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The development of a new catalyst for the low-cost, environmentally friendly and highly efficient oxygen reduction reaction (ORR) is important for the commercialization of fuel cells. Herein, a smart strategy was proposed for the preparation of a novel nitrogen-doped nanoporous carbon (N-PC) using resource-rich pomelo peel, a type of waste, as starting material. The typical product (N-PC-1000) possesses a high BET surface area (up to 1444.9 m2 g−1), porous structure and high graphitic N content. In alkaline and acidic media, the N-PC-1000 shows not only decent catalytic activities in terms of onset potential and current density, but also has excellent tolerance to methanol poisoning effects and durability. This study provides worthy inspiration for using other environmental wastes to prepare related functional carbon materials with a variety of promising practical applications such as supercapacitors and lithium-ion batteries.

In this work, we developed the freeze-drying method with thermal annealing in nitrogen atmosphere to prepare a hybrid containing molybdenum dioxide (MoO2) and reduced graphene oxide (RGO) from ammonium molybdate (NH4)6Mo7O24·4H2O and graphene oxide (GO). As a result, MoO2 nanoplates were uniformly anchored on RGO matrix, and when used as an anode material for lithium ion batteries, the hybrid delivered excellent electrochemical properties including high rate capability and stable cycle performance, the reversible capacity remained at ~800 mA h g−1 after 120 cycles at a current density of 100 mA g−1. The high capacity over prolonged cycling achieved could be attributed to the formation of two-dimensional electrical percolating networks, homogeneous dispersion and immobilization of MoO2 nanoparticles.

With the ability of large specific capacities and long cycle life, hybrid materials containing iron oxides are extensively investigated as anode materials for lithium-ion batteries (LIBs). In this work, Fe2O3/ZnO mesoporous bi-components were prepared by using solvothermal MOFs templating method and then an annealing process. When used as an anode material for lithium-ion batteries, thus-obtained composite showed excellent electrochemical performance, including good charge and discharge specific capacity, excellent rate capacity and a relatively stable cycle performance (ca. 700 mA h g−1 at a current density of 100 mA g−1 after 60 cycles). This novel method for the synthesis of functional hybrid materials can be open up the preparation of various MOFs-derived functional nanocomposites in lithium-ion batteries.

A Co3O4/N-doped reduced graphene oxide (N-doped GN) nanocomposite was successfully synthesized by a facile freeze-drying method and heat-treated subsequently. When used as an anode material for lithium ion batteries (LIBs), the composite showed superb cycling stability and rate performance. More remarkably, the Co3O4/N-doped GN composite achieved an ultrahigh reversible capacity of 950 mA h g−1 exceeds the theoretical capacity (890 mA h g−1) of Co3O4 after 100 cycles at a current density of 0.2 A g−1, which made it a promising anode material for LIBs. Therefore, the nanocomposite can be deemed to be potential candidates as anode materials for further investigation.

•The Fe3O4/Cu2O/Ag composite was first successfully synthesized via a facile method.•The ternary composite shows unexpected photocatalytic activity.•The (111) facet of Cu2O was found be higher activity facet.•The photocatalyst can be easily recycled by a magnet.In this work, a novel magnetic and ordered Fe3O4/Cu2O/Ag ternary composite was successfully synthesized via one-pot method in the presence of Fe3O4 nanoparticles. The glycol-ethanol mixed system was used as both solvent and reductant for the simultaneous formation of Cu2O and Ag. The porous and hollow flower-like Fe3O4/Cu2O/Ag composite was self-assembled by many nanosheets with an average thickness of 10 nm and exhibited unexpected photocatalytic activity for the degradation of methyl orange (MO) under visible light. The degradation rate of MO in aqueous solution (1×10−4 mol L−1) reached to 97.7% within 40 min. The (111) facet of Cu2O exhibited higher activity for the absorption of MO. Furthermore, ternary composite could be easily recycled by applying an external magnetic field without significant decrease of the catalytic activity even after running 5 times, which presented higher stability and efficiency than Fe3O4@Cu2O. This work would provide a new sight for the construction of visible light-responsive photocatalysts with high performance.Photocatalytic Mechanism Scheme of the Fe3O4/Cu2O/Ag composite under visible light irradiation. Such a remarkable photocatalytic activity of composite is related to the surface plasmon resonance effect of Ag nanoparticles and the powerful absorption ability of the (111) facets of Cu2O to MO.

In this study, novel core–shell crosslinked dextran–hemin micelles were first successfully synthesized. Hemin grafted to dextran is not only used as a phototriggered switch for the controlled release of loaded 5-fluorouracil (5FU) quickly, but also simultaneously as a photosensitizer for photodynamic therapy under laser irradiation. The prepared micelles exhibit high stability against extensive dilution of solution which can restrain premature drug loss and reduce side effects to human bodies. The micelles possess good biocompatibility as well. More importantly, 5FU-loaded crosslinked dextran–hemin micelles present greater antitumor effect than free 5FU or crosslinked micelles under laser irradiation, indicating the excellent synergetic antitumor effect of hemin with 5FU in the as-prepared micelles. We are convinced that these phototriggered crosslinked micelles combining chemotherapy and photodynamic therapy have tremendous potential for localized cancer treatment.

In this study, novel core–shell crosslinked dextran–hemin micelles were first successfully synthesized. Hemin grafted to dextran is not only used as a phototriggered switch for the controlled release of loaded 5-fluorouracil (5FU) quickly, but also simultaneously as a photosensitizer for photodynamic therapy under laser irradiation. The prepared micelles exhibit high stability against extensive dilution of solution which can restrain premature drug loss and reduce side effects to human bodies. The micelles possess good biocompatibility as well. More importantly, 5FU-loaded crosslinked dextran–hemin micelles present greater antitumor effect than free 5FU or crosslinked micelles under laser irradiation, indicating the excellent synergetic antitumor effect of hemin with 5FU in the as-prepared micelles. We are convinced that these phototriggered crosslinked micelles combining chemotherapy and photodynamic therapy have tremendous potential for localized cancer treatment.