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A mesoporous Pd(II) organometallic catalyst is synthesized by coordinating the Pd(II) with the amine-ligand anchored on ethyl-bridged PMOs. During Barbier reaction in water as an environmentally friendly medium, the as-prepared Pd(II)-PMOs (Et) exhibits matchable catalytic activity and selectivity with the corresponding homogeneous Pd(II) catalyst and could be used repetitively for more than 5 times, which could reduce the cost and even diminish the environmental pollution from heavy metallic ions, showing a good potential in industrial applications. On one hand, the excellent catalytic performance could be attributed to the high surface area and ordered mesporous structure of the PMOs support, which ensures the higher dispersion of Pd(II) active sites and also facilitates the diffusion of reactant molecules. On the other hand, the ethyl fragments embedded in the pore walls could enlarge mesopores and also enhance surface hydrophobility of the PMOs support, which further promotes the diffusion and adsorption of organic molecules, especially in aqueous medium, leading to higher activity and selectivity.

A novel indium-boron (In-B) amorphous alloy was prepared by chemical reduction of indi-À ] in aqueous solution and was applied to the water-medium Barbier-type allylation reactions. A variety of allyl halides could be efficiently added to aldehydes or ketones in water. Additionally, the as-prepared In-B exhibits much higher activity than the commercial In powder and the crystallized In-B owing to the high surface area, the unique amorphous alloy structure, and the high electron density on the In active sites resulting from the strong electronic interaction between the metal In and the alloying B. The yield of target product over the In-B amorphous alloy was similar to that obtained on the homogeneous Pd(II) organometallic catalyst, showing good potential in practical application.

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A g-C3N4/TiO2 heterojunction functional foams were constructed as gas purification filter for treating NO indoor gas with high removal rate (> 65 %) and high stability under visible-light (λ ≥...

Hierarchically ordered porous silica materials (HSMs) with a micro/mesoporous structure were successfully prepared with the sol-gel method using dextran, dextran/CTAB, and CTAB as templates. The obtained hierarchically structured silica was successfully modified with amine groups through post-grafting and one-pot methods. Their architectural features and texture parameters were characterized by XRD, N2 adsorption–desorption isotherms, SEM, TEM, FTIR, and TGA techniques. The results demonstrated that the pore structure depended on the reaction temperature and the amount of CTAB added in the synthesis procedure. A series of porous silica with hierarchical pore structures possessed abundant micropores, ordered mesopores, and a tunable surface area and pore volume. After modification, the ordered structure of the hierarchical porous silica almost disappeared due to the presence of amine groups in the pore channel. Furthermore, to explore the effect of pore structures and amine groups on CO2 adsorption performance, before and after amine modification of HSMs, adsorbents were evaluated regarding the capacity of collecting CO2 for comparison. According to these results, the varying microporous content, pore size distribution, and density of the amine groups were important factors determining the capacity of CO2 capture.

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Photocatalysis and photoelectrocatalysis, as green and low-cost pollutant treatment technologies, have been widely used to simultaneously degrade pollutants and produce clean energy to solve the problems of environmental pollution and energy crisis. However, the disadvantages of photocatalysts in a narrow absorption range and low utilization rate of solar energy still hinder the practical application. Here we fabricate two-dimensional porous Ruddlensden–Popper type nickel-based perovskite oxide La2NiO4 as a noble metal-free photoanode for photoelectrocatalytic urea oxidation under full spectrum sunlight irradiation. The transient photocurrent density under near infrared (NIR) light (λ > 800 nm) can reach 50 μA cm−2. Urea wastewater was used as the fuel to obtain low-energy hydrogen production, and round-the-clock hydrogen production was achieved with the optimal yield of 22.76 μmol cm−2 h−1. Moreover, a photocatalytic urea fuel cell (PUFC) was constructed with La2NiO4 as the photoanode. The power density under UV-vis-NIR was 0.575 μW cm−2. Surprisingly, the filling factor (FF) under NIR light was 0.477, which was much higher than those under UV-vis-NIR and visible light. The results demonstrated that PUFCs constructed from low-cost nickel-based perovskite oxides have potential applications for low-energy hydrogen production and efficient utilization of sunlight.