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Formaldehyde is regarded as the major indoor pollutant emitted from widely used building and decorative materials in airtight buildings, which should be eliminated under indoor environmental conditions. We report here catalytic oxidation process of formaldehyde over mesoporous Co(3)O(4), Co(3)O(4)-CeO(2), Au/Co(3)O(4), and Au/Co(3)O(4)-CeO(2) catalysts and their excellent catalytic performances at room temperature. These catalysts were prepared by a "nanocasting" method with the mesostructure generated from SBA-15 silica with 2D structure. The adsorbed surface species in the formaldehyde oxidation process are analyzed, and some key steps in the oxidation pathway, active sites, and intermediate species are proposed. Among the detected species, some kinds of formate species formed on the catalysts were indentified as intermediates, which further transformed into bicarbonate or carbonate and which decomposed to carbon dioxide. The role of the mesoporous Co(3)O(4) and the gold nanoparticles in the mechanism are also revealed.

The separation of H 2 S/CH 4 mixture was computationally examined in the composites of ionic liquids (ILs) supported on metal-organic frameworks (MOFs) at room temperature. Cu-TDPAT was selected as supporter for four types of ILs combined from identical cation [BMIM] + with different anions ([Cl] -, [Tf 2 N] -, [PF 6 ]and [BF 4 ] -). The results show that introducing ILs into Cu-TDPAT can greatly enhance the adsorption affinity towards H 2 S compared to the pristine MOF, and the strongest enhancement occurs in the composite containing the anion [Cl]with the smallest size. The H 2 S/CH 4 adsorption selectivities of each composite are significantly higher than those of the pristine Cu-TDPAT within the pressure range examined, and the selectivity generally shows an increasing trend with increasing the loading of the IL. By further taking the H 2 S working capacity into account, this work also reveals that the [BMIM][Cl]/Cu-TDPAT composite exhibits the best separation performance in both VSA and PSA processes. These findings may provide useful information for the design of new promising IL/MOF composites applied for H 2 S capture from natural gas. smaller. As a result, taking the working capacity and selectivity into account, it can be concluded that the [BMIM][Cl]/Cu-TDPAT composite with a loading of 25 IL molecules has the best properties for H 2 S/CH 4 separation in both the VSA and PSA processes. CONCLUSIONSMolecular simulations have been performed to investigate the performance of IL/Cu-TDPAT composites for the separation of H 2 S/CH 4 mixture. The ILs considered in this work are composed of identical cation [BMIM] + and four types of anions ([Cl] -, [Tf 2 N] -, [PF 6 ]and [BF 4 ] -) with a large diversity in chemical property, shape and size. The results show that the anions of the ILs are preferentially located near the Cu atoms of the MOF framework, while the cations are located near the organic linkers. The adsorption affinity towards H 2 S is significantly enhanced by incorporating each IL into the pores of Cu-TDPAT, with the highest heat of adsorption in the composite containing the anion [Cl]with the smallest size. In addition, this work demonstrates that the [BMIM][Cl]/Cu-TDPAT composite exhibits the best separation performance in both VSA and PSA processes, by taking both the adsorption selectivity and working capacity into account. On the basis of the results obtained in current study, it can be expected that the use of MOFs as the supporter for ILs is an alternative efficient strategy to generate new promising adsorbents for practical H 2 S separation related to natural gas purification. ASSOCIATED CONTENT Supporting Information. Details of the force field parameters, structures of some IL/Cu-TDPAT composites, and some simulation results. This material is available free of charge via the Internet at

IL-induced formation of dynamic complex iodide anions in IL@MOF composites facilitates record iodine adsorption capacities for both iodine vapor and solution.