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Ammonia removal by nitrifiers at the extremely high salinity poses a great challenge for saline wastewater treatment. Sequencing batch reactor (SBR) was conducted with a stepwise increase of salinity from 10 to 40 g-NaCl·L−1, while sequencing batch biofilm reactor (SBBR) with one-step salinity enhancement, their nitrification performance, microbial structure and interaction were evaluated. Both SBR and SBBR can achieve high-efficiency nitrification (98% ammonia removal) at 40 g-NaCl·L−1. However, SBBR showed more stable nitrification performance than SBR at 40 g-NaCl·L−1 after a shorter adaptation period of 4–15 d compared to previous studies. High-throughput sequencing and metagenomic analysis demonstrated that the abundance and capability of conventional ammonia-oxidizing bacteria (Nitrosomonas) were suppressed in SBBR relative to SBR. Gelidibacter , Anaerolineales were the predominant genus in SBBR, which were not found in SBR. NorB and nosZ responsible for reducing NO to N 2 O and reducing N 2 O to N 2 respectively had s strong synergistic effect in SBBR. This study will provide a valuable reference for the startup of nitrification process within a short period of time under the extremely high NaCl salinity. [Display omitted] • High efficiency nitrification was achieved in SBR and SBBR at the salinity of 40 g-NaCl L−1. • SBBR showed more stable nitrification performance than SBR after adapting to 4% NaCl salinity within 20 days. • No nitrite accumulation was found at the stable nitrification period under varying salinity. • More abundant microbial diversity prevailed in SBBR, especially anaerobic bacteria replacing nitrifiers as the dominant genus. • Synergistic interactions between norB and nosZ were induced by microaerobic zones in SBBR. [ABSTRACT FROM AUTHOR]

Bis(2-ethylhexyl) phthalate (DEHP) has been widely concerned owing to its widespread detection and endocrine disrupting effect. Nevertheless, systematic analysis and evaluation of the current status of DEHP contamination are still insufficient for children and adolescents. Dietary exposure and nondietary exposure to DEHP were investigated to estimate the total average daily dose (ADD). The top three contributors were dust exposure, edible oil and vegetable intake. Dietary intake contributed highly (70%) to daily exposure to DEHP. By analyzing the monitoring data on DEHP exposure, the cumulative health risks of DEHP were assessed for different age groups of children and adolescents in East China. The probability distributions of noncarcinogenic and carcinogenic risks were determined by Monte Carlo simulation. The results showed that the risk level reduced with age. The predicted mean noncarcinogenic and carcinogenic risks for all age groups exceeded the acceptable level, indicating that the general population would be at high risk by DEHP overexposure. Schoolchildren at ages 6∼<9 were more susceptible to DEHP exposure, with a 30% possibility of exceeding the safety limit Based on these results, gradual banning and restriction should be carried out to decrease DEHP contamination and potential health risks. • Dietary intake accounted for nearly 70% of daily DEHP exposure. • DEHP exposure could represent a possible health concern for children and adolescents. • The difference of ADD in females and males was insignificant. • 30% of the possibility for schoolchildren exceed the safety limit in East China. [ABSTRACT FROM AUTHOR]

Abstract Cell division cycle 25 B (CDC25B) is a member of the CDC25 phosphatase family. It can dephosphorylate cyclin-dependent kinases and regulate the cell division cycle. Moreover, siRNA knockdown of CDC25B impairs influenza A virus (IAV) replication. Here, to further understand the regulatory mechanism of CDC25B for IAV replication, a CDC25B-knockout (KO) 293T cell line was constructed using CRISPR/Cas9. The present data indicated that the replication of IAV was decreased in CDC25B-KO cells. Additionally, CDC25B deficiency damaged viral polymerase activity, nucleoprotein (NP) self-oligomerization, and NP nuclear export. Most importantly, we found that the NP phosphorylation levels were significantly increased in CDC25B-KO cells. These findings indicate that CDC25B facilitates the dephosphorylation of NP, which is vital for regulating NP functions and the life cycle of IAV. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is one of the most toxic pollutants to aquatic organisms. The influence of salinity on Hg toxicity, an important factor restricting the development of global marine aquatic life criteria (ALC), is unclear. Therefore, mercury toxicity data were corrected based on salinity using the aggregate slope method, and the ALC values were derived. Short-term aquatic life criteria (SALC) and long-term aquatic life criteria (LALC) were derived using the species sensitivity distribution method based on Log-logistic, Log-normal, Burr III, Gumbel, and Weibull models. The hazard quotient (HQ) and joint probability curve (JPC) methods were used to evaluate the ecological risk of Hg in the coastal waters of China. The results showed that the SALC and LALC of Hg in the coastal waters of China were 2.21 and 0.54 μg/L. The toxicity data and salinity were positively correlated for Chordate and Arthropoda and negatively correlated for Mollusca. The SALC values increased by approximately 75%, with salinities ranging from 10 to 20 ppt. A slight peak in the SALC at mid-salinities was also observed. The ecological risk assessment of Hg in China's coastal waters showed that attention should be paid to Hg pollution in the Bohai Sea and East China Sea, especially the ecological risk of Hg to crustacean organisms. This study could promote the development of water quality criteria for coastal waters and provide a technical reference for mercury management in the coastal waters of China. • Temporal and spatial distribution of Hg in China's coastal waters were analyzed. • The SALC and LALC were derived based on species sensitivity distribution method. • Salinity correction method was used to study effect of salinity on toxicity and ALC. • HQ and JPC methods were used to assess Hg's ecological risk in China's coastal waters. [ABSTRACT FROM AUTHOR]

The androgen receptor (AR) plays critical roles in human prostate carcinoma progression and transformation. However, the activation of AR is regulated by co-regulators. MEIS1 protein, the homeodomain transcription factor, exhibited a decreased level in poor-prognosis prostate tumors. In this study, we investigated a potential interaction between MEIS1 and AR. We found that overexpression of MEIS1 inhibited the AR transcriptional activity and reduced the expression of AR target gene. A potential protein–protein interaction between AR and MEIS1 was identified by the immunoprecipitation and GST pull-down assays. Furthermore, MEIS1 modulated AR cytoplasm/nucleus translocation and the recruitment to androgen response element in prostate specific antigen ( PSA ) gene promoter sequences. In addition, MEIS1 promoted the recruitment of NCoR and SMRT in the presence of R1881. Finally, MEIS1 inhibited the proliferation and anchor-independent growth of LNCaP cells. Taken together, our data suggests that MEIS1 functions as a novel AR co-repressor. [ABSTRACT FROM AUTHOR]

Abstract: Nucleic acid molecular probes (NAMPs) have been widely used in the sensing of various chemical and biological substances, as well as physical parameters. However, for traditional nucleic acid molecular probes, the stoichiometric 1:1 binding ratio limits the signal enhancement and thus the sensitivity of the assay. In order to overcome this problem, the cyclic enzymatic amplification method (CEAM) based on exonuclease III has been applied in optical and electrical detection of DNA, proteins and small molecules with excellent sensitivity, selectivity, versatility and simplicity. In this review, the working principle of CEAM is first introduced, followed by the applications of CEAM using different output signals for various analytes. Finally, experimental designs and procedures of CEAM are discussed in detail using displacing probes-based CEAM and linear molecular beacons (LMBs)-based CEAM as two examples. [Copyright &y& Elsevier]

Abstract: Aphids cause much damage to Chinese cabbage in northern China. Over reliance on pesticides have large environmental and human health costs that compel researchers to seek alternative management tactics for aphid control. The component of aphid alarm pheromone, E-β-Farnesene (EβF), extracted from Matricaria chamomilla L., which attracts natural enemies in the laboratory, may have significant implications for the design of cabbage aphid control strategies. The purpose of this paper is to understand the effects of EβF on natural enemies to cabbage aphid control in Chinese cabbage fields. Ladybeetles on Chinese cabbage leaves in EβF released plots and Aphidiidae in EβF released yellow traps were significantly higher than those of in controls. No significant differences were detected in the interactions of different treatments and the two years for all natural enemies. More important, lower aphid densities were found in EβF released plots. Our results suggested that the EβF extracted from M. chamomilla L. could attract natural enemies to reduce cabbage aphids in the Chinese cabbage fields. [Copyright &y& Elsevier]

Catalysts of multiphase nickel sulfide coupling with CeO 2 (NiS x /CeO 2 /NF) are fabricated through one step hydrothermal and calcination process. The as-obtained NiS x /CeO 2 /NF exhibits excellent activity towards overall water splitting reaction with a low potential of 1.53 V for 10 mA cm−2 in 1 M KOH. [Display omitted] Constructing nanostructured electrocatalysts with heterointerface and finetuning their electronic properties are essential for high-efficient overall water splitting. Here, we prepared a well-designed nano-flower-like multiphase and hybrid material of NiS/NiS 2 /CeO 2 /NF (NiS x /CeO 2 /NF) with rich heterointerfaces and abundant active sites through solvothermal reaction and post-annealing treatment. The as-fabricated NiS x /CeO 2 /NF exhibits exceptional catalytic performance for OER and HER. Specifically, in 1 M KOH solution, it requires the low overpotentials of 326 and 92 mV to achieve the current density of 200 and 10 mA cm−2 for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), respectively. More satisfactorily, when NiS x /CeO 2 /NF is used as the bifunctional catalyst, a low voltage of only 1.53 V is required to achieve a current density of 10 mA cm−2 for overall water splitting. The excellent catalytic performance should be attributed to its special heterogeneous structure and the synergy effect between NiS x and CeO 2. This work emphasizes the important significance of constructing efficient bifunctional electrocatalysts by reasonably designing heterostructures and multiphase components for overall water splitting. [ABSTRACT FROM AUTHOR]

[Display omitted] Designing heterojunction catalysts with energy effects at the interface, particularly combining the surface structure advantages of super-hydrophilic interfaces with the high activity advantages of bimetal synergistic optimisation, is the key to developing economical and efficient industrial electrocatalytic water-splitting catalysts. In this study, a coupled nanoflower-like NiFe(OH) x /(Ni, Fe)Se heterostructure catalyst supported on Ni foam (NF) (NFSe@NFOH/NF) was designed and successfully prepared using hydrothermal and electrodeposition strategies. Owing to the electron interaction at the heterogeneous amorphous (NFOH)/crystalline (NFSe) interface and the bimetallic synergistic effect of Ni and Fe, the prepared NFSe@NFOH/NF exhibited excellent and stable oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) catalytic properties, with low overpotentials of 214/276 mV at 100 mA⋅cm−2 and 262/340 mV at 500 mA⋅cm−2. The assembled water electrolyser comprising NFSe@NFOH/NF || NFSe@NFOH/NF needed only small voltages of 1.73 and 1.85 V to yield current densities of 100 and 500 mA⋅cm−2, respectively. This study offers an innovative design idea for the rational adoption of interface engineering and amorphous–crystalline engineering techniques to construct catalysts with excellent catalytic activity and stability for electrocatalytic overall water splitting (EOWS) at a high current density, which further facilitates the advancement of sustainable energy technology in the future. [ABSTRACT FROM AUTHOR]

In response to the stress of infection, Mycobacterium tuberculosis (Mtb) reprograms its metabolism to accommodate nutrient and energetic demands in a changing environment. Pyruvate kinase (PYK) is an essential glycolytic enzyme in the phosphoenolpyruvate–pyruvate–oxaloacetate node that is a central switch point for carbon flux distribution. Here we show that the competitive binding of pentose monophosphate inhibitors or the activator glucose 6-phosphate (G6P) to Mtb PYK tightly regulates the metabolic flux. Intriguingly, pentose monophosphates were found to share the same binding site with G6P. The determination of a crystal structure of Mtb PYK with bound ribose 5-phosphate (R5P), combined with biochemical analyses and molecular dynamic simulations, revealed that the allosteric inhibitor pentose monophosphate increases PYK structural dynamics, weakens the structural network communication, and impairs substrate binding. G6P, on the other hand, primes and activates the tetramer by decreasing protein flexibility and strengthening allosteric coupling. Therefore, we propose that Mtb PYK uses these differences in conformational dynamics to up- and down-regulate enzymic activity. Importantly, metabolome profiling in mycobacteria reveals a significant increase in the levels of pentose monophosphate during hypoxia, which provides insights into how PYK uses dynamics of the tetramer as a competitive allosteric mechanism to retard glycolysis and facilitate metabolic reprogramming toward the pentose-phosphate pathway for achieving redox balance and an anticipatory metabolic response in Mtb. Unlabelled Image [ABSTRACT FROM AUTHOR]

[Display omitted] • Precise and nondestructive preparation of functional graphene materials with perfect lattice and well-defined chemical structure through graphite reduction mode. • Establishing clear structure–property relationships and engineering graphene electronic effects to regulate lithium-storage properties. • High-performance, electron-donating-group-functionalized graphene electrode for lithium-ion batteries. Organic functionalization of graphene framework was an effective means used to boost the storage performances of lithium, but it lacked a universal strategic guideline for introducing functional groups (electron-withdrawing and electron-donating modules are overall classified). It mainly entailed designing and synthesizing graphene derivatives, in which the interference functional groups were necessarily excluded. To this end, a unique synthetic methodology based on graphite reduction cascaded by electrophilic reaction was developed. The electron-withdrawing-type groups (Br; trifluoroacetyl: TFAc) and electron-donating-type counterparts (butyl: Bu; 4-methoxyphenyl: 4-MeOPh) were readily attached to graphene sheets at a comparable functionalization degree. As the electron density of carbon skeleton was enriched by electron-donating modules, particularly for Bu units, the lithium-storage capacity, rate capability and cyclability were appreciably boosted. For example, they had 512 and 286 mA h g−1 at 0.5C and 2C, respectively; and 88 % of capacity retention after 500 cycles at 1C. [ABSTRACT FROM AUTHOR]

Ru@Fe-Ni(OH) 2 /NF catalyst fabricated through Fe-doped and interfacial Ru nanoclusters co-engineering of Ni(OH) 2 nanosheets directly grafted on Ni foam exhibits excellent activity towards oxygen evolution reaction (OER) in alkaline media with an overpotential of 266.4 mV to achieving a current density of 50 mA cm−2 in 1 M KOH. Our results show that we have successfully developed an efficient OER catalyst for green and efficient electrocatalytic hydrolysis to produce H 2 and O 2 , providing a promising method for clean H 2 production. [Display omitted] The creation of inexpensive, high-performance catalysts to reduce the overpotential of the oxygen evolution reaction (OER) process is critical for the electrolysis of water for hydrogen production. Therefore, we applied a one-step hydrothermal method using cation exchange reaction (CER) to prepare Fe-doped and interfacial Ru nanoclusters co-engineered Ni(OH) 2 nanosheets directly grafted on Ni foam (Ru@Fe-Ni(OH) 2 /NF) for OER process. Results of electrochemical tests reveal that Ru@Fe-Ni(OH) 2 /NF has excellent OER activity, and its overpotential (η) is only 266.4 mV when the current density is 50 mA cm−2 in 1 M KOH solution, even lower than that of commercial OER catalyst RuO 2 (355 mV). The Tafel slope also decreases from 133.8 mV dec−1 for pristine Ni(OH) 2 /NF material to 24.1 mV dec−1 for Ru@Fe-Ni(OH) 2 /NF, indicating the higher charge transfer rates and fastest kinetics for water oxidation. At an overpotential of 300 mV the optimal turnover frequency (TOF) of 0.062 s−1 for Ru@Fe-Ni(OH) 2 /NF is achieved compared to that of Ni(OH) 2 /NF (0.014 s−1, NN), demonstrating the fast reaction kinetics of the as-prepared electrocatcalyst. After 24 h stability test, the catalytic activity of Ru@Fe-Ni(OH) 2 /NF was only attenuated by 2 %, showing excellent OER stability and durability. Our results show that we have successfully developed an efficient OER catalyst for green and efficient electrocatalytic hydrolysis to produce H 2 and O 2 , providing a promising method for clean H 2 production. [ABSTRACT FROM AUTHOR]

To elucidate how different spatial oxygen-containing groups influenced lithium-storage performance of graphene matrix, and further establish a clear structure-performance relationship, graphene framework was strategically functionalized with carboxylate and sulfonate groups and oxygen-free aniline ones as a reference. Due to maximum lithiation effect, spatially sulfonate functionalized graphene delivered the best electrochemical performances in lithium-ion batteries. [Display omitted] Graphene derivative materials are widely used as anode component in lithium-ion batteries. However, there is still a lack of reliable and foresighted guides helpful for designing high-performance graphene-based electrode materials. To this end, we strategically chose challenging graphite fluoride as starting material for the derivatization of graphene in order to exclude interference factors. As a result, graphene framework was functionalized with oxygen-containing carboxylate and sulfonate groups and oxygen-free aniline units at a similar functionalization degree. Due to the strong effect of lithiation, out-of-plane p -aminobenzoic acid blocks boosted the lithium-storage capacity of graphene matrix to 636 mAh g−1 at 0.1 A/g, and sulfanilic acid blocks maximized this value to 873 mAh g−1. Sadly, oxygen-free aniline functionalized graphene material only delivered a specific capacity of 88 mAh g−1. Meanwhile, spatial lithiated carboxylate and sulfonate units endowed graphene framework with better rate capability and cycling stability. Such a structure-performance relationship established herein was beneficial for the design and preparation of high-performance graphene derivative electrode materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • This study realizes rational construction of the hierarchical wing-like iron/molybdenum oxide heterojunction on nickel foam (FMO/NF). • Hierarchical porous structure composed of the nanoparticle-micron sheets facilitates electrolyte/catalyst contact and bubble release. • The synergistic effect of Fe and Mo combined with the interfacial effect of the heterojunction optimizing structural configurations. • FMO/NF exhibits distinguished performance for overall water splitting in alkaline solution. Designing heterojunction catalysts with high-energy interfacial effects, especially combining the geometrical advantages of hierarchical micro-nano structures with the advantages of bi- or multi-metal syergistically optimised electronic coordination environments, is crucial for achieving efficient and stable water splitting. In this study, a simple one-step hydrothermal method was used to construct a hierarchical wing-like iron/molybdenum oxide heterojunction with a porous structure on nickel foam (FMO/NF). The synergistic effect of Fe, Mo, and the heterostructures can enrich structural defects, overcome the disadvantages of the individual components, and improve material performance by optimising the structural configurations and electronic properties and exploiting the electronic interactions that occur between interfaces composed of different phases. In addition, owing to the high porosity of the hierarchical micro-nano structure and abundant active sites, the wing-like FMO/NF was utilised as an efficient bifunctional catalyst for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), presenting low overpotentials of 278.06 and 263.72 mV, respectively, at a current density of 100 mA·cm−2 in 1 mol/L KOH. Furthermore, assembling FMO/NF as both the anode and cathode (FMO/NF || FMO/NF) required a cell voltage of 1.87 V to drive 100 mA·cm−2 in 1 mol/L KOH, and it proceeded continuously for 110 h with negligible cell voltage decay. This work provides a rational synthetic route for the preparation of innovative double transition metal-based micro-nano hierarchical heterostructured electrocatalysts with a synergistic effect and further advances the development of energy-conversion technology. [ABSTRACT FROM AUTHOR]

[Display omitted] Exploration of highly efficient and cost-effective oxygen evolution reaction (OER) electrocatalysts is of crucial importance for the development of water splitting. In recent years, Cu-based materials have been widely concerned in OER due to their non-toxicity, rich reserves and highest reversibility. Meanwhile, Cu x O nanorods is easy to be prepared in industry. Herein, we report a fast preparation method to construct an integrated Cu x O@CoNi-LDH electrocatalyst with a unique 1D nanowire-2D nanosheet hierarchical core–shell structure by electrodepositing CoNi-LDH nanosheet arrays directly onto Cu x O nanorods (Cu x O were in situ-created on the Cu foam) at a large deposition voltage of −3.0 V vs SCE. The unique heterogeneous core–shell nanostructure, large deposition amount of CoNi-LDH and the synergistic effects between Cu x O core and CoNi-LDH shell can provide abundant active sites, rich open-channels and reduced charge transfer resistance (R ct) for effective oxygen release and facile electron transport. Consequently, the optimized Cu x O@CoNi-LDH/CF exhibits a low overpotential of 207 mV in 1 M KOH solution at the current density of 10 mV cm−2 and a small Tafel slope of 50.1 mV dec−1. After 60 h of long-term stability test, the catalytic performance is only slightly weakened. This work demonstrates a new approach to design the high-performance LDH and Cu-related OER catalysts by constructing a unique hierarchical core–shell nanostructure. [ABSTRACT FROM AUTHOR]

[Display omitted] • Self-supported hierarchical Co 3 S 4 /CeO 2 nanorod array is fabricated via a facile one-step hydrothermal method. • Hierarchical heterostructured Co 3 S 4 /CeO 2 acts as efficient catalyst for overall water splitting, demonstrating superior activity and stability. • The introduction of CeO 2 greatly enhances the OER catalytical activity of Co 3 S 4 as illustrated by DFT calculation. Herein, a hierarchical Co 3 S 4 / CeO 2 nanorod array on cobalt foam (Co 3 S 4 / CeO 2 -CF) was successfully constructed via a facile one-step hydrothermal method. The fabrication of Co 3 S 4 / CeO 2 -CF was confirmed by X-ray diffraction, scanning electron microscope (SEM), high resolution transmission electron microscope (HRTEM). It is observed that CeO 2 nanorod was fully covered with Co 3 S 4 nanosheets, forming a hierarchical core–shell nanostructure. Furthermore, CeO 2 and Co 3 S 4 were doped with each other during the one-step hydrothermal process, forming a heterogeneous Co 3 S 4 / CeO 2 nanostructure. Density functional theory (DFT) calculations suggest that the introduction of CeO 2 in Co 3 S 4 is effective in reducing the free energy barrier of OER process. To achieve current density of 10 mA cm−2, only small overpotentials of 74.9 mV and 213 mV are required for HER and OER in 1.0 M KOH solution, respectively. In particular, the Co 3 S 4 / CeO 2 -CF based electrolysis cell for overall water splitting only needs an output voltage of 1.64 V in the alkaline medium, lower than that of Pt/C–RuO 2 -based electrolysis cells (1.70 V). Such hierarchical heterogeneous catalyst also shows ultra-stable catalytic activity. Therefore, with the favorable heterointerfaces and hierarchical structures, Co 3 S 4 / CeO 2 -CF could be a promising bifunctional electrocatalyst for overall water splitting and this study may also provide a facile method for the preparation of hierarchical heterogeneous nanostructured materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • MgCo 2 O 4 @NiMn-LDH core-shell nanoarrays is fabricated on Ni foams. • The materials are obtained by a facile hydrothermal strategy. • MgCo 2 O 4 @NiMn-LDH electrode exhibits superb supercapacitive performance. In this work, MgCo 2 O 4 @NiMn layered double hydroxide (LDH) core-shell structured nanocomposites on Ni foam (NF) are synthesized by facile hydrothermal and calcination methods. MgCo 2 O 4 /NF is synthesized first via a hydrothermal reaction and annealing treatment, and then utilized to prepare MgCo 2 O 4 @NiMn-LDH/NF core-shell structured nanocomposites via the second hydrothermal process. It is found that the MgCo 2 O 4 @NiMn-LDH/NF nanocomposite prepared from 6 h hydrothermal reaction (MC@NM-LDH-2) exhibits an excellent specific capacitance of 3757.2 F g−1 (at 1 A g−1). Moreover, a high capacitance retention (86.9% after 6000 cycles) and a low internal resistance (Rs) (0.565 Ω) can be achieved. Furthermore, an all-solid-state asymmetric supercapacitor (ASC) is assembled using MgCo 2 O 4 @NiMn-LDH/NF-2 as positive electrode and activated carbon (AC) as negative electrode. The as-fabricated MgCo 2 O 4 @NiMn-LDH/NF-2//AC ASC shows a high energy density of 62.33 Wh kg−1 at 750 W kg−1. Meanwhile, the MgCo 2 O 4 @NiMn-LDH/NF-2//AC ASC device possesses an outstanding cycling stability of 93.7% retention of the initial capacitance after 6000 cycles and three ASC devices connected in series can light up a LED bulb for 15 min. Our results manifest that these core-shell structure MgCo 2 O 4 @NiMn-LDH nanocomposites could envision huge potential application in energy storage devices. [ABSTRACT FROM AUTHOR]

• Mo 3 S 4 /Co 1-x S nanosheets are synthesized by a simple one-step hydrothermal method. • Mo 3 S 4 /Co 1-x S@CF-8 has high hydrophilicity. • The bimetallic sulfide compound has high catalytic activity. • Mo 3 S 4 /Co 1-x S@CF-8 can achieve efficient overall water splitting. Hydrogen generation through electrochemical water decomposition is a promising method to address the global energy crisis. Herein, we report the synthesis of a series of flower-like Mo 3 S 4 /Co 1-x S composites on Co foil (Mo 3 S 4 /Co 1-x S@CF) as high-performance electrochemical water-splitting catalysts in an alkaline environment. The flower-like array structure of Mo 3 S 4 /Co 1-x S@CF not only increases the electrochemically active surface area of ​​the catalyst, but also facilitates the release of bubbles generated, resulting in enhanced catalytic activity. For the hydrogen evolution reaction, the Mo 3 S 4 /Co 1-x S@CF electrode exhibits good stability and excellent catalytic activity in 1.0 M KOH (η 10 = 105 mV), 1.0 M PBS (η 10 = 92 mV) and 0.5 M H 2 SO 4 (η 10 = 68 mV) solutions. For the oxygen evolution reaction, the electrode displays excellent stability and catalytic activity in 1.0 M KOH solution (η 10 = 215 mV). When used for overall water splitting in 1.0 M KOH solution, Mo 3 S 4 /Co 1-x S@CF achieves a current density of 10 mA cm−2 at a low potential of 1.58 V and maintains it stably for 40 h. This study presents a simple method for preparing transition metal-based bimetallic composite catalysts for efficient hydrogen production. [ABSTRACT FROM AUTHOR]

A promising approach to resolving insufficient freshwater resources is utilizing solar energy for steam generation. Although various types of photothermal conversion materials have been developed, there are still some obstacles, such as complicated system structure fabrication and low energy utilization, that severely hinder their practical application. Herein, we designed and produced a self-floating porous carbon/polyaniline foam (PCPF) evaporator via impregnating melamine foam with porous carbon generated following the bottom-up pyrolytic method and polyaniline, followed by thermal treatment, for efficient solar steam generation. The PCPF obtained with a porous carbon (PC) to polyaniline (PAN) mass ratio of 3:5 (PCPF-3) exhibited a rich pore structure, good hydrophilicity, low thermal conductivity (0.0413 W m−1 K−1), and excellent light absorption (96.1%). Our results show that, without additional thermal insulators, the evaporation rate of PCPF-3 reached 1.496 kg m−2 h−1, and the photothermal conversion efficiency reached 87.3% under one sun irradiation. Furthermore, it also exhibited good durability and desalination performance. This type of environmentally friendly, low-cost, and stable photothermal conversion material could be used in water treatment and seawater desalination. [ABSTRACT FROM AUTHOR]

In this work, for the first time we are reporting the development of a kind of high rate and long cycle life electrode composed of nickel cobalt manganese ternary carbonate hydroxide (NiCoMn-CH) ultrathin nanoflakes coated on Co-CH nanowire arrays (NWAs), which are directly generated on a nickel foam (NF) support. The hierarchical heterostructures are synthesized via a scalable two step solvothermal strategy without any adscititious surfactant and binder. The smart combination of Co-CH and NiCoMn-CH nanostructures in the nanowire arrays shows significant synergistic effect on the enhancement of the electrochemical performance of the as-fabricated supercapacitors. The as-obtained electrode exhibits excellent conductivity and high specific surface area, resulting in an unprecedented high specific capacitance (up to 3224 F g−1 at 1 A g−1 in a three-electrode system) and an ultralong cycling stability (92.4% retention after 6000 successive charge–discharge cycles 5 A g−1). Meanwhile, an asymmetric supercapacitor device assembled of the Co-CH@NiCoMn-CH hierarchical nanostructures as positive electrode and activated carbon (AC) as negative electrode delivers good energy density of 20.31 W h kg−1 at the power density of 748.46 W kg−1 in the operation window 0–1.5 V. This methodology could be generalized to the design of other novel structured nanomaterials for energy storage devices and other applications. [ABSTRACT FROM AUTHOR]

Trimetallic sulfide microspheres with flower morphology prepared based on novel bimetallic MOF via sequential ion exchange processes exhibit promising energy storage properties. Rational design of electrical active materials with high performance for energy storage and conversion is of great significance. Herein, Cu(NiCo) 2 S 4 /Ni 3 S 4 , a three-dimensional (3D) hierarchical hollow heterostructured electrode material, is designed by etching the well-defined bimetal organic framework (MOF) via sequential in-situ ion-exchange processes. This trimetallic sulfides with unique structure provide large surface area, hierarchical pore distribution and enhanced electrical conductivity, can enrich the active sites for redox reactions, facilitate electrolyte penetration and rapid charge transfer kinetics. As a result, the Cu(NiCo) 2 S 4 /Ni 3 S 4 electrode exhibits a high specific capacitance of 1320 F/g at 1 A/g and excellent rate performance (only 15% of capacitance is attenuated when the current density is increased by 20 times). Furthermore, a fabricated hybrid supercapacitor of Cu(NiCo) 2 S 4 /Ni 3 S 4 /AC can deliver a maximum energy density of 40.8 Wh/kg, remarkable power density of 7859.2 W/kg and superior cycling stability (85% retention of capacitance after 5000 cycles), demonstrating great potential for practical applications in energy storage and conversion devices. [ABSTRACT FROM AUTHOR]

Manganese dioxide (MnO 2) with high theoretical capacity (1380 F g−1), high natural abundance and low cost has been considered as one of the most competitive active materials for preparing the electrode of supercapacitors. However, the poor electrical conductivity limits its broad applications. To solve this problem, we design a hierarchical Cu(OH) 2 @MnO 2 core-shell nanorods array on copper foam (CF), in which the one-dimensional (1D) Cu(OH) 2 nanorod core provides the scaffold for the growth of MnO 2 nanosheets and a short ion and electronic diffusion pathway and the two-dimensional (2D) MnO 2 nanosheets shell provides enormous active sites due to their large surface area. The obtained Cu(OH) 2 @MnO 2 /CF nanorods array displays an excellent areal capacitance of 708.62 mF cm−2 at the current density of 2 mA cm−2 (283.45 F g−1 at 0.8 A g−1). Additionally, the assembled Cu(OH) 2 @MnO 2 /CF//activated carbon (AC) asymmetric supercapacitor shows an outstanding energy density of 18.36 Wh kg−1 at a power density of 750 W kg−1. Two such capacitors connected in series can light up a red LED bulb for over fifteen minutes. [ABSTRACT FROM AUTHOR]

Herein, we designed and prepared nickel metal-organic framework microspheres anchored directly on reduced graphene oxide (Ni-MOF/rGO) by a facile hydrothermal and successive calcining process. The electrode for Ni-MOF/rGO composite annealed at an optimized temperature of 300 °C (Ni-MOF/rGO-300) shows desired conductivity, good cycling stability and high ion-accessible surface area, leading to an ultrahigh specific capacitance of 954 F g−1 at a current density of 1 A g−1 and a remarkable rate capability of 80.25% at 5 A g−1. Meanwhile, the assembled Ni-MOF/rGO-300//activated carbon asymmetric supercapacitor (ASC) shows a favorable energy density up to 17.13 Wh kg−1 at a power density of 750 W kg−1 in the potential window of 0–1.5 V. Moreover, the capacitance retention can still maintain 81.63% after 4000 cycles at a high current density of 5 A g−1. The excellent electrochemical properties can be credited to the synergistic effects between the unique structures of Ni-MOF and rGO, which makes the Ni-MOF/rGO composite a potential electrode material for high performance supercapacitors. [ABSTRACT FROM AUTHOR]

Compressible and flexible supercapacitors have aroused enormous interest of many scientific researchers for potential applications in wearable electronic products. However, the design and construction of the electrode with superior mechanical as well as electrical properties still face a lot of challenges. In present work, melamine foam/polypyrrole (MF/PPy) electrode with high deformation-tolerance and excellent electrochemical performance is prepared by in-situ interfacial polymerization of polypyrrole on commercial melamine foam, where PPy nanoparticles with size of 700 nm are uniformly anchored on the MF skeletons. The electrochemical characterizations show that the electrode exhibits excellent specific area capacitance of 2.685 F cm−2 at 2 mA cm−2 and good cyclic stability with more than 80% of capacitance remained after 3000 cycles. Furthermore, a symmetrical aqueous supercapacitor is assembled and exhibits an excellent energy density up to 75.95 μWh cm−2 at the power density of 5.82 mW cm−2 and excellent cycling stability as the current density increases by 10 times. Even under a high strain of 70%, about 95.76% of the initial capacitance is retained after 500 consecutive compressions. These outstanding performances enable the MF/PPy composite a promising candidate for potential applications in compressible and flexible electrochemical energy storage devices. [ABSTRACT FROM AUTHOR]

Direct generation of active materials on carbon cloth (CC) is regarded as an efficient and convenient means to obtain flexible electrodes with high supercapacitor performance. However, uniform generation of active materials on the both sides of CC remains a great challenge. Herein, a facile hanging-hydrothermal method was used to directly generate uniform NiCo 2 S 4 nanosheet arrays on carbon cloth (NiCo 2 S 4 /CC), which was then utilized as the positive electrode for flexible supercapacitors. Taking advantage of the unique and uniform honeycomb-like structure of NiCo 2 S 4 nanosheets, the obtained NiCo 2 S 4 /CC electrode can deliver an excellent specific capacitance (1638 F g−1 at 1 A g−1), which is significantly higher than NiCo 2 O 4 /CC electrode (657.4 F g−1 at 1 A g−1). A two-electrode flexible supercapacitor was assembled using NiCo 2 S 4 /CC as positive electrode and carbon cloth coated with activated carbon as negative electrode and revealed a high energy density of 25.2 Wh kg−1 at a power density of 799.6 W kg−1, highlighting its great potential for flexible supercapacitor applications. [ABSTRACT FROM AUTHOR]

The hollow and spinous NiCo 2 S 4 nanotubes were designed and prepared through hydrothermal sulfurization reaction using the degummed natural cocoon silk as a template. Recently, ternary cobalt nickel sulfide, performing as the promising electrode material for supercapacitors has obtained great interests. Herein, the hollow and spinous NiCo 2 S 4 nanotubes are designed and prepared through a simple hydrothermal reaction using the natural silk as the template. The spinous Ni-Co precursors are grown on the natural silk through a facile hydrothermal strategy and the hollow structure is obtained by decomposing the silk via hydrothermal sulfurization. After the calcination treatment, the hollow and spinous NiCo 2 S 4 nanotubes are applied as the electrode material and exhibit better electrochemical performance than the solely vulcanized samples. In addition, owing to the unique hollow and spinous structure of NiCo 2 S 4 nanotubes, the supercapacitor electrode material shows good specific capacitance (630 F g−1 at 1 A g−1), low internal resistance R s (0.68 Ω) and high capacitance retention (91% after 3000 cycles) at 10 A g−1. Furthermore, an all-solid-state asymmetric supercapacitor is self-assembled with the SC400 composite and exhibits an energy density of 52.34 Wh kg−1 at the power density of 2206.37 W kg−1. Additionally, a blue LED indicator can be powered by connecting two ASCs in series. The prepared hollow and spinous NiCo 2 S 4 nanotubes with excellent electrochemical properties can envision promising applications in energy storage devices and nanotechnology. [ABSTRACT FROM AUTHOR]