Micro spherical anatase phase TiO2 thin films for room temperature operated formaldehyde gas sensor applications

•TiO2thin films are prepared by spray pyrolysis method at room temperature.•The morphology and surface roughness of TiO2 thin films obtained at optimized temperature well suits for some gas sensor applications.•Micro-sphered morphological TiO2 thin film has shown maximum surface roughness.•Fabricated sensor element shows increased response with increased gas concentration at room temperature conditions.