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Constructing highly efficient electrocatalysts is vital to enhance oxygen evolution reaction (OER) performance at industrially relevant current densities. Herein, three-phase coupled Ni3S2/r-NiS/h-NiS composites are grown in situ on Ni foam (NNSN/NF) via a one-step solvothermal approach. The as-prepared composites need overpotentials of only 377 mV, 451 mV and 476 mV at 1000 mA cm−2 for the OER in alkaline freshwater, simulated seawater and seawater, respectively. In addition, the optimized catalyst exhibited long-term durability at 300 mA cm−2. Our work clarifies designing and preparing cost-effective Ni-based sulfide electrocatalysts for the OER in alkaline freshwater/simulated seawater/seawater under industrially relevant current densities. [ABSTRACT FROM AUTHOR]

Transition metal sulfides (TMSs) are considered as one of the promising electrode materials due to their fascinating redox reversibility and electronic conductivity. However, volume expansion during the charge/discharge process impedes their practical applications. The reasonable design of TMS electrode materials with unique morphology can improve the energy storage performance. Herein, we prepared the Ni3S2/Co9S8/NiS composite that is in situ grown on Ni foam (NF) via a one-step electrodeposition process. The optimized Ni3S2/Co9S8/NiS-7 shows a superhigh specific capacity of 2785.3 F g−1 at 1 A g−1 and remarkable rate capability. Furthermore, the as-assembled device displays a high energy density of 40.1 W h kg−1 at a power density of 799.3 W kg−1 and a satisfactory stability of 96.6% retention after 5000 cycles. This work provides a facile way to fabricate new TMS electrode materials for high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

Although the preparation of transition metal sulfides/oxides electrodes has been relatively perfected, it is still challenging to fabricate multi-component transition metal sulfides/oxides core–shell structure electrodes with excellent electrochemical performance. Herein, CoMoO4/MoO3@CuCoNi–S grown on nickel foam (NF) is first synthesized via facile hydrothermal and electrodeposition methods. The CoMoO4/MoO3@CuCoNi–S electrode presents an exceptional specific capacitance (2600.0 F g−1 at 1 A g−1) and 68.3% of its initial capacitance at 10 A g−1. Moreover, a CoMoO4/MoO3@CuCoNi–S//active carbon (AC) device is assembled for determining its electrochemical application. It reveals a high energy density of 42.1 W h kg−1 at a power density of 800.2 W kg−1, an extended voltage window of 1.6 V and excellent stability with 96.9% retention after 5000 cycles at 2 A g−1. This work offers a reference case for the development of multi-component transition metal sulfides/oxides core–shell structure composites for energy storage. [ABSTRACT FROM AUTHOR]

The exploitation of cost-efficiently electrocatalysts for hydrogen evolution reaction (HER) over a wide pH range remains a challenge. Herein, we prepared a novel multi-interface MoS2/Ni3S4/Mo2S3 composite on carbon cloth (CC) that acts as an efficient electrocatalyst over a wide pH range through a facile one-pot strategy, where (NH4)4[NiH6Mo6O24]·5H2O (abbreviated to NiMo6) as a bimetallic precursor and Ni(NO3)2·6H2O as one of the raw materials and salt are used together with thiourea (TU) for converting them into the MoS2/Ni3S4/Mo2S3 load on CC (abbreviated as MoS2/Ni3S4/Mo2S3/CC). MoS2/Ni3S4/Mo2S3/CC-24 h shows a distinguished electrocatalytic performance towards HER with long-term stability in acid and alkaline media. It presents low overpotentials of 38 mV and 51 mV in 0.5 M H2SO4 and 1.0 M KOH at 10 mA cm−2, respectively. This work can deliver a new idea to fabricate cost-efficient and long-term durability HER electrocatalysts over a broad pH range. [ABSTRACT FROM AUTHOR]

The electrochemical carbon dioxide reduction reaction (CO2RR) holds great promise for mitigating CO2 emission and simultaneously generating high energy fuel. However, it remains a great challenge to reduce CO2 to C2 products due to the lack of highly efficient catalysts. Herein, by means of a particle swarm optimization search and comprehensive density functional theory (DFT) computations, we predicted a hitherto unknown Cu2N monolayer with planar hexacoordinate Cu and tetracoordinate N atoms as a CO2RR catalyst. Our results revealed that the Cu2N monolayer shows outstanding stability and intrinsic metallicity. Interestingly, the as-designed Cu2N monolayer exhibits superior CO2RR catalytic performance with a rather low limiting potential (−0.33 V), resulting in the formation of a C2H4 product with a small kinetic barrier (0.55 eV) for the coupling between *CH2 and a CO molecule. Strikingly, the N atoms within the Cu2N monolayer were revealed to be the CO2RR active sites due to their significant binding strength with the CO2RR species and their significant spin moments. Our findings not only propose a useful roadmap for the discovery of 2D hypercoordinate materials, but also provide cost-effective opportunities for advancing sustainable CO2 conversion. [ABSTRACT FROM AUTHOR]

The electrochemical reduction of nitrobenzene to aniline (NBER) under ambient conditions is of great significance for sustainable industry and life. In this work, by means of density functional theory (DFT) computations, we have systematically investigated the potential of several (Ptn, n = 1–6 and 13) nanoclusters anchored on a holey C2N monolayer (Ptn/C2N) as NBER electrocatalysts. Our results revealed that Ptn/C2N materials exhibit high stability due to the strong interaction between the Pt-5d orbital and the N-2p orbital in C2N. Interestingly, among these Ptn/C2N catalysts, Pt3/C2N is the most active catalyst for NBER because of its rather small limiting potential (−0.19 V), in which the hydrogenation of Ph–NO2* to Ph–NOOH* is identified as the potential-determining step. Compared with other catalysts, the strongest binding strength of Ph–NOOH* on Pt3/C2N is responsible for its superior catalytic activity towards NBER. Our results provide a promising Pt cluster-based catalyst with high efficiency for NBER, which could open a new door for sustainable aniline production. [ABSTRACT FROM AUTHOR]

Abstract: The core-shell structured LaInO3:Ln3+@SiO2 (Ln3+ =Sm3+, Tb3+) phosphors were realized by coating LaInO3:Ln3+ phosphors on the surface of silica microspheres via a modified Pechini sol–gel process. The phase, structure, morphology, and fluorescent properties of the materials were well characterized by means of X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform IR spectroscopy (FT-IR), photoluminescence (PL) spectra, cathodoluminescence (CL) spectra, and the kinetic decays, respectively. The results reveal that the obtained core-shell structured phosphors consist of amorphous silica core and crystalline LaInO3:Ln3+ shell, which keep the uniform spherical morphology of pure silica spheres with narrow size distribution. Upon excitation by ultraviolet (UV) irradiation or electron beam, the phosphors show the characteristic emission lines of Sm3+ (4G5/2–6H5/2,7/2,9/2, orange) in LaInO3:Sm3+@SiO2 and characteristic emissions of Tb3+ (5D4–7F6,5,4,3, green) in LaInO3:Tb3+@SiO2, respectively. This kind of phosphors may have potential applications in field emission displays (FEDs) based on their uniform shape, low-cost synthetic route, and diverse luminescent properties. [ABSTRACT FROM AUTHOR]

Constructing highly efficient electrocatalysts is vital to enhance oxygen evolution reaction (OER) performance at industrially relevant current densities. Herein, three-phase coupled Ni 3 S 2 /r-NiS/h-NiS composites are grown in situ on Ni foam (NNSN/NF) via a one-step solvothermal approach. The as-prepared composites need overpotentials of only 377 mV, 451 mV and 476 mV at 1000 mA cm -2 for the OER in alkaline freshwater, simulated seawater and seawater, respectively. In addition, the optimized catalyst exhibited long-term durability at 300 mA cm -2 . Our work clarifies designing and preparing cost-effective Ni-based sulfide electrocatalysts for the OER in alkaline freshwater/simulated seawater/seawater under industrially relevant current densities.

Transition metal sulfides (TMSs) are considered as one of the promising electrode materials due to their fascinating redox reversibility and electronic conductivity. However, volume expansion during the charge/discharge process impedes their practical applications. The reasonable design of TMS electrode materials with unique morphology can improve the energy storage performance. Herein, we prepared the Ni 3 S 2 /Co 9 S 8 /NiS composite that is in situ grown on Ni foam (NF) via a one-step electrodeposition process. The optimized Ni 3 S 2 /Co 9 S 8 /NiS-7 shows a superhigh specific capacity of 2785.3 F g -1 at 1 A g -1 and remarkable rate capability. Furthermore, the as-assembled device displays a high energy density of 40.1 W h kg -1 at a power density of 799.3 W kg -1 and a satisfactory stability of 96.6% retention after 5000 cycles. This work provides a facile way to fabricate new TMS electrode materials for high-performance supercapacitors.

Although the preparation of transition metal sulfides/oxides electrodes has been relatively perfected, it is still challenging to fabricate multi-component transition metal sulfides/oxides core-shell structure electrodes with excellent electrochemical performance. Herein, CoMoO 4 /MoO 3 @CuCoNi-S grown on nickel foam (NF) is first synthesized via facile hydrothermal and electrodeposition methods. The CoMoO 4 /MoO 3 @CuCoNi-S electrode presents an exceptional specific capacitance (2600.0 F g -1 at 1 A g -1 ) and 68.3% of its initial capacitance at 10 A g -1 . Moreover, a CoMoO 4 /MoO 3 @CuCoNi-S//active carbon (AC) device is assembled for determining its electrochemical application. It reveals a high energy density of 42.1 W h kg -1 at a power density of 800.2 W kg -1 , an extended voltage window of 1.6 V and excellent stability with 96.9% retention after 5000 cycles at 2 A g -1 . This work offers a reference case for the development of multi-component transition metal sulfides/oxides core-shell structure composites for energy storage.

The exploitation of cost-efficiently electrocatalysts for hydrogen evolution reaction (HER) over a wide pH range remains a challenge. Herein, we prepared a novel multi-interface MoS 2 /Ni 3 S 4 /Mo 2 S 3 composite on carbon cloth (CC) that acts as an efficient electrocatalyst over a wide pH range through a facile one-pot strategy, where (NH 4 ) 4 [NiH 6 Mo 6 O 24 ]·5H 2 O (abbreviated to NiMo 6 ) as a bimetallic precursor and Ni(NO 3 ) 2 ·6H 2 O as one of the raw materials and salt are used together with thiourea (TU) for converting them into the MoS 2 /Ni 3 S 4 /Mo 2 S 3 load on CC (abbreviated as MoS 2 /Ni 3 S 4 /Mo 2 S 3 /CC). MoS 2 /Ni 3 S 4 /Mo 2 S 3 /CC-24 h shows a distinguished electrocatalytic performance towards HER with long-term stability in acid and alkaline media. It presents low overpotentials of 38 mV and 51 mV in 0.5 M H 2 SO 4 and 1.0 M KOH at 10 mA cm -2 , respectively. This work can deliver a new idea to fabricate cost-efficient and long-term durability HER electrocatalysts over a broad pH range.

The title compound, (C(3)H(5)N(2))(4)[As(6)CuMo(6)O(30)], is made up of a centrosymmetric anionic cluster and four imidazolium cations. In the cluster, the central Cu(II) atom is six-coordinated and lies on an inversion center. Adjacent clusters are linked via N-H⋯O hydrogen bonds between the imidazole cations and polyoxidoanions into a three-dimensional supra-molecular architecture.