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A new strategy to synthesize a highly efficient CO(2) capturer by incorporating tetraethylenepentamine (TEPA) into as-synthesized MCM-41 (AM) is reported. The amine guest can be distributed in the micelle of the support, forming a web within the mesopore to trap CO(2) molecules and resulting in a high adsorption capacity for CO(2) up to 237 mg g(-1). Four samples of the as-synthesized MCM-41 with a different amount or type of surfactant are employed as supports to investigate the influence of micelles on the CO(2) adsorption, and the spokelike structure of the micelle in the channel of the support is proven to be essential to the distribution of guest amine. Among these supports, the AM sample is the most competitive due to the advantages of energy and time saving in preparation of the support along with the resulting higher CO(2) adsorption capacity. At the optimal loading of 50 wt % TEPA, the AM-50 sample exhibits a high adsorption capacity of 183 mg g(-1) in the sixth adsorption cycle at 5 % CO(2) concentration.

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The unique configuration of unpaired 4f and 5f electrons and the rich structures of their energy levels enable rare-earth metals to possess many particular physical and chemical properties, such as high electrical conductivity, large magnetic moment, and very high complexation reactivity. [1,2] Based on these properties, the rare-earth metals and compounds have been applied extensively in permanent magnets, [3] autocatalysts, [4] superconductors, [5] etc. Demand for high-purity rareearth oxides and rare-earth metals is expected to increase particularly for use in corrosion resistance, [6] heat storage and dispersal, [7] and also in environmentally friendly applications such as in pigments for paint and plastics, [8] in cement manufacture to reduce the temperature of calcination and help save energy, [9] and in refrigeration components arising from the search for chlorofluorocarbon (CFC) replacements.[10] For the nanoscale rare-earth metals, because of the significantly increased total surface area or the grain boundary area, some new features show in the crystal structures, interface, thermodynamics, and phase transitions. [11][12][13] Consequently, remarkably improved optical, electronic, magnetic, and catalysis properties can be expected. [14][15][16] However, because of the extremely high chemical reactivity and hence the considerably rigorous equipment requirements to preserve a high purity of the product, the preparation and characterization of nanostructured pure rare-earth metals are still big challenges in nanoscience and nanotechnology. Thus, many important features of nanoscale rare-earth metals, such as the physical, chemical, thermal, and mechanical characteristics have rarely been reported so far. The research corresponding to these characteristics is of great importance, however, both for the development of nanoscience and nanotechnology and for extending the applications of the rareearth metals. In this consideration, we demonstrate in the present work how to prepare nanostructured bulk materials of some typical members of the rare-earth metals, laying the foundation for characterizing the physical and chemical properties of nanoscale rare-earth metals.During the past two decades, a number of techniques have been developed to synthesize nanocrystalline bulk materials, such as inert gas condensation and consolidation, [17] electrodeposition, [18] severe plastic deformation, [19] crystallization of amorphous solids, [20] surface mechanical attrition, [21] and powder metallurgy. [22][23][24] However, it is hard to produce nanocrystalline materials with controllable grain sizes in a wide range below 100 nm. Furthermore, in powder metallurgy for the consolidation of nanoparticles, the grain size in the synthesized bulk is generally larger than the initial particle size. [22][23][24] Particularly, in conventional powder metallurgy processes, a rapid coarsening of nanoparticles occurs very often, leading to the formation of grains in the submicrometer or even micrometer range. Using a new "oxygen-free" (o...