ABSTRACT
Till now, many useful methods and techniques have been developed for the pollution remediation. Among them, removal of pollutants by the method of adsorption and/or catalysis using adsorptive and/or catalystic materials is an important and effective way. In this case, the key issue is the high efficiently absorptive and/or catalystic materials. The materials with high surface activity, high specific surface area, strong selective adsorption, and stable structure are expected. Although the nanosized particle powders could be the candidate for such materials for their high surface area and surface activity [2-9], they are very easily aggregated, leading to the unwanted reduction in the active surface area and surface activity, and hence the bad reusable property. In addition, the used nanosized adsorbents or photocatalysts are suspended in the solution and difficult to separate from bulk solution. Micro/nanostructured materials, which are composed of the microsized objects with nanostructures [10,11], could overcome such disadvantages. The microsized objects could resist aggregation and the nanostructure could supply high surface area and surface activity during usage. Therefore, these materials with micro/nano-architectures not only possess large surface to-volume ratio, high structural stability against aggregation, and are very easily separated from solution during application in the pollution remediation, but also exhibit strong structurally enhanced adsorption and catalysis performances, and hence can be used for high efficient removal of contaminants in water or solutions. In this chapter, we will introduce some recent progresses in this area at our lab, mainly including mass production of new micro/nanostructured materials for adsorbents; structurally enhanced catalysis properties; and structurally enhanced and selective adsorption performances. 9.2 Mass Production of Novel Micro/
Nanostructured MaterialsMass production of the micro/nanostructured materials plays an important role in their applications in environmental remediation. There have been many methods developed for such micro/nanos-
tructured materials. Here, we will only introduce solvothermal/hy-drothermal (soft template), template-etching (hard template), and electrospinning methods. 9.2.1 Solvothermal/Hydrothermal Method Solvothermal/hydrothermal method is known for its low cost, easy operation, and easy control for preparation of micro/nanostructured materials. The general strategy is illustrated in Fig. 9.1. Briefly, structural directors (surfactants or organic solvents) are added in the precursor solution and then maintained at 150oC-250oC for reaction. Metal oxides or sulfides with novel micro/nanostructures are then obtained after reaction for a certain time (several hours) or subsequent heat treatment.
