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[Display omitted] • The adsorption energies of CO 2 on the surface oxygen vacancies of different crystalline In 2 O 3 were calculated using DFT. • The effect of the spatial distributions of two active components on the CO 2 hydrogenation to aromatics was studied. • The acidity of catalyst under different spatial distributions was studied through NH 3 -TPD. In tandem catalysts, not only good synergy between the two active components is required, but also the precise control of the spatial distribution between the two active components of metal oxides and zeolite is crucial for the migration and conversion of reaction intermediates in the direct conversion of CO 2 to hydrocarbons. The correlation between the metal and the acidic site of zeolite has traditionally been simplified as "the closer, the better". However, it should be noted that this principle only holds true for a portion of tandem catalysts. Therefore, this paper studied the effect of different crystalline In 2 O 3 (cubic phase, hexagonal phase, and mixed cubic/hexagonal phase) and sheet HZSM-5 zeolite tandem catalysts on the activity of CO 2 hydrogenation reaction under different spatial distribution. The generalized gradient approximation (GGA) of density functional theory (DFT) were used to simulate the adsorption energy of CO 2 by oxygen vacancy on c-In 2 O 3 (1 1 1) and h-In 2 O 3 (1 0 4) planes, it was found that O v1 on c-In 2 O 3 (1 1 1) and O v4 on h-In 2 O 3 (1 0 4) had the strongest adsorption energy for CO 2. In addition, it has been observed that the proximity of the two active components (e.g., during mortar mixing) results in decreased catalytic performance. This is due to the migration of metal In, which neutralizes the acid sites of zeolites and leads to inefficient conversion of methanol reaction intermediates to aromatics. As a result, CO 2 conversion and aromatic selectivity are decreased. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co-catalytic effect of 1 T-MoS 2 greatly enhances the efficiency of photo-Fenton degradation. • The degradation efficiency of MB and RhB both reached 99.8% in 18 min. • The ·OH and visible light have synergistic in the photo-Fenton degradation system. • Density functional theory (DFT) was used to simulate the adsorption energy of H 2 O 2. Right here, flower-like FeMoO 4 @1T-MoS 2 composites were prepared by modifying FeMoO 4 microspheres with two-dimensional lamellar 1T-MoS 2 as co-catalyst, which was used for photo-Fenton catalysis degradation of binary dyes mixed with methylene blue (MB) and rhodamine B (RhB). Then various parameters affecting the generation of ·OH in the system were investigated. Systematic research shows that the degradation efficiency of MB and RhB can reach 99.8% in 18 min when the Mo/Fe molar ratio of the composite is 1:1. Furthermore, these experiments data were fitted by pseudo-first order kinetics model and pseudo-second order kinetics model. Subsequently the density functional theory (DFT) simulation results showed that FeMoO 4 exhibited excellent adsorption for H 2 O 2 , and the introduction of 1T-MoS 2 played a certain role in the adsorption and activation of H 2 O 2. Finally, the degradation pathways of MB and RhB were proposed to determine intermediates during photo-Fenton process by LC-MS and the reaction mechanism was detailed investigated by quenching experiment of active free radicals. FeMoO 4 @1T-MoS 2 has also excellent stability and highlights the potential and prospect of the composite for dye wastewater treatment. [ABSTRACT FROM AUTHOR]

Pressure-driven and lower flux of superwetting ultrafiltration membranes in various emulsions separation are long-standing issues and major barriers for their large-scale utilization. Even though currently reported membranes have achieved great success in emulsions separeation, they still suffer from low flux and complex fabrication process resulting from their smaller nanoscale pore size. Herein, utilizition of coconut shell as a novel biomaterial for developing into a layer through the simple smashing, cleaning and stacking procedures, which not only could avoid the complexity of film making process, but also could realize efficient gravity-directed separation of both immiscible oil/water mixtures and water-in-oil emulsions with high flux. Specifically, the layer acted as “water-removing” type filtrate material with excellent underwater superoleophobicity, exhibiting high efficiency for various immiscible oil/water mixtures separation and larger oil intrusion pressure. More importantly, the layer could also serve as adsorbent material with underoil superhydrophilicity, achieving gravity-directed kinds of water-in-oil emulsions separation with high separation efficiency (above 99.99%) and higher flux (above 1620 L/m 2 h), even when their pore sizes are larger than that of emulsified droplets. We deeply believe that this study would open up a new strategy for both immiscible oil/water mixtures and water-in-oil emulsions separation. [ABSTRACT FROM AUTHOR]

Elemental doping has been proven to be an effective strategy for increasing the catalytic activity and structural stability of Fenton catalysts. Therefore, this work reports that Mn-doped FeS 2 /Fe 2 O 3 (Mn 3 O 4 –FeS 2 /Fe 2 O 3) has excellent catalytic performance for the degradation of Orange II under simulated solar energy. Degradation experiment results showed that the sample with a manganese-iron molar ratio of 1:2 exhibited higher activity than others. The degradation rate of 20 mg/L OII reached 99.0% in 18 min under the conditions of 0.3 g/L Mn 3 O 4 –FeS 2 /Fe 2 O 3 , 5 mM H 2 O 2 and pH = 2.8. In addition to, the Mn 3 O 4 –FeS 2 /Fe 2 O 3 catalyst shows good reusability for Orange II and high activity for other dyes (MB, MG, Rh B and MO) under optimal conditions. Degradation mechanism study indicated that the heterogeneous Fenton reaction was promoted by retarding the recombination of photogenerated charge carriers and accelerating the cycle between Fe3+/Mn2+ and Fe2+/Mn3+, which improved photo-Fenton-like catalytic performance, resulting in the enhanced degradation of organic pollutant. Finally, a possible degradation pathway was proposed according to the results of liquid chromatography-mass spectrometry (LC-MS). In short, the catalyst has potential application value in wastewater treatment. • The degradation of Orange II by Mn 3 O 4 –FeS 2 /Fe 2 O 3 attained to 99.0% in 18 min. • Both.•OH and •O 2 − played important roles in the degradation process. • The photo-Fenton-like catalytic performance of the Mn 3 O 4 –FeS 2 /Fe 2 O 3 catalyst was enhanced. • The catalyst maintained excellent reusability for Orange II and high activity for other dyes. [ABSTRACT FROM AUTHOR]