Nanoporous adsorbents of ZnO/ZnFe2O4/C were synthesized by using a metal organic framework (Fe(III)-modified MOF-5) as both the precursor and the self-sacrificing template. The adsorption properties of ZnO/ZnFe2O4/C toward Pb(ii) ions were investigated, including the pH effect, adsorption equilibrium and adsorption kinetics. The adsorption isotherms and kinetics were well described by using the Langmuir isotherm model and pseudo-second-order model, respectively. The MOF-derived inorganic adsorbents exhibited high absorption performance with a maximum adsorption capacity of 344.83 mg g(-1). X-ray powder diffraction and high-resolution X-ray photoelectron spectroscopy suggest that Zn(ii) was substituted by a significant portion of Pb(ii) on the surface of ZnO nanocrystals. Microscopic observations also demonstrate the effect of Pb(ii) ions on ZnO crystals as reflected by the considerably reduced average particle size and defective outer layer. Quantitative measurement of the released Zn(ii) ions and the adsorbed Pb(ii) ions indicated a nearly linear relationship (R(2) = 0.977). Moreover, Pb-containing ZnO/ZnFe2O4/C adsorbents are strongly magnetic allowing their separation from the water environment by an external magnet.

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One‐dimensional magnetite/manganese iron oxide modified by carbon coating and with TiO2 nanoparticles into core–shell composite nanofibers (FMO/C@TiO2) with porous structure were fabricated using organometallic compounds as templates. The structure and physicochemical properties of the as‐obtained composite nanofibers were characterized by a series of techniques, including X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, nitrogen adsorption–desorption isotherms, X‐ray photoelectron spectroscopy and UV/Vis diffuse reflectance. The results demonstrate that the one‐dimensional core–shell structure was formed by coating TiO2 nanoparticles onto a substrate of FMO/C nanofibers. The porous nanostructures and photoresponse range of the composite nanofibers can be controlled by varying the proportion of both template and titanium source. The resultant composite nanofibers exhibited highly efficient removal of dye from wastewater by combining adsorption and photocatalysis processes. In addition, the composite nanofibers are superparamagnetic, and can be recovered by magnet easily with almost no decline in the removal efficiency. The facile synthesis strategy used here might provide a universal and efficient method to fabricate one‐dimensional magnetic nanocomposites with porous structures for various functional applications.