Enhanced toluene sensing performances of Pd- loaded SnO2 cubic nanocages with porous nanoparticle-assembled shells

Pure and Pd-loaded SnO2 cubic nanocages with hierarchically nanoparticle-assembled and porous shells have been successfully fabricated through a straightforward multi-step route. The synthetic step dependent structure evolution and the formation mechanism have been discussed. Furthermore, the toluene-sensing performances of these Pd-loaded SnO2 nanocages are elaborated and compared with those of pure SnO2. The toluene sensing results demonstrate that Pd-loaded SnO2 nanocages with the optimal loading amount of 1.0 mol% show a low detection limit (0.1 ppm) with response of 41.4-20 ppm toluene at the working temperature of 230 degrees C with the fast response time of 0.4 s, and improved selectivity. The improvement of toluene sensing properties is not only attributed to the effective utility of hollow and porous architecture, but also due to the dramatic sensitization of the loaded Pd nanoparticles. (C) 2016 Elsevier B.V. All rights reserved.