Comparison of ZnO nanorod array coatings on wood and their UV prevention effects obtained by microwave-assisted hydrothermal and conventional hydrothermal synthesis

Abstract ZnO nanorod array coatings were successfully synthesized on wood surfaces using a conventional hydrothermal (CHT) and a microwave-assisted hydrothermal (MWHT) method. The reaction time of the MWHT method at high temperature was only 1/12th that of the CHT method. The MWHT-ZnO nanorods exhibited better crystallinity than those produced by the CHT method. The ZnO nanorod had a wurtzite crystal structure oriented along the c -axis. The MWHT nanorods with their higher (002)/(101) ratio were more conducive and improved the orientation degree of the ZnO nanorods. Field emission scanning electron microscopy (FE-SEM) images showed that the MWHT-ZnO nanorods had smaller diameters and narrower size distributions than those produced by the CHT method. However, both methods formed well-aligned array coatings that covered the wood surfaces, and the two coatings had similar UV protecting effects and inhibited discoloration.