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Abstract Oxygen evolution reaction (OER) contributes to the main overpotential during water splitting. Developing efficient, nonprecious OER electrocatalysts is vital for sustainable fuels. Herein, nickel iron boride nanosheets coupled with reduced graphene oxide (rGO) has been developed as efficient OER electrocatalyst. The two-dimensional hybrid affords high surface area and abundant active sites for catalytic reaction. The rGO substrate improves the charge transfer. The ternary Ni-Fe-B supplies synergism for OER. As a result, the Ni-Fe-B/rGO exhibits excellent OER performances with low overpotential of 265 mV at 10 mA cm−2, as well as excellent catalytic stability, making it the promising candidate for OER application. Graphical abstract Nickel iron boride nanosheets coupled with rGO has been firstly developed as efficient OER electrocatalyst, which delivers excellent OER activity that is superior to most of previously meal borides. fx1 Highlights • Ni-Fe-B nanosheets are closely coupled with rGO. • Structural advantages and rGO assure fast kinetics and large accessible sites. • Excellent OER catalytic activity and stability are obtained. [ABSTRACT FROM AUTHOR]

Porous frameworks with geometry nanostructures have attracted increasing research interest due to their specific architectures which offer structural advantages for energy conversion and storage. Here, we firstly report the synthesis of porous cubes constructed by hybrid SnO 2 -CoS nanoparticles using cubic CoSn(OH) 6 precursor as template. The porous nanostructures, nanosized subunits, as well as the cubic geometry feature offer abundant pores and channels for electrolyte diffusion, ensure large contact surface area between electrolytes and active materials, shorten transport distance of lithium ion, and supply voids to buffer the huge volume variation, making it an ideal candidate for reversible lithium storage. When used as anode material for lithium-ion batteries (LIBs), the developed sample exhibits outstanding electrochemical properties of large reversible capacity, high rate capability, and stable durability (750 mAh g −1 at 100 mA g −1 after 100 cycles). [ABSTRACT FROM AUTHOR]

To meet the increasing demands for sustainable hydrogen energy, molybdenum sulfide has gained considerable interest as non-precious electrocatalyst for hydrogen evolution reaction (HER) of water. However, effective nanoengineering technologies to boost its catalytic activity are still desirable but limited. Here, using advanced catalyst of N-doped graphene supported hybrid of MoS 2 nanosheets and Fe 4 [Fe(CN) 6 ] 3 (PB) nanocube, we demonstrate a novel solution for the enhancement of HER activity by simultaneously improving the catalytic site numbers and intrinsic unit activity on each catalytic site, as well as the electrical conductivity. In the hybrid catalyst, the proper selection of graphene and PB expedites the electron transfer and the synergistic effect of MoS 2 /graphene/PB influences the HER. Therefore, the present sample is an ideal catalyst towards HER and delivers impressively high catalytic activity, including the ultralow η 10 of 130 mV, superior durability, and large cathodic current density. We believe that this work contributes specific perspective to design and construction of advanced MoS 2 -based catalyst towards HER, and may inspire the development of other hybrid catalysts for sustainable energy conversion application. [ABSTRACT FROM AUTHOR]

Improving the electrochemical hydrogen evolution reaction (HER) activity of inexpensive catalysts is central in the area of sustainable energy conversion, yet remains an extraordinary challenge. Here, we firstly construct MoS 2 nanosheets vertically anchored on C 3 N 4 for high-efficiency electrochemical HER. The rational structure design endows MoS 2 nanosheets with combined advantages of maximally exposed edges and defect-rich structure. Moreover, the hybrid MoS 2 -C 3 N 4 possesses remarkably improved electrochemically active surface area and enhanced electrical conductivity than MoS 2 . Therefore, MoS 2 -C 3 N 4 exhibits robust electrocatalytic HER activity, including low overpotential (158 mV) required to generate the current density of 10 mA cm −2 , low Tafel slope (52 mV decade −1 ), and high current density (92 mA cm −2 at overpotential of 300 mV). [ABSTRACT FROM AUTHOR]

After years of development, boosting the electrochemical hydrogen evolution performance of MoS 2 catalyst through the traditional methods, such as defect engineering and conductivity improvement, has reached their limit. In this work, we propose a novel functional catalyst that is fabricated by hybrid two-dimensional nanostructures composed of MoS 2 nanosheets and CoMo 2 S 4 nanoplates in situ grown on graphene substrate for electrochemical hydrogen evolution reaction. The MoS 2 -CoMo 2 S 4 /graphene hybrid catalyst shows robust hydrogen evolution performance with low onset potential of 110 mV, high cathode current density of 85 mA cm −2 at η = 300 mV, and small Tafel slope of 42 mV dec −1 , as well as good durability. The excellent hydrogen evolution performance of the hybrid catalyst is likely attributed to the nonequilibrium composition, 2D structural advantages, conductive graphene substrate, and the electrocatalytic synergistic effect between MoS 2 and CoMo 2 S 4 . [ABSTRACT FROM AUTHOR]

Exploration of novel advanced materials for energy conversion and storage is on the research focus. Herein, we firstly develop FeMo 4 S 6 nanosheets via a hydrothermal process as advanced energy materials. TEM and XRD characterizations reveal that FeMo 4 S 6 nanosheets possess distinctive layered structure with an interlayer distance of 0.64 nm and 10–14 layers in thickness. Rooted in the intriguing layered 2D structural advantages and multicomponent effect, the sample exhibits large and stable lithium storage properties when it is used as anode material for lithium-ion batteries. It is also evaluated as electrocatalyst for water splitting and shows promising catalytic activity for hydrogen evolution, including low onset overpotential and stable cycling durability. [ABSTRACT FROM AUTHOR]

MoS 2 has emerged as an efficient hydrogen evolution catalyst and its activity is believed to be mainly determined by two factors: the amount of edge sites and electrical conductivity. To achieve improved catalytic activity, the few-layered oxygen-incorporated MoS 2 ultrathin nanosheets are prepared for the construction of hybrid nanosheets with graphene substrates using one-pot hydrothermal method for the first time. XRD, Raman, SEM, TEM, EDS and TGA techniques are used to characterize the hybrids. The moderate oxygen-incorporation into MoS 2 creates abundant edge sites and improves the conductivity. The tight coupling between the hybrid nanosheets expedites the electrical transfer. Endowed with the above advantages, the hybrid nanosheets are ideal electrocatalysts for hydrogen evolution reaction (HER) and exhibit high activity, which is demonstrated by the ultralow onset overpotential (120 mV), large cathodic current density (65.5 mA cm −2 at η = 300 mV), and small Tafel slope (51 mV decade −1 ), as well as superior cycling stability. Our enhanced understanding of this highly active MoS 2 hybrid catalyst for HER may facilitate the development of economical electrochemical hydrogen production systems. [ABSTRACT FROM AUTHOR]