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The metal corrosion possesses a serious threat to the safety and loss of property. The anticorrosion study on metal-organic frameworks (MOFs) remains rarely reported. Therefore, it is desirable to build MOFs-based anticorrosion coating with long-term corrosion resistance. Herein, we prepared a novel MOF-polymer anticorrosion composite PANI@MIL-101 by encapsulating polyaniline (PANI) within the pores of MIL-101 with in-situ polymerization of aniline monomer. The N 2 adsorption-desorption and transmission electron microscopy (TEM) of PANI@MIL-101 illustrate that PANI is successfully encapsulated in the pores of MIL-101 with in-situ polymerization. PANI@MIL-101 was dispersed in epoxy resin (EP) to prepare anti-corrosive coatings. The Tafel potentiodynamic polarization measurements and electrochemical impedance spectroscopy show that PANI@MIL-101/EP coating system has superior corrosion protection with the lowest i corr value and the highest |Z| 0.01 value compared with MIL-101/EP coating, PANI/EP coating and EP coating. A possible anticorrosion mechanism of PANI@MIL-101 was discussed. This work reveals that MOF-polymer composite materials are superb candidates for high-performance corrosion protection. [ABSTRACT FROM AUTHOR]

One-dimensional MoO2–Co2Mo3O8@C nanorods were synthesized by using MoO3@ZIF-67 composites as a precursor for the first time, and it is found that the Co2Mo3O8 species and its composite have excellent OER activities. The MoO2–Co2Mo3O8@C nanorods present favorable electrocatalytic advantages toward OER in alkaline solution, requiring an overpotential of only 320 mV to deliver a current density of 10 mA cm−2. In addition, the catalyst also shows a small Tafel slope of 88 mV dec−1 and relatively good durability. The attractive OER performance can be attributed to the highly active Co2Mo3O8 and MoO2 species and the unique structure of the catalyst. This strategy can be extended to design and synthesize other novel and highly efficient molybdenum based ternary metal oxides as OER catalysts. [ABSTRACT FROM AUTHOR]

The sluggish anodic oxygen evolution reaction (OER) greatly hinders the working efficiency of electrochemical water splitting to produce hydrogen, and it is therefore important to explore high-performance and cost-effective OER catalysts. In this communication, we report the synthesis of cobalt boride incorporated within porous carbon using a metal–organic framework (MOF) as a precursor. The high catalytic activity of Co–B and the high conductivity of carbon both contribute to the OER catalytic activity of Co–B/C. When used as an OER catalyst, this material shows high catalytic activity, delivering a current density of 10 mA cm − 2 at a low overpotential of 320 mV, as well as outstanding long-term electrochemical durability. This finding is of fundamental and practical importance as it not only extends the application of MOFs, but also introduces a new method for synthesizing highly efficient OER electrocatalysts. [ABSTRACT FROM AUTHOR]

Heteroatom doped porous carbons have been regarded as one of most promising candidates for Pt-free oxygen reduction reaction (ORR) catalysts. The proper heteroatom bonding configuration and synergistic effect of multiple atom co-doping are very important for improving their catalytic activity. In this work, a series of N, S co-doped porous carbons (NSCs) with excellent ORR performance were prepared by rationally using a dual-ligand metal organic framework as a carbon precursor. The interconnected porous structure, high surface area, N, S co-doping and high graphitization-N dopant, significantly contribute to the enhanced catalytic performance of ORR. The electrocatalyst studies indicated that the obtained materials have comparable ORR activity to that of the commercial Pt/C in both alkaline and acidic media, and superior long-term durability than that of Pt/C. This work can provide some guidance for synthesizing other multiple atom co-doping carbons for energy storage and conversion applications through target oriented synthesis of metal organic frameworks with different ligands. [ABSTRACT FROM AUTHOR]

• The size effect of Zn-MOF on the porosity and gas uptake of its derived carbon are investigated. • The large-size MOF tend to form porous carbons with higher specific surface area and large pore size. • The carbon derived from small-size MOF shows lower specific surface area and more micropores. • The CS-1000 shows a high CO 2 , H 2 and CH 4 uptake of uptake of 129.2, 241.6 cm3 g−1 and 58.3 cm3 g−1. Metal organic framework (MOF) derived carbon is an important kind of carbons with various potential applications. The structure of MOF precursor plays a key role in the proprieties of their derived carbon. Herein, the size effect of a Zn-MOF on the porosity and gas uptake of its derived carbon are investigated in detail. We found that the large-size MOF tend to form porous carbons with higher specific surface area as well as large pore size, while the carbon derived from small-size MOF shows lower specific surface area and more micropores as well as higher gas uptake. Especially, the CS-1000 derived from Zn-MOF-small shows a high CO 2 uptake of 129.2 cm3 g−1 at 273 K and 1 bar, a high H 2 uptake of 241.6 cm3 g−1 at 77 K and 1 bar, and a high CH 4 uptake of 58.3 cm3 g−1 at 273 K and 1 bar, making it very potential for carbon capture and sequestration and clean energy storage. [ABSTRACT FROM AUTHOR]

[Display omitted] • Single-atom Co catalysts with more Co-N 4 sites were successfully synthesized. • The catalyst exhibits an excellent ORR electrocatalytic activity. • The catalyst based Zn-air batteries shows higher peak power density. • DFT confirm that more Co-N 4 sites can lower the reaction energy barrier of ORR. Transition metal single atom catalysts (TM SACs) are the most promising oxygen reduction reaction (ORR) catalysts for proton exchange membrane fuel cells (PEMFCs) and metal-air batteries. However, the low density of M-N x active sites seriously hinders further improvement of the ORR electrocatalytic activity. Here, a strategy for encapsulating nitrogen-rich guest molecules (triethylenediamine cobalt complex, [Co(en) 3 ]3+) was proposed to construct a high-performance cobalt single-atom catalyst (Co-encapsulated SAC/NC). With this strategy, the guest molecules are encapsulated into metal–organic framework (MOF) cages as an additional cobalt source to boost cobalt loading, while abundant nitrogen from guest molecules contributes to the formation of Co-N 4 active sites. Remarkably, the resulting Co-encapsulated SAC/NC has a high cobalt loading amount of 4.03 wt%, and spherical aberration-corrected transmission electron microscopy (AC-TEM) has confirmed that most cobalt exists in a single-atom state. As a result, the Co-encapsulated SAC/NC exhibits excellent ORR catalytic performance with a half-wave potential of 0.88 V. Furthermore, Zn-air batteries employing Co-encapsulated SAC/NC as air cathode show high peak power density and excellent cycling stability. Density functional theory (DFT) calculations reveal that adjacent active sites have different rate-determining steps and lower reaction energy barriers than a single active site. [ABSTRACT FROM AUTHOR]

CoS 2 @MoS 2 @NiS 2 nano polyhedron with double-shelled structure was demonstrated to have multiple catalytic activity for HER, OER and ORR, which could serve as highly efficient catalysts for both rechargeable Zn-air batteries and overall water spitting. [Display omitted] • Double shelled hollow CoS 2 @MoS 2 @NiS 2 polyhedron was synthesized using a self-template method. • The CoS 2 @MoS 2 @NiS 2 exhibits multiple catalytic activity for HER, OER and ORR. • The CoS 2 @MoS 2 @NiS 2 exhibits a low HER overpotential of 156 mV at 10 mA cm−2. • The OER and ORR performance was demonstrated by rechargeable Zn-air battery. • The Zn-air battery can effectively drive water splitting device catalyzed by CoS 2 @MoS 2 @NiS 2. Electrocatalysts play important role in various energy conversion and storage devices. The catalytic performance of electrocatalysts can be enhanced through the increasement of intrinsic catalytic activity by optimizing electronic structure and the improvement of exposed active sites by designing proper nanostructures. In this work, CoS 2 @MoS 2 @NiS 2 nano polyhedron with double-shelled structure was prepared using metal organic framework as a precursor. Due to the rational integration of multifunctional active center, the strong electronic interaction of the various component, the high electrochemical surface area and shortened mass transport induced by the special structure, CoS 2 @MoS 2 @NiS 2 exhibits high catalytic activity for hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). Specifically, low overpotentials of 156 and 200 mV was achieved to deliver a current density of 10 mA cm−2 for HER and OER, and a high half-wave potential of 0.80 V was observed for ORR. More importantly, the Zn-air battery assembled by CoS 2 @MoS 2 @NiS 2 exhibits a high-power density of 80.28 mW cm−2 and could effectively drive overall water splitting. This work provides a new platform for designing multifunctional catalysts with high activity for energy conversion and storage. [ABSTRACT FROM AUTHOR]

• Synthesis of ZnG@ZIF-8 composite using the ZnG as a single metal source. • The ZnG@ZIF-8 composite enhanced sustainability of the inhibitors. • The ZnG@ZIF-8/EP coatings displayed excellent corrosion resistance. The unique porous characteristic of metal-organic frameworks (MOFs) has been attracting significant attention for gas storage, catalysis and drug delivery. However, the studies regarding loading inhibitors into MOFs for metallic anti-corrosion applications are scarcely reported. Herein, a strategy based on encapsulating corrosion inhibitors into MOFs matrix has been developed, and their corrosion process and mechanism have been fully studied. Specifically, an environmentally friendly green corrosion inhibitor, zinc gluconate (ZnG), was selected as a metal resource for the preparation of ZIF-8 and then inherently intercalated into the porous ZIF-8. Various characterizations were carried out to confirm that zinc gluconate was successfully loaded into the ZIF-8 matrix. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization curves show the evidence that the prepared ZnG@ZIF-8/EP coatings display good metallic anti-corrosion performances. The probably protecting mechanism of ZnG@ZIF/EP coatings for magnesium alloy surface was thoroughly discussed. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen evolution is an efficient strategy to convert solar energy into hydrogen energy, which is of significant importance to solve the issues of energies shortage and environmental pollution. Transition metal sulfides have been widely investigated owing to their high catalytic activity, appropriate band gap, and wide range of photo responsive capacity and low cost. At the same time, benefiting from their adjustable structure, high specific surface area and diverse metal centers, metal-organic frameworks (MOFs) are promising precursors to prepare transition metal sulfides. In this paper, recent progress of transition metal sulfide photocatalytic materials derived from MOFs for hydrogen evolution are summarized. The effects of metal centers, nanostructure and band gap of the metal sulfides on their photocatalytic hydrogen evolution efficiency are discussed and the proposed reaction mechanisms are summarized. In addition, the challenges and development direction in this area are proposed to provide new guidance for the progress of MOFs-derived metal sulfides photocatalysts. [Display omitted] • The progress of transition metal sulfide derived from MOFs for photocatalytic hydrogen evolution are summarized. • The effects of metal centers, nanostructure and band gap on their photocatalytic hydrogen evolution efficiency are discussed. • The photocatalytic reaction mechanisms are summarized. • The challenges and development direction in this area are proposed. [ABSTRACT FROM AUTHOR]

Abstract: Most of single‐component white‐light‐emitting materials focus on organic–inorganic hybrid perovskites, metal–organic frameworks, as well as all‐inorganic semiconductors. In this work, we successfully assembled an all‐inorganic layered perovskite by mixing two halogens of distinct ionic radii, namely, Rb2CdCl2I2, which emits “warm” white light with a high color rendering index of 88. To date, Rb2CdCl2I2 is the first single‐component white‐light‐emitting material with an all‐inorganic layered perovskite structure. Furthermore, Rb2CdCl2I2 is thermally highly stable up to 575 K. A series of luminescence measurements show that the white‐light emission arises from the lattice deformation, which are closely related to the [CdCl4I2]2− octahedra with high distortion from the distinct ionic radii of Cl and I. The first‐principles calculations reveal that both the Cl and I components make significant contributions to the electronic band structures of Rb2CdCl2I2. These findings indicate that mixing halogens is an effective route to design and synthesize new single‐component white‐light‐emitting materials. [ABSTRACT FROM AUTHOR]