Single cobalt atoms with unconventional dynamic coordination mechanism for selective ammonia sensor.

Developing gas sensors that can simultaneously achieve high sensitivity and selectivity for the detection of a single-type gas remains a significant challenge. Herein we demonstrate cobalt (Co) single atoms with an unconventional dynamically changing coordination structure that could be used as NH-sensing material with superior sensitivity and selectivity. According to the steric effect of 2-methylimidazole (2MI) molecules and carbonyl groups on graphene, the Co single atom is evolved into a bidentate coordinated structure (Co-2MI-G).