide (GO) sensing layer. The LSG-GO humidity sensor operates in the relative humidity (RH) range of 19 %-97.4 %, demonstrating high sensitivity (4770.14 pF/% RH), quick response/ recovery, and excellent sensing stability. In addition, the possible humidity sensing mechanism is discussed with the help of impedance spectroscopy. These results indicate that the LSG/GO sensor, enabled by the facile fabrication process with low power DVD drives, demonstrates promising potential with broad application prospects.