Mechanism Of Strain-dependent Carbon Nanotube Network Sensor

In recent years, significant progress in understanding the physics of carbon nanotube electronic devices and in identifying potential applications has occurred. It has been well documented that the electrical properties of a carbon naotube can be either metallic or semiconducting depending upon the tube's chirality. The carbon nanotube networks can be used as flexible sensor, but there is seldom research on its mechanism.Theoretical aspects of the unique electrical properties of carbon naotubes are reviewed. Then the effects on mechanical and electrical parameters have been calculated and evaluated. Based on percolation theory, a calculation formula for the electrical resistance change under strain has been deduced. It well explains the mechanism of carbon nanotube networks film strain sensor. After comparison and analysis with experimental data, it can be concluded that the change of carbon nanotubes volume fraction is the root cause to the electrical resistance change of the film during straining.