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BACKGROUND: Osteoarthritis is one of the leading causes of global disability and pain. OBJECTIVE: To investigate whether High-Intensity Laser therapy has superior pain-relieving effects in individuals with symptomatic knee osteoarthritis. METHODS: Searches were conducted using CENTRAL, MEDLINE, CINAHL, EMBASE, Web of Science, PEDro, and related reference lists with language limed to English. Clinical trials investigating the effectiveness of High-Intensity Laser therapy compared to other laser therapies, conventional therapies or exercises on knee osteoarthritis pain were included. The screening and selection of studies, data extraction, and methodological quality assessment were performed by two independent researchers. Studies were quantitatively integrated using the Review Manager Software and qualitative analysis using the criteria recommended by the Cochrane Collaboration. RESULTS: Nine studies meeting the eligibility criteria were identified, among which only one study was identified as excellent methodology quality, six was marked as good quality, and the remaining two studies were regarded as fair or poor quality. All studies reported positive effects of High-Intensity Laser therapy on knee osteoarthritis pain. Two studies (136 people) gave indication that there was moderate evidence that High-Intensity Laser therapy could be a promising new possibility in pain relief among patients with knee osteoarthritis compared with sham laser therapy in a short-term treatment (MD, - 2.04, 95% CI, - 2.12 to - 1.96; Z = 51.01, P < 0.01). Four studies (160 people) showed that High-Intensity Laser therapy could be an effective modality on treating pain compared to conventional physiotherapies in decreasing visual analog scale score (MD, - 0.98, 95% CI, - 1.19 to - 0.76; Z = 9.02, P < 0.01). Three studies (123 people) demonstrated that High-Intensity Laser therapy combined with exercises was more effective than placebo laser or lower-intensity laser combined with exercises in alleviating pain in patients with knee osteoarthritis (MD, - 1.54, 95% CI, - 1.84 to - 1.24; Z = 10.06, P < 0.01). CONCLUSION: High-Intensity Laser therapy could be a promising and recommended modality in alleviating knee osteoarthritis pain, especially when it was implemented in combination with exercises. [ABSTRACT FROM AUTHOR]

Prussian blue analogs (PBAs) with unique structure show great potential for aqueous potassium-ion batteries (AKIBs). Herein, K2Co[Fe(CN)6] and KNi[Co(CN)6] architectures are developed as the cathode candidates for AKIBs. Moreover, the reaction kinetics detection and DFT calculations are employed to analyse the battery performances. [ABSTRACT FROM AUTHOR]

Developing non-noble metal-based electrocatalysts with high catalytic activity is an urgent task for overall electrocatalytic water decomposition. In this study, carbon-incorporated porous honeycomb NiCoFe phosphide (labelled NiCoFeP/C) was successfully developed from a metal–organic framework (MOF) precursor for the first time. Benefitting from a unique structure and compositional advantages, NiCoFeP/C exhibits excellent bifunctional electrocatalytic activity for the oxygen evolution reaction/hydrogen evolution reaction (OER/HER) in alkaline solution, showing low OER and HER overpotentials of 270 and 149 mV at 10 mA cm−2, respectively. This work successfully developed a MOF-derived novel multi-component transition metal phosphide with a unique structure, which shed some light on the development of promising catalysts for the OER/HER. [ABSTRACT FROM AUTHOR]

Carbon-incorporated NiO/Co3O4 concave surface microcubes (denoted as NCMC) are successfully developed from a precursor of Ni3[Co(CN)6]2 for the first time. The NCMC exhibits excellent electrocatalytic activity for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) in potassium hydroxide solution, affording a current density of 10 mA cm−2 at 169.5 mV for the HER and 290 mV for the OER, respectively. This communication describes a rational design of MOF-derived mixed metal oxides as electrocatalysts for overall water splitting, promoting the further development of MOF materials in the field of energy conversion. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The ZIF-67-derived hollow CoS shows a high specific capacitance of 720 F g−1. • The anode and cathode of the capacitor are derived from the same precursor. • The surface capacitive contribution is dominated in hollow CoS energy storage. • Assembled capacitor shows a maximum energy density of 80 Wh kg−1. Abstract In this work, hollow CoS nanobox (noted as HCSN) have been successfully synthesized via annealing and hydrothermal process from zeolitic imidazolate framework (ZIF-67) template. When tested as positive electrode materials in alkaline aqueous electrolyte, it shows high specific capacitance of 720 F g−1 at a current density of 1 A g−1, good rate capability (82.1%) and good cycling stability with 86.4% capacitance retention over 10,000 cycles at 10 A g−1. To further demonstrate the advantages of our ZIF-67 derived materials, asymmetric energy storage device was assembled (HCSN//NC), where the as-prepared HCSN was employed as the anode and ZIF-67-derived nanoporous carbon (noted as NC) as the cathode. This device achieves high energy density (80 Wh kg−1 at a specific power density of 882 W kg−1), good rate capability (53.3 Wh kg−1 even at a specific power density of 7.9 kW kg−1) and long-term stability up to 10,000 cycles. More importantly, it could simultaneously light up 12 LEDs in parallel, demonstrating its potential in practical applications. [ABSTRACT FROM AUTHOR]

The well-designed Fe-Co-Ni phosphide centers comprehensively manage the active sites, polysulfide evolution pathways and the ion/electron conductivity, deciphering the synergistic catalytic essence of Fe-Co-Ni phosphide centers for Li–S chemistry. [Display omitted] • Realizing the activity manipulation of trimetallic Fe-Co-Ni phosphides. • Unveiling the synergistic catalysis essence of trimetallic Fe-Co-Ni phosphides. • Combing X-ray 3D nano-CT technique for the multi-level characterizations. Lithium–sulfur batteries (LSBs) have emerged as prospective candidates for energy storage systems due to their high energy density and low cost of sulfur. However, the fast capacity degradation stemming from the fatal lithium polysulfide (LiPS) shuttle and sluggish redox reaction kinetic acts as the bottleneck for the real implementation of LSBs. Herein, we propose a well-designed nanosphere functionalized with trimetallic Fe-Co-Ni phosphides (FCNP) to host sulfur and promote the sulfur redox reactions. The well-dispersed trimetallic phosphides can not only enhance polarity and electron conductivity but also supply sufficient conversion sites and short sulfur evolution pathway. Therefore, the elaborated trimetallic phosphides on carbon nanosphere effectively inhibits LiPSs escaping from the cathode to anode. Further, the systematic electrochemical measurements and synchrotron X-ray three-dimensional nano-computed tomography (X-ray 3D nano-CT) results provide clear evidence that FCNP as a bidirectional electrocatalyst smoothly accelerates the generation and decomposition of Li 2 S. Accordingly, the S/FCNP cathode exhibits a remarkable discharge capacity of 1172.3 mA h g−1 at 0.2C in coin cell, 1164.0 mA h g−1 at 0.1C in pouch cell and the favorable cycling performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple self-template method and simultaneous sulfurization/selenization reaction. • Phase boundaries are favorable to accelerate the kinetic behavior of sodium storage. • A high capacity, rapid reaction kinetics and prominent electrochemical stability. Reasonable design and synthesis of anode materials with high capacity, excellent rate capability and good cycling stability is vital for the pragmatic application of sodium-ion batteries (SIBs). Transition metal chalcogenides possess immense potential on account of their distinguished redox reversibility and high theoretical specific capacity. Herein, the hollow metal sulfide/metal selenide (NiS 2 /NiSe 2) heteroboxes with rich phase boundaries have been manufactured as anode for SIBs. The lattice distortion and charge redistribution at the phase boundary of the as-prepared NiS 2 /NiSe 2 heteroboxes can expose more active sites, which is profitable to the adsorption of Na+ and accelerate the sodium storage kinetics process, and the unique hollow porous structure is conducive to buffering the volume expansion and can facilitate the penetration of electrolyte during the repeated Na+ de-intercalation process. By virtue of these advantages, the NiS 2 /NiSe 2 heteroboxes delivers a good rate capability, where the average capacity at 10 A g-1 in comparison with 0.1 A g-1 is 64.3%. Otherwise, it exhibits an ultralong reversible capacity of 292 mA h g-1 after 2000 cycles at 10 A g-1 with only 0.0125% average capacity decay per cycle. The rational construction of phase boundary with unique structure in this article has guiding significance for the manufacture of progressive SIBs anode materials. [ABSTRACT FROM AUTHOR]

The work function difference (WFD) between the two electrode materials has a positive effect on the potential window for the asymmetric supercapacitors (ASCs) theoretically, but there is no relevant investigation. Here, we use the kelvin probe force microscope to detect contact potential difference (CPD) which can well represent the WFD between carbon@K 0·5 Mn 2 O 4 positive material and four metal oxides anode materials, namely MoO 3 , V 2 O 5 , Fe 2 O 3 and WO 3 respectively. What's more, the relationship between WFD and the potential window is studied by combining contact potential difference with electrochemical testing. We find that the as-fabricated carbon@K 0·5 Mn 2 O 4 //MoO 3 device exhibits the widest potential window of 2.42 V with the maximum WFD. As a result, the carbon@K 0·5 Mn 2 O 4 //MoO 3 have a high energy density of 66.7 Wh kg−1 at the power density of 5.95 kW kg−1. Our study provides a new experimental reference for constructing supercapacitor devices with wide potential window and high energy density. • Reveal the effect of work function difference on the supercapacitors potential window. • Assembled Carbon@K 0·5 Mn 2 O 4 //MoO 3 device exhibits voltage window of 2.42 V. • The device shows energy density of 66.7 Wh kg−1 at the power density of 5.95 kW kg−1. [ABSTRACT FROM AUTHOR]

A simple high-temperature solid state process is developed to prepare MoO 4 2−-doped Na 3 V 2 (PO 4) 3 (NVP-MoO 4 (x), x = 0, 0.05, 0.10, 0.15) with excellent rate capability and long cycling stability. In-situ XRD measurement reveals that the electrochemical reaction of NVP-MoO 4 (0.10) exhibits a highly reversible phase transition process. [Display omitted] • MoO 4 2−-doped Na 3 V 2 (PO 4) 3 is prepared by a simple high temperature solid-state method. • MoO 4 2− doping can propel kinetics behavior and boost electronic conductivity. • The NVP-MoO 4 (0.10) presents a superior rate and excellent cyclic performance. • In-situ XRD reveals that the electrochemical reaction of NVP-MoO 4 (0.10) exhibits a highly reversible phase transition process. Sodium vanadium phosphate [Na 3 V 2 (PO 4) 3 ] with high voltage platform, low cost and environment friendliness has been considered as one of the most promising candidates as cathodes for high-performance sodium-ion batteries. However, the sodium storage property of Na 3 V 2 (PO 4) 3 is limited because of its low electronic conductivity and poor kinetic performance. Herein, MoO 4 2−-doped Na (3+2x) V 2 (PO 4) (3-x) MoO 4(x) [NVP-MoO 4 (x), x = 0, 0.05, 0.10, 0.15] have been developed and prepared by a feasible solid-state reaction. The optimal NVP-MoO 4 (0.10) delivers a high initial capacity of 108.9 mA h g−1 and presents an excellent capacity retention of 91.5% at 1 C after 150 cycles. In addition, the NVP-MoO 4 (0.10) shows a good rate capability, delivering a relatively high capacity of 84.2 mA h g−1 at 50 C. The results of sodium storage measurement and density of states calculation indicate that MoO 4 2− doping can significantly enhance the structural stability, promote the kinetics behavior and boost the electronic conductivity of the materials. In-situ XRD test reveals that the electrochemical reaction of the NVP-MoO 4 (0.10) exhibits a highly reversible phase transition process. This work provides a new insight for the design of advanced cathodes for high-performance sodium-ion batteries by the strategy of unique anion doping. [ABSTRACT FROM AUTHOR]

Using an environmentally friendly method to produce a stable and highly catalytically active electrocatalyst for the oxygen evolution reaction (OER) is becoming increasingly urgent. Herein, a novel bimetallic metal–organic framework (MOF), specifically a copper–cobalt 1, 3, 5-benzenetricarboxylate (Cu–Co-BTC) MOF, was successfully prepared by employing the gas–solid two-phase flow (GSF) synthetic technique. The as-prepared Cu–Co-BTC with its multiple active sites afforded a current density of 10 mA cm−2 at 239 mV for the OER in a 1 mol L−1 KOH solution, and showed a better electrocatalytic performance than did single-metal-containing Cu-BTC and Co-BTC materials. This work provides a new idea, one involving using novel gas–solid phase reactions for the preparation of electrocatalysts in large quantities. [ABSTRACT FROM AUTHOR]

Objective: There are several meta-analyses of randomized controlled trials (RCTs) demonstrating the benefits of virtual reality (VR) training as an intervention for motor performance, activity of daily living (ADL) and quality of life (QoL) outcomes in patients with Parkinson's disease (PD). However, the aggregate evidence collected to date has not been thoroughly evaluated for strength, quality, and reproducibility. An umbrella review from published meta-analyses of RCTs was conducted to evaluate the strength and quality of existing evidence regarding the efficacy of VR training in improving the motor performance, ADL and QoL outcomes of patients with PD. Methods: PubMed, PsychInfo, Web of Science, and Scopus were searched to identify relevant meta-analysis of RCTs examining the effects of VR training on motor performance and quality of life outcomes in PD patients. We recalculated the effect sizes (Hedges'g) for VR training using DerSimonian and Laird (DL) random effects models. We further assessed between-study heterogeneity, prediction interval (PI), publication bias, small-size studies, and whether the results of the observed positive studies were better than would be expected by chance. Based on these calculations, the quality of evidence for each outcome was assessed by using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) criteria. Results: Four meta-analysis with eight outcomes included in the umbrella review was recalculated effect size. Pooled results found VR training can large improve the basic balance ability, moderate improve the overall balance capacity and moderate improve the stride length in PD patients. For ADL and QoL, the effect sizes were pooled that suggested VR training can moderate improve ADL and QoL for PD patients. However, no statistically clear evidence was found in walking speed, motor function and gait function during VR training. The analyzed meta-analyses showed low-to-moderate methodological quality (AMSTAR2) as well as presented evidence of moderate-to-very low quality (GRADE). Tow adverse reactions were reported in the included meta-analyses. Conclusions: In this umbrella review, a beneficial correlation between VR and balance ability, stride length, ADL and QoL in PD patients was discovered, especially for the very positive effect of VR on balance because of two of the eight outcomes related to balance ability showed large effect size. The observations were accompanied by moderate- to very low-quality rating evidence, supporting VR training as a practical approach to rehabilitation. [ABSTRACT FROM AUTHOR]

The gradient temperature was manipulated to construct hollow irregular carbon spheres with regulated intrinsic defects and surface area targeting favorable potassium storage. An enlarged surface area, increased intrinsic defects, and superior conductivity induced more surface-active interfaces. These actions facilitated a high reversible capacity as well as excellent cycling stability. [ABSTRACT FROM AUTHOR]

Nickel–cobalt Prussian blue analogues (Ni–Co PBAs) suffer from structural instability in neural and alkaline electrolytes due to the dissolution of metal cations and cyanide anions caused by external H2O attack, resulting in capacity degradation and restricted life span. Herein, in this work, Ni–Co PBA quantum dots embedded in N-doped carbon (CC-Ni–Co PBA) were synthesized via a facile coprecipitation method and in situ polymerization followed by calcination under a nitrogen atmosphere. The obtained electrode provided a high specific capacity of 333.7 C g−1 and still retained 188.8 C g−1 when the current density increased by 40 times. Remarkably, it exhibited outstanding cycling stability with 82% retention of capacity after 10 000 cycles in an aqueous alkaline electrolyte, which benefited from the inner Ni–Co PBA quantum dots that provided a surrounding space and significantly accommodated the volume change during the repeated charge–discharge process, and the outer carbon layer that served as a protective barrier to hinder the Ni–Co PBA from dissolving into the electrolyte, thus realizing the durability of the electrode. Furthermore, an asymmetric alkaline battery device was assembled which achieved a maximum energy density of 33.2 W h kg−1 and a power density of 3.1 kW kg−1. Our work contributed to the development of PBA-based electrode materials with improved cycling stability as battery-type electrodes in aqueous electrolytes. [ABSTRACT FROM AUTHOR]

• The accelerated kinetic mechanism of NiSe 2 /FeSe 2 heterointerface was investigated. • The spatial carbon dual-confined structures were constructed successfully. • The as-prepared NFS@NC@C exhibits ultra-low capacity degradation rate of 0.021 % per cycle after 1200 cycles at 5 A/g. • The potassium storage reaction mechanism of NFS@NC@C was explored by using ex/in-situ investigations. Potassium-ion batteries (PIBs) have received increased attention for grid-scale energy storage applications; however, their practical development is still hindered by the lack of advanced anode materials to overcome the slow kinetics and huge volume expansion. Herein, a multi-interface engineered iron-nickel bimetallic selenide (NiSe 2 /FeSe 2 , NFS) space-confined in a dual-carbon structure is designed as an efficient anode for PIBs. The NFS heterostructure with different band structures endows a built-in electric field, which facilitates fast interfacial electron transport and reduced ionic diffusion resistance. Moreover, the NC@C matrix further accelerates the charge carrier transport dynamics of NFS while suppressing the huge volume change to ensure good cycling performance. Consequently, the as-prepared NFS@NC@C exhibits a high initial specific capacity of 349.6 mA h g−1 at 0.1 A/g, good rate capability, and ultra-low capacity degradation rate of 0.021 % per cycle after 1200 cycles at 5 A/g. Further ex/in-situ investigations and theoretical calculations unveil the K+ storage mechanism of NFS@NC@C, which involves a phase conversion reaction for K+-ions migration with a low diffusion energy barrier. This work heralds the prospect of space-confined multi-heterointerface design for high-performance PIBs electrode materials. [ABSTRACT FROM AUTHOR]

Hierarchical nickel and cobalt inorganic–organic nanostructures on carbon fiber paper have been fabricated by a one-step hydrothermal approach directed by hexamethylenetetramine (HMT). The morphology and evolution of these single-crystalline inorganic–organic nanosheets–nanowires (IOSW) are investigated. Results show that HMT plays a vital role in the secondary growth of single-crystalline nanowires. Besides, HMT molecules intercalate within the interlayers of inorganic materials, forming single-crystalline organo-LDH (layered double hydroxide) nanosheets and organo-carbonate hydroxide nanowires. Furthermore, the electrode is employed for battery-like energy storage applications. The interconnected nanosheet–nanowire structure affords rich open spaces and efficient passways for ion diffusion and electron transport. A specific capacitance of 1308 F g−1 (1.7 F cm−2, at the current density of 4 mA cm−2) and excellent long-term cycling performance (94% retention after 10 000 cycles) are achieved. The high stability of the electrode could be attributed to the interactions between HMT and nickel/cobalt within the interlayer. In addition, a two-electrode device consisting of nickel and cobalt IOSW as the positive electrode and commercial active carbon as the negative electrode is fabricated and reaches a maximum energy density of 32.3 W h kg−1 (8 A g−1). [ABSTRACT FROM AUTHOR]

The Co2+-doped NiAl-LDH (NiAl-LDH-Co2+- x , x = 0, 0.3, 0.6, 0.9, 1.2, 1.5) nanoflower electrodes with extended layer spacing and electronic modulation are prepared by one-step hydrothermal method for high performance supercapacitors. [Display omitted] Layered double hydroxides (LDHs) with high theoretical capacity have broad prospects in energy storage applications. However, their slow charge transfer kinetics and easy agglomerate hinder their applications in high-performance supercapacitors. Herein, Co2+-doped nickel aluminum layered double hydroxides (NiAl-LDH-Co2+- x , x = 0, 0.3, 0.6, 0.9, 1.2, 1.5) have been designed and prepared by a convenient hydrothermal process. The multicomponent layer structure formed by cobalt doping facilitates sufficient penetration of the electrolyte and accelerates the charge transfer kinetics. Furthermore, the more open layer spacing and electronic interactions induced by Co2+ doping are conducive to accelerating ion de-intercalation, thereby further improving the kinetic behavior of charge storage. Benefiting from the unique microstructure and Co2+ doping effect, the prepared NiAl-LDH-Co2+-0.9 provides a superior specific capacity of 985 C g-1 at 1 A g-1. In addition, the assembled hybrid supercapacitor with the NiAl-LDH-Co2+-0.9 as the positive electrode provides a remarkable energy density of 22.51 Wh kg−1 at a power density of 800 W kg−1 and exhibits an excellent cycle life with 80 % capacity retention after 20,000 cycles. This study demonstrates the great potential of efficient microstructure design and doping strategy in enhancing the charge storage of electrode materials. [ABSTRACT FROM AUTHOR]

The Co2+-doped NiAl-LDH (NiAl-LDH-Co2+- x , x = 0, 0.3, 0.6, 0.9, 1.2, 1.5) nanoflower electrodes with extended layer spacing and electronic modulation are prepared by one-step hydrothermal method for high performance supercapacitors. [Display omitted] Layered double hydroxides (LDHs) with high theoretical capacity have broad prospects in energy storage applications. However, their slow charge transfer kinetics and easy agglomerate hinder their applications in high-performance supercapacitors. Herein, Co2+-doped nickel aluminum layered double hydroxides (NiAl-LDH-Co2+- x , x = 0, 0.3, 0.6, 0.9, 1.2, 1.5) have been designed and prepared by a convenient hydrothermal process. The multicomponent layer structure formed by cobalt doping facilitates sufficient penetration of the electrolyte and accelerates the charge transfer kinetics. Furthermore, the more open layer spacing and electronic interactions induced by Co2+ doping are conducive to accelerating ion de-intercalation, thereby further improving the kinetic behavior of charge storage. Benefiting from the unique microstructure and Co2+ doping effect, the prepared NiAl-LDH-Co2+-0.9 provides a superior specific capacity of 985 C g-1 at 1 A g-1. In addition, the assembled hybrid supercapacitor with the NiAl-LDH-Co2+-0.9 as the positive electrode provides a remarkable energy density of 22.51 Wh kg−1 at a power density of 800 W kg−1 and exhibits an excellent cycle life with 80 % capacity retention after 20,000 cycles. This study demonstrates the great potential of efficient microstructure design and doping strategy in enhancing the charge storage of electrode materials. [ABSTRACT FROM AUTHOR]

Si‐based anode electrodes stand out for its excellent capacity among the numerous anode electrodes for lithium‐ion batteries. However, there is still a problem that the volume expansion from the alloying reaction of Li and Si often leads to structural collapse and rapidly capacity degradation. Here, Si nanoparticles (Si NPs) are coated via metal‐organic frameworks (MOFs) derived skeleton to buffer its volume expansion, thereby improving electrochemical properties. Scanning electron microscopy was applied to revealed morphology and structure of the composite material. The results demonstrate that the structure of the prepared composite is Si NPs encapsulated in the unique carbon skeleton. The as‐prepared Si@MIL‐125‐500 exhibits excellent electrochemical performances with an excellent reversible capacity of 304.3 mAh g−1 at 5 A g−1 even after 400 cycles. In addition, the initial coulombic efficiency (ICE) reached up to 86 %. The improved electrochemical performance could be attributed to the distinctive structure of the carbon coated Si NPs and stable titanium(IV) center site, which has improved the electrical conductivity and cycling stability of Si NPs. Moreover, the empty space inside the MOF's carbon skeleton can release the volume strain of Si during electrochemical process. There is an improvement of electrochemical properties for LIBs due to Si NPs restricted in MIL‐125. [ABSTRACT FROM AUTHOR]

• Mg2+ and Mn2+ co-doped Na 3 V 2 (PO 4) 3 is prepared via a simple high temperature solid method. • Mg2+ and Mn2+ co-doping can propel kinetics behavior and enhance electronic conductivity. • The NVP-(MM) 0.01 exhibits an outstanding rate and cycling performance. • Ex-situ XRD revealed that the structure of NVP-(MM) 0.01 is well maintained after 500 cycles at 10 C. In this article, Mg2+ and Mn2+ co-doped Na 3 V 2 (PO 4) 3 cathode material is prepared, which exhibits enhanced rate capability and long-term cyclic stability for sodium-ion batteries. [Display omitted] Na 3 V 2 (PO 4) 3 with open 3D framework structure is perceived as the most potential cathode material for sodium-ion batteries (SIBs). Nevertheless, its electrochemical properties are generally restricted by the larger radius of Na+ and the intrinsic poor electrical conductivity. Herein, we adopt a unique bimetallic doping strategy to prepare Mg2+ and Mn2+ co-doped Na 3 V 2−x (Mg 0.5 Mn 0.5) x (PO 4) 3 [NVP-(MM) x (x = 0, 0.01, 0.02)] through a high temperature solid state reaction. The as-prepared NVP-(MM) 0.01 presents a high initial discharge capacity of 107.7 mA h g−1 at 1 C. Furthermore, NVP-(MM) 0.01 displays a highly rate capability (75.5 mA h g−1 at 15 C) and excellent cycling performance (71 mA h g−1 after 1000 cycles at 20 C). Electrochemical results exhibit that Mg2+ and Mn2+ co-doped with appropriate proportion can enhance the electronic conductivity and sodium storage kinetics process of Na 3 V 2 (PO 4) 3 effectively. Our work provides a novel idea to construct high performance SIBs via a bimetallic co-doped strategy. [ABSTRACT FROM AUTHOR]

It is an inevitable choice to find efficient and economically-friendly electrocatalysts to reduce the high overpotential of oxygen evolution reaction (OER), which is the key to improve the energy conversion efficiency of water splitting. Herein, we synthesized Cu 2 S/Ni 3 S 2 catalysts on nickel foam (NF) with different molar ratios of Ni/Cu by a simple two-step hydrothermal method. Cu 2 S/Ni 3 S 2 -0.5@NF (CS/NS-0.5@NF) effectively reduces the overpotential of OER, displaying small overpotentials (237 mV@100 mA cm−2 and 280 mV@500 mA cm−2) in an alkaline solution, along with a low Tafel slope of 44 mV dec−1. CS/NS-0.5@NF also presents an excellent durability at a relatively high current density of 100 mA cm−2 for 100 h. The excellent performance is benefited by the prominent structural advantages and desirable compositions. The nanosheet has a high electrochemical active surface area and the porous structure is conducive to electrolyte penetration and product release. This work provides an economically-friendly Cu-based sulfide catalyst for effective electrosynthesis of OER. • We synthesized Cu 2 S/Ni 3 S 2 porous nanosheets by a two-steps hydrothermal method. • The nanosheet structure beneficial to exposing more electrochemical active sites. • The Cu 2 S/Ni 3 S 2 possesses competitive OER performance under ambient conditions. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) with high theoretical specific capacity have been considered as one of the most promising candidates for high-performance supercapacitors. However, the low electronic conductivity and insufficient active sites hinder the further large-scale application of bulk LDHs. Here, we successfully synthesized heterostructured Co–Zn LDH@Co(H2PO4)2 nanoflowers by a simple hydrothermal method. As the amount of Co(H2PO4)2 in the whole heterostructure increases, the nanosheets steadily evolve into nanoflowers with a high surface area, providing more electrochemically active sites. Moreover, the built-in electric field formed between Co–Zn LDH and Co(H2PO4)2 improves the conductivity of the composite electrode. As a result, the as-prepared Co–Zn LDH@Co(H2PO4)2 shows a high specific capacity of 919 C g−1 at a current density of 1 A g−1. A hybrid supercapacitor (HSC) with activated carbon (AC) as the negative electrode and Co–Zn LDH@Co(H2PO4)2 as the positive electrode delivers an energy density of 30.4 W h kg−1 at a power density of 400 W kg−1, and 95.3% of the initial capacity is retained after 5000 cycles. This study provides a novel synthesis strategy for constructing heterojunctions to enhance the energy storage properties of LDH-based materials. [ABSTRACT FROM AUTHOR]

Eelectrochemical performance of fabricated asymmetric supercapacitor. Transition metal dichalcogenides (TMDs) have been considered as the promising energy storage materials due to their unique crystalline structure. In this work, the VSe 2 nanoparticles are vertically anchored on N -doping carbon (NC) hollow nanosphere (VSe 2 @NC) for aqueous energy application. The electrochemical measurements indicate that the VSe 2 @NC electrode exhibits outstanding electrochemical properties with high specific capacitance and excellent cycling life. Moreover, the asymmetric supercapacitor was assembled by using VSe 2 @NC cathode and activated carbon anode. It shows high energy density of 85.41 Wh Kg−1 at a power density of 701.99 W Kg−1, and high-stable cycling performance of 90% retention after 2000 cycles. The superior properties are attributed to the particular hollow structure design, which accommodates both the high specific capacity of VSe 2 and the desired electrical conductivity of N -doping carbon sphere template. [ABSTRACT FROM AUTHOR]

Carbonaceous materials are attractive supercapacitor electrode materials due to their high electronic conductivity, large specific surface area, and low cost. Here, a unique hierarchical porous N,O,S‐enriched carbon foam (KNOSC) with high level of structural complexity for supercapacitors is reported. It is fabricated via a combination of a soft‐template method, freeze‐drying, and chemical etching. The carbon foam is a macroporous structure containing a network of mesoporous channels filled with micropores. It has an extremely large specific surface area of 2685 m2 g−1. The pore engineered carbon structure is also uniformly doped with N, O, and S. The KNOSC electrode achieves an outstanding capacitance of 402.5 F g−1 at 1 A g−1 and superior rate capability of 308.5 F g−1 at 100 A g−1. The KNOSC exhibits a Bode frequency at the phase angle of −45° of 18.5 Hz, which corresponds to a time constant of 0.054 s only. A symmetric supercapacitor device using KNOSC as electrodes can be charged/discharged within 1.52 s to deliver a specific energy density of 15.2 W h kg−1 at a power density of 36 kW kg−1. These results suggest that the pore and heteroatom engineered structures are promising electrode materials for ultrafast charging. [ABSTRACT FROM AUTHOR]

Shape-controlled synthesis of non-noble metal nanocrystals (NCs) is vital to their catalysis applications due to their different exposed surfaces and atomic coordination environments. Here, we report a facile synthesis of Ni nanocubes and cuboctahedra with controlled shapes and high yields via a wet-chemistry strategy. The key to success relies on the use of cetyltrimethyl ammonium bromide (CTAB), formaldehyde (HCHO) and a specific reaction temperature, which could effectively cap the desired surface and tune their growth rate. Specifically, nanocubes switched to cuboctahedra and octahedra with an increased reaction temperature due to gradual CO desorption from the surfaces of NCs. Meanwhile, it should be worth noting that CTAB and the generated CO molecules through HCHO decomposition would co-adsorb on the {100} facets of Ni NCs. As a proof-of-application, the obtained Ni NCs exhibited high activity in the oxygen evolution reaction (OER) with over-potentials of 383 mV and 402 mV for nanocubes and cuboctahedra at a current density of 10 mA cm−2, respectively, demonstrating that the {100} facets are more favorable toward OER. These results suggested that their performance is strongly shape dependent and is derived from different surface energies and active sites. [ABSTRACT FROM AUTHOR]

Pseudocapacitors are promising energy storage devices combining the merit of fast charging ability and high energy density. Constructing electrode materials for pseudocapacitors with two-dimensional (2D) materials has become a trending topic. However, it is still a challenge to address the restacking propensity of the 2D materials and to broaden the operational potential window of pseudocapacitors. We herein demonstrate a facile hydrothermal reaction of synthesizing a three-dimensional V 2 O 3 tubes (assembled with ultrathin nanosheets) coated with MoS 2 nanosheets and explore their electrochemical properties for pseudocapacitors. The V 2 O 3 tubes prevent the restacking of MoS 2 nanosheets and serve as conductive scaffold for fast electron transport. Owing to the multi-valence of both Mo and V, the potential window of composite is able to straddle between negative and positive potentials. Therefore, the V 2 O 3 @MoS 2 composite electrode exhibits a broad operational potential range between −1.0 V and +1.0 V, and a high reversible capacitance of 655 F g −1  at 20 mV s −1 . Moreover, an asymmetric pseudocapacitor with our composite as a positive electrode achieves a high specific capacitance (108.7 F g −1  at 0.5 A g −1 ), high energy density (31.8 W h kg -1 ) and excellent cycling stability (no capacitance decay after 35000 cycles). [ABSTRACT FROM AUTHOR]

Architecturally assembling primary building blocks into the expected geometric heterostructure is a tremendous challenge due to the interfaces dislocation and stretch resulting from the lattice-mismatch between heterogeneous building blocks. Although different dimensional nanomaterials have been synthesized, the branched acanthosphere-like hierarchical architecture is needed to be developed and the growth mechanism should be investigated. Here we design and fabricate an acanthosphere-like NiCo 2 O 4 @α-MnO 2 heterostructures architecture by an “in situ growth” technique of two-steps hydrothermal method. The as-prepared acanthosphere-like NiCo 2 O 4 @α-MnO 2 microspheres (denoted as AM-NCM) have a diameter of 5 ∼ 7 um with a highly open and interstitial three dimensional (3D) architecture formed by α-MnO 2 ultrathin nanosheets leading to faster ion diffusion and improved charge transfer kinetics. Therefore, the hybrid electrodes exhibits exceptional specific capacitances of 695 F g −1 (2.17 F cm −2 ) at the current densities of 3.2 A g −1 (10 mA cm −2 ) and good cycling electrochemical stability with only 2.4% capacitance loss after 1000 cycles and still maintains 92% of its initial value after 6000 cycles. The outstanding performance of the branched AM-NCM reveals its potential to be a promising material for energy storage, and also inspires continued research on the formation of branched hierarchical architecture as energy storage materials. [ABSTRACT FROM AUTHOR]

Background: It is a challenge to reduce the muscular discoordination in the paretic upper limb after stroke in the traditional rehabilitation programs.Method: In this study, a neuromuscular electrical stimulation (NMES) and robot hybrid system was developed for multi-joint coordinated upper limb physical training. The system could assist the elbow, wrist and fingers to conduct arm reaching out, hand opening/grasping and arm withdrawing by tracking an indicative moving cursor on the screen of a computer, with the support from the joint motors and electrical stimulations on target muscles, under the voluntary intention control by electromyography (EMG). Subjects with chronic stroke (n = 11) were recruited for the investigation on the assistive capability of the NMES-robot and the evaluation of the rehabilitation effectiveness through a 20-session device assisted upper limb training.Results: In the evaluation, the movement accuracy measured by the root mean squared error (RMSE) during the tracking was significantly improved with the support from both the robot and NMES, in comparison with those without the assistance from the system (P < 0.05). The intra-joint and inter-joint muscular co-contractions measured by EMG were significantly released when the NMES was applied to the agonist muscles in the different phases of the limb motion (P < 0.05). After the physical training, significant improvements (P < 0.05) were captured by the clinical scores, i.e., Modified Ashworth Score (MAS, the elbow and the wrist), Fugl-Meyer Assessment (FMA), Action Research Arm Test (ARAT), and Wolf Motor Function Test (WMFT).Conclusions: The EMG-driven NMES-robotic system could improve the muscular coordination at the elbow, wrist and fingers.Trial Registration: ClinicalTrials.gov. NCT02117089 ; date of registration: April 10, 2014. [ABSTRACT FROM AUTHOR]

Herein, the N-anion and Fe-cation co-doping synergistically modulate the microelectronic structure of the catalyst and exhibits splendid stability under high current density (≥100 h under 1000 mA cm−2). [Display omitted] • Tremella-like dual-doped nickel phosphides are fabricated for the first time. • The microelectronic structure of the catalyst is modulated by co-doping. • The catalyst exhibits a splendid stability for over 120 h at high current density. • The computational results confirm that co-doping optimizes adsorption free energy. Designing high-active earth-abundant electrocatalysts for oxygen evolution reaction (OER) is still a challenge. Elemental doping is an essential strategy to improve catalyst activity. Recent studies have shown that appropriate anion-cation-dual doping could greatly promote performance enhancement of OER electrocatalyst due to the synergistic effect of different dopants. Herein, tremella-like N/Fe dual doping nickel phosphides (N/Fe-Ni 2 P/Ni 12 P 5) are fabricated for the first time. The N-anion and Fe-cation co-doping synergistically modulate the electronic structure, surface states and microtopography of the sample. The electrochemical surface area and electronic conductivity of the N/Fe-Ni 2 P/Ni 12 P 5 are thus greatly enhanced. In addition, the computational simulations demonstrate that anion-cation co-doping optimizes adsorption free energy towards oxygen-containing intermediates and thus enhances intrinsic electrocatalytic activity. Consequently, the as-prepared N/Fe-Ni 2 P/Ni 12 P 5 exhibits splendid OER performances with a low overpotential of 217 mV at the current density of 10 mA cm−2 and an ultra-long durability for over 120 h at high current densities of 500 and 1000 mA cm−2 in 1 M KOH. This work proposes an effective strategy to prepare dual-doped-type phosphide OER electrocatalyst with the promising application potential for large-scale water splitting. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu 39 S 28 , CoS 2 and ZnS are uniformly embedded in the porous N-rich carbon. • Multi-shell structure buffers volumetric stress and increases anode utilization. • Carbon coating and N doping enhance stability and reaction kinetics of anode. Transition metal sulfides (TMSs) have been considered as one type of promising anode materials for sodium-ion batteries (SIBs) due to their high theoretical capacity and outstanding redox reversibility. However, the application of TMSs for SIB anode still faces the fatal challenge mainly pertaining to rapid capacity decay and slow reaction kinetics. Herein, we employ Cu/Zn co-doped ZIF-67 (Cu/Zn-ZIF-67) as the precursor to prepare multi-shell hollow carbon-coated Cu 39 S 28 -CoS 2 -ZnS@nitrogen doped carbon cubes (CCZS@NC@C-15), where the outer shell is a carbon coating layer, and the interior is the double shells formed by Cu 39 S 28 , CoS 2 and ZnS in a porous nitrogen-rich carbon matrix. The as-prepared CCZS@NC@C-15 with unique multi-shell structure can not only effectively buffer the volumetric stress during the sodium insertion/extraction processes, but also increase the volume utilization rate of anode materials. Additionally, the porous carbon cube structure not only increases the contact area between the anode materials and the electrolyte but also prevent the agglomeration of active particles effectively. Furthermore, the carbon coating layer combine with the internal N-rich carbon matrix increases the conductivity of anode and improve the electrochemical stability. As a result, the as-prepared CCZS@NC@C-15 anode shows the remarkable electrochemical stability and rate capability. Our research provides a new strategy for the rational design of TMSs with unique structure for high-performance SIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Split-layer 1D-on-2D h-WO 3 /ort-WO 3 ·0.33H 2 O heterophase structure is firstly prepared. • Oxygen vacancies in heterophase structures activate new proton transport channels. • The ratio of surface- and intercalation-pseudocapacitance of WO 3 can be adjusted. • The WO 3 electrode under high mass loading shows excellent rate performance. • The failure mechanism of WO 3 heterophase structure is experimentally revealed. Intercalation-pseudocapacitance materials are attracting increasing interest as promising electrodes for use in high-capacitance supercapacitors. However, these materials typically exhibit unsatisfactory rate performances due to their relatively slow cation-insertion process. Under high mass loading, their rate performances are even further degraded. Herein is presented our fabrication of an oxygen vacancy-rich h-WO 3 /ort-WO 3 ·0.33H 2 O heterophase structure (HOHS) by a facile hydrothermal synthesis. The HOHS has a split-level nanotubes-on-nanoplates morphology and its formation and energy-storage mechanisms are discussed in detail. The HOHS exhibits a collaborative charge-storage mechanism involving surface redox and proton intercalation, and the capacitance contribution associated with the proton intercalation can be regulated over a wide range. By achieving a trade-off between the surface-limited pseudocapacitance and intercalation-limited behaviours and regulating its morphology, the HOHS electrode with an ultra-high mass loading of 10.8 mg cm−2 delivers a high areal capacitance of 2552 mF cm−2 at 1 mA cm−2 and excellent long-term stability. More importantly, the rate performance of the HOHS (78% capacitance retention at 20 mA cm−2 in comparison to 1 mA cm−2) is better than those reported for WO 3 -based materials. This strategy opens avenues for the fundamental study of the regulation of the energy storage mechanism and the achievement of a trade-off between the capacitance and rate capability in high-mass-loading electrodes. [ABSTRACT FROM AUTHOR]

• A simple method with preparing the core-shell ZnO/CoO@NiCoS nanoarray with double-layer heterojunction. • The coating of NiCoS and the ZnO/CoO heterojunction nanowires can greatly improve the energy storage capacity of electrodes. • This study provides a novel strategy for the preparation of low-cost, deep-discharge electrodes for supercapacitors. A simple method with preparing the core-shell ZnO/CoO@NiCoS nanoarray with double-layer heterojunction for high-performance supercapacitor. [Display omitted] Hybrid supercapacitors (HSC) with high power density and long cycle life are received more attention in the field of energy storage devices, however, the wide application of HSC is limited by the low energy density owing to the insufficient active sites and poor electronic conductivity of electrode materials. Here, we successfully synthesize the ZnO/CoO@NiCoS nanohybrids with double-layer heterojunction by a three-step method. The conductivity of the as-prepared electrode can be improved by the built-in electric field formed between ZnO and CoO. The coating of amorphous NiCoS can provide sufficient active sites and strengthen the physical/chemical stability of ZnO/CoO nanowires. The obtained ZnO/CoO@NiCoS delivers a high specific capacity of 934 C g−1 (1868 F g−1), which is 5.5 times the pristine ZnO electrode. Furthermore, a HSC with ZnO/CoO@NiCoS shows an improved power density (3987.7 W kg−1), a high energy density of 39.2 Wh kg−1, and an excellent cycling stability (initial capacity retention rate of 81.7% after 6,000 cycles). This study not only proposes an effective strategy for the preparation of low-cost, deep-discharge electrodes for supercapacitors, but also provides a novel method to construct nanomaterials with double-layer heterostructure and built-in electric field. [ABSTRACT FROM AUTHOR]

• The Co 3 O 4 is modified by deposition CoNiS nanowires. • CoNiS improves the chemical stability and electrical conductivity of Co 3 O 4. • Co 3 O 4 @CoNiS exhibits high specific capacity. • Core-shell structure provides more active sites and stable structure. • Co 3 O 4 @CoNiS//NOPC supercapacitor delivers an outstanding cyclic stability. Tricobalt tetroxide (Co 3 O 4) with high theoretical capacity has been considered as a promising material for supercapacitors. However, the poor electrical conductivity and poor capacity retention hinder its further larger-scale application. Besides, a series of metal sulfides shows good thermal stability, mechanical stability and electrical conductivity. Here, hierarchical core-shell nanostructure is successfully synthesized by coating the Co 3 O 4 nanowires with highly conductive CoNiS (Co 3 O 4 @CoNiS) by a facile two-step method of hydrothermal treatment and succeeding electrodeposition. And the core-shell structure presents high electrical conductivity, discharge capacity and good cycle life. The as-prepared Co 3 O 4 @CoNiS exhibited a high specific capacity of 1153.75 C g−1, which is 1.97 times as much as that of Co 3 O 4. Furthermore, an asymmetric supercapacitor (ASC) was assembled by using the N/O co-doped porous carbon (NOPC) as negative electrode and the as-prepared Co 3 O 4 @CoNiS as positive electrode, which showed a high energy density of 46.95 Wh kg−1 at the power density of 400 W kg−1 and an ultra-stable capacity retention with 95.6% for 20,000 cycles. The cyclic stability of similar work is lower than that of our work, which provides a reference for the preparation of electrode materials with long-term cyclic stability. [ABSTRACT FROM AUTHOR]

As a key building block to power flexible electronics, there is need for the development of flexible current collectors. Bombyx mori silk, a traditional textile, attracts increasing attention for its potential application in flexible electronics and is a promising raw material for flexible carbon electrodes in current collector fabrication. In this work, molybdenum dioxide nanoparticles (MoO 2 NPs), which possess chemical stability and high mass specific capacitance, was used as a feed additive and combined with mulberry leaves to raise silkworms. It was found that the MoO 2 NPs were embedded within the silk fibers, which endowed the resulting silk with favorable features for electrochemical energy storage in flexible electronics. After carbonization, the specific capacitance of electrodes prepared with silk from the MoO 2 NPs feeding group, with a mass/volume ratio of 5 g/L, was enhanced from 100 F/g to 245 F/g at a current density of 0.2 A/g. Impressively, the electrodes show high coulombic efficiency with excellent stability. This work demonstrates the possibility of producing carbonized silk with superior properties for developing silk-based flexible electrodes for use in energy storage devices in a large-scale, green, low-cost way. Unlabelled Image • A green and effective way to gain carbonized silk with better electrochemical characteristics at a large scale was presented. • The mechanical properties of the resulted silk were enhanced after feeding silkworms with MoO 2 nanoparticles. • It's the first time to observe the nanoparticles encapsulated within the silk directly via in situ functionalization. • The MoO 2 nanoparticles fed to silkworms retain the nanoscale dimensions and original structures after spinning. • Our study broadened the potential contribution of the carbonized silk to the development of soft electronics. [ABSTRACT FROM AUTHOR]

Background: The aim of this study is to investigate quantitative outcome measurements of hand motor performance for subjects after mild to moderate stroke using grip control tasks and characterize abnormal flexion synergy of upper extremities after stroke.Methods: A customized dynamometer with force sensors was used to measure grip force and calculate rotation torque during the sub-maximal grip control tasks. The paretic and nonpartic sides of eleven subjects after stroke and the dominant sides of ten healthy persons were tested. Their maximal voluntary grip force was measured and used to set sub-maximal grip control tasks at three different target force levels. Force control ability was characterized by the maximal grip force, mean force percentage, coefficient of variation (CV), target deviation ratio (TDR), and rotation torque ratio (RTR). The motor impairments of subjects after stroke were also evaluated using the Fugl-Meyer assessment for upper extremity (FMA-UE) and Wolf Motor Function Test (WMFT).Results: Maximal grip force of the paretic side was significantly reduced as compared to the nonparetic side and the healthy group, while the difference of maximal grip force between the nonparetic side and the healthy group was not significant. TDR and RTR increased for all three groups with increasing target force level. There were significant differences of CV, TDR and RTR between the paretic side and the healthy group at all the force levels. CV, TDR and RTR showed significant negative correlations with FMA-UE and WMFT at 50% of maximum grip force.Conclusions: This study designed a customized dynamometer together with an innovative measurement, RTR, to investigate the hand motor performance of subjects after mild to moderate stroke during force control tasks. And stroke-induced abnormal flexion synergy of wrist and finger muscles could be characterized by RTR. This study also identified a set of kinetic parameters which can be applied to quantitatively assess the hand motor function of subjects after mild to moderate stroke. [ABSTRACT FROM AUTHOR]