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The integration of nickel (Ni) nanoparticle (NP)-embedded carbon layers (Ni@C) into the three-dimensional (3D) hierarchically porous carbon architectures, where ultrahigh boron (B) and nitrogen (N) doping is a potential methodology for boosting Ni catalysts' water splitting performances, was achieved. In this study, the novel 3D ultrafine Ni NP-embedded and B- and N-codoped hierarchically porous carbon nanowires (denoted as Ni@BNPCFs) were successfully synthesized via pyrolysis of the corresponding 3D nickel acetate [Ni(AC)

This paper proposes the preparation of a S-Se-Ti3C2Tx/TiO2 cathode by etching Ti3AlC2 with hydrofluoric acid and doping with selenium (Se). Through an electrochemical performance test, selenium is doped into the active material sulfur and forms a sulfur-selenium compound to compensate for the ‘chemical inertness’ of the elemental sulfur, thereby increasing the utilization rate of the active material. Taking advantage of the ability of TiO2 to absorb polysulfide compounds and the high conductivity of carbides, the Ti3C2Tx composite material, modified with TiO2 nanodots, is constructed in situ as a sulfur-selenium composite material carrier, achieving a high sulfur content of 80%. S-Se-Ti3C2Tx/TiO2 is used as the cathode, and the initial discharge specific capacity is as high as 1073 mAh g−1, which improves the utilization of active materials and effectively inhibits the shuttle effect of lithium polysulfide intermediates.

Inflammation is thought to play an important role in the pathophysiology of ischaemic stroke, which is a main cause of disability and morbidity worldwide. Inhibition of the NOD-like receptor protein 1 (NLRP1) inflammasome has been reported to alleviate the inflammatory response in cell and animal models. Ligustroflavone (LIG) is a compound derived from Ligustrum lucidum, which shows anti-inflammatory activity and may play a beneficial role in a number of neurological diseases. To date, the potential for LIG to act through NLRP1 as a treatment for ischemic stroke has not been studied. The present study established an ischaemic stroke model by middle cerebral artery occlusion (MCAO). Modified neurological severity scoring, open-field and the Rotarod test were used to assess neurological deficits. Staining with Hoechst 33258 and western blotting were used to evaluate neuronal damage. Expression levels of NLRP1 inflammasome complexes and inflammatory cytokines were determined using western blotting, enzyme-linked immunosorbent assay and reverse transcription-quantitative PCR. Treatment with LIG minimized the impairment of neurological function and blocked neuronal damage in MCAO mice. In addition, treatment with LIG attenuated the upregulation of expression levels of the NLRP1 inflammasome complexes and the inflammatory cytokines TNF-α, IL-18, IL-6 and IL-1β. Overall, LIG played an important role in anti-inflammatory and neuroprotective activity in MCAO models of ischaemic stroke.

Nickel sulfides are perfect anode materials for high-capacity and low-cost lithium-ion batteries (LIBs); however, with the shortcoming of polysulfide intermediate dissolution, volume expansion exceeding the limit during cycling also restricts their development. Herein, NiS/C composite materials are successfully anchored on chestnut shell fluff (CSF)-derived biochar by a glucose-auxiliary hydrothermal method along with an annealing treatment. The CSF biochar acts as an effective electron transmission channel for the rapid lithiation/delithiation of NiS and as a fixed sulfur carrier for inhibiting the dissolution of polysulfide. Glucose restrains the accumulation of NiS particles and then transforms into uniform amorphous carbon during annealing, which is more effective in buffering for rapid volume variation. Moreover, the CSF-NiS/C electrode exhibits a remarkable specific capacity of 1522.8 mAh g-1 (0.1 A g-1) and distinguished rate performance with 295 mAh g-1 capacity (3 A g-1), which are better than those of the pure NiS/C anode material displays. Researchers may be inspired by both of these reasonable design and synthesis strategies that are beneficial for the development of high-performance nickel-based sulfide anode materials for LIBs.

The Fe-13Cr-4Al alloy has become a promising candidate material for accident tolerance fuel (ATF) cladding of light-water reactors (LWRs) due to its excellent oxidation resistance to high-temperature water vapor. However, the tensile deformation behavior of the Fe-13Cr-4Al alloy under different strain rates at different temperatures is still unclear. In the present study, the tensile behavior and deformed microstructure of the Fe-13Cr-4Al alloy were investigated at strain rates from 5 × 10–4 to 1 × 10–2 s−1 in the temperature range from RT to 600 °C. Serrations were observed in the tensile engineering stress–strain curves of the intermediate temperature ranging from 300 to 450 °C at all the three strain rates, indicating the occurrence of dynamic strain aging (DSA). As the strain rate increased, the temperature range where serrated plastic flow occurred shifted to the high temperature regime. Serrated plastic flow occurred after a certain critical plastic strain, and the critical plastic strain decreased with the increase in temperature and increased with the increase in strain rate. In the DSA regime of the Fe-13Cr-4Al alloy, the plateau in the yield strength, ductility minima, negative strain rate sensitivity, the peaks of strain hardening exponent and work hardening rate were observed, which were the typical manifestations of the DSA. The activation energies of serrated plastic flow evaluated by three different methods were 157 ± 35, 92 ± 10 and 93 ± 10 kJ/mol, respectively. According to the values of activation energy, the controlling mechanism responsible for the DSA of the Fe-13Cr-4Al alloy was found to be the interaction between substitutional aluminum atoms and dislocations. The fracture surfaces of the specimens tested at 400 °C under three strain rates showed the mixed fracture mode, which contained dimples and cleavage facets. The tensile samples at 600 °C showed a completely ductile fracture mode with large and deep dimples. A large number of dislocation tangles in the microstructure of the specimens tested at 400 °C under all the strain rates were observed, with a large amount of Fe2Nb Laves particles along the grain boundaries and in the matrix. Dislocation pile-up was also observed around the grain boundaries and second-phase particles. With the increase in the strain rate, the number of subgrains increased, and a clear dislocation cell structure was also observed.

Lithium-sulfur (Li-S) batteries are considered to be one of the next-generation battery candidates and have been widely studied. Despite the obvious advantages of Li-S batteries, there are still many serious problems with sulfur electrode: The active material sulfur (S) and the final product lithium sulfide (Li2S) are both insulators, and the electronic conductivity is poor, so that a large amount of conductive agent must be added to the sulfur electrode; the large difference in density between S and Li2S makes the electrode undergo a huge volume change (about 80%) during the charge and discharge process, which easily leads to the collapse of the sulfur electrode structure, which leads to the degradation of the Li-S batteries performance; the lithium polysulfide produced during charge and discharge has extremely high solubility in ether electrolytes, resulting in the “shuttle effect”. Especially, the “shuttle effect” of lithium polysulfide has caused problems such as poor battery cycle performance, rapid capacity decay and overcharge, which severely restricted the further development and commercial application of Li-S batteries. As a key component of Li-S batteries, electrolyte not only plays a role in transmitting lithium cation (Li+) and conducting internal circuits, but also one of the main factors that determine the overall performance of the battery capacity and cycle stability. Lithium nitrate (LiNO3) has received widespread attention as an electrolyte additive for Li-S batteries, and its mechanism of action has also been studied in depth. However, this article provides a new understanding of the mechanism of LiNO3 additives through deep study and new experimental schemes. In this experimental scheme, the Li metal anode recycled by electrolyte containing LiNO3 additive and fresh sulfur electrode was used to reassemble the battery with the electrolyte without the LiNO3 additive; the sulfur electrode recycled by electrolyte containing LiNO3 additive and fresh Li metal anod were used to reassemble the battery with the electrolyte without the LiNO3 additive; both batteries have serious overcharging during the charging process, and the shuttle of polysulfide anions occurs. This shows that the mechanism of LiNO3 inhibiting the “shuttle effect” is not just to form SEI film. Through the ion migration number test, it is found that after adding LiNO3 additive, the migration number of Li+ increases, resulting in a significant decrease in the migration of polysulfide anions. It can be concluded that another effect of adding LiNO3 additives is to increase the migration number of Li+, thereby reducing the migration number of anions and effectively inhibiting the “shuttle effect”. At present, the components of gunpowder (sulfur, nitrate, carbon) are concentrated in Li-S batteries, which may be potentially dangerous during commercial use. According to the new discovery of the role of LiNO3 additives in Li-S batteries in this work, future research work can be based on the migration number theory to find other electrolyte additives that can promote the migration number of lithium ions and interact with polysulfide anions. LiNO3 additives, thereby reducing the potential dangers of Li-S batteries in use.

Transition metal sulfides are the promising anode materials for high-capacity sodium-ion batteries (SIBs). However, the pitfalls of poor conductivity and large volume expansion still restrict their applications. Herein, NiS/C with a uniform flower-like structure was successfully synthesized via a glucose-assisted hydrothermal method coupled with post-annealing strategy. The petal-shaped configuration shortens the diffusion path of sodium ions in electrochemical reaction. Significantly, the formed uniform amorphous carbon is more effective in improving the electrical conductivity of electrode materials and buffering for the rapid volume change. When regarded as the anode of SIBs, the NiS/C electrode delivers a high reversible specific capacity of 1042.3 mAh g−1 at 0.1 A g−1. The excellent electrochemical performance shows that the NiS/C offers great potential for the development and research of large-scale energy storage of metal sulfide electrodes in the future.

A series of morphology-selected copper ferrite (CuFe2O4) anode materials for sodium ion batteries were firstly prepared via a highly efficient spray drying method using glycine as the complex and accelerator. It was found that the glycine/nitrate (G/N) molar ratio has an important influence on the crystallinity, morphology and electrochemical properties of sodium storage. Compared with the other prepared materials, the G/N-0.3 (glycine-nitrate molar ratio of 0.3) exhibits the most excellent electrochemical performance. The excellent electrochemical properties can be attributed to the optimized molar ratio of glycine-nitrate, which induce a good crystallinity with a proper porous structure, thereby improving the cycle life of the battery.

The retarded η → η′ phase transformation in Cu6Sn5 has become a potential risk to the service reliability of micro-solder joints. In this paper, both Cu6Sn5 crystal and powder samples were fabricated to explore the phase transformation behaviour of Cu6Sn5. Because of the difference in stress accumulation, η′ ↔ ηc ↔ η and η′ ↔ η phase transformations occurred in the Cu6Sn5 core layers and surface layers, respectively. Moreover, formation of the metastable intermediate ηc phase was confirmed to be both stress induced and structure dependent. In addition, by decreasing the crystal size or using a proper isothermal treatment, formation of the metastable phase in Cu6Sn5 can be significantly reduced. Our study can provide an understanding of the phase transformation behaviour of Cu6Sn5 and may provide visual data for solving the risk of retarded Cu6Sn5 phase transformation.

The wide usage of LiMn2O4 batteries makes it imperative that they be recovered and recycled. A novel efficient process of recycling was developed to recover spent LiMn2O4 batteries for regeneration of high-performance Li1.2[Mn0.56Ni0.16Co0.08]O2 cathode materials. The process comprises leaching and co-precipitation. The Li1.2[Mn0.56Ni0.16Co0.08]O2 cathode materials recovered showed promising electrochemical performance with discharge capacities of 239.4 mAh g−1 at 0.1 C in the voltage range of 2.5–4.6 V, and displayed perfect cyclic performance with 81.0% capacity retention after 100 cycles at 0.1 C. The results indicate that regeneration of high-performance Li1.2[Mn0.56Ni0.16Co0.08]O2 cathode materials is a promising strategy for recycling spent LiMn2O4 batteries.

Metal sulfides have been drawing more and more attention as electrode materials in batteries due to their high theoretical capacities. However, the volume expansion and loss of active materials are two major problems, hindering further improvement in their electrochemical performances. Herein, a strategy based on physical confinement/chemical adsorption is proposed to fabricate CoS and Co9S8 electrodes for advanced lithium batteries. Via a facile two-step method, porous C/CNT micro/nano-spheres embedding cobalt sulfide nanoparticles are successfully fabricated, in which sulfur is immobilized by C S bonds. Physically, the porous C/CNT micro/nano-spheres well accommodate the volume change and inhibit the loss of active materials. Chemically, the sulfur species are anchored by C S bonds to alleviate the migration and loss. Assembled as lithium battery anodes, the porous cobalt sulfide/carbon composites, particularly the CoS/C/CNT (CoS-0.4C) and Co9S8/C/CNT (Co9S8-0.8C), exhibit superior lithium storage properties to those without any complexing or any C S bonding. Furthermore, an in-situ electrochemical measurement is proposed to detect the existence of Li2S, which is helpful to understand the mechanism of conversion reaction-based metal sulfides.

Transition Metal Sulfides (TMSs) have received broadly research and application in the Lithium-ion Batteries (LIBs) field owing to their rare physical/chemical characteristics. Unfortunately, the fundamental flaws of volume expansion and poor electrical conductivity hampered its future practical implementation. Herein, a carbonization/activation procedure coupled with a facile solvothermal method and post-annealing strategy were developed to synthesize hollow tubular biomass-derived carbon (HBC) loaded NiS/C composite. The HBC serves a dual functional by providing highly active surface sites for NiS/C particles loading and naturally existing micron-level pores that can accommodate the volume variation. As a consequence, the HBC-NiS/C anode displayed strong lithium-ion storage performances with a high specific capacity (652 mAh g−1 at 0.2 A g−1 over 100 cycles), favorable rate capability, and exceptional structural durability.

Given the limitations inherent in current intercalation-based Li-ion batteries, much research attention has focused on potential successors to Li-ion batteries such as lithium-sulfur (Li-S) batteries and lithium-oxygen (Li-O2 ) batteries. In order to realize the potential of these batteries, the use of metallic lithium as the anode is essential. However, there are severe safety hazards associated with the growth of Li dendrites, and the formation of "dead Li" during cycles leads to the inevitable loss of active Li, which in the end is undoubtedly detrimental to the actual energy density of Li-metal batteries. For Li-metal batteries under practical conditions, a low negative/positive ratio (N/P ratio), a electrolyte/cathode ratio (E/C ratio) along with a high-voltage cathode is prerequisite. In this Review, we summarize the development of new electrolyte systems for Li-metal batteries under practical conditions, revisit the design criteria of advanced electrolytes for practical Li-metal batteries and provide perspectives on future development of electrolytes for practical Li-metal batteries.

The unstable electrode/electrolyte interface of the lithium metal anode is one of the reasons that induce the formation of lithium (Li) dendrites. The Li dendrites will reduce the coulombic efficiency, and even pierce the separator to cause the safety problems. Herein, a tightly bonded and uniformly distributed Cu

Sinomenine (SINO), which is used clinically to treat rheumatoid arthritis and neuralgia, is derived from the root and stems of Sinomenium acutum. SINO has been reported to exert analgesic, sedative and anti-inflammatory effects, and provides a protective role against shock and organ damage. Studies have suggested that SINO primarily exerts it anti-inflammatory function by inhibiting NF-κB signaling. There is also evidence to indicate that SINO may regulate inflammation Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) signaling. The present study aimed to investigate whether the anti-inflammatory and cerebral protective effects of SINO were induced through Nrf2 both in vitro and in vivo. The results revealed that SINO significantly upregulated Nrf2 protein expression levels, increased Nrf2 nuclear translocation and the upregulated the protein expression levels of downstream factors. The treatment of a middle cerebral artery occlusion model mice with SINO effectively reduced cerebral damage and inflammation, and restored the balance in cerebral oxidative stress. In addition, SINO treatment also promoted Nrf2-dependent microglia M1/M2 polarization and inhibited the phosphorylation of IκBα as well as NF-κB nuclear translocation. This revealed an important upstream event that contributed to its anti-inflammatory and cerebral tissue protective effects. In conclusion, the findings of the present study identified a novel pathway through which SINO may exert its anti-inflammatory and cerebral protective functions, and provided a molecular basis for the potential applications of SINO in the treatment of cerebral inflammatory disorders.

With wide application of electric vehicles and large-scale in energy storage systems, the requirement of secondary batteries with higher power density and better safety gets urgent. Owing to the merits of high theoretical capacity, relatively low cost and suitable discharge voltage, much attention has been paid to the transition metal sulfides. Recently, a large amount of research papers have reported about the application of transition metal sulfides in lithium ion batteries. However, the practical application of transition metal sulfides is still impeded by their fast capacity fading and poor rate performance. More well-focused researches should be operated towards the commercialization of transition metal sulfides in lithium ion batteries. In this review, recent development of using transition metal sulfides such as copper sulfides, molybdenum sulfides, cobalt sulfides, and iron sulfides as electrode materials for lithium ion batteries is presented. In addition, the electrochemical reaction mechanisms and synthetic strategy of transition metal sulfides are briefly summarized. The critical issues, challenges, and perspectives providing a further understanding of the associated electrochemical processes are also discussed.

The solution combustion synthesis (SCS) has been widely used to prepare varieties of materials, especially oxides. Nevertheless, there are just a few reports applying the SCS to synthesize sulfides, and most of them are prepared under the protection of an inert atmosphere. As the counterpart of metal oxides, the metal sulfides (MSs) also play an important role in energy-related devices. Herein, a novel air atmospheric SCS is proposed to prepare classes of MSs and the corresponding carbon composites. Thanks to the evaporation and flash burning of ethanol, the O2 is consumed, protecting the MSs and the carbon nanotubes (CNTs) from oxidation; thus, the mesoporous CoS, NiS, Cu2S, and the CoS/CNT, NiS/CNT, Cu2S/CNT, can be easily and rapidly obtained by directly combusting in the air atmosphere. Compared to the conventional SCS for synthesizing the MSs, the equipment requirements of this proposed method are low, which is suitable for large-scale preparation. The lithium storage properties of MSs and MSs/CNTs a...

The commercial applications of rechargeable magnesium batteries (RMBs) are hindered by the slow diffusion kinetic of Mg2+ ions in cathode materials. To overcome this problem, we design a new Na-Mg hybrid battery with the NaTi2(PO4)3@Carbon (NTP@C) nanoparticles as a cathode material, the Mg metal as an anode and the Mg(TFSI)2 + NaBH4 - triglyme/1,2-Dimethoxyethane (DME) as a hybrid electrolyte. For the first time, the Mg(TFSI)2 is applied as a Mg2+ ions source in the chlorine-free Na-Mg hybrid electrolyte with NaBH4 as both Na+ ions source and moisture scavenger. The NTP@C/Mg hybrid battery shows excellent electrochemical performance. The corresponding average capacity decay after 1000 cycles is only 0.004% and 0.008% per cycle at 2 C and 10 C, respectively. Even at 20 C, about 60 mAh g−1 can be obtained after 26000 cycles. The impressive capacity retention of 93.7% and 90.2% can be obtained at 5 and 10 C, respectively. The excellent electrochemical performance of the hybrid battery confirms the feasibility using Mg(TFSI)2 in the chlorine-free hybrid electrolyte for long term cycle. The developed NTP@C/Mg hybrid battery possesses the advantages of excellent electrochemical performances, good safety and low cost, making it promising for the commercial applications, especially for the large-scale energy storages.

Lithium sulfide (Li2S) cathode is considered as a prospective substitution for sulfur-based cathode for as its high specific capacity. Despite this, the poor electron and lithium ion transportation for Li2S impedes its further development. Herein, a great electron and lithium ion pathway is constructed for Li2S by a facile spray-dried technology. In this composite, the nano-sized Li2S is well imbedded in framework composed by the nitrogen/oxygen dual doped carbon nanotube/carbon (Li2S/CNT/C-N/O). The electrochemical tests show that the prepared Li2S/CNT/C-N/O cathode exhibits great cycling stability and rate capacity. A high initial discharge capacity of 1014 mAh g−1 is achieved with 671 mAh g−1 capacity remained at 200 mA g−1 after 200 cycles. Impressively, a stable capability is still exhibited from 200 to 3000 mA g−1 during rate testing. In-situ electrochemical impedance spectra test is further used to get insightful understanding about the improvements. The result reveals that decreased resistance and increased lithium-ion diffusion can be achieved for the Li2S/CNT/C-N/O, especially at the initial charging stage of polysulfides nucleation, which shed light on the improved reactive kinetics and active material utilization.

In this study, one-dimensional Cu2–xSe nanorods synthesized by a simple water evaporation-induced self-assembly approach are served as the anode material for Na-ion batteries for the first time. Cu2–xSe electrodes express outstanding electrochemical properties. The initial discharge capacity is 149.3 mA h g–1 at a current density of 100 mA g–1, and the discharge capacity can remain at 106.2 mA h g–1 after 400 cycles. Even at a high current density of 2000 mA g–1, the discharge capacity of the Cu2–xSe electrode still remains at 62.8 mA h g–1, showing excellent rate performance. Owing to the excellent electronic conductivity and one-dimensional structure of Cu2–xSe, the Cu2–xSe electrodes manifest fast Na+ ion diffusion rate. Moreover, detailed Na+ insertion/extraction mechanism is further investigated by ex situ measurements and theoretical calculations.