Herein, the hydrothermal synthesis of porous ultrathin ternary NiFeV layer double hydroxides (LDHs) nanosheets grown on Nickel foam (NF) substrate as a highly efficient electrode toward overall water splitting in alkaline media is reported. The lateral size of the nanosheets is about a few hundreds of nanometers with the thickness of ≈10 nm. Among all molar ratios investigated, the Ni Fe V -LDHs/NF electrode depicts the optimized performance. It displays an excellent catalytic activity with a modest overpotential of 231 mV for the oxygen evolution reaction (OER) and 125 mV for the hydrogen evolution reaction (HER) in 1.0 m KOH electrolyte. Its exceptional activity is further shown in its small Tafel slope of 39.4 and 62.0 mV dec for OER and HER, respectively. More importantly, remarkable durability and stability are also observed. When used for overall water splitting, the Ni Fe V -LDHs/NF electrodes require a voltage of only 1.591 V to reach 10 mA cm in alkaline solution. These outstanding performances are mainly attributed to the synergistic effect of the ternary metal system that boosts the intrinsic catalytic activity and active surface area. This work explores a promising way to achieve the optimal inexpensive Ni-based hydroxide electrocatalyst for overall water splitting.

With the increasing emphasis on environmental protection, the development of flame retardants for epoxy resin (EP) has tended to be non-toxic, efficient, multifunctional and systematic. Currently reported flame retardants have been capable of providing flame retardancy, heat resistance and thermal stability to EP. However, many aspects still need to be further improved. This paper reviews the development of EPs in halogen-free flame retardants, focusing on phosphorus flame retardants, carbon-based materials, silicon flame retardants, inorganic nanofillers, and metal-containing compounds. These flame retardants can be used on their own or in combination to achieve the desired results. The effects of these flame retardants on the thermal stability and flame retardancy of EPs were discussed. Despite the great progress on flame retardants for EP in recent years, further improvement of EP is needed to obtain numerous eco-friendly high-performance materials.

Tin disulfide (SnS) has emerged as a promising anode material for lithium/sodium ion batteries (LIBs/SIBs) due to its unique layered structure, outstanding electrochemical properties and low cost. However, its poor cycling life and time-consuming synthesis as well as low-yield production hinder the practical utilization of nanostructured SnS. In this work, we demonstrate a simple and reliable dissolution-regeneration strategy to construct a flexible SnS/sulfur-doped reduced graphene oxide (S-rGO) composite as anodes for LIBs and SIBs, highlighting its mass-production feature. In addition, the robust affinity between SnS and S-rGO without interstitial volume is very beneficial for preventing the SnS particles from breaking themselves away from the rGO nanosheets into free nanoparticles. As a result, the SnS/S-rGO composite as anodes delivers high reversible capacities of 1078 mA h g and 564 mA h g (at 0.1 A g) for LIBs and SIBs, respectively, and excellent rate capabilities and cycling stability (e.g. 532 mA h g during the 600 cycles at 5.0 A g for LIBs). Our proposed strategy may also possess great potential for the practical application of other electrochemically active metal sulfide composites for energy devices.

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Recently, metal phosphides have been extensively investigated as promising anode materials for rechargeable batteries ascribing to their good electrical conductivities and favorable electrochemical performances. These materials usually exhibit conversion-type (and...

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Proton exchange membrane fuel cells (PEMFCs) have received considerable interest due to their low operating temperature and high energy conversion rate. However, their practical implement suffers from significant performance challenge. In particular, proton exchange membrane (PEM) as the core component of PEMFCs, have shown a strong correlation between its properties (e.g., proton conductivity, dimensional stability) and the performance of fuel cells. Metal-organic frameworks (MOFs) as porous inorganic-organic hybrid materials have attracted extensive attention in gas storage, gas separation and reaction catalysis. Recently, the MOFs-modified PEMs have shown outstanding performance, which have great merit in commercial application. This manuscript presents an overview of the recent progress in the modification of PEMs with MOFs, with a special focus on the modification mechanism of MOFs on the properties of composite membranes. The characteristics of different types of MOFs in modified application were summarized.