Fig. 1. SEM images of ZnO nanostructures with different morphologies^［17］

Fig. 2. Nanorods prepared by hydrothermal method^［19］

Fig. 3. SEM images of ZnO samples with different doping concentrations^［23］

Fig. 4. HRSEM images of ZnO@CNFs at different magnifications^［34］

Fig. 5. SEM micrographs of ZnO powders at different pH values^［38］

Fig. 6. SEM micrographs of ZnO films annealed at different temperatures under O₂ atmosphere^［47］

Fig. 7. BN-ZnO and GOx/BN-ZnO SEM diagrams and XRD diagrams^［53］

Fig. 8. Schematic of the working principle of the biosensor

Fig. 9. Schematic diagram of electrochemical sensing mechanism of SH-labeled probe DNA^［58］

Fig. 10. 3D fiber optic FO-LSPR sensor system ^［70］

Fig. 11. Process and physical SEM photos of nanoPAA-ZnCl₂/CuCl₂-Au^［77］

Fig. 12. FET biosensor structure^［86］

Fig. 13. IGZO-FET Field Effect Transistor Glucose Biosensor^［87］

Fig. 14. Characterization of biosensor device and its nanowires^［15］

Fig. 15. Separated extended gate AlGaAs/GaAs HEMT biosensor ^［91］

Fig. 16. Self-powered creatinine biosensor^［94］

Fig. 17. Schematic diagram of self-powered wearable biosensors in baby diapers^［95］