NO 2 gas-sensing enhancement by selective laser surface treatment of SnO 2 nanorods

A new surface engineering technology has been introduced that can dramatically change the morphology and composition of existing SnO 2 nanorods (NRs) to SnO x nanobeads (NBs) + NRs with the addition of a 1 - 6s laser + convex lens pair (LCP) process. Unlike the existing flame chemical vapour deposition (FCVD) method, which has a two-dimensional effect on a sample, LCP can control a relatively local area with a radius of several microns, making it a more sophisticated and advanced process. Notably, the LCP process at each second was directly linked to the change in the composition of the surface of the SnO 2 NRs, and the response to NO 2 gas in the SnO 2 NBs + NRs with 1second LCP process was improved by approximately three times compared to that of bare SnO 2 NRs. Therefore, a new gas-sensing mechanism was proposed through comparing the types of oxygen defect on the SnO 2 NRs surface during a slight morphological transition and thermodynamic data of the composition before and after gas sensing.