Hierarchical ZnO nanosheets/nanodisks hydrothermally grown on microrod backbones

We synthesized hierarchical ZnO nanosheets/nanodisks on microrod backbones via a hydrothermal process using trisodium citrate as a mediator. The trisodium citrate facilitated the formation of the nanosheet structure and induced dramatic transformation to nanodisk structure as reaction time elapses. The morphological, optical, and photocatalytic properties of ZnO nanosheets, nanosheets/nanodisks, and nanodisks coated microrods (NSMR, NSDMR, and NDMR) were investigated. The hierarchical structures on the MR were changed from N-S, N-SD, to N-D with reaction time by crystallization, dissolution, and precipitation processes. The NDMR had a lower defect density and exhibited a better photocatalytic performance than the NSMR and NSDMR due to its excellent charge transfer. (C) 2016 Elsevier B.V. All rights reserved.