A method for preparing zinc oxide nanostructures using arc discharge is disclosed. The method comprises the provision of an anode and a cathode in an arc discharge chamber. Current is supplied to the anode and the cathode to establish an arc discharge between the cathode and the anode to vaporise the anode and produce zinc oxide nanostructures. Contemplated is the use of the zinc oxide nanostructures to produce components that have applications in, for example, optoelectronics, energy storage devices, field emission devices, and sensors such as UV photosensors, gas sensors and humidity sensors. Disclosed is a gas sensor and method for its production, where said method comprises the provision of a sensor substrate comprising a conducting thin film at least partially covering at least two regions on at least one surface of a sensor substrate material to define a gap in the conducting thin film, the application of a mixture of zinc oxide nanostructures and a non-ionic polymer to at least a portion of the gap in the conducting thin film to thereby bridge the gap. Optionally contemplated is a step of annealing the mixture of zinc oxide nanostructures and non-ionic polymer applied to said sensor substrate to produce the sensor component.