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

Figure 4

(a) Graph of the change of resistance with humidity at different frequencies (CuO-based sensor). (b) Copper oxide-based humidity sensor resistance sensitivity change graph with humidity (18-22°C). (c) Resistive dynamic response to humidity under a CuO-based humidity sensor (18-22°C). (d) Comparative resistive dynamic response of CuO-based sensor towards humidity on day first and after 30 days [34].

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