NiO-Based Gas Sensors for Ethanol Detection: Recent Progress

Figure 4

XPS spectra for Ni-2p3/2 of (a) pristine NiO and (b) 3.2 at% Al-doped NiO. (c) Gas response of pure NiO and Al-NiO at various temperatures. (d) Gas response of pure NiO and Al-NiO at 228°C under the ethanol vary from 10 ppm to 500 ppm (reprinted/adapted by [89]).

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