Formaldehyde detection of PEI-GO gas sensor at room temperature

초록

Graphene has been considered as a promising candidate for vapor sensor since its high surface area, conductivity and sensitivity to its surroundings which are attributed to its unique 2D structure, functionalities on the graphene surface, conjugated carbon system and porosity. However, graphene should be functionalized by heteroatoms to assign selectivity and higher response compared to bare graphene. Among various heteroatoms, nitrogen and functional groups consisting of nitrogen atoms seem to be able to interact with toxic gases due to its strong electronegativity and possible hydrogen bond with the molecules of toxic gases. Thus, we introduce polyethyleneimine which contains abundant amount of nitrogen atoms via one step reaction. As prepared sample is named as PEI-GO. The sample was characterized by XPS, SEM. The sensing performance of the sample toward toxic gases was measured by our customized gas sensor system. It responded to formaldehyde gas most strongly among ammonia, trimethylamine, formaldehyde gas.