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Graphical abstract Highlights • The MoP/CN samples exhibit superior activity in CO 2 reduction and H 2 evolution. • The CO 2 adsorption and conversion progress is well revealed in the photoreaction. • The efficient co-catalyst MoP facilitates the separation and transfer of charges. Abstract Photoreduction CO 2 to hydrocarbons and photosplitting water for H 2 production are the most promising, sustainable approaches for environmental pollution alleviation and solar-to-chemical energy conversion. However, developing low-cost, high efficient and stable photocatalysts remains a great challenge. Herein, we reported a novel visible-light activated MoP co-catalyst loaded g-C 3 N 4 photocatalyst for CO 2 reduction and water splitting under simulated irradiation firstly. Experimental results demonstrated that the composites were highly active and exhibited superior stability. The maximum CO and H 2 evolution rates of 0.92 μmol h−1 and 40.38 μmol h−1 were achieved on MoP/CN-15% catalyst, which were 4.5-fold and 74.5-fold higher than the pure g-C 3 N 4 , and the corresponding apparent quantum efficiencies (AQE) were 3.5% and 18.3% at 420 nm, respectively. In situ FTIR analysis disclosed the CO 2 adsorption and conversion progress, in which the COO− acted as a major intermediate. Furthermore, comprehensive characterization analysis revealed the introduction of MoP facilitated the separation and transfer of photogenerated electron-hole pairs, and the theoretical calculation by density functional theory (DFT) also confirmed that MoP could effectively separate the photoexcited charges from g-C 3 N 4. Combining with experimental and DFT calculations results, a new way to design cost-effective photocatalysts has been enlightened. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Fe 3 O 4 @PS-TMG was synthesized by immobilizing TMG onto the shell of nanohybrids. • The loading of TMG as well as surface property of catalyst can be well regulated. • The MPIC can stabilize soybean oil-in-methanol Pickering emulsion. • The MPIC exhibited higher catalytic activity for transesterification. Abstract A novel magnetic Pickering interfacial catalyst (MPIC) was developed and used for highly effective and clean production of biodiesel. The catalyst was synthesized by immobilization of 1,1,3,3-tetramethylguanidine (TMG) onto the shell of Fe 3 O 4 @Chloromethyl PS nanohybrids. The resultant Fe 3 O 4 @PS-TMG was measured by transmission electron microscope (TEM), dynamic lighting scattering (DLS), Fourier transform infrared spectroscopy (FTIR), elemental analysis (EA), thermogravimetric analysis (TG), contact angles (CA). The results showed that surface property and TMG loading of catalyst can be finely regulated via adjusting the feeding of TMG. Fe 3 O 4 @PS-TMG with amphiphilic surface can stabilize soybean oil-in-methanol Pickering emulsion, which would offer large interfacial area and surface enrichment of reactants, leading to a significant enhancement of such liquid-liquid (L-L) biphasic reaction with high mass transfer resistance. Furthermore, the MPIC can be facile separated from the mixture of reaction by magnet, and showed excellent stability over 5 recycles. [ABSTRACT FROM AUTHOR]

We report herein the design and preparation of novel magneto-polymeric nanohybrids that can be used as efficient and recyclable Pickering interfacial catalyst (PIC) in selective oxidation of alcohols. The nanohybrids Fe 3 O 4 @SiO 2 @PTMA, bearing catalytic TEMPO functionalities, were synthesized through distillation-precipitation polymerization (DPP) of the precursor monomer 2,2,6,6-tetramethyl-4-piperidyl methacrylate (TMPM) and subsequent oxidation reaction. TEM, FT-IR, DLS, EA confirmed and quantified the TEMPO loading of nanohydrids (1.0–2.4 mmol · g −1 ). It was found that the TEMPO loading, particle size, as well as surface hydrophilicity could be finely tuned via simply adjusting the TMPM monomer fraction during polymerization. The performance of the resultant nanohybrids as PIC was then evaluated in a typical Anelli system, which showed superior catalytic activity for selective oxidation of alcohols. Moreover, the PIC can be easily recycled by applying magnetic field, and reused for the following cycles of oxidation without any loss on either conversion or selectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] As a renewable green energy, hydrogen has received widespread attention due to its huge potential in solving energy shortages and environment pollution. In this paper, a one-step solvothermal method was applied to grow ultra-thin g-C 3 N 4 (UCN) nanosheets and NiS nanoparticles on the surface of ZnIn 2 S 4 (ZIS). A ternary NiS/ZnIn 2 S 4 /ultra-thin-g-C 3 N 4 composite material with dual high-speed charge transfer channels was constructed for the advancement of the photocatalytic H 2 generation. The optimal ternary catalyst 1.5wt.%NiS/ZnIn 2 S 4 /ultra-thin-g-C 3 N 4 (NiS/ZIS/UCN) achieved a H 2 evolution yield reached to 5.02 mmolg−1h−1, which was 5.23 times superior than that of pristine ZnIn 2 S 4 (0.96 mmolg−1h−1) and even outperform than that of the best precious metal modified 3.0 wt%Pt/ZnIn 2 S 4 (4.08 mmolg−1h−1). The AQY at 420 nm could be achieved as high as 30.5%. The increased photocatalytic performance of NiS/ZIS/UCN could be ascribed to the type-I heterojunctions between intimated ZIS and UCN. In addition, NiS co-catalyst with large quantity of H 2 evolution sites, could result in efficient photo-induced charges separation and migration. Furthermore, the NiS/ZIS/UCN composite exhibited excellent H 2 evolution stability and recyclability. This work would also offer a reference for the design and synthesis of ternary co-catalyst with heterojunction composite for green energy conversion. [ABSTRACT FROM AUTHOR]

Atom transfer radical polymerization (ATRP) has been considered to be an efficient strategy for constructing functional macromolecules owing to its simple operation and versatile monomers, and thus it is of great significance to develop ideal catalysts with higher activity and perfect reusability. We constructed a peroxidase mimic through the grafting of heme onto metal-organic frameworks UiO-66-NH 2 (ZrMOF), namely Heme-ZrMOF. After the systematic characterization of structure, the composite Heme-ZrMOF was demonstrated to possess high peroxidase activity using 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonate) and 3,3′,5,5′-tetramethylbenzidine as substrates. The enzyme mimic was then used as catalysts in the ATRP reactions of different monomers, in which favorable monomer conversion (44.6–98.0%) and product molecular weight (8600–25,600 g/mol) could be obtained. Compared to free heme, Heme-ZrMOF could efficiently achieve the easy separation of heme from the catalytic system and facilitate the ATRP reaction in an aqueous environment to avoid the utilization of organic solvents. In conclusion, the enzyme mimic Heme-ZrMOF could be potentially used as an effective catalyst for preparing well-defined polymers with biomedical applications. [ABSTRACT FROM AUTHOR]