Photocatalytic Activity Under UV and Solar Illumination of Thin ZnO Films Grown by Atomic Layer Deposition

Abstract

The photocatalytic activity of thin zinc oxide (ZnO) films grown by atomic layer deposition (ALD) and plasma-enhanced ALD (PEALD) was investigated under UV and simu-lated solar illumination. Optimal deposition temperatures were chosen for each method (200°C for ALD and 60°C for PEALD). Under UVC light, the PEALD ZnO thin film showed higher photocatalytic activity, while the activity of the ALD film was better under sun-simulating light. At UVA, the results were similar for the two types of thin films. We have shown that the photocatalytic activity depends on both optical properties and crystal structure, with neither of them having a dominant impact.