A percolation model of semiconductor gas sensors with a hierarchical pore structure

Abstract

A percolation model of gas sensors is proposed, on the basis of which the effect of material porosity, pore size and pore size distribution on the gas detection threshold is analyzed. It is shown that micropores exert the greatest influence on gas sensitive properties. An increase in the percolation threshold leads to an increase in the detection threshold of reducing gases. The developed percolation model is used to explain high sensitivity values of sensor structures obtained by the chemical co-precipitation method.

Keywords

• gas sensor
• percolation
• sol-gel method
• fractals
• hierarchical structures