Copper species were incorporated into SBA-15 by solid-state grinding precursor with as-prepared mesoporous silica (SPA). The obtained materials (CuAS) were well-characterized by XRD, TEM, N(2) adsorption, H(2)-TPR, IR, and TG and compared with the material derived from calcined SBA-15 (CuCS). Surprisingly, CuO up to 6.7 mmol·g(-1) can be highly dispersed on SBA-15 by use of SPA strategy. Such CuO forms a smooth layer coated on the internal walls of SBA-15, which contributes to the spatial order and results in less-blocked mesopores. However, the aggregation of CuO takes place in CuCS material containing 6.7 mmol·g(-1) copper, which generates large CuO particles of 21.4 nm outside the mesopores. We reveal that the high dispersion extent of CuO is ascribed to the abundant silanols, as well as the confined space between template and silica walls provided by as-prepared SBA-15. The SPA strategy allows template removal and precursor conversion in one step, avoids the repeated calcination in conventional modification process, and saves time and energy. We also demonstrate that the CuAS material after autoreduction exhibits much better adsorptive desulfurization capacity than CuCS. Moreover, the adsorption capacity of regenerated adsorbent can be recovered completely.

The windmill-like chiral nature of individual ZnPc molecules adsorbed on Cu(100) surface at room temperature has been revealed by scanning tunneling microscopy (STM) and the origin of such chirality is attributed to asymmetrical charge transfer between the molecules and the copper surface. Such chiral enantiomers do recognize each other in molecular level and spontaneously form second-level chiral supramolecular structures with the same chirality during thermally driven movements. The interactions between the ZnPc molecules during such chiral recognition process have been discussed based on the analysis of the sub-molecule-resolution STM images.

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Pd catalysts display excellent potential applications in H 2 O 2 direct synthesis from H 2 and O 2 . Facet dependence on catalytic selectivity for H 2 O 2 direct synthesis on Pd surfaces is investigated by the combination of DFT calculations and microkinetic study. It is found that the coadsorbed O plays a key role in catalytic activity and selectivity for H 2 O 2 direct synthesis on Pd(111) and Pd(100) surfaces. The coadsorbed O on Pd surfaces could not only increase the catalytic activity but also promote the catalytic selectivity on Pd surfaces. With the help of coadsorbed O, Pd(111) surface shows a very high selectivity (>99%) for H 2 O 2 products, but Pd(100) surface displays a high selectivity (>99%) for H 2 O formation. The role of proton transfer is also investigated in H 2 O 2 direct synthesis, and it is found that proton transfer reactions are harmful to H 2 O 2 formation. This work sheds light on the reaction mechanism of H 2 O 2 direct synthesis reaction on different Pd surfaces, and it may create a new path to understand the facet-dependent on catalytic selectivity.

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Deep desulfurization via π-complexation adsorption is a promising method for the purification of transportation fuels. The desulfurization performance of an adsorbent has been proven to strongly depend on the dispersion extent of adsorption active species. In this paper, we report a strategy to promote the dispersion of active species CuCl on mesoporous silica SBA-15 by incorporating alumina. By use of such a strategy, properties of the host SBA-15 were successfully adjusted. The enhancement of hostÀguest interaction and the improvement of surface hydrophilicity were realized simultaneously. Furthermore, the solid-state ion exchange between CuCl and formed Br€ onsted acid sites (H + ) was observed, which leads to the generation of isolated cuprous species. As a result, the dispersion of guest CuCl on the host was efficiently promoted. We also demonstrated that the obtained material, CuCl supported on SBA-15 incorporated with 10 wt % of alumina, can capture 0.240 mmol 3 g À1 thiophene, which is obviously higher than that over CuCl/SBA-15 (0.167 mmol 3 g À1 ). Our materials may provide a potential candidate for application in adsorptive desulfurization.

A novel π-complexation adsorbent is fabricated by grafting Cu(I)-containing molecule precursors onto β-cyclodextrin. The adsorbent provides a molecular-level dispersion of Cu(I), which is particularly beneficial to the adsorptive removal of aromatic sulfur thiophene, and is impossible to be realized through the conventional thermal method.

Understanding the condensation of the dimeric thiostannate­(IV) [Sn2S6]4– to SnS2 is of key importance for the development of solution processing of advanced tin­(IV) sulfide based electronic devices such as photovoltaics (e.g., Cu2ZnSnS4, CZTSSe) and thin-film transistors. Here, we report the crystal structure of tetraammonium thiostannate­(IV) trihydrate ((NH4)4Sn2S6·3H2O), which can be used as a more environmentally friendly alternative to the hydrazinium analogue in solution processed advanced tin­(IV) sulfide based electronic devices, e.g., CZTSSe. Hirshfeld surface analysis shows that crystal bound water molecules play a significant role in the structure and interact strongly with the sulfur atoms in the dimeric thiostannate­(IV) complex [Sn2S6]4–. The thermal decomposition and corresponding condensation of ((NH4)4Sn2S6·3H2O) to SnS2 have been studied by TG/DSC-MS and solid-state 119Sn MAS NMR. It involves the formation of the relatively more condensed thiostannate­(IV) complex [Sn4S10]4– at 90 °C via evaporation of ammonia, hydrogen sulfide, and water from the structure. With increasing temperature, more tin is transformed from tetrahedral to octahedral coordination, and at 220 °C, crystalline SnS2 is formed. In an aqueous ammonium sulfide based solution, the structure of dimeric [Sn2S6]4– is retained, and aqueous solutions of (NH4)4Sn2S6·3H2O can be spin coated and thermally decomposed to form crystalline SnS2 thin films. X-ray scattering techniques show that the solution processed SnS2 thin film is highly textured with the ab plane parallel to the substrate. Furthermore, AFM and TEM reveal that the thin film is continuous and with an inherent porous surface structure from the gaseous formation byproducts.