Graphene sheets decorated with SnO2 nanoparticles: in situ synthesis and highly efficient materials for cataluminescence gas sensors

Graphene sheets decorated with SnO2 nanoparticles were prepared through a facile hydrothermal-assisted in situ synthesis route. According to the XPS, XRD, FESEM and TEM analysis, rutile SnO2 nanocrystals were exclusively deposited on graphene sheets with high density and high uniformity to form layered composite sheets. Propanal, a common volatile organic compound, was selected as a model to investigate the cataluminescence (CTL) sensing properties of the SnO2/graphene composite in this paper. It was found that the strong CTL emission could be generated due to the catalyzing oxidization of propanal on the surface of SnO2/graphene composite and this composite was an efficient sensing material for propanal. We further studied the analytical characteristics of the CTL sensor based on SnO2/graphene composite sensing material for propanal under the optimal experimental conditions. The linear range of the propanal gas sensor was 1.34-266.67 mu g mL(-1) (r = 0.9987), over two orders of magnitude, and the detection limit was 0.3 mu g mL(-1)(S/N = 3).