Effect of Surface and Defect Chemistry on the Photocatalytic Properties of Intentionally Defect-Rich ZnO Nanorod Arrays.

Due to the abundance of intrinsic defects in zinc oxide (ZnO), the material properties are often governed by same. Knowledge of the defect chemistry has proven to be highly important, especially in terms of the photocatalytic degradation of pollutants. Given the fact that defect-free materials or structures exhibiting only one type of defect are extremely difficult to produce, it is necessary to evaluate what influence various defects may have when present together in the material.

Defect-promoted photo-electrochemical performance enhancement of orange-luminescent ZnO nanorod-arrays.

Intentionally defect-rich zinc oxide (ZnO) nanorod-arrays were grown from solution by carefully adjusting the concentration ratio of the growth-precursors used followed by various post-deposition thermal treatments. Post-deposition rapid thermal annealing (RTA) at moderate temperatures (350 °C-550 °C) and in various atmospheres was applied to vary the defect composition of the grown nanorod-arrays. It is demonstrated that, intense, defect-related orange emission occurs solely upon RTA around 450 °C and is essentially independent of the atmosphere used.