Question

The band gap between the valence and the conduction bands in zinc oxide (ZnO) is 3.2 eV. Suppose an electron in the conduction band combines with a hole in the valence band and the excess energy is released in the form of electromagnetic radiation. Find the maximum wavelength that can be emitted in this process.

Answer 1

Given Band gap = 3.2 eV

$E=\frac{hc}{\lambda }=\frac{1242}{\lambda }=3.2$

or $\lambda =388.1nm$