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Abstract Oxygen evolution reaction (OER) plays a key role in electrochemical splitting of water and it is urgent to develop high-performance and cost-effective OER catalysts. In this work, we report the synthesis of V-Co/CoO@C nanorod as highly efficient OER catalysts. The V 2 O 5 nanowire and metal organic framework composite leads to the successful preparation of the catalyst. The V 2 O 5 nanowire not only induces the formation of Co/CoO species, but also facilitates uniform V doping. When used as OER catalyst, the V-Co/CoO@C nanorod only needs a low overpotential of 320 mV to achieve a high current density of 10 mA·cm−2. Graphical abstract Unlabelled Image Highlights • Porous V-Co/CoO@C nanorod was synthesized by using a V 2 O 5 @ZIF-67 as precursor. • The V-Co/CoO@C nanorod shows high OER activity of 10 mA·cm−2 at a η value of 320 mV. • The use of V 2 O 5 lead to the formation of Co/CoO and V doping. • The Co/CoO species and uniform V doping contributed to its OER performance. [ABSTRACT FROM AUTHOR]

Abstract The oxygen reduction reaction (ORR) is one of the core reactions that occur in fuel cells and metal air batteries. Metal-free catalysts such as porous carbons are promising candidates for ORR and the performance of porous carbons strongly depends on their nanostructure. Herein, we reported the synthesis of high surface area N doped carbon nanotube (CNT-900) by using ZnO@zeolite imidazolate framework (ZnO@ZIF-8) nanowire as a precursor. When used for an ORR catalyst, the CNT-900 show obvious superior performance compared with the carbon derived from ZIF-8. In addition, it exhibits comparable activity with 20 wt% Pt/C and superior stability. Combined with green and facile synthesis strategy, the method in this work can be easily extended to synthesis other nanomaterials for energy storage and conversion application. Graphical abstract N doped carbon nanotube with high surface area and ORR performance was synthesized by using ZnO@ZIF-8 nanowire as precursor. Unlabelled Image Highlights • ZnO@ZIF-8 was facilely synthesized at room temperature and converted to N doped carbon nanotube at 900 °C. • The CNT-900 shows very high surface area, which greatly improves its ORR performance. • The CNT-900 exhibits comparable activity with 20 wt% Pt/C and superior stability. [ABSTRACT FROM AUTHOR]

Pt-based alloys have been explored as the most promising cathode catalyst for fuel cells due to their excellent electrocatalytic activity in oxygen reduction reaction (ORR). However, the long-term performance of Pt-based alloys is compromised owing to the de-alloying behavior under the corrosive circumstance. More importantly, the complicated synthesized methods have hindered their further practical application. In this report, a facile and effective operating conditions-assisted method has been developed to synthesize the stable hexagonal nanoplates PtFe alloy with a high electrocatalytic activity. In the three prepared PtM (M: Fe, Co, Ni) alloy samples, the PtFe alloy exhibits a superior catalytic activity, which improves by about 100 and 178 mV for half-wave potential in alkaline and acidic medium with the same Pt-loading amount, respectively. In addition, the PtFe alloy catalyst exhibits an electrochemical stability, compared to the conventional carbon-supported Pt catalysts. In view of the advantages of the facile operating preparation and the excellent electrocatalytic performance, we believe that the hexagonal nanoplates PtFe alloy holds great application as a promising electrocatalyst in polymer electrolyte membrane fuel cell (PEMFC). [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]

• MoO 2 @MoS 2 @Co 9 S 8 heterostructure nanorod by utilizing MoO 3 @ZIF-67 as a precursor. • The nanorod is assembled by 2D nanosheet with high electrochemical surface area. • The nanorod can serve as bifunctional electrocatalyst for overall water splitting. • The HER and OER overpotentials at 10 mA cm−2 are 160 mV and 310 mV. • The high performance is induced by the synergistic effect of the heterostructure. Developing low-cost and high-efficiency bifunctional catalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) to catalyze electrochemical overall water splitting is critical for the production of hydrogen. Herein, we develop an in-situ reduction and vulcanization strategy to prepare MoO 2 @MoS 2 @Co 9 S 8 heterostructure nanorods by utilizing MoO 3 @ZIF-67 as a precursor. The reduction of MoO 3 can produce more conductive MoO 2 , and the vulcanization reaction can produce highly active MoS 2 for the HER as well as highly active Co 9 S 8 for the OER. In addition, the MoS 2 anchor on the MoO 2 not only facilitates electron transfer, but also interacts with Co 9 S 8 to induce a synergic catalytic effect by the electron transfer between them. Moreover, the 2D nanosheet assembled heterostructure nanorods can provide a large electrochemical surface area. Therefore, the merits of the materials are fully utilized and outstanding catalytic performances are achieved. MoO 2 @MoS 2 @Co 9 S 8 can catalyze HER and OER effectively with overpotentials of 160 and 310 mV at 10 mA cm−2, indicating its bifunctional activity. In addition, the two electrode electrolyzer catalyzed by MoO 2 @MoS 2 @Co 9 S 8 can reach 10 mA cm−2 current density at a cell voltage of 1.62 V with very high stability, demonstrating its practical application for water splitting. [ABSTRACT FROM AUTHOR]

A new acentric sulfate, Cs 2 Zn 2 (SO 4) 3 , has a two-dimensional layered structure, which is different from A 2 B 2 (SO 4) 3 (A = K, Rb, B = Mg, Ca, Cd, Zn) type that owns three-dimensional framework. Meanwhile, Cs 2 Zn 2 (SO 4) 3 exhibits a moderate second-order NLO response of about 0.15 × KH 2 PO 4. This work will enrich the diversity of sulfate structure and provide new desgin strategy on the synthesis of novel NLO sulfates. • A new congruently melting sulfate Cs 2 Zn 2 (SO 4) 3 is synthesized. • Cs 2 Zn 2 (SO 4) 3 exhibits a unique two-dimensional layer structure. • Cs 2 Zn 2 (SO 4) 3 exhibits second-order nonlinear optical response of about 0.15 × KH 2 PO 4. Acentric structure is the indispensable condition for a compund to exhibit nonlinear optical (NLO) response. However, it's difficult for inorganic sulfates to crystallize in acentric structures. In this communication, a new acentric sulfate, Cs 2 Zn 2 (SO 4) 3 , has been synthesized by spontaneous crystallization method. The crystal structure of Cs 2 Zn 2 (SO 4) 3 is layered and is composed of Zn 2 (SO 4) 3 layers and Cs+ cations, which is different from A 2 B 2 (SO 4) 3 (A = K, Rb, B = Mg, Ca, Cd, Zn) type that owns three-dimensional framework. Powder NLO response suggest that Cs 2 Zn 2 (SO 4) 3 exhibits a moderate second-order NLO response of about 0.15 × KH 2 PO 4. Theoretical calculations were performed and elucidated that the origination of NLO response is from SO 4 groups and ZnO n (n = 4, 5) polyhedra. This work will enrich the diversity of sulfate structure and provide new desgin strategy on the synthesis of novel NLO sulfates. [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]

• ZnS decorated N, S co-doped porous carbon polyhedron are synthesized. • A small fraction of ZnS can greatly improve the ORR activity of the catalyst. • The ZnS@NC-3 shows comparable ORR activity with 20 wt% Pt/C catalyst. • The Zn-air battery using ZnS@NC-3 shows an open circuit voltage of 1.524 V. • The Zn-air battery exhibit a power density of 176 mW cm−2 and a specific capacity of 736 mA h g−1. Developing low cost, environmentally friendly and high efficiency oxygen reduction reaction (ORR) electrocatalysts is critical for clean energy conversion and storage devices including fuel cells and metal-air batteries. Herein, we developed a facile method to doping N, S and ZnS into carbon framework simultaneously. The N, S co-doping and extra ZnS active sites could prominently enhance the ORR performance of the carbon. The optimized sample ZnS@NC-3 exhibit an onset potential of 0.94 V and a half-wave potential of 0.84 V, which is comparable to 20 wt% Pt/C. In addition, the methanol tolerance and cycle ability are obvious superior than that of Pt/C. Moreover, when used as electrocatalysts for Zn-air battery, the battery exhibits an open circuit voltage of 1.524 V, a high specific capacity of 736 mA h g−1 and a max power density of 176 mW cm−2, demonstrating its great potential for clean energy conversion. [ABSTRACT FROM AUTHOR]

Designing efficient oxygen evolution reaction (OER) electrocatalysts is crucial for practical applications in water splitting and metal-air battery devices. Special structures of materials often bring in unprecedented catalytic activity. Herein, we first report the synthesis of CoMoO 4 nanotube by using MoO 3 @ZIF-67 nanorod. The CoMoO 4 nanotube shows high OER activity with a low overpotential of 315 mV delivering a current density of 10 mA cm−2. The electro-catalytic activity surpasses that of many Co and Mo-based catalysts. Furthermore, the strategy presented here is facile, and can be extended to the synthesis of other Mo-based nanotube materials for energy storage and conversion. Unlabelled Image • CoMoO 4 nanotube was prepared by using MOF composite as precursor for the first time. • The CoMoO 4 shows high a specific surface area of 157 m2 g−1. • The CoMoO 4 shows high OER activity of 10 mA cm−2 at an overpotential of 315 mV. • The CoMoO 4 also shows outstanding long-term electrochemical durability. [ABSTRACT FROM AUTHOR]

The competitive phase selection during cooling a metastable alloy is mainly controlled by the process of nucleation and growth for either the equilibrium stable phase or metastable phase. However, the control of competitive phase selection is still a standing challenge. In this work, a general method for controlling the competitive phase selection process by in-situ forming nanoparticles is reported. The solidification experiments of Cu-Cr metastable immiscible alloys were performed to probe the effect of in-situ TiB 2 , Cr 3 C 2 /Cr 7 C 3 or TiC nanoparticles. The results indicate that the Cr-rich minority phase originates from the liquid-solid phase transformation and exhibits coarse dendrite morphology for the Cu-Cr alloy without nanoparticles. In contrast, suitable nanoparticles may lower the Gibbs free energy barrier for the formation of metastable phase, trigger the liquid-liquid phase transformation, thus the Cr-rich minority phase almost shows spherical morphology and the size is only a few microns, even hundreds of nanometers. Furthermore, the microhardness of Cu-Cr alloys with nanoparticles is improved significantly. This strategy may have extensive application prospects for the modification of phase selection behaviors and solidification process of Cu-Cr metastable immiscible alloy. [Display omitted] • A general method for controlling the competitive phase selection process by in-situ nanoparticles is proposed. • Suitable nanoparticles lower the Gibbs free energy barrier and the undercooling for the formation of metastable phase. • in-situ TiB 2 , Cr 3 C 2 , Cr 7 C 3 or TiC nanoparticles can modify the phase selection behaviors of Cu-Cr alloys. [ABSTRACT FROM AUTHOR]

Ir nanoparticles have been synthesized by using a sample hydrothermal method while well dispersed Ir@SiO 2 composite microspheres could be obtained hydrothermally after adding SiO 2 microspheres into the synthesis system. Particles of Ir formed on the surface of SiO 2 microspheres were well crystalline similar to the pure Ir nanoparticles. Both the glassy carbon electrodes modified by Ir nanoparticles and Ir@SiO 2 composite microspheres showed weak electrochemical activities toward oxidation of dopamine and ascorbic acid. However, the Ir nanoparticles modified gold electrode displayed an obvious catalytic activity toward electrooxidation of either dopamine or ascorbic acid. For the gold electrode modified with Ir@SiO 2 composite microspheres, the electrochemical behavior could be affected obviously by the quantity of the electrocatalyst on the surface of bare gold electrode. The relationship between structure and property of both samples have been studied and analyzed based on the experimental data. [ABSTRACT FROM AUTHOR]

• Preparation of pure inorganic piezoelectric nanofiber membrane at low temperature. • By lowering the temperature, the pure inorganic piezoelectric fiber membrane shows good flexibility. • It is found that ultrasonic vibration can accelerate the adsorption behavior of fiber membrane. • Through the color change after PZT saturated adsorption, the actual concentration of the dye can be quickly determined. It is a challenge to achieve flexibility in purely inorganic piezoelectric materials without organic support, and various thin film flexible inorganic piezoelectric materials has been developed recently. In this work, lead zirconate titanate (PZT) nanofiber membranes were prepared by electrospinning, and a flexible membranes can be obtained by reducing the calcination temperature, and the flexibility was characterized by the three-point method. The fiber membrane was relatively thicker in relative to thin films and confirmed to adsorb Congo Red quickly under the action of ultrasound. The maximum adsorption capacity is 61.78 mg g−1 and saturation time reaches 20 min under ultrasound treatment. In addition, the color change after saturation adsorption can quickly determine the actual load of the fiber membrane. In the future, this load saturation effect can be used to calibrate the relationship between the piezoelectric signal and the adsorption load, so as to obtain more accurate chemical sensors. [ABSTRACT FROM AUTHOR]

Chronic morphine tolerance is a repulsive barrier to the clinical treatment of pain. Whereas the underlying molecular mechanisms of morphine tolerance remain unknown. Here, we proposed that tumor necrosis factor-α-induced protein 8-like 2 (TIPE2) is an essential control point regarding the progression of chronic morphine antinociceptive tolerance. We found that TIPE2 levels in the lumbar spinal cord were significantly downregulated in the morphine tolerance mouse model. Specifically, decreased TIPE2 by morphine tolerance was primarily expressed in spinal neurons, while increased expression of spinal TIPE2 distinctly attenuated the chronic morphine antinociceptive tolerance and tolerance-associated hyperalgesia. We also observed that increased expression of spinal TIPE2 significantly reduced morphine tolerance-induced neuronal ROS production and apoptosis, along with the activation of MAPKs and NF-κB signaling pathways. Moreover, the increased TIPE2 expression inhibited neuronal activation and glial reactivity in the spinal dorsal horn after chronic morphine exposure. Additionally, TIPE2 overexpression in cultured SH-SY5Y cells significantly suppressed ROS production and apoptosis in response to morphine challenge. Therefore, we can conclude that the upregulation of spinal TIPE2 may attenuate the morphine antinociceptive tolerance via TIPE2-dependent downregulation of neuronal ROS, inhibition of neuronal apoptosis, suppression of MAPKs and NF-κB activation. TIPE2 may be a potential strategy for preventing morphine tolerance in the future studies and clinical settings. [Display omitted] • Tumor necrosis factor-α-induced protein 8-like 2 is downregulated during induction of morphine antinociceptive tolerance. • Tumor necrosis factor-α-induced protein 8-like 2 is an important negative regulator in morphine antinociceptive tolerance and tolerance-induced hyperalgesia. • Tumor necrosis factor-α-induced protein 8-like 2 reduces morphine-induced ROS accumulation and apoptosis in neurons. • Tumor necrosis factor-α-induced protein 8-like 2 may inhibit MAPKs and NF-κB activation to alleviate morphine antinociceptive tolerance. [ABSTRACT FROM AUTHOR]

• Application of an innovative combination model for the pyrolysis of OS is proposed. • The high heating rate is beneficial for the pyrolysis of OS. • A three-step thermal decomposition model is proposed to describe pyrolysis process. • Results will be useful for optimization of OS industrial pyrolysis and treatment. Oil sludge (OS) is one of the main waste in the petrochemical industry, and serious consequences can result from the improper disposal of this waste. Pyrolysis is an effective method to dispose of OS and to recover the high heating value combustibles from it. The pyrolysis of three OS samples was carried out in a nitrogen atmosphere at heating rates of 5 °C/min, 10 °C/min, and 20 °C/min, respectively. The TG-DTG/DSC-DDSC curves show that the thermal decomposition of OS has been divided into 5 stages, and each stage has unique thermal decomposition characteristics. Two model-free methods were used to calculate the apparent activation energy at a conversion rate from 0.05 to 0.95, and based on 10 solid-state mechanisms of thermal decomposition, the model-based method was used to fit the thermal decomposition mechanisms exposed to the three heating rates. The results show that the high heating rate is beneficial for the pyrolysis of OS. The apparent activation energy varies irregularly with the conversion rate, and the apparent activation energy error calculated by the FWO method is smaller. For the three samples, OS-1, OS-2 and OS-3, the average apparent activation energies calculated by the FWO method are 40.39 kJ/mol, 38.01 kJ/mol, and 85.53 kJ/mol, respectively. The mechanism function of OS thermal decomposition changed, and the process of thermal decomposition should be described by a three-step thermal decomposition model. During 140.48–331.88 °C, the fitting correlation coefficients of the two-dimensional phase interfacial reaction mechanism under the three heating rates were all above 0.99. During 400.00–556.57 °C, the fitting result of the three-dimensional nucleation and growth mechanism is better than fitting results of other models. During 583.82–676.60 °C, the two-dimensional diffusion mechanism has a good fitting regression. Significantly, model-based method and model-free method provide effective and reliable thermal decomposition kinetics parameters and models as a theoretical support for optimization of OS industrial pyrolysis and treatment of OS. [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]

Understanding the spatial and temporal characterization of soil properties, along with soil management practices, helps in analyzing soil properties changes and timely adjusting management patterns. Moreover, soil fertility evaluation within farmland is urgently needed for understanding soil fertility level and avoiding soil degradation. This study addressed the spatial and temporal changes of both soil properties and soil fertility, and their causes in a large grain-production area of China's subtropical plain, which has been used as the national commodity grain base for 35 years. In 2007 and 2017, 827 and 733 soil samples were collected across the area, respectively. Soil pH, organic matter (OM), available nitrogen (AN), available phosphorus (AP) and available potassium (AK) were measured. The changes of soil properties were analyzed with the descriptive statistics methods and geostatistical methods, while the soil integrated fertility index (IFI) was calculated by the integrated fertility index method combined with the minimum data set method. In general, 2017 had a lower variability than 2007 for all properties except AP, and pH had a lower variability than other indicators. Differences of all indexes among 6 cropping systems and 2 crop years were significant, and oilseed rape-soybean cropping system performed better than other cropping systems in most indexes. Moreover, in 2007 there was a stronger spatial dependence than in 2017, and AP and OM had a stronger spatial dependence than other indicators. Mapping indicated that a more patchy distribution of all indicators was found in 2007 than in 2017. In addition, OM and AK in soil decreased substantially, and AN decreased slightly, but AP and pH increased. By principal component analysis and correlation analysis selected OM, AP and AK as soil IFI evaluation indexes, and their weights were determined. The IFI results showed that soil fertility declined in all areas, while the double rotation systems had higher soil fertility levels than the continuous single cropping systems. These results confirm that long-term scale planting can reduce spatial variability and dependence of properties and homogenize soil properties. Our findings demonstrated that the changes of cropping systems, the differences of fertilization and the reduction of acid rain were the three important reasons for the changes of soil properties and soil fertility in Jianli county in recent years. In this study area, effective measures should be taken to increase OM, AP and AK contents in soil. • Long-term scale planting can reduce spatial variability of soil properties. • OM, AP and AK are the potential factors restricting soil fertility. • Crop systems and acid rain are the main factors changing soil properties. [ABSTRACT FROM AUTHOR]

One of the major problems limits the applications of perovskite solar cells (PSCs) is the high cost of hole transporting materials (HTMs) and noble metallic electrodes. For HTMs and noble-metal-free PSCs, carbon materials have been utilized as counter electrodes (CEs). In this paper, four kinds of ultra-low-cost bio-carbon materials have been applied and compared in PSCs. Results showed that the photovoltaic performance of PSCs based on different bio-carbon CEs was determined by the interfacial connection, work function (WF), sheet resistance, crystallinity, and morphology of these bio-carbons. The high PCE (12.82%) of PSCs based on bio-carbon CEs has been achieved in current state-of-the-art. PSCs based on bio-carbon CEs was more stable than that of conventional devices, which could retain 87% of their initial PCE after storing for 2000 h in room temperature. Our work proposes a new pathway for the exploration of low-cost bio-carbon materials and could accelerate the applications of PSCs based on carbon electrode. Image 1 [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 MXene-based materials are promising electrode materials for supercapacitors. Herein, Ni 2 CO 3 (OH) 2 nanosheets and/or nanoparticles are in-situ grown on the surface of two-dimensional (2D) Ti 3 C 2 to form Ti 3 C 2 /Ni 2 CO 3 (OH) 2 composites during one-pot hydrothermal processing. The uniform distribution of Ni 2 CO 3 (OH) 2 on Ti 3 C 2 is due to the electrostatic interaction between positively charged nickel ions and negatively charged Ti 3 C 2. Importantly, the electrochemical performance of Ti 3 C 2 /Ni 2 CO 3 (OH) 2 are enhanced. The 30-Ti 3 C 2 /Ni 2 CO 3 (OH) 2 composite electrode exhibits a specific capacity of 173.8 mAh g−1 at 1 A g−1 and excellent cycling stability (capacity retention of 80.1% after 5000 cycles at 10 A g−1). The hybrid supercapacitor using 30-Ti 3 C 2 /Ni 2 CO 3 (OH) 2 composite as positive electrode and active carbon as negative electrode delivers a high energy density of 28.2 Wh kg−1 at a power density of 374.8 W kg−1. The super performance of the composite electrode is attributed to the synergistic effects of good redox activity of Ni 2 CO 3 (OH) 2 particles combined with high electronic conductivity of 2D Ti 3 C 2. The excellent electrochemical performance of Ti 3 C 2 /Ni 2 CO 3 (OH) 2 composite indicates its potential as a promising electrode material to high energy/power density energy storage devices. Graphical abstract Image 1 Highlights • One-pot in-situ synthesis of Ti 3 C 2 /Ni 2 CO 3 (OH) 2 composite is explored. • Synergistic effects of Ni 2 CO 3 (OH) 2 and Ti 3 C 2 enhance the electrochemical performance of composite. • The structure and property of Ti 3 C 2 /Ni 2 CO 3 (OH) 2 composite can be simply controlled by Ti 3 C 2 content. • The 30-Ti 3 C 2 /Ni 2 CO 3 (OH) 2 composite exhibits high specific capacity (173.8 mAh g−1 at 1 A g−1) and good cycling stability. • The 30-Ti 3 C 2 /Ni 2 CO 3 (OH) 2 //AC hybrid supercapacitor exhibits high energy density of 28.2 Wh kg−1 at a power density of 374.8 W kg−1. [ABSTRACT FROM AUTHOR]

In this study, we report a series of carbon/nickel-based composites. The composites are prepared through a facile one-pot solution combustion method by using nickel nitrate hydrate (Ni(NO 3 ) 2 ·6H 2 O) as an oxidizer and glucose (C 6 H 12 O 6 ) as a fuel material. The phase, component and electrochemical capacitive behavior of the as-prepared samples are investigated. The component of the obtained composites could be simply controlled by changing the ratio of NO 3 − /C 6 H 12 O 6 . Novel C/Ni 3 (NO 3 ) 2 (OH) 4 composites are obtained at high molar ratio of NO 3 − /C 6 H 12 O 6 (larger than 9) for the first time. The as-prepared C/Ni 3 (NO 3 ) 2 (OH) 4 composite shows battery-type behavior and exhibits a specific capacity of 630 C g −1 (1260 F g −1 ) at the current density of 1 A g −1 , which is ca. 2–10 fold higher than those of C/NiO composite (414 C g −1 , 828 F g −1 ) and C/NiO/Ni composite (65 C g −1 , 129 F g −1 ). In addition, C/Ni 3 (NO 3 ) 2 (OH) 4 composite exhibits an excellent rate performance (448 C g −1 , 996 F g −1 at 10 A g −1 ) and good cyclic stability. The results indicate that the C/Ni 3 (NO 3 ) 2 (OH) 4 composite is a potential electrode material for electrochemical supercapacitor. This work also suggests that the solution combustion process is promising for large-scale production of materials for supercapacitors. [ABSTRACT FROM AUTHOR]

Soil microbial communities are important for ecological restoration and succession on mine tailings. In the present study, we performed Illumina sequencing to investigate the effects of long term Lespedeza bicolor revegetation on bacterial diversity and community structure in mine tailings under subtropical and moist climatic conditions. Microbial diversity indices (Shannon, OTU number and coverage estimator) of the revegetated soils were higher than that of the control, and increased over sampling period compared to the decreased pattern in the control. Species within known acid tolerant and nutrient regulated genera dominated both revegetated tailings and the control, and exhibited more abundant in the revegetated tailings. At the phylum level, percentage of the Proteobacteria and Actinobacteria were remarkedly higher in revegetated tailings than that in the control, while Chloroflexi performed reversely. Overall, this study found the positive role of L. bicolor revegetation in bacterial diversity development in the acidic mine tailings. Furthermore, the 30-year L. bicolor revegetation made the microbial community structure more homogenizable as a decrease of dissimilarity in tailings was identified over sampling times. Redundancy analysis at the OTU level indicated that Olsen-P and pH were the main regulators of microbial composition, suggesting that soil P and pH are determinant for ecological restoration and microbial community development in acidic mine tailings. [ABSTRACT FROM AUTHOR]

Transition-metal chalcogenides especially MoS 2 are promising candidates as highly efficient electrocatalyst for hydrogen evolution reaction (HER). Nevertheless, the low conductivity and inert basal planes of MoS 2 limit its performance. In addition, the oxygen evolution reaction (OER) catalytic activity of MoS 2 is low. In this work, we report the synthesis of self-supported 1 T-MoS 2 /Co 3 S 4 /Ni 3 S 2 nanoarrays for overall water splitting. 1 T-MoS 2 can enhance electron transfer during the reaction process. Meanwhile, abundant interfaces and defects exist in the heterogeneous catalysts, which can bring more active sites and result in strong interaction among the different components. As a result, the 1 T-MoS 2 /Co 3 S 4 /Ni 3 S 2 nanoarray exhibits low overpotentials of 50 and 240 mV is achieved at 10 mA cm−2 for HER and OER with very high stability. In addition, it can catalyze overall water splitting with a low cell voltage of 1.55 V and 100% Faradic efficiency, demonstrating its practical applications. The present work offers a new route for developing 1 T-MoS 2 based hybrid electrocatalysts with desirable surface and interface structure for energy storage and conversion. [Display omitted] • Self-supported 1 T-MoS 2 /Co 3 S 4 /Ni 3 S 2 nanoarrays was developed for overall water splitting. • The abundant interfaces and defects in 1 T-MoS 2 /Co 3 S 4 /Ni 3 S 2 benefit its catalytic activity. • 1 T-MoS 2 can accelerate electron transfer during the catalytic process. • 1 T-MoS 2 /Co 3 S 4 /Ni 3 S 2 exhibits low HER and OER overpotentials of 50 and 240 mV. • 1 T-MoS 2 /Co 3 S 4 /Ni 3 S 2 can drive full water splitting at 1.55 V with 100% Faradic efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] • As-synthesized Bi 5 Ti 3 FeO 15 naturally contains moderate concentration of oxygen vacancies. • Bi 5 Ti 3 FeO 15 is highly active in piezocatalytic degradation of AO7, MO, RhB, MB and their mixture. • Bi 5 Ti 3 FeO 15 shows superior environmental adaptability and stability. • Real textile wastewater can be efficiently degraded by Bi 5 Ti 3 FeO 15. Piezocatalyst with high and stable efficiency for multiple pollutants degradation shows great promise for practical applications but remains a challenge. Herein, a self-modified oxygen-deficient piezoelectric Bi 5 Ti 3 FeO 15 catalyst is synthesized via a facile method, which demonstrates outstanding piezocatalytic properties. Investigations reveal that an optimal concentration of oxygen vacancies could increase carrier concentration, reduce the electronic impedance and enhance carrier's separation efficiency under ultrasonic vibration, leading to superior piezocatalytic performance. As a result, the typical pollutants acid orange 7, methyl orange, rhodamine B and methylene blue dyes can be efficiently degraded by 98, 95, 94 and 94 %, respectively, within 30 and 50 min (for the latter three dyes), and the acquired degradation efficiencies are higher than most of the previously reported piezocatalysts. Moreover, Bi 5 Ti 3 FeO 15 displayed excellent degradation efficiency for mixed dyes solution with a high first-order rate constant k (0.072 min−1), which is higher than most of the reported piezocatalysts for just single dye degradation. In addition, the Bi 5 Ti 3 FeO 15 catalyst possesses superior environmental adaptability and highly efficient degradation ability for real textile wastewater. This work provides a novel and comprehensive strategy for designing high performance oxygen-deficient piezocatalysts that can be further extended to other Bi-based oxides, and also demonstrates that Bi 5 Ti 3 FeO 15 is a promising eco-friendly and superior piezocatalyst for complex wastewater purification by harvesting mechanical energy. [ABSTRACT FROM AUTHOR]

High-density genetic linkage maps based on single nucleotide polymorphisms (SNPs) are essential for quantitative trait loci (QTL) mapping, trait-related gene identification, marker-assisted selection (MAS), genome assembly, and comparative genomic analysis in aquaculture fish species. Haploid (or gynogenesis) is an excellent germplasm target for mapping genetic linkage maps and MAS breeding. In this study, the high-density genetic linkage map of gynogenetic brown-marbled grouper (Epinephelus fuscoguttatus) based on genotyping by sequencing (GBS) technology was constructed using one F1 gynogenetic family composed of 164 gynogens and their female parents. A high-density linkage map of gynogenetic brown-marbled grouper was constructed with 19,301 SNPs located in 24 linkage groups (LGs). The genetic length of the consensus map was 2343.72 cM, with an average genetic length of 97.655 cM and an average marker interval of 0.12 cM. QTL mapping analysis revealed forty QTLs for body mass and ten phenotypic traits in 9 LGs. Multiple loci were found to be shared on LG3, LG8, LG11, LG16 and LG23, and several important growth-related candidate genes (e.g., mrc1 , adgrb3 , zbtb38 and adcy3), were identified within QTL regions. These vital SNPs and candidate genes may serve as useful genomic tools for marker-assisted selective breeding. Coupled breeding of MAS and artificial gynogenesis could provide a powerful method for genetic improvement in grouper breeding. • The genetic map based on Epinephelus fuscoguttatus , and gynogenetic progeny were constructed. • The genetic linkage map with an average resolution of 0.12 cM per locus was constructed using 19,301 SNPs. • Forty QTLs for eleven growth-related traits were identified on linkage groups. [ABSTRACT FROM AUTHOR]

[Display omitted] • (1 − x)BNT– x BFO solid solutions exhibits enhanced piezocatalytic degradation of MO. • The 0.5BNT–0.5BFO exhibits outstanding piezocatalytic performance and reusability. • Possible piezocatalytic reaction mechanism of 0.5BNT–0.5BFO was proposed. Piezocatalysis has received tremendous interest due to the catalytic effect can be triggered by mechanical vibration. Herein, (1 − x)Bi 0.5 Na 0.5 TiO 3 – x BiFeO 3 solid solution piezocatalysts were synthesized by a sol–gel method aim to improve the piezocatalytic activities of Bi 0.5 Na 0.5 TiO 3 (BNT) and BiFeO 3 (BFO). The piezocatalytic efficiencies of all obtained solid solution catalysts were improved compared with pure BNT and BFO for methyl orange (MO) degradation as expected. Among them, 0.5BNT–0.5BFO catalyst exhibited outstanding piezocatalytic activity and reusability, the reaction rate constant (0.0615 min−1) was about 5.2 and 3.2 times larger than that of BNT and BFO. Trapping experiments demonstrated that O 2 − and OH were the main species for MO degradation. Electrochemical measurements indicated that 0.5BNT–0.5BFO exhibited more efficient charge separation efficiency than that of BNT and BFO, which accounts for its efficient catalytic performance. A possible piezocatalytic reaction mechanism was proposed based on band structure and reactive oxygen species (ROS) detection. This work provides a new perspective for designing highly efficient piezocatalysts. [ABSTRACT FROM AUTHOR]

• Co-Co 6 Mo 6 C 2 @NC nano polyhedron was synthesized using ZIF-67 as a precursor. • The Co 6 Mo 6 C 2 can significantly improve the OER catalytic activity of the catalyst. • The Co-Co 6 Mo 6 C 2 @NC-5 exhibits a low OER overpotential of 270 mV at 10 mA cm−2. • The Co-Co 6 Mo 6 C 2 @NC-5 exhibits a high ORR half-wave potential of 0.80 V. • The Co-Co 6 Mo 6 C 2 @NC can be used as a bifunctional electrocatalyst for Zn-air battery. A high effective bifunctional electrocatalyst was developed for rechargeable Zn-air batteries by rational integrating high active Co sites for ORR and Co 6 Mo 6 C 2 specie for OER. [Display omitted] To facilitate the development of rechargeable metal-air batteries, the exploration of high effective bifunctional electrocatalysts is essential. In this work, we report a facile strategy to synthesize N doped carbon (NC) encapsulated Co-Co 6 Mo 6 C 2 (Co-Co 6 Mo 6 C 2 @NC) nano polyhedron using ZIF-67 as a precursor and investigated its catalytic performance for both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). The introduction of Co 6 Mo 6 C 2 into Co@NC can significantly improve the OER catalytic activity of the catalyst, while the high ORR catalytic activity of the catalyst is maintained. Specifically, Co-Co 6 Mo 6 C 2 @NC-5 shows a decent half-wave potential of 0.80 V for ORR, and a very low overpotential of 270 mV at 10 mA cm−2 for OER, demonstrating its bifunctional activity. The rechargeable Zn-air battery assembled using Co-Co 6 Mo 6 C 2 @NC-5 exhibits a maximum power density of 90.75 mW cm−2 and a high specific capacity of 768 mA h g−1, as well as good durability of 50 h without attenuation in performance, highlighting its practical application. [ABSTRACT FROM AUTHOR]

• High DOM chemodiversity is ubiquitous in all headwater streams and a large river. • S-containing and aliphatic compounds originate from rural domestic effluent. • Ecosystem respiration can be controlled by anthropogenic sources of DOM. • H/C of 1.07 and O/C of 0.37 were typical precursors of DBPs. • DOM with 151 to 635 Da was the main part that was hard to remove through degradation. Dissolved organic matter (DOM) is a complicated assembly of organic molecules, including thousands of molecules with various structures and properties. However, how the stream DOM sources respond to carbon compositions and the transformation processes remains unclear. In this study, the chemical characteristics and spectral and mass spectrometry (FT-ICR MS) of DOM were analyzed. Six sampling points of headwater stream (HWSs) were sampled, and an effluent polluted stream (WSR) and a main stream of the Changjiang River (DT) were also sampled for comparison. In situ degradation experiments and FT-ICR MS analysis were also performed to observe the dynamic processes of DOM in HWS. The results showed that the anthropogenic markers of sewage (i.e. sulfur (S) compounds and marker from antibiotics and estrogen) in HWS were higher than those in DT. The molecular weight decreased while the degradation products (S-containing compounds and unsaturated compounds (HU)) increased after in situ degradation due to the influence of both the photodegradation and biodegradation process. In addition, the KMD plots showed that the DOM homologue intensities in range 400–600 Da changed significantly after demethylation by biodegradation. The components of highly refractory substances and the degradation degree of DOM in DT was higher than that in HWS. We extracted the refractory DOM pool in HWS, which was mainly small molecular with molecular weights < 600 Da. These molecular will be difficult to remove in traditional drinking water treatment processes and easily produced disinfection byproducts (DBPs). This study emphasized the necessity of identifying the sources and transformation processes of DOM in HWS and clarified the types and characteristics of DOM that should be considered in future drinking water treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

The influence of rare earth on the microstructures as well as properties of Al and its alloys has attracted great attention recently. However, contradictory results always were reported, some previous studies found that rare earth promoted the increment of the tensile properties of Al alloy, some other researchers though rare earth had no significant effect on the tensile properties or decreased the tensile properties. In the present work, the effects of minor rare earth element La on the solidification, aging behaviors and the tensile properties of Al-Mg-Si alloys have investigated by thermal analysis, microstructural characterizations and properties tests. The results demonstrate that the ultimate tensile strength and yield strength of Al-Mg-Si alloy can be increased by adding minor rare earth La. The effect mechanism of La has also been explored, it indicates that minor La enhances the strength of the Al-Mg-Si alloy by decreasing grain size and promoting the precipitation of (Mg, Si) phase. This study provides a way for manufacturing Al-Mg-Si alloys with excellent mechanical properties. • Trace La addition can refine α-Al and promote the precipitation of Mg 2 Si and β ′ phase. • Trace La addition significantly improve the mechanical properties of Al-Mg-Si alloy. • The effect mechanisms of trace La addition on Al-Mg-Si alloy have been clarified. [ABSTRACT FROM AUTHOR]

Highlights: [•] A rapid, accurate CLEIA technique was developed for analysis and screening of the ENR residual in food samples. [•] Compared with the commonly used methods of HPLC and ELISA, the CLEIA method is more simple, specific, accurate and sensitive. [•] CLEIA method is suitable for rapid detection of a large number of samples and on-site screening. [•] A good and fresh clue was provided in this study for analysis and determination of residues of drugs in food samples. [ABSTRACT FROM AUTHOR]

Abstract: Theoretical and experimental investigations have demonstrated that full bandgaps are not easy to achieve in the face-centered cubic (fcc) unary and binary structures; even for unary inverse opals with high refractive index network, the bandgaps are not as large as 1D or 2D structures. In this work, we simulated the bandgap of a binary inverse opal, which is over 16% larger than that of a unary inverse crystal. Two kinds of binary colloidal crystals and their inverse structures have been fabricated by a horizontal deposition method. [Copyright &y& Elsevier]

The effects of rare earth element on the microstructures, tensile properties and electrical properties of aluminum alloys have brought about widespread interesting in the last few decades. However, contradictory results are usually reported, and there is little research concerning the effect law of trace lanthanum (the addition is below 0.1 wt%) on the as-cast microstructures, electrical conductivity and the tensile properties of 8176 aluminum alloy which is one of the most widely used aluminum conductor alloy. In this work, solidification experiments were performed with 8176 aluminum alloy and the effects of lanthanum addition was investigated. The results demonstrated that the lanthanum addition can promote the refinement of the alpha Al grains, the modification of Al 13 Fe 4 intermetallic phase. The elongation and electrical conductivity simultaneously enhance with lanthanum addition when the additive amount is less than 0.08%, while the elongation decreases when the additive amount reaches to 0.1% due to the formation of intermetallic phase. The enhancement of the elongation is mainly ascribed to the modification of Al 13 Fe 4 intermetallic phase, the enhancement of the electrical conductivity is attributed to the reduction of solid solubility of Si and Fe elements in Al matrix. These results indicate that the addition of micro-alloying element lanthanum is a prospective method for simultaneously elevating the electrical conductivity and tensile properties of the 8176 aluminum alloy. • The elongation and electrical conductivity can be simultaneously improved by trace La addition. • Trace La can work as a surfactant and thus refine the α-Al grains. • Trace La modifies Al 13 Fe 4 phase by absorbing in the growth edges. • The improvement of elongation induced by trace La is ascribed to the modification of Al 13 Fe 4 phase. • The improvement of electrical conductivity is ascribed to the reduction of Si and Fe solute content. [ABSTRACT FROM AUTHOR]

• Theoretical calculation is an effective way for choosing corrosion inhibitors. • DFT and MD were used to study the effect of PEG and PAM. • The effect of degree of polymerization on adsorption behavior was studied. • The study may provide a theoretical basis and guidance for further experiments. Metal corrosion is an important technical problem often encountered in industrial production in various fields. One of the efficient and economical methods to effectively block corrosion is to add a corrosion inhibitor, which forms a protective film on the metal surface. Accordingly, environmentally friendly organic corrosion inhibitors have become research hotspots in recent years. Among them, polyorganic substances have been proved to be effective corrosion inhibitors; however, research on this topic is still scarce. In this study, (poly) ethylene glycol and (poly) acrylamide are investigated as polyorganic inhibitors by density functional theory and molecular dynamic simulation, and the effect of the degree of polymerization (DP) on the adsorption behavior on metal surfaces is theoretically analyzed. On the basis of a comprehensive evaluation of their stability and adsorption energy, the optimal DPs of these two inhibitors are determined. This work may provide a theoretical basis and guidance for further research of corrosion inhibitor. [ABSTRACT FROM AUTHOR]

Nanotube assembled coral-like ZnS@N, S co-doped carbon was synthesized by a facile and convenient method, and the material exhibits outstanding stability and rate performance as a sodium-ion batteries anode material. • Nanotube assembled coral-like ZnS@N, S co-doped carbon was synthesized. • ZnS@NSC-800 shows outstanding rate performance of 417.1 mAh g−1 at 10 A g−1. • ZnS@NSC-800 also shows excellent cycling stability for SIBs. • The Na+ storage mechanism are mainly based on capacitive contribution. Developing advanced Na-host anode materials to enhance the stability and rate performance of Sodium Ion Batteries (SIBs) is the premises for their commercialization. Herein, we report a template method to prepare coral-like ZnS embedding in N, S co-doped carbon (ZnS@NSC) as an anode material for SIBs. The heteroatom doped carbon endows the materials with high conductivity and structure stability. The nanotube structure provides high specific area and adequate space for the volume expansion during charge/discharge process. The coral-like structure can further increase the mass transport. Therefore, the merits of the materials are fully utilized and thus outstanding sodium storage performances are achieved. To the best of our knowledge, the ZnS@NSC-800 shows the best rate performance (417.1 mAh g−1 at 10 A g−1) and cycling stability (98.4% capacity was retained after 1000 cycles at 1 A g−1) to date. Combining with the high capacity, facile and convenient method, and the usage of low-cost and nontoxic raw materials, the material exhibits great potential for SIBs. [ABSTRACT FROM AUTHOR]

• Mechanism of NRR occurred on Ru/graphene catalysts were studied by DFT. • The effects of Ru atom numbers and Ru atom distribution on Ru/Gr were studied. • Provide guidance for the design and preparation of NRR catalysts. As a more common catalyst material in nitrogen reduction reactions (NRR), Ru has high activity and considerable catalytic performance, but it is expensive with scarce reserves. These factors limit the development of Ru in NRR, how to reduce costs and increase the utilization of precious metals is a problem facing the development of Ru-based catalysts. Graphene is considered as a promising carrier material, which can increase the specific surface area and dispersibility of the catalyst, thereby improving the utilization rate of materials. Therefore we combined these two materials and studied the mechanism of NRR occurred on Ru/graphene (Gr) catalysts by density functional theory (DFT) method. The effects of different numbers of Ru atoms and Ru atom distribution on the catalytic activity of Ru/Gr catalyst were calculated. A series of data such as the adsorption free energy and reaction path were obtained. The final results show that the double Ru supported graphite nitrogen doped Gr with single adsorption process and the three Ru supported pyrrole nitrogen doped Gr with double adsorption process have the best NRR activity. Compared with catalyst-free process, the presence of the catalyst effectively reduces the reaction energy barrier and improves the reaction activity. The research results provide guidance for the design and preparation of high-performance NRR catalysts to a certain extent. [ABSTRACT FROM AUTHOR]

Designing porous materials with various nanoscales and dimensionalities is very significant for surface/interfacial interaction and mass transport, and are expected to improve the performance of materials. Herein, we first report the preparation of porous NiCo layered double hydroxide (NiCo LDH) nanotube by utilizing a metal organic framework (MOF) and MoO 3 composite as a precursor. The NiCo LDH nanotube is composed of two-dimension (2D) nanosheet and a high specific surface area of 107 m2 g−1 is achieved. The unique structure of nanotube and high specific surface area can greatly improve the electrical conductivity and electroactive surface area of the material and also shorten the ion transport path, resulting in enhancement of electrochemical performance. When used as electrode material for supercapacitors, the NiCo LDH nanotube shows a high specific capacitance of 1386 F g−1 at a current density of 1 A g−1. Moreover, the asymmetric supercapacitor assembled by active carbon and the NiCo LDH nanotube shows a high capacitance of 94.3 F g−1 at 0.5 A g−1, an energy density of 118 Wh kg−1 at a power density of 108 W kg−1 and excellent stability without any loss in capacitance even after 10000 charge-discharge cycles, indicating that the NiCo LDH nanotube is a very promising supercapacitor electrode material. NiCo layered double hydroxide (NiCo LDH) nanotube was synthesized and exhibited high specific capacitance and excellent ling-term stability. Image 1 • NiCo LDH nanotube was prepared by using MoO 3 @ZIF-67 as precursor for the first time. • The NiCo LDH nanotube is assembled by 2D nanosheet. • The NiCo LDH nanotube shows a high capacitance of 1386 F g−1 at 1 A g−1. • The NiCo LDH//AC shows a high capacitance of 94.3 F g−1 at 0.5 A g−1 and excellent stability. [ABSTRACT FROM AUTHOR]