Effect of Mn Concentration on Structural, Optical Properties and Humidity Sensing Activity of Tinoxide Nanoparticles

The nano structured pure and Mn doped SnO2 particles were synthesized and their structural, optical and humidity sensing properties were examined. The investigated samples were effectively prepared by hydrothermal method. The X- ray diffraction confirms the tetragonal rutile phase of the nano particles. The structural property of nano particles were analyzed by Transmission electron microscope (TEM) and the result shows the size of the nano particle around 50 nm in both pure and Mn-doped samples. The change in energy gap confirms the substitution of Mn into SnO2 sites by doping small amount of metal ion. Fourier transform infrared (FTIR) was used to determine functional group. The efficiency and the relationship between the resistance and relative humidity were verified by the humidity sensor analysis.