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Aqueous rechargeable zinc ion batteries (ZIBs) are regarded as a promising candidates for next-generation energy storage devices but strongly hindered by the limited utilization of the zinc metal anode (below 5%) due to the active water/anion corrosion. Herein, an ion selective and water-resistant cellulose nanofiber (CNF)/MXene composite membrane has been developed through molecular sieving to restrict active water and anions from the electrode/electrolyte interface through dehydration of zinc ions, avoiding the water/anion-induced corrosion/decomposition. In this way, the CNF/MXene@Zn anode exhibits significantly enhanced coulombic efficiency (99.5 % at 10 mA cm(-2)) and low voltage hysteresis. Moreover, coated with CNF/MXene composite membrane, zinc symmetric batteries can be operated at the extremely high current of 100 mA cm(-2) and ultra-high Zn utilization of 88.2% to achieve record-high cumulative plating capacity of 12 Ah cm(-2). Furthermore, the full vanadium dioxide (VO2) |CNF/MXene@Zn batteries exhibit a high capacity of 357 mAh g(-1) at 2 A g(-1) and retain 93.3% of the capacity after 500 cycles. Moreover, at negative/ positive capacity (N/P) ratio of 2.8, the CNF/MXene membrane coated zinc is able to stably cycle for 100 cycles, demonstrating the potential for high energy zinc battery. This designed CNF/MXene membrane enables ZIBs as viable energy storage devices for practical applications.

Despite aggressive treatment and androgen-deprivation therapy, most prostate cancer patients ultimately develop castration-resistant prostate cancer (CRPC), which is associated with high mortality rates. However, the mechanisms governing the development of CRPC are poorly understood, and androgen receptor (AR) signaling has been shown to be important in CRPC through AR gene mutations, gene overexpression, co-regulatory factors, AR shear variants, and androgen resynthesis. A growing number of non-AR pathways have also been shown to influence the CRPC progression, including the Wnt and Hh pathways. Moreover, non-coding RNAs have been identified as important regulators of the CRPC pathogenesis. The present review provides an overview of the relevant literature pertaining to the mechanisms governing the molecular acquisition of castration resistance in prostate cancer, providing a foundation for future, targeted therapeutic efforts.

Zeolitic imidazolate framework-67 (ZIF-67) was synthesized on the surface of cellulose nanofibers (CNFs) in methonal to address the problems of unhomogeneous pore size and pore distribution of pure CNF membrane. A combination of Energy Dispersive X-Ray Spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS) and X-ray powder diffraction (XRD) patterns were used to determine the successful synthesis of ZIF-67@CNFs. The size of the ZIF-67 particles and pore size of the ZIF-67@CNF membrane were 50–200 nm and 150–350 nm, respectively. The prepared ZIF-67@CNF membrane exhibited excellent thermal stability, lower thermal shrinkage and high surface wettability. The discharge capacity retention of the Li-ion batteries (LIBs) made with ZIF-67@CNF, glass fiber (GF), CNF and commercial polymer membranes after 100th cycle at 0.5C rate were 88.41%, 86.22%, 83.27%, and 81.03%, respectively. LIBs with ZIF-67@CNF membrane exhibited a better rate capability than these with other membranes. No damage of porous structure or peel-off of ZIF-67 was observed in the SEM images of ZIF-67@CNF membrane after 100th cycle. The improved cycling performance, rate capability, and good electrochemical stability implied that ZIF-67@CNFs membrane can be considered as a good alternative LIB separator.

Solid-state zinc ion batteries (ssBs) based on hydrogel electrolytes have received tremendous attention due to their reliable safety, high flexibility and robust performance. However, freezing of the hydrogel electrolyte and resulting low ionic conductivity limit the capability of ssBs to work at low temperatures. Herein, a wood based cellulose nanofiber (CNF)–polyacrylamide (PAM) hydrogel electrolyte was developed with a hybrid methanol/water solvent. At the optimized methanol molar ratio of 56% (Me56), the hybrid electrolyte shows a low freezing point and high-Zn2+ reversibility. The reversibility of the Zn anode is boosted in this antisolvent since Zn2+ solvation is weakened and corrosion reactions are suppressed. With the Me56 hybrid electrolyte, MgVO/Zn batteries can deliver a high specific capacity of 214 mA h g−1 after 4000 cycles at 10 A g−1 (charging time: about 1 minute). The developed CNF–PAM hydrogel maintains high flexibility under repeated bending and twisting under very cold conditions. At an extremely low temperature of −60 °C, the ssBs still deliver a high specific capacity of about 140 mA h g−1 at 10 mA g−1 while remaining flexible, exhibiting great potential to be applied in wearable devices under cold conditions.

Volumetric performance of lithium ion batteries becomes increasingly significant in applications of miniaturized consumer electronics, such as cellphones. Herein, we report a successful design of compact Sn/SnO2 microspheres with a concentration gradient assembled by nanoparticles to realize high volumetric performance. In the structure, the secondary microsphere is able to offer more compact space in realizing higher volumetric capacity. The primary nanoparticles condense together, leading to a dense and porous structure, which can provide more efficient utilization of volume as well as effectively minimize volume variation. Due to the utilization of microstructure as well as the concentration gradient structure, the concentration gradient Sn/SnO2 microspheres deliver a high volumetric capacity (1593 mAh cm−3 at 200 mA g−1 after 200 cycles), outstanding rate capability (retaining a capacity of 1230 mAh cm−3), and stable cycling performance (a capacity retention of 97% after 900 cycles at 5 A g−1). This concentration gradient microsphere structure not only provide a high performance conversion-type composite anode, but also a strategy to engineer the energy density of anode materials in compact space towards high energy density.

The development of LiFePO

In comparison with well-protected rigid batteries with liquid electrolytes, solid-state batteries (ssBs) are more beneficial, offering high flexibility, high wearability and leakage prevention. Currently, ssBs with the capability of bending and twisting have been extensively studied. However, it remains a challenge to develop a highly stretchable ssB with the maintenance of high performance. Herein, we report a stable solid-state zinc ion battery (ssZIB) based on a cellulose nanofiber (CNF)–polyacrylamide (PAM) hydrogel electrolyte and a Mg0.23V2O5·1.0H2O cathode. The designed CNF–PAM hydrogel shows high stretchability and robust mechanical stability. Moreover, the porous CNF–PAM hydrogel electrolyte provides efficient pathways for the transportation of zinc ions. And the robust layered structure of V2O5·1.0H2O pillared with Mg2+ ions and water supports the fast insertion/extraction of zinc ions in the lattice. Therefore, the designed ssZIB shows unprecedented high capacity at high current with durable cycling life. At a current density of 5 A g−1 (charging time of around 3 minutes), the ssZIBs can deliver a high reversible capacity of 216 mA h g−1 after 2000 cycles and retain 98.6% of the initial capacity, showing a high capacity and long-life durability at high currents. Furthermore, the designed spring ssZIBs can work under stretching with the strain reaching 650%. And the designed ssZIBs are still operational even under repeated bending, freezing, and heating conditions. The ssZIBs show robust mechanical stability, high stretchability and impressive electrochemical performance, providing a potential pathway to expand the application of ZIBs to a broad range of practical energy storage devices.

Rechargeable aqueous zinc ion batteries are particularly attractive for large-scale application due to their features including low cost, environmental friendliness, and safety. Herein, we report the use of defect engineering to generate oxygen vacancies in tunneled α-MnO2 through surface gradient Ti doping for long-life Zn MnO2 battery. Interestingly, the introduction of surface gradient Ti doping leads to shrinkage of the interlayer, but simultaneously generates oxygen vacancies as compensated by electron due to the decreased valence state of Mn. Moreover, Ti substitution as well as the created oxygen vacancies open the [MnO6] octahedral walls and result in imbalanced charge distribution and local electric field in the crystal structure, accelerating ion/electron migration rates. Thus, diffusion coefficients of both Zn2+ and H+ ions in Ti MnO2 nanowires are improved. Consequently, the Ti MnO2 nanowires show improved both H+ and Zn2+ ions storage capacity in Zn/MnO2 battery and achieved excellent high-rate capability and ultralong cycling stability with a low capacity decay rate of 0.005% per cycle at high rate of 1 A g−1. It is believed that the intentionally created vacancies in this work opens up approaches to enhance existing materials that may have applications in more efficient and durable multi-valent ion battery and other technologies.

A two-dimensional (2D) layer-structured material is often a high-capacity ionic storage material with fast ionic transport within the layers. This appears to be the case for nonconversion layer str...

Objective: To determine the effect of convallatoxin on K562 cell proliferation and apoptosis. Methods: CCK-8 assay was used to detect cell proliferation; PI staining, JC-1 staining, and Annexin V-FITC/PI double staining were used to analyze the cell cycle, cell mitochondrial membrane potential, and cell apoptosis; and Western blotting was used to detect cleaved caspase-9, cleaved caspase-3, Bcl-2, Bax, and E2F1 expression and Akt phosphorylation. Subsequently, AutoDock software was used to determine the interaction between convallatoxin and Akt1. Results: Upon treatment with convallatoxin, the proliferation of K562 cells was inhibited, the cells were arrested at the S and G2/M phases, and cell apoptosis was significantly induced. In addition, Akt phosphorylation and E2F1 expression were significantly decreased, whereas E2F1 overexpression rescued convallatoxin-induced cell proliferation and apoptosis. In addition, a molecular docking assay indicated that convallatoxin could bind to Akt1. Conclusion: Convallatoxin inhibited cell proliferation and induced mitochondrial-related apoptosis in K562 cells by reducing the Akt-E2F1 signaling pathway, indicating that it is a potential agent for treating leukemia.

Magnetorheological fluids (MRFs) are smart fluids made of magnetic particles in a viscous carrier fluid, and their rheological properties are controllable by an external magnetic field. However, MR...

High cost platinum (Pt) catalysts limit the application of microbial electrolysis cells (MECs) for hydrogen (H

The globally extractable salinity gradient (SG) energy from the mixing of seawater and river water is estimated to be 3% of worldwide electricity consumption. Here we applied carbonized peat moss (CPM) electrodes to a capacitive concentration flow cell that is capable of harvesting SG energy based on the capacitive double layer expansion (CDLE) together with the Donnan potential. The electrodes were made from the visually inexhaustible peat moss by a facile and environmental benign pyrolysis process. With two identical CPM electrodes and a cation-exchange membrane, the cell produced a peak power density of 5.33 W m−2 and an average power density of 950 mW m−2, the highest ever reported for CDLE-based techniques, using synthetic seawater (30 g L−1 NaCl) and river water (1 g L−1 NaCl). The excellent performance was a result of the macroporous structure of the CPM electrodes, the assistance of Donnan potential, and the double-channel structure of the cell. This system was durable as it could extract energy from highly saline water (300 g L−1 NaCl) and it still worked well after 100 cycles. This study provides a new method to efficiently and continuously harvest SG energy based on the CDLE without an external charge.

Rechargeable aqueous zinc ion batteries are particularly attractive for large-scale application due to their low cost, environmental friendliness and safety. However, the development of zinc ion batteries is seriously impeded by the limited choice of suitable cathode materials owing to their low reversibility and slow diffusion of divalent zinc cations in cathodes. Herein, we report defect engineered MoS2-x nanosheets as cathode for Zn ion cells. These MoS2-x nanosheets show a preferential insertion of Zn ions into sulfur vacancies, allowing a much greater capacity to be obtained compared to pure MoS2. Combined STEM analysis, electrochemical study, and theoretical modeling reveal that numerous edge sites and sulfur vacancies act as preferential intercalation sites for the zinc ions, leading to a much greater capacity than that of defect-free MoS2. After 1,000 cycles at a specific current of 1,000 mA/g, the defect engineered MoS2-x electrode can still deliver a reversible capacity of 88.6 mAh/g, accounting for 87.8% of the initial capacity. The MoS2-x electrode displays excellent electrochemical performance, making it a highly promising cathode material for future zinc ion batteries. It is believed that our strategy to use the chemistry of defects to unlock the electrochemical activity of known materials can be applied to other materials for practical divalent/multivalent batteries.

Developing efficient, stable, and low-cost catalysts for oxygen evolution reaction (OER) is highly desired in water splitting and metal–air batteries. Transition metal–organic frameworks (MOFs) have emerged as promising catalysts and have been intensively investigated especially due to their tunable crystalline structure. Unlike traditional strategies of tuning the morphology of well-crystalline MOFs, low-crystalline bimetallic MOFs are constructed via inducing exotic metal ions, and the formation process is revealed by experimental and theoretical methods. The low-crystalline bimetallic MOFs exhibit rich active sites due to local crystallinity and long-range disorder and deliver a small overpotential of 260 mV at 10 mA cm–2, a low Tafel slope of 35 mV dec–1, and a high Faradaic efficiency of 99.5% as oxygen evolution elecctrocatalysts. The work opens up a new avenue for the development of highly efficient earth-abundant catalysts in frontier potential applications.

Aqueous Zn-ion batteries are desirable for large-scale application over Li-ion batteries due to the low cost, high safety and environment friendliness. However, the development of Zn-ion batteries is seriously impeded by a limited choice of positive electrodes. Herein, we report an electrochemical activated porous MoO2/Mo2N heterostructured nanobelts cathode. During the electrochemical activation, it is interesting to find that MoO2 grains in-situ generate in Mo2N matrix. The generated MoO2 grains can not only accommodate the intercalated zinc ions, leading to high reversible capacity, but also provide high electronic conductivity, thereby improving the rate capability. On the other hand, the Mo2N matrix could protect the MoO2 grains from structure degradation during cycling and keep stable in the slight acidic electrolyte. Based on the synergic effect of MoO2 and Mo2N, electrochemical activated MoO2/Mo2N heterostructured nanobelts exhibit a high reversible capacity of 113 mAh/g at high current density of 1 A/g for 1000 cycles, showing long-term cyclic stability (capacity retention is 78.8%) and remarkable rate capability. It is believed that the superior performance is attributed to the synergistic effect of integrated MoO2 grains and Mo2N nanobelt matrix. This strategy of electrochemical activation process can be expanded to other metal nitride as zinc battery cathode.

Layered metal dichalcogenides (LMDs) semiconducting materials have recently attracted tremendous attention as high performance gas sensors due to unique chemical and physical properties of thin layers. Here, three-dimensional SnS2 nanoflower structures assembled with thin nanosheets were synthesized via a facile solvothermal process. When applied to detect 100ppm NH3 at 200°C, the SnS2 based sensor exhibited high response value of 7.4, short response/recovery time of 40.6s/624s. Moreover, the sensor demonstrated a low detection limit of 0.5ppm NH3 and superb selectivity to NH3 against CO2, CH4, H2, ethanol and acetone. The excellent performance is attributed to the unique thin layers assembled flower-like nanoarchitecture, which facilitates both the carrier charge transfer process and the adsorption/desorption reaction. More importantly, it was found that the sensor response enhanced with increasing oxygen content in background and was improved by 3.57 times with oxygen content increasing from 0 to 40%. The increased response is owing to the enhanced binding energies between SnS2 and NH3 moleculers. Theoretically, density functional theory was employed to reveal the NH3 adsorption mechanism in different background oxygen contents, which opens a new horizon for LMD based structures applied in various gas sensing fields.

In this paper, we present a novel method to estimate the dense scene flow from the aligned depth map and color image using variational framework. For scene flow estimation, most scenes can be seen as scenes composed by independent 3-D rigid parts, so we apply 3-D local rigidity assumption to data term as a fidelity measure for each pixel. Meanwhile, in order to improve the accuracy of scene flow estimation at the boundaries of motion, we assume that depth map and color image are aligned and utilize the boundaries information of depth map to yield smoothness term which is weighted by a depth map driven anisotropic diffusion tensor. In addition, an efficient numerical algorithm named primal-dual algorithm is implemented for the variational formulation of scene flow estimation. Our method is tested on the Middlebury data sets, and the real-world scene data set captured by KINECT. Experimental results show that our method can receive dense and accurate scene flow and preserve motion boundaries well.

Current energy storage device has fallen short behind from the fast growing requirement for (hybrid) electric vehicles and portable devices including mobile phones, which drives the lithium metal anode to be a research hot topic. However, the large volume change of lithium metal anode induces instable solid electrolyte interface (SEI) layer, which prevents its further development. A stable SEI layer required flexible surface to accommodate the large volume variation and inorganic core with low Li+ partial molar volume for dendrite suppression. Herein, we achieved a gradient SEI which is composed of flexible surface-rich polycarbonate moieties and low Li+ partial molar volume inorganic LiF-rich core by applying liquid alloy GaSnIn as electrolyte additive. Initially, the calculation verified that liquid alloy GaSnIn as electrolyte additive would facilitate the initial decomposition of LiPF6, and lead to the formation of the gradient SEI layer. In the Li||Li half‐cell test, we successfully achieved dense deposition of Li metal and in this way, the cycling performance with liquid alloy GaSnIn as electrolyte additive is greatly improved especially at high rate (10 mA cm−2). Voltage polarization was greatly reduced and Coulombic efficiency was effectively improved due to the gradient SEI layer achieved in the interface of Li anode and electrolyte. In the Li||LFP cell, high average coulombic efficiency (99.06%) at long cycle life (＞2500 cycles) is achieved for the liquid alloy GaSnIn‐protected Li metal anode at high areal capacity (3 mAh/cm2). These results deepen our understanding on liquid alloy as a promising electrolyte additive for efficient dendrite suppressing, enabling the practical lithium metal batteries (LMBs).

Li-excess layered materials, such as Li[Li0.2Mn0.54Ni0.13Co0.13]O2 (LMNCO) et al. are promising cathode materials that can be used in batteries for hybrid electric vehicles (HEV)/electric vehicles (EV), due to their excellent lithium-storage capability and very high energy density. Dramatic capacity loss during electrochemical cycling seriously hinders their practical implementation. It is found that the LMNCO layered cathode material suffers from structural instability and irreversible layered-to-spinel phase transition during lithiation/delithiation, leading to dramatic loss of capacity and deteriorated electrochemical kinetics. To overcome this challenge, we synthesize spinel-structured LHMNCO TBA nanowires using an electrospinning method followed by facile ion-exchange promoted phase transition. After 100 electrochemical cycles at the specific current 0.5 C, spinel-structured LHMNCO TBA still retains a capacity of about 200 mAh/g, corresponding to a capacity retention ratio of 90.5%, much higher than that of layered LMNCO nanowires, which only maintains a specific capacity of 137 mAh/g with only 48.9% capacity retention.

Porous transitional metal oxides hollow polyhedrons with controlled components have attracted tremendous attention due to their widespread applications. In this paper, novel porous ZnO-decorated Co3O4 hollow polyhedrons were synthesized by thermal decomposition of zeolitic imidazolate frameworks (ZIF-67) as self-sacrificial templates at 300 °C. Experimental results reveal that the porous 2 mol% ZnO-Co3O4 hollow polyhedrons present excellent response value of 106, short response/recovery time of 7/236 s to 1000 ppm ethanol at the optimal temperature of 200 °C, much higher than that of pure Co3O4 porous hollow polyhedrons (response value of only 5.39, response/recovery time of 9/323 s). Additionally, the 2 mol% ZnO-Co3O4 manifests a low detection limit of 1 ppm ethanol with a high response value of 1.57 and an applausive selectivity toward ethanol as compared to NH3, H2, CH4, CO2 and CH3COCH3. The enhanced gas sensing performance can be attributed to the formation of p-n heterojunction between Co3O4 and ZnO, as well as the porous hollow nanostructure with high porosity, large specific surface area, and remarkable capabilities of adsorbing oxygen. Our work offers a new avenue to employ ZIF-67 as templates for the fabrication of other hollow metal oxides with well-defined structures. More importantly, it demonstrates a great potential for the application of porous ZnO-Co3O4 hollow polyhedrons heterostructure to detect other gases.

Hollow heterostructured nanomaterials have received tremendous interest in new-generation electrocatalyst applications. However, the design and fabrication of such materials remain a significant challenge. In this work, we present Co3O4–x-carbon@Fe2–yCoyO3 heterostructural hollow polyhedrons that have been fabricated by facile thermal treatment followed by solution-phase growth for application as efficient oxygen evolution reaction (OER) electrocatalysts. Starting from a single ZIF-67 hollow polyhedron, a novel complex structured composite material constructed from Co3O4–x nanocrystallite-embedded carbon matrix embedded with Fe2–yCoyO3 nanowires was successfully prepared. The Co3O4–x nanocrystallite with oxygen vacancies provides both heterogeneous nucleation sites and growth platform for Fe2–yCoyO3 nanowires. The resultant heterostructure combines the advantages of Fe2–yCoyO3 nanowires with the large surface area and surface defects of Co3O4–x nanocrystallite, resulting in improved electrocatalytic activ...

Cobalt oxides are attractive high-capacity anode materials in lithium ion batteries yet suffer from fast capacity fading and low rate capability. Herein, we have prepared well-dispersed cobalt oxide nanoparticles encapsulated within a flexible single-walled carbon nanotubes matrix (marked as Co 3 O 4 NPs@SWCNT), for the first time, through a facile evaporation-induced self-assembly (EISA) of single-walled carbon nanotubides (SWCNTDs). By varying the loading amount of Co 3 O 4 content in the composite, the optimal Co 3 O 4 NPs@SWCNT exhibits a high capacity of 1286 mAh g −1 after 140 cycles at 100 mA g −1 . When the specific current returns from 5000 mA g −1 to 100 mA g −1 , it still maintains a specific capacity of 1109 mAh g −1 , demonstrating remarkable cycling stability and high rate capability. Moreover, the optimal Co 3 O 4 NPs@SWCNT demonstrates superior prolonged cycling stability for over 200 and 600 cycles at extremely high specific currents of 1000 and 2000 mA g −1 , respectively. Such impressive electrochemical properties are mainly ascribed to the synergic effect of Co 3 O 4 nanoparticles and SWCNTs in the heterostructure, in which the robust SWCNTs not only offer excellent strain accommodation of the encapsulated Co 3 O 4 upon long-term cycling, but also significantly enhance overall electric conductivity and mechanical stability of the electrodes. The facile and effective strategy demonstrated here can be extended to design various SWCNT-based hybrid nanostructures for applications in supercapacitors, water splitting and other fields.

The commercialization of dye-sensitized solar cells (DSSCs) has been severely hindered by high cost and scarcity of Pt as counter electrode (CE). Up to date, the design of low-cost Pt-free CE materials with an ideal combination of high electrical conductivity, excellent catalytic activity and satisfactory long-term electrochemical stability still poses challenges to researchers. In this work, we have developed novel CoNi alloy@carbon nanotubes embedded carbon nanocages (CoNi@CNTs-C) as the CE of DSSCs for the first time, by applying Co/Ni bimetallic metal organic framework (MOF) as the template. The power conversion efficiency (PCE) of DSSCs can be maximized by simply optimizing the ratio of Ni 2+/ Co 2+ precursor ratio during the synthesis. As a result, the DSSC based on CoNi@CNTs-C-200 CE with a Co/Ni atomic ratio of 9:1 exhibits a remarkable PCE of 9.04%, showing a ∼15% enhancement compared to that of Pt CE (7.88%). Notably, the CoNi@CNTs-C-200 CE also demonstrates excellent long-term electrochemical stability over 300 cyclic voltammetry cycles, which is much superior to that of conventional Pt CE. Thus, the CoNi@CNTs-C demonstrates a great potential as a low-cost, stable and efficient CE material for next-generation DSSCs.

SnS2 as a high energy anode material has attracted extensive research interest recently. However, the fast capacity decay and low rate performance in alkaline-ion batteries associated with repeated volume variation and low electrical conductivity plague them from practical application. Herein, we propose a facile method to solve this problem by synthesizing porous SnS2 microflowers with in-situ formed sulfur vacancies. The flexible porous nanosheets in the three-dimensional flower-like nanostructure provide facile strain relaxation to avoid stress concentration during the volume changes. Rich sulfur vacancies and porous structure enable the fast and efficient electron transport. The porous SnS2&minus, x microflowers exhibit outstanding performance for lithium ion battery in terms of high capacity (1375 mAh g&minus, 1 at 100 mA g&minus, 1) and outstanding rate capability (827 mA h g&minus, 1 at high rate of 2 A g&minus, 1). For sodium ion battery, a high capacity (~522 mAh g&minus, 1) can be achieved at 5 A g&minus, 1 after 200 cycles for SnS2&minus, x microflowers. The rational design in nanostructures, as well as the chemical compositions, might create new opportunities in designing the new architecture for highly efficient energy storage devices.

SnS2 as a high energy anode material has attracted extensive research interest recently. However, the fast capacity decay and low rate performance in alkaline-ion batteries associated with repeated volume variation and low electrical conductivity plague them from practical application. Herein, we propose a facile method to solve this problem by synthesizing porous SnS2 microflowers with in-situ formed sulfur vacancies. The flexible porous nanosheets in the three-dimensional flower-like nanostructure provide facile strain relaxation to avoid stress concentration during the volume changes. Rich sulfur vacancies and porous structure enable the fast and efficient electron transport. The porous SnS2−x microflowers exhibit outstanding performance for lithium ion battery in terms of high capacity (1375 mAh g−1 at 100 mA g−1) and outstanding rate capability (827 mA h g−1 at high rate of 2 A g−1). For sodium ion battery, a high capacity (~522 mAh g−1) can be achieved at 5 A g−1 after 200 cycles for SnS2−x microflowers. The rational design in nanostructures, as well as the chemical compositions, might create new opportunities in designing the new architecture for highly efficient energy storage devices.

A two-dimensional (2D) layer-structured material is often a high-capacity ionic storage material with fast ionic transport within the layers. This appears to be the case for nonconversion layer structure, such as graphite. However, this is not the case for conversion-type layered structure such as transition-metal sulfide, in which localized congestion of ionic species adjacent to the surface will induce localized conversion, leading to the blocking of the fast diffusion channels and fast capacity fading, which therefore constitutes one of the critical barriers for the application of transition-metal sulfide layered structure. In this work, we report the tackling of this critical barrier through nanoscale engineering. We discover that interconnected vertically stacked two-dimensional-molybdenum disulfide can dramatically enhance the cycling stability. Atomic-level in situ transmission electron microscopy observation reveals that the molybdenum disulfide (MoS

Rechargeable zinc-ion batteries (ZIBs) have shown great potential for grids-level energy storage system. However, the lack of desirable and stable cathode materials remains challenging. Herein, Sn1.5V2O7(OH)2•3.3H2O, in which pyrovanadate V2O74− group pillared with Sn oxide layer, is developed as an advanced cathode for ZIBs and a hidden reaction mechanism in SnVO cathode through in-situ Raman and ex-situ XANEs, involves the opening of V˭O edge bonding and formation of Sn–O–V bonding, which leads to charge screening effect and facilitates the fast diffusion kinetics for zinc ions, as quantitatively verified by kinetic analysis. Additionally, the tetravalent Sn ions bring about stronger ionic bonds, binding to pyrovanadate V2O74− group and leading to good stability in the pyrovanadate framework, which guarantee the cycling stability. As a result, the as-prepared SnVO shows long cycling life as well as excellent rate capability. We demonstrate that, even cycled at high current of 10 A/g, the SnVO cathode can still retain a capacity of 130 mAh/g for over 500 cycles, indicating remarkable high capacity at high rate. Our findings reveal that the tetravalent tin ions have a strong beneficial effect on the battery performance of the layered-structure cathode materials. It is believed that our study would boost further studies in other multi-valent rechargeable batteries.

Co3O4, as an attractive lithium ion battery anode material, though benefited from its high theoretical capacity, has long suffered from low electrical transportation and dramatic volume variations. Therefore, to develop a LIB anode material with both good capability and excellent stability, rational design of composite material is becoming an appealing method. Herein, we report a scalable method of fabricating integrated Co3O4/TiO2 composite hollow polyhedrons through a cation-exchange approach in metal-organic framework. In this synthesis, well-defined ZIF-67 particles not only serve as the host to accommodate exchanged titanium cations but also the template to form hollow polyhedron structure. The obtained integrated Co3O4/TiO2 composite hollow polyhedrons exhibit a high reversible capacity of 642 mAh/g at a rate of 500 mA/g after 200 cycles, accounting for 96.9% of the initial capacity, much higher than that of pure Co3O4, which only maintain a specific capacity of 200 mAh/g and a capacity retention of 40%. The optimized integrated Co3O4/TiO2 composite hollow polyhedrons display significant improvements in electrochemical performance, demonstrating great potential as advanced anode material for future lithium ion batteries.

The applications of alloying/dealloying materials as anode for LIB electrode are hindered by its dramatic volume variations and sluggish kinetics. Herein, to overcome these challenges, we report a facile and scalable approach fabricating coral-like SnO2/C composite electrodes through a top-down strategy followed by a sol–gel carbon-coating method. During the synthesis, well-defined SnS2 nanoflowers and dopamine serve as structural template and carbon source for integrating the desired structure. The three-dimensional coral-like SnO2/C composite exhibits a high reversible capacity of 648 mAh g−1 after 50 electrochemical cycles and a low capacity fading of 0.778 % per cycle from the 2nd to the 50th cycle, demonstrating an outstanding cycling stability. It also shows a discharge capacity of 1294, 784, 658, 532, and 434 mAh g−1 at a specific current of 100, 200, 500, 1000 and 2000 mAh g−1, respectively, and retains a specific capacity of 719 mAh g−1 when the specific current goes back to 100 mA g−1, displaying an excellent rate capability. Compared to SnS2 nanoflowers and bare interconnected SnO2 nanoparticles anode, the optimized coral-like SnO2/C composite shows significantly improved electrochemical performances in terms of rate capability and cycling reversibility, demonstrating great potential as superior anodes in next-generation lithium ion batteries.

A sandwich-like, graphene-based porous nitrogen-doped carbon (PNCs@Gr) has been prepared through facile pyrolysis of zeolitic imidazolate framework nanoparticles in situ grown on graphene oxide (GO) (ZIF-8@GO). Such sandwich-like nanostructure can be used as anode material in lithium ion batteries, exhibiting remarkable capacities, outstanding rate capability, and cycling performances that are some of the best results among carbonaceous electrode materials and exceed most metal oxide-based anode materials derived from metal orgainc frameworks (MOFs). Apart from a high initial capacity of 1378 mAh g–1 at 100 mA g–1, this PNCs@Gr electrode can be cycled at high specific currents of 500 and 1000 mA g–1 with very stable reversible capacities of 1070 and 948 mAh g–1 to 100 and 200 cycles, respectively. At a higher specific current of 5000 mA g–1, the electrode still delivers a reversible capacity of over 530 mAh g–1 after 400 cycles, showing a capacity retention of as high as 84.4%. Such an impressive electrochemical performance is ascribed to the ideal combination of hierarchically porous structure, a highly conductive graphene platform, and high-level nitrogen doping in the sandwich-like PNCs@Gr electrode obtained via in situ synthesis. Accepted version

Metal vanadates suffer from fast capacity fading in lithium-ion batteries especially at a high rate. Pseudocapacitance, which is associated with surface or near-surface redox reactions, can provide fast charge/discharge capacity free from diffusion-controlled intercalation processes and is able to address the above issue. In this work, we report the synthesis of macroporous CoV2O6 nanosheets through a facile one-pot method via acetylene black induced heterogeneous growth. When applied as lithium-ion battery anode, the macroporous CoV2O6 nanosheets show typical features of pseudocapacitive behavior: (1) currents that are mostly linearly dependent on sweep rate and (2) redox peaks whose potentials do not shift significantly with sweep rate. The macroporous CoV2O6 nanosheets display a high reversible capacity of 702 mAh g(-1) at 200 mA g(-1), excellent cyclability with a capacity retention of 89% (against the second cycle) after 500 cycles at 500 mA g(-1), and high rate capability of 453 mAh g(-1) at 5000 mA g(-1). We believe that the introduction of pseudocapacitive properties in lithium battery is a promising direction for developing electrode materials with high-rate capability.

Low electrical conductivity of the cathode for rechargeable aqueous Zn-ion batteries (RAZIBs) significantly limits the rate capability and shortens the cycling life. Herein, a highly stable composite is developed as a promising cathode by directly growing non-oriented H2V3O8 nanowires on 2D Mxene sheets. This composite architecture shows enhanced electrical conductivity and faster diffusion for charge transportation, resulting in improved rate performance and prolonged cycling life. Compared with the pristine H2V3O8 (306 mAh·g−1 at 0.2 A·g−1 and 900 cycles at 5 A·g−1), the resultant H2V3O8/Mxene composite exhibits larger specific capacities (365 mAh·g−1 at 0.2 A·g−1) and longer cycling life (≈84% capacity retention over 5600 cycles at 5 A·g−1). Even at 10 and 20 A·g−1, this composite cathode also delivers capacities of 164 and 73 mAh·g−1 for over 1900 and 500 cycles, respectively. Such superior electrochemical performance of RAZIB is ascribed to the enhanced electrical conductivity and improved charge transport kinetics. Furthermore, the reversible co-intercalation electrochemical reaction mechanism of Zn2+ and water was systemically demonstrated through various ex-situ characterizations. Additionally, highly safe and flexible solid-state ZIBs with polyacrylamide/cellulose nanofiber (CNF) hydrogel electrolyte deliver high capacities (317.4 mAh·g−1 at 0.2 A·g−1) and long cycle life (over 6600 cycles at 10 A·g−1). The solid-state batteries are still workable even at different harsh environments, such as freezing at −18 ℃ (152.5 mAh·g−1 at 0.5 A·g−1) and heating at 40 ℃ (307.3 mAh·g−1 at 0.5 A·g−1).

Aqueous rechargeable batteries hold the potential for the application in large-scale energy storage system due to low cost, environmentally friendliness, and high safety. In the past several decades, tremendous research efforts have been devoted to the batteries with metal ions as charge carriers. However, little attention is paid to the non-metal charge carriers, such as ammonium ions. In this work, layered iron vanadate nanosheets are first introduced as ammonium ion storage electrode. In comparison with the Na+ and K+ storage performance, iron vanadate nanosheets show a much improved pseudocapacitance behavior with NH4+ as charge carriers. In this way, at the high current density of 5 A/g, the FVO nanosheets in aqueous (NH4)2SO4 electrolyte display the highest specific capacity of 72.5 mAh/g for 500 cycles, compared with the FVO nanosheets in Na2SO4 (64.7 mAh/g) and K2SO4 (17.3 mAh/g). The difference is attributed to the dirctional H-bondings between the intercalated NH4+ ions and the host iron vanadate nanosheets. This work provides a new direction to expand aqueous batteries with ammonium ion as charger carriers.

The emerging earth-abundant metal phosphides are regarded as promising bifunctional water splitting electrocatalysts. However, the real active sites in metal phosphides remain a debate. Herein, the hierarchical flower-like NiCoP microsphere is designed with the outstanding performance toward both hydrogen and oxygen evolution reaction (overpotentials of 238 and 47 mV for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) at 10 mA cm−2, respectively). The symmetrical overall water splitting devices based on NiCoP only require an ultralow voltage of 1.52 V to reach 10 mA cm−2, which is rarely reported. In-situ Raman and ex-situ TEM/XPS reveal that the surface reconstruction of designed NiCoP pre-catalysts transforms into metallic Ni(Co) for HER and Ni(Co)OOH for OER, respectively. The degradation process of HER during resting is revealed, suggesting the formation of high valence state Ni(Co)(OH)2 and blocking the active sites. We believe that the comprehensive understanding of the surface reconstruction of electrode is crucial in understanding the fundamental mechanism.

Hypoxia serves a critical role in the pathogenesis of liver fibrosis. Hypoxia‑inducible factor 1α (HIF1‑α) is induced when cells are exposed to low O2 concentrations. Recently, it has been suggested that Rho‑associated coiled‑coil‑forming kinase 1 (ROCK1) may be an important HIF1‑α regulator. In the present study, it was analyzed whether crosstalk between HIF1‑α and ROCK1 regulates cell proliferation and collagen synthesis in hepatic stellate cells (HSCs) under hypoxic conditions. For this purpose, a rat hepatic HSC line (HSC‑T6) was cultured under hypoxic or normoxic conditions, and HIF1‑α and ROCK1 expression was measured at different time points. Additionally, HSC‑T6 cells were transfected with HIF1‑α small interfering RNA (siHIF1‑α), and measured protein expression and mRNA transcript levels of α‑smooth muscle actin, collagen 1A1 and ROCK1. Collagen 3A1 secretion was also measured by ELISA. Cell proliferation was assessed by the MTT assay under these hypoxic conditions. The results indicated that a specific ROCK inhibitor, Y‑27632, increased HIF1‑α and ROCK1 expression over time in HSC‑T6 cells in response to hypoxia. In addition, knockdown of HIF1‑α inhibited HSC‑T6 proliferation, suppressed collagen 1A1 expression, decreased collagen 3A1 secretion and attenuated ROCK1 expression. Notably, ROCK1 inhibition caused HSC‑T6 quiescence, suppressed collagen secretion and downregulated HIF1‑α expression. Collectively, these findings indicated that the interplay between HIF1‑α and ROCK1 may be a critical factor that regulates cell proliferation and collagen synthesis in rat HSCs under hypoxia.

The exploration of new inexpensive rechargeable batteries with high energy-density electrodes is a key to integrate renewable sources such as solar and wind, and address sustainability issues. Herein, a facile and scalable method is developed to prepare a two-dimensional earth-abundant jarosite-KFe3(SO4)2(OH)6/rGO hybrid via a solution-phase oxidation process at elevated temperature. In this synthesis, single-layer graphene sheets serve as both structure-directing agents and growth platforms to directly grow monocrystalline KFe3(SO4)2(OH)6 nanoplates with unique hexagonal shapes, forming a KFe3(SO4)2(OH)6/rGO hybrid. As a cathode for lithium batteries, the hybrid structure exhibits a high reversible capacity of 120.5 mA h g−1 after 100 cycles at a specific current of 2C and thus retains 88% of the maximum capacity. The monocrystalline jarosite-KFe3(SO4)2(OH)6-nanoplates/rGO hybrid exhibits a discharge capacity of 143.6, 113.9, 98.2, 83.9 and 65.9 mA h g−1 at 1, 2, 5, 10, and 20C, respectively, and retains a specific capacity of 134.4 mA h g−1 when the specific current returns from 20C to 1C, displaying an excellent rate capability. At a high rate of 10C, the jarosite-KFe3(SO4)2(OH)6/rGO composites maintained 70.7 mA h g−1 after 300 cycles with a capacity retention of 78.2%, indicating remarkable cycling stability even at a high rate. Compared with KFe3(SO4)2(OH)6 particles, the KFe3(SO4)2(OH)6/rGO nanocomposites exhibit remarkably prolonged cycling life and improved rate capability. Therefore, the earth-abundant jarosite-KFe3(SO4)2(OH)6/rGO hybrid demonstrates great potential for application as a high-performance cathode material in new-generation lithium-ion rechargeable batteries.