Post-deposition annealing influences of gas adsorption on semi-vertical β-FeOOH nanorods at room temperature: A scanning kelvin probe analysis

•An investigation on gas adsorption of β-FeOOH at room temperature was performed through kelvin probe analysis.•The energy band gap decreased with increasing annealing temperature.•The CPD changes for ethanol were higher (−264 mV) at lower temperatures (350 °C) and vice versa.•These adsorption studies provides notion on the fundamental mechanism of gas interaction.