Extremely Flexible Methanol Sensor Based on CNFs/ NiCo₂O₄ Nanocomposite

The development of a highly flexible, ultra-selective, and stable gas sensor is crucial in wearable electronic devices. Herein, carbon nanofibers (CNFs)/NiCo2O4 with different nanostructures were prepared and assembled as gas sensors for methanol detection. The CNFs/NiCo2O4 prepared by potassium permanganate treatment showed the highest gas sensitivity (0.1–100 ppm) and a good linear response. Meanwhile, the CNF/NiCo2O4 composite membrane sensors were tested after bending at different angles of 30°, 60°, and 90°. The response efficiencies could be maintained at 90.8%, 88.7%, and 87.1%, respectively, after 50 cycles, indicating that the sensors had good stability and flexibility. This approach provides a strategy for the controllable design and synthesis of homogeneous hierarchical CNF/transition metal oxide (TMO) composites for flexible gas sensor.