Fig. 2From: Semiconductor Gas Sensors Based on Pd/SnO2 Nanomaterials for Methane Detection in AirTEM images of tin dioxide and sensor nanomaterials (with particles distribution). a Initial tin dioxide obtained by sol–gel technique. b Sensor material without Pd. c Sensor material containing 0.23 wt.% of Pd. d Sensor material containing 1.41 wt.% of PdBack to article page