Research Progress on Humidity-Sensing Properties of Cu-Based Humidity Sensors: A Review

Figure 17

(a) Scanning electron micrograph of sample CZ-1 (1.0% by weight of CuO in ZnO). (b) Variation in resistance with change in %RH for sample CZ-1: (A) increasing cycle and (B) decreasing cycle. (c) Variation in resistance with change in %RH for sample CZ-1 for annealing temperature 400°C: (A) increasing cycle and (B) repeated cycle after 3 months. (d) Variation in sensitivity with wt% of CuO in ZnO [83].

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(b)

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(d)