Overhead projector sheets as substrate for deposition of one-dimensional tin dioxide nanostructures for use as a chemoresistive sensor for hydrogen

One dimensional nanostructured branched wires of tin dioxide (SnO2) were prepared in an alumina boat by a self catalytic method at different temperatures in a flow of argon and oxygen. The SEM images exhibit the different morphologies of the nanowires with an i.d. of around 40 nm, and presence of core/cluster shell nanowires and of nano/microbelt structures. XRD studies show the product to possess a typical tin dioxide nanowire structure. FTIR and Raman studies revealed the bond information. The sensing properties were studied by monitoring the changes in conductivity on exposure to hydrogen gas. Hydrogen can be detected in the 1000 ppm to 3000 ppm concentration range, and the limit of detection for H2 is 1000 ppm.