Table 10.

Summary of various processing routes for the production of 1-D nanostructures of non-convention sensors.

Materials	Synthesis Method	Starting Materials	Crystal Structure	Synthesis Temperature (°C)	Morphology	Diameter of TiO2 Nanostructure	Length of TiO2 nanostructure	Reference
WO2.72	Solvothermal	Tungsten hexachloride, ethanol	Monoclinic	200	Nanowire	5–30 nm	100–500 nm	[59,96]
WO3	Thermal oxidation	SiO2/Si substrate, porous single wall carbon nanotubes, arc-discharge chamber, DC sputtering, tungsten target, tube furnace	Monoclinic	700	Nanowire	70 nm	Few micrometer	[97]
β-AgVO3	Hydrothermal	V2O5 powder, Ag2O powder, distilled water	Monoclinic	180	Nanowires	50–100 nm (thickness)	100–700 nm (width)	[34,35]
CdO	Hydrothermal	CdCl2·2.5H2O, ethylenediamine, Na2CO3, NH3, distilled water, ethanol	Cubic	Nanowire: 180 Calcination: 300–650	Nanowire	120 nm	100μm	[99]
MoO3	Sol-gel	Molybdenum iso-propoxide	–	–	Nanoneedle	–	–	[39]
MoO3	Thermal evaporation	MoO3 powder, O2, Ar	Orthorhombic	770	Lamellar	500 nm (thickness)	5 μm (width)	[32]
CuO	Hydrothermal	Sodium dodecylbenzenesulfonate, CuSO4, NaOH, distilled water, absolute ethanol, H2PtCl6, HAuCl4, L-ascorbic acid, absolute ethanol, distilled water	–	120	Nanoribbons (loaded with Pt and Au)	2–8 nm (thickness)	30–100 nm (width)	[101]
TeO2	Thermal evaporation	Te metal, alumina crucible, silicon wafer	Tetragonal	400	Nanowire	30–200 nm	Tens of micrometers	[102]
α-Fe2O3	Hydrothermal	FeSO4.7H2O, CH3COONa.4H2O, deionized water, absolute alcohol	Hexagonal	500	Porous urchin	30–40 nm	500 nm	[31]