Fig. 1. (Color online) Schematic diagram of the preparation of CsPbBr₃ nanowires. (a) Preparation process of nanowires. (b) Cross-sectional schematic diagram of the device during preparation.

Fig. 2. (Color online) CsPbBr₃ nanowire photodetectors based on PbI₂ at different rotation speeds. (a) Statistics of photocurrent and dark current; (b) statistics of on/off ratio; (c) XRD.

Fig. 3. (Color online) CsPbBr₃ nanowire photodetectors with different immersion times in CsI growth. (a) Statistics of photocurrent and dark current; (b) statistics of on/off ratio; (c) XRD patterns.

Fig. 4. (Color online) SEM images of CsPbBr₃ nanowires with 1 h immersion growth time, (a) magnified 2000 times; (b) magnified 10 000 times; (c) cross-sectional view magnified 5000 times, SEM images of CsPbBr₃ nanowires with 4 h immersion growth time, (d) magnified 2000 times; (e) magnified 10 000 times; (f) cross-sectional view magnified 10 000 times.

Fig. 5. (Color online) CsPbBr₃ nanowire photodetectors with different immersion times in CsBr replacement. (a) Statistics of photocurrent and dark current; (b) statistics of on/off ratio; (c) XRD patterns.

Fig. 6. (Color online) Device performance of photodetectors with ITO/PbI₂/CsPbBr₃/carbon structure. (a) I−t curves under variable illumination intensity; (b) I−t curves under weak light; (c) LDR; (d) responsivity R and detectivity D*; (e) f_−3dB; (f) response time.

Fig. 7. (Color online) I−t curves of unencapsulated devices. (a) Heating on a heating stage at 86 °C for 6 h; (b) irradiated under a light intensity of 1.39 mW/cm² for 3600 s.