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The ligand structure and optimized calcination temperature and time of Zn-MOF produced carbon encapsulated ZnO nanostructure that showed excellent dye adsorption from water. [Display omitted] • Synthesis of nitrogen doped carbon encapsulated ZnO hybrid nanostructures from Zn-MOFs. • Optimizing the reaction condition and ligand structure for ZnO preparation. • Enhanced cationic dye adsorption by ZnO-NC hybrid nanostructures. • Removal of dyes by filtration through ZnO hybrid nanostructures as column packing materials. • Kinetics and adsorption isotherm models were evaluated. Water pollution by organic dyes poses great challenge to the environment as well as living organisms. Herein, we have fabricated nanoplates of ZnO in carbon matrix by controlled calcination of zinc-metal organic frameworks (Zn-MOFs) and used as adsorbents for efficient removal of organic dyes from water. Zn-MOF of phthalic acid and 5-nitrophthalic acid produced nanoplates of ZnO (ZnO-C and ZnO-NC) in carbon matrix without and with nitrogen doping. The fabricated hybrid nanostructures were characterized using PXRD, FTIR, BET, TGA, HR-SEM, HR-TEM and XPS analysis. Both ZnO-C and ZnO-NC showed high adsorption of cationic dyes (crystal violet (CV), methylene blue (MB) and Rhodamine B (Rh B)) compared to anionic dyes (methyl orange (MO) and Eosin yellow (EY)). Nitrogen doped ZnO-NC exhibited relatively higher percentage of dyes removal (99 %) compared to ZnO-C. Interestingly, ZnO-NC showed high adsorption of MB dye across the pH range from acidic (pH = 3.0) to alkaline (pH = 11.0). The zero-point charge indicated the negative surface charge for ZnO-NC/ZnO-C that facilitated electrostatic interactions between dyes and adsorbents. Adsorption kinetics suggested a pseudo second order model and adsorption isotherm fitted well with the Freundlich model, suggesting heterogenous adsorption with multilayer coverage of dye molecules. The reusability of ZnO-NC showed only slight reduction of adsorption in three successive cycles. Further, ZnO-NC was used as column packing materials for the successful removal of both cationic as well as anionic dyes upon filtration. Thus, the present studies provided insight on the organic ligand structure and calcination temperature of MOFs for transforming them into effective organic dye adsorbent. [ABSTRACT FROM AUTHOR]