NiO-Based Gas Sensors for Ethanol Detection: Recent Progress

Figure 9

(a) SEM of NiO/SnO₂. (b) Enlarged image of (a) where the white arrow points. (c) Gas response of NiO/SnO₂ under different temperatures. (d) Gas response of NiO/SnO₂ under different gases (reprinted/adapted by [115]).

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