Why does zinc oxide exhibit enhanced electrical conducity on heating ?

Explanation

On heating , zinc oxide losses oxygen as : `ZnO oversetDeltaZn^(2+)+ 1/2 O_2 + 2e^(-)`
The `Zn^(2+)` ions thus formed are entrapped into the interstitial sites while the electrons are also entrapped in the neighbouring interstitial sites . These entrapped electrons enhance the electrical conductivity of ZnO.