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Aiming at the comprehensive utilization of waste and renewable carbon resources, we achieved a photocatalytic coupling process of CO2 reduction and 5-hydroxymethylfurfural oxidation mediated by the anionic compound of layered double hydroxides.

The ZnO/BiVO4/NiFePB photoanode was fabricated successfully and showed the excellent performance of PEC water oxidation compared with the ZnO photoanode, which is attributed to the formation of a heterojunction and decoration of NiFePB cocatalyst.

The low carrier mobility of BiVO4 is a bottleneck that limits its charge transfer in bulk or on the surface. Herein, reduced graphene oxide (rGO) nanosheets as an effective electron mediator were successfully loaded on BiVO4 and NiFe-layered double hydroxides (NiFe-LDHs) were decorated on BiVO4/rGO heterojunctions by two facile electrodeposition methods to construct a triadic photoanode of BiVO4/rGO/NiFe-LDH for improvement of photoelectrochemical (PEC) water splitting efficiency of BiVO4. This photoanode significantly extends the absorption region of visible light, increases the photocurrent density, exhibits an onset potential with a significant cathodic shift, and enhances photon-to-electron conversion efficiency (IPCE) compared with the pristine BiVO4 photoanode. The enhancement of PEC properties benefits from the formation of p-n heterojunctions between rGO and BiVO4 and the use of NiFe-LDH as a cocatalyst for accelerating the kinetics of oxygen evolution from water.

Two kinds of UV absorbers 2-hydroxy-4-methoxy-benzophenone-5-sulphonic acid (HMBA) and cinnamic acid (CA) were successfully co-intercalated into the interlayer of Mg2ZnAl layered double hydroxides (LDH) by a modified coprecipitation method to prepare novel UV-shielding material HMBA-CA-LDH for improving the anti-photoaging capability of polypropylene (PP). The characterization results reveal the presence of host-guest interactions between the LDH host layers and HMBA/CA guest anions as well as guest-guest interactions between guest anions in HMBA-CA-LDH, and the HMBA-CA-LDH has much stronger UV absorption capability than the HMBA intercalated LDH (HMBA-LDH) in the whole UV band and a much broader UV absorption band than the CA intercalated LDH (CA-LDH). A series of LDH/PP composites with evenly dispersed LDH nanosheets were prepared by incorporating the prepared LDHs into the matrix of PP via the solvent casting method. As expected, LDH/PP composites show higher thermal stability and better anti-photoaging ability than pristine PP. Interestingly, HMBA-CA-LDH/PP shows better anti-photoaging performance in comparison with HMBA-LDH/PP and CA-LDH/PP because of its better UV-shielding ability arising from the synergistic UV-shielding effects of both HMBA and CA, and the HMBA-CA-LDH can reduce the photodegradation of PP by about 85%. Hence, the prepared novel HMBA-CA-LDH has potential application in the field of PP as an efficient and promising UV-shielding material.

The base-free styrene epoxidation with H2O2 as an oxidant was strongly in accordance with the requirements for a sustainable chemical industry. Aiming at the low efficiency of a non-noble metal catalyst system, we proposed utilizing the synergistic effect and manipulating the surface acid–basic property of materials to increase the catalytic performance in this reaction. Herein, to combine two promoting approaches, we synthesized a series of mixed metal oxide (MMO) materials to screen promising active components with a suitable acid–basic property for H2O2–styrene epoxidation. As a result, the highest styrene conversion (82.8%) and best styrene oxide selectivity (79.7%) were achieved over a CuCr-MMO catalyst. The catalytic performance was considerably enhanced compared with the CuO and CrOx references. Detailed characterizations were performed to investigate the dispersion, electronic structure, and acid–basic property to explain the structure–performance relationship. On one hand, the promoted dispersion of the Cu and Cr components contributed to more catalytic sites and the electron transfer between Cu and Cr improved the intrinsic activity, which were both responsible for the enhanced activity. On the other hand, the unique structure modulated the acid–basic properties to be suitable for this catalytic system. In particular, a suitable basicity was facilitated to selectively transform H2O2 into HOO˙ radicals, while a low acidity suppressed the epoxide ring opening to form phenylacetaldehyde. By combining the high accessibility, suitable basic–acid property, and fast electron transfer, CuCr-MMO exhibited a high styrene conversion and selectivity to styrene oxide.

International audience; High-performance heat-retention agents for multifunctional green agricultural films are today largely suitable to increase the production yield as well as to save energy. Here, an adapted ammonia releasing hydrothermal method was used to produce a series of micrometer-sized carbonate-layered double hydroxide (CO3-LDH) precursors of sizes ranging from 1.32 μm to 8.64 μm by simply adjusting the feeding Mg2+ concentration from 0.80 mol L−1 to 0.20 mol L−1. From these pristine LDH materials, μm-sized dihydrogenphosphate-intercalated LDHs (H2PO4-LDHs) were prepared by an anion-exchange method. The structure, the platelet size, and the associated selective IR absorption properties of the H2PO4-LDH and the derivative H2PO4-LDH/EVA composite as well as the related visible transmittance and the photostability of the H2PO4-LDH/EVA film were investigated. The results show that the selective IR absorption in the wavelength range of 7–14 μm enabling the heat retention of the H2PO4-LDHs and H2PO4-LDH/EVA composites depends on the corresponding number-averaged particle size of H2PO4-LDH in the range of 2.01 μm to 8.80 μm. Compared with EVA, the H2PO4-LDH/EVA composites demonstrate a significant improvement of selective IR absorption, while maintaining acceptable visible transmittance, and similar photostability. An optimized particle size of H2PO4-LDH of ca. 5.85 μm leads to 60% selective IR absorption and 64% selective IR absorption when dispersed in EVA, while the polymer free of filler exhibits less than 50% absorption in the 7–14 μm IR domain.

Au–Pd nanoalloys supported on Mg–Al mixed metal oxides prepared using sol-immobilisation are found to be highly efficient and reusable catalysts for the solvent-free oxidation of benzyl alcohol using molecular oxygen under low pressure. When using this support alloying Pd with Au resulted in an increase in both activity and selectivity to benzaldehyde and moreover an improved resistance to catalyst deactivation compared with the monometallic Pd and Au catalysts. The turnover number for the Au/Pd 1 : 1 molar ratio catalyst achieved 13 000 after 240 min and the selectivity to benzaldehyde was maintained at 93%; this high catalytic activity can be retained in full after three successive uses. The ensemble and electronic effect of Au–Pd nanoalloys were studied by IR spectroscopy using CO chemisorption, XPS and HRTEM. Moreover, the bifunctional nature of the acid–base MgAl-MMO support was found to be important as the acid sites are considered to be responsible for the improvement of catalytic activity; while, the basic sites gave rise to high selectivity. A possible mechanism with Au–Pd nanoparticles as the active sites has been proposed, illustrating that the oxidation of benzyl alcohol can proceed through the cooperation between the Au–Pd nanoalloys and the base/acid sites on the surface of the support.