Abstract
Direct conversion of single-layer SnO nanoplates to multi-layer SnO 2 nanoplates is achieved by annealing in an O 2 ambient at 700°C. For 50 ppm ethanol, the sensitivities of the multi-layer SnO 2 nanoplates are more than double that of single-layer SnO 2 nanoplates, which are also formed from the single-layer SnO. The higher sensitivity of the multi-layer nanoplates is attributed to their larger surface/volume ratio. The facile fabrication of interconnected multi-layer SnO 2 nanoplates at low temperature directly on a Si substrate and sensing chip without the aid of catalysts offers vast advantages over competing methods for the fabrication of high-sensitivity SnO 2 sensors. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA.