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Metal–organic framework (MOF)–derived materials have been extensively studied for water splitting applications; however, their direct utilization suffers from the limited activity. Herein, atom doping strategy is demonstrated to activate the electrocatalysis performance of nickel foam–supported Co-BDC (BDC: terephthalic acid) MOF by introducing Ir dopants. It is found that Ir doping induces benefits of modulated electronic structure, enhanced catalysis kinetics and charge transfer, and more catalysis sites for electrocatalysis. The prepared CoIr-BDC exhibits impressive activities for oxygen evolution in alkaline media (308 mV at a current density of 100 mA cm−2) and hydrogen evolution in all pH conditions (overpotentials of 90, 140, and 226 mV in acidic, alkaline, and neutral solutions at 100 mA cm−2). For overall electrolysis, the alkaline electrolyzer with CoIr-BDC as bifunctional catalysts delivers low voltage of 1.89 V at 400 mA cm−2. This study provides insight to boost the catalysis activity of MOF materials by incorporating metal atoms. [ABSTRACT FROM AUTHOR]

Multicomponent metal selenides with heterostructures are believed to effectively activate the surface pseudocapacitive contribution and improve the electrochemical dynamics, thus achieving high-performance anodes for sodium ion batteries (SIBs). Herein, a carbon coated CoSe2/Sb2Se3 heterojunction (CoSe2/Sb2Se3@C) is designed and constructed via an ion-exchange reaction between Co and Sb, and the subsequent selenization step. It is found that the hetero-structure and carbon shell effectively boost the charge transfer in the CoSe2/Sb2Se3@C composite electrode. The highly pseudocapacitive Na+ storage contribution is acquired due to the structural benefits of the heterojunction. Therefore, the CoSe2/Sb2Se3@C anode affords good cycling stability (264.5 mA h g−1 after 1000 cycles at 2 A g−1) and excellent rate capability (266.0 mA h g−1 at 5 A g−1). This study supplies a reference for developing an advanced anode with multicomponent and heterojunction structures for energy storage. [ABSTRACT FROM AUTHOR]

In this study, Fe1Pt3 nanoparticles are dispersed on MoS2 nanosheets to integrate the fascinating features of noble metal with highly exposed nanosheets. The MoS2 nanosheets supply good support for the uniform dispersion and easily accessibility of Fe1Pt3 nanoalloys, and ultrafine Fe1Pt3 nanoparticles provide a large number of active sites and enhanced catalysis/charge kinetics. The Fe1Pt3-MoS2 catalyst exhibits good hydrogen evolution performances in acidic media with low overpotential of 59 mV at current density of 10 mA cm−2 and robust catalysis kinetics (Tafel slope of 38 mV dec−1), making it high-efficiency HER catalyst with low Pt loading. [ABSTRACT FROM AUTHOR]

The application of metal oxides and sulfides for lithium‐ion batteries (LIBs) is hindered by the limited Li+ diffusion kinetics and inevitable structural damage. Pseudocapacitance for electrochemical lithium storage provides an effective and competitive solution for developing electrode materials with large capacity, high rate capability, and stability. Herein, a composite composed of VS4 nanoplates tightly bound to carbon nanotubes (VS4/CNTs) is developed to demonstrate pseudocapacitance‐assisted lithium storage. The texture of the assembled VS4 nanoplates supplies efficient electrolyte/ion diffusion, as well as exposed surface for pseudocapacitive behavior. The effective coupling between VS4 and CNTs ensures fast electron transfer and high stability. The VS4/CNTs anode exhibits high capacity of 1144 mAh g−1 at 0.1 A g−1, superior cycling stability (capacity retention of 100 % at 1 A g−1 after 400 cycles), and good rate capability. The pseudocapacitive behavior plays an important role in determining the excellent electrochemical properties, contributing to the increased charge rate and reaching as high as 42 % of the total charge at a scan rate of 1 mV s−1. This study demonstrates the potential application of metal sulfides with pseudocapacitive contribution in LIBs. [ABSTRACT FROM AUTHOR]

Pt-based bimetallic alloys have attracted intensive interests as highly efficient and stable heterogeneous catalysts for fuel cell applications, and searching flexible free-standing nanomembranes has been on the research focus because of their promising applications in catalysis, nanoelectronics, batteries, and sensing. Herein, a flexible free-standing paper composed of FePt alloy nanoparticles on nitrogen-doped paper (FePt-NG paper) has been developed as integrated electrode towards electrocatalytic oxidation of formic acid. It is found that, N doping is beneficial for the well dispersion of FePt nanoparticles on NG paper. The synergistic effect between Fe and Pt, as well as N doping effect simultaneously assures the improved catalytic activity of FePt-NG paper, making it the promising flexible electrode for application in fuel cell system. Moreover, the synthesis strategy could be used for the construction of other free-standing electrode towards catalysis, sensing, and battery applications. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Exploration of pH-universal and durable catalysts with specific structure and high performance is desirable but challenging for electrochemical water splitting. Aiming at this goal, hierarchical CoMoS3 nanotubes constructed of ultrathin nanosheet subunits are prepared via a self-sacrifice template method. The conversion from CoMoO4 nanorods to hierarchical MoCoS3 nanotubes is successfully realized through a facile solvothermal process. The obtained sample simultaneously possesses advanced structural superiority and synergism of ternary Co–Mo–S. Endowed with these advantages, MoCoS3 can serve as a pH-universal and high-performance electrocatalyst for hydrogen evolution, delivering low onset overpotential, small overpotential required to generate current density of 10 mA cm−2, and good stability. Moreover, it exhibits excellent catalytic performance in the electrochemical oxygen evolution reaction, making it a promising dual-functional catalyst for water electrolysis. [ABSTRACT FROM AUTHOR]

In developing flexible lithium-ion batteries (LIBs), fabrication of a high-performance electrode with good flexibility and stability is desirable, yet remains challenging. Herein, a flexible integrated electrode is introduced based on layer-by-layer packed graphene sheets entrapped SnO2–Co3O4 nanocubes. The rationally selected composition, polyhedral nanostructures, and proper construction of the specific architecture successfully trigger a synergistic lithium storage effect, assuring the partial reversible conversion of SnO2 and interfacial lithium storage of graphene, which are responsible for the remarkably high reversible capacity of 1665 mA h g−1 after 100 cycles at 100 mA g−1. Large and stable cyclic performance as well as long cyclic life is also obtained at a high current density of 1 A g−1 (1208 mA h g−1 after 1000 cycles). More importantly, the free-standing electrode can well retain its flexible feature even after 300 repeated electrochemical cycles, making it a promising candidate for a high-performance and stable electrode for flexible LIBs. [ABSTRACT FROM AUTHOR]

An improved method for mass production of good-quality graphene nanosheets (GNs) via ball milling pristine graphite with dry ice is presented. We also report the enhanced performance of these GNs as working electrode in lithium-ion batteries (LIBs). In this improved method, the decrease of necessary ball milling time from 48 to 24 h and the increase of Brunauer-Emmett-Teller surface area from 389.4 to 490 m/g might be resulted from the proper mixing of stainless steel balls with different diameters and the optimization of agitation speed. The as-prepared GNs are investigated in detail using a number of techniques, such as scanning electron microscope, atomic force microscope, high-resolution transmission electron microscopy, selected area electron diffraction, X-ray diffractometer, and Fourier transform infrared spectroscopic. To demonstrate the potential applications of these GNs, the performances of the LIBs with pure FeO electrode and FeO/graphene (FeO/G) composite electrode were carefully evaluated. Compared to FeO-LIBs, FeO/G-LIBs exhibited prominently enhanced performance and a reversible specific capacity of 900 mAh g after 5 cycles at 100 and 490 mAh g after 5 cycles at 800 mA g. The improved cyclic stability and enhanced rate capability were also obtained. [ABSTRACT FROM AUTHOR]

MoS2 has been nano-engineered with graphene quantum dots (GQDs) via a solvothermal treatment process to boost its electrochemical lithium storage properties. The doping with GQDs simultaneously endows MoS2 with structural and compositional advantages for high-performance lithium storage, including expanded interlayer distances between layers, fast electrochemical kinetics, and additional stability to buffer the volume variation. When evaluated as an anode material for lithium-ion batteries, GQDs/MoS2 delivers high capacity, improved cyclic performance and excellent rate capability. The composition dependent lithium storage performance has also been revealed for GQDs/MoS2. More importantly, the present nanoengineering could be used to boost the properties of other two-dimensional nanostructures for applications in energy storage and transit, catalysis, sensors and others. [ABSTRACT FROM AUTHOR]

Construction of nanostructured building blocks with specific composition, morphology, and internal architectures is an effective and promising strategy to improve the lithium storage of metal oxides. Herein, sandwiched graphene paper@Fe3O4 nanorod array@graphene (GPFG) composites are firstly designed and fabricated as integrated electrodes for high-performance lithium-ion batteries (LIBs). The Fe3O4 nanorod array, directly grown on the conductive graphene paper, assures fast reaction kinetics and high reversibility. The packing graphene not only accelerates the electron transfer but also buffers the volume strain. Therefore, the electrode delivers reasonably large and stable lithium storage, good rate capability, and an amazingly long cycling life of over 1450 cycles. [ABSTRACT FROM AUTHOR]

Exploration of high-rate lithium-ion batteries (LIBs) still remains a great challenge because of the ineffective charge transfer in electrode materials. In this work, the one-dimensional (1D)-2D coupled composites consisted of CoMoO nanorods and graphene sheets are developed as high-rate LIBs anode materials. The composites are well characterized with powder X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), thermogravimetric analysis (TGA), and Raman spectrum. Endowed with the structural advantages, the present sample exhibits remarkably enhanced electrochemical properties, such as the best high-rate performance for CoMoO-based electrode materials so far (646 mAh g at 5 A g after 200 cycles), excellent rate capability, and stable cyclability. [ABSTRACT FROM AUTHOR]

Coordination polymer (CP) templated synthesis of metal oxides has been researched intensively for applications in enhanced electrochemical energy storage and improved catalytic activity. In this manuscript, we demonstrate, for the first time, a topochemical transformation route to synthesize novel layered Co3O4 nanoplates using lamellar structured cobalt-based CPs as a template for optimized lithium-ion battery applications. Endowed with the synergistic advantages of 2D layered textural features and highly exposed reactive (111) crystal planes, the Co3O4 nanoplates exhibit remarkably enhanced lithium storage performance, including fast and high level lithium storage (852 mA h g−1 at 500 mA g−1 after 100 cycles), good rate capability (597 mA h g−1 at 1000 mA g−1 after 100 cycles) and stable cyclability (up to 200 cycles). [ABSTRACT FROM AUTHOR]

Three-dimensional CoO-graphene frameworks (3D-CGFs) are prepared with a one-pot hydrothermal method. CoO particles are in situ anchored on graphene sheets, and the resulting composite self-assembles into 3D architecture during the hydrothermal treatment. Scanning electron microscope, transmission electron microscope, powder X-ray powder diffraction, and Raman spectroscopy are employed to characterize the sample. When tested as anode materials for lithium-ion batteries, 3D-CGFs demonstrate remarkable electrochemical lithium storage properties, such as large and stable reversible capacity (>530 mAh g at 500 mA g over 300 cycles), good capacity retention (88 % retention after 300 cycles at 500 mA g compared with the 4th cycle), excellent high-rate performance (515 mAh g at 1 A g), making it a promising candidate for high-performance anode materials, especially for high-rate lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Mesoporous core–shell nanocomposites with porous α-Fe2O3 nanorods as the core and porous TiO2 as the shell are synthesized by calcination treatment of FeOOH@TiO2 core–shell nanorods. Due to the high capacity of Fe2O3 core and durable outer shell of TiO2, as well as the specific mesoporous nanostructures, the products deliver an excellent electrochemical performance towards lithium storage, including stable reversible capacity as high as ∼860 mA h g−1 at high current density of 1 A g−1, excellent cyclic stability with ultralong cycling life over 1000 cycles, and outstanding rate capability. The disclosure of the relationship between the components/structure and the lithium storage properties will greatly benefit the rational design and synthesis of high-performance nanocomposites for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

To pursue the novel magnetically recyclable photocatalyst, W has been successfully doped in FeO host matrix for the fabrication of FeWO nanoparticles through a one-pot hydrothermal progress with the addition of sodium dodecyl benzene sulfonate. The size range of the obtained nanoparticles is from 30 to 50 nm determined by SEM. And the particle size is about 41 nm calculated with Debye-Scherrer equation. X-ray diffraction analysis clearly shows that all peaks of FeWO nanoparticles shift slightly toward lower angles relative to those of the standard FeO, which resulted from the substitutions of Fe ions by the bigger W ions in the host lattice. When FeWO nanoparticles were applied to degrade methyl orange under the irradiation of a 10 W UV lamp, it showed a higher decomposition efficiency of 67 % than that of 55 % for normal TiO photocatalysts P-25. Moreover, FeWO nanoparticles can be conveniently and quickly recovered with a magnet and no decrease of photocatalytic activity has been observed after several consecutive rounds of photodegradation reaction. The magnetic FeWO nanoparticles with strong photocatalytic ability show promising applications in the degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

Nanoarray electrodes with highly capacitive materials and specific architectures are hopeful to realize advanced supercapacitor performance. The nickel foam (NF) supported hierarchical nanosheet array electrode is fabricated through a template route toward excellent capacitive supercapacitor. The hierarchical nanosheet array weaved with Ni(OH)2‐MnO2 nanowires provides multiple advantages for porous feature, high surface area, and fast charge transfer. The neighbored Ni(OH)2‐MnO2 supplies lattice fringes distortion as additional active sites as well as synergism, for improved capacitive performances. As expected, the Ni(OH)2‐MnO2/NF electrode manifests high specific capacitance of 14.7 F cm−2 at 2.5 mA cm−2 and good cyclic stability, making it hopeful for highly capacitive supercapacitor application. Hierarchical nanosheet array weaved by Ni(OH)2‐MnO2 nanowires is fabricated on nickel foam as integrated electrode for high‐capacity supercapacitor. The excellent performances are assigned to the structure benefits of hierarchical nanosheets, including high surface area, lattice fringes distortion, and shortened charge diffusion, as well as synergism between neighbored crystals hybridization. [ABSTRACT FROM AUTHOR]

Nanoarray electrodes with highly capacitive materials and specific architectures are hopeful to realize advanced supercapacitor performance. The nickel foam (NF) supported hierarchical nanosheet array electrode is fabricated through a template route toward excellent capacitive supercapacitor. The hierarchical nanosheet array weaved with Ni(OH)2‐MnO2 nanowires provides multiple advantages for porous feature, high surface area, and fast charge transfer. The neighbored Ni(OH)2‐MnO2 supplies lattice fringes distortion as additional active sites as well as synergism, for improved capacitive performances. As expected, the Ni(OH)2‐MnO2/NF electrode manifests high specific capacitance of 14.7 F cm−2 at 2.5 mA cm−2 and good cyclic stability, making it hopeful for highly capacitive supercapacitor application. Hierarchical nanosheet array weaved by Ni(OH)2‐MnO2 nanowires is fabricated on nickel foam as integrated electrode for high‐capacity supercapacitor. The excellent performances are assigned to the structure benefits of hierarchical nanosheets, including high surface area, lattice fringes distortion, and shortened charge diffusion, as well as synergism between neighbored crystals hybridization. [ABSTRACT FROM AUTHOR]

Correction for ‘Self-template synthesis of hierarchical CoMoS3 nanotubes constructed of ultrathin nanosheets for robust water electrolysis’ by Jinxue Guo et al., J. Mater. Chem. A, 2017, DOI: URL10.1039/c7ta02768k/URL. [ABSTRACT FROM AUTHOR]