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In this paper, we have synthesized meso-oxides (i.e., Co₃O₄ and NiO) by using mesoporous silica as hard template. The microstructures and chemical compositions of the corresponding meso-oxides were characterized by the Transmission electron microscope-selected area electron diffusion (TEM-SAED), X-ray diffraction (XRD), scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDS), respectively. And, their electromagnetic and microwave absorption properties were investigated in the frequency range of 2–18 GHz. The results indicate that meso-oxide templated from KIT-6 (i.e., meso-K–Co/Ni) exhibit a dual absorption characteristic compared with those using SBA-15 as hard template. This phenomenon suggests that meso-oxides templated from SBA-15 and KIT-6 can exhibit different microwave absorption behaviors due to their respective microstructures.

In this paper, we review on classes of materials that can be used as hard templates to fabricate nanostructured thin film materials. The hard templates discussed are anodized aluminum oxide (AAO), block copolymer (BC) self-assembly films, and mesoporous thin films (MTFs), with emphasis on MTFs since it has not been reviewed for the application as templates while the first two materials have been reviewed previously by others. Each one of the three classes of templates has advantages and drawbacks. Considering the pore dimensions available by each one of them, the three templates are complementary to one another. Some of the features of MTFs appear to be advantageous over the other types of templates. All and all, these three appear to have complementing features to cover the various aspects required for templates to synthesize nanostructured thin films.