Alkali metal-incorporated spinel oxide nanofibers enable high performance detection of formaldehyde at ppb level.

Sensing material with high sensitivity, excellent selectivity and ultra-low detection limit is crucial for monitoring formaldehyde, which is a kind of hazardous gas to human health at very low concentration. Some one-dimensional semiconductor metal oxides show acceptable responses towards formaldehyde. However, the detection limit and selectivity of these sensors are still not satisfied, especially at ppb level.