Abstract:
A surfactant free template assisted electrodeposition method was
used to fabricate thick n-type Cu2O films having cubic
nanostructures for the detection of liquefied petroleum (LP)
gas at low concentrations. Templates were fabricated by initially
electrodepositing a p-type Cu2O thin film on a Ti substrate
followed by annealingthat changed conductivitytype ofthefilm,
as confirmed by Mott–Schottky and spectral response measure ments. SEM measurements of resultingfilms showed nano-cubic
crystals having sizes of 150–300 nm.When exposed to a mixture
of LP gas and dry air, the resistance of these films increased and
the maximum response was recorded when films were
maintained at 180 8C for all concentrations and it was
independent of the surface morphology. At 180 8C, at the lowest
tested LP gas concentration of 2 vol.%, a twofold increase in
response was observed in the nano-cubic films compared to the
micro-crystalline n-type Cu2O films. This improvement in gas
response is attributed to increased effective surface area of these
nanostructured films. Compared to other LP gas sensing
materials, Cu2O films showed very good response times and
recovery times of 120 and 90 s, respectively
