Zinc oxide in the form of nanoscale materials can be regarded as one of the most important semiconductor oxides at present. However, the question of how chemical defects influence the properties of nanoscale zinc oxide materials has seldom been addressed. In this paper, we report on the introduction of defects into nanoscale ZnO, their comprehensive analysis using a combination of techniques (powder X‐ray diffraction (PXRD), X‐ray absorption spectroscopy/extended X‐ray absorption fine structure (XAS/EXAFS), electron paramagnetic resonance (EPR), magic‐angle spinning nuclear magnetic resonance (MAS‐NMR), Fourier‐transform infrared (FTIR), UV‐vis, and photoluminescence (PL) spectroscopies coupled with ab‐initio calculations), and the investigation of correlations between the different types of defects. It is seen that defect‐rich zinc oxide can be obtained under kinetically controlled conditions of ZnO formation. This is realized by the thermolysis of molecular, organometallic precursors in which ZnO is pre‐organized on a molecular scale. It is seen that these precursors form ZnO at low temperatures far from thermodynamic equilibrium. The resulting nanocrystalline ZnO is rich in defects. Depending on conditions, ZnO of high microstructural strain, high content of oxygen vacancies, and particular content of heteroatom impurities can be obtained. It is shown how the mentioned defects influence the electronic properties of the semiconductor nanoparticles.

”Systematic errors”, namely, oxygen vacancy sites in ZnO, are the active centers for the hydrogenation of CO to give methanol. Nanocrystalline ZnO with a high density of oxygen vacancies was prepared from special organometallic precursors, and its catalytic properties for methanol synthesis were studied.

Nanocasting, the 3D-transformation of self-assembled organic nanostructures into hollow inorganic replicas under preservation of fine structural details has recently turned out to be a versatile tool, both for the synthesis of porous media with new pore topology as well as for the characterization of the assembled structures themselves. This review gives a review on recent work describing the potential and restrictions of nanocasting using surfactants, polymers, colloids as well as supramolecular tectons as porogens.

Self‐organization in aqueous media studied indirectly: The aqueous phase is solidified by a silica sol–gel process, and the supramolecular aggregate is 1:1 cast into a solid silica matrix. For the model‐system cyclodextrins it was shown that the cyclodextrin molecules self‐assemble into “wormlike” aggregates in the porous silica (see scheme). By using this template, porous materials were obtained with promising properties such as a uniform pore system and smooth walls.