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N(6)-methyladenosine (m6A)-modified microRNAs (miRNAs) are relevant to cancer progression. Also, although the involvement of miR-380-3p in regulating cancer progression in bladder cancer and neuroblastoma has been preliminarily explored, its role in other types of cancer, such as pancreatic cancer (PC), has not been studied. Thus, this study aimed to investigate the role of miR-380-3p in regulating PC progression. Here, through performing Real-Time qPCR, we evidenced that miR-380-3p was significantly upregulated in the clinical pancreatic cancer tissues and cells compared to their normal counterparts. Interestingly, miR-380-3p was enriched with m6A modifications, and elimination of m6A modifications by deleting METTL3 and METTL14 synergistically suppressed miR-380-3p expressions in PC cells. Next, the gain and loss-of-function experiments verified that knockdown of miR-380-3p suppressed cell proliferation, epithelial-mesenchymal transition (EMT), and tumorigenesis in PC cells

Long non-coding RNAs (lncRNAs) may play a role in oxidative stress by altering the tumor microenvironment, thereby affecting pancreatic cancer progression. There is currently limited information on oxidative stress-related lncRNAs as novel prognostic markers of pancreatic cancer. Gene expression and clinical data of patients with pancreatic cancer were downloaded from The Cancer Genome Atlas (TCGA-PAAD) and the International Cancer Genome Consortium (ICGC-PACA) database. A weighted gene co-expression network analysis (WGCNA) was constructed to identify genes that were differentially expressed between normal and tumor samples. Based on the TCGA-PAAD cohort, a prediction model was established using lasso regression and Cox regression. The TCGA-PAAD and ICGC-PACA cohorts were used for internal and external validation, respectively. Furthermore, a nomogram based on clinical characteristics was used to predict mortality of patients. Differences in mutational status and tumor-infiltrating immune cells between risk subgroups were also explored and model-based lncRNAs were analyzed for potential immune-related therapeutic drugs. A prediction model for 6-lncRNA was established using lasso regression and Cox regression. Kaplan–Meier survival curves and receiver operating characteristic (ROC) curves indicated that patients with lower risk scores had a better prognosis. Combined with Cox regression analysis of clinical features, risk score was an independent factor predicting overall survival of patients with pancreatic cancer in both the TCGA-PAAD and ICGC-PACA cohorts. Mutation status and immune-related analysis indicated that the high-risk group had a significantly higher gene mutation rate and a higher possibility of immune escape, respectively. Furthermore, the model genes showed a strong correlation with immune-related therapeutic drugs. A pancreatic cancer prediction model based on oxidative stress-related lncRNA was established, which may be used as a biomarker related to the prognosis of pancreatic cancer to evaluate the prognosis of pancreatic cancer patients.

Developing large capacity electrode with fast charging capability has always been our goal for high-energy Li-ion batteries. To design a superior electrode, large enough capacity, suitable voltage plateau and good ionic/electronic conductivity need to be taken into account at the same time. Herein, by fusing the semiconductor Ge into nonmetal P, a novel metallic GexP60-x solid solution with wide range tuneable region is proposed, which is proved a kind of Ge-P binary alloy instead of typical ionic/covalent compound. The synthesized GexP60-x is not a metal phophide, which is in contradictory to our conventional view. Attributed from its unique phosphorus-like layered structure, those GexP60-x alloys possess a high conductivity (∼2.4 × 106 S/m). More specially, the Ge-P interaction is not a strong covalent bond like metal phosphides and thereby, the conversion reaction process based on chemical bond breaking in metal phosphides would not take place in those GexP60-x alloys, being replaced by alloying-type mechanism only. Therefore, such GexP60-x alloys are the first ones which can simultaneously exhibit both large capacity (>1800 mAh/g), unexpected high reversibility (ICE>90%) and suitable voltage plateau (∼0.5 V), delivering 770 mAh/g within 15 min with low yet safe voltage for fast-charging battery. This discovery that nonmetallic and semiconductor elements can form conductive alloys based on solid solution chemistry injects fresh blood into high-performanced anode families and offers a new strategy for material design toward advanced fast charging electrodes for energy storage.

Background: Long non-coding RNAs (lncRNAs) may play a role in oxidative stress by altering the tumor microenvironment, thereby affecting pancreatic cancer progression. There is currently limited information on oxidative stress-related lncRNAs as novel prognostic markers of pancreatic cancer. Materials and Methods: Gene expression and clinical data of patients with pancreatic cancer were downloaded from The Cancer Genome Atlas (TCGA-PAAD) and the International Cancer Genome Consortium (ICGC-PACA) database. A weighted gene co-expression network analysis (WGCNA) was constructed to identify genes that were differentially expressed between normal and tumor samples. Based on the TCGA-PAAD cohort, a prediction model was established using lasso regression and Cox regression. The TCGA-PAAD and ICGC-PACA cohorts were used for internal and external validation, respectively. Furthermore, a nomogram based on clinical characteristics was used to predict mortality of patients. Differences in mutational status and tumor-infiltrating immune cells between risk subgroups were also explored and model-based lncRNAs were analyzed for potential immune-related therapeutic drugs. Results: A prediction model for 6-lncRNA was established using lasso regression and Cox regression. Kaplan–Meier survival curves and receiver operating characteristic (ROC) curves indicated that patients with lower risk scores had a better prognosis. Combined with Cox regression analysis of clinical features, risk score was an independent factor predicting overall survival of patients with pancreatic cancer in both the TCGA-PAAD and ICGC-PACA cohorts. Mutation status and immune-related analysis indicated that the high-risk group had a significantly higher gene mutation rate and a higher possibility of immune escape, respectively. Furthermore, the model genes showed a strong correlation with immune-related therapeutic drugs. Conclusion: Based on oxidative stress-related lncRNAs, this study demonstrated that using WGCNA to identify prognosis-related genes and combining Cox and lasso regression analysis facilitated the establishment of a new signature that may more accurately and effectively predict the prognosis of patients with pancreatic cancer.

By introducing Li insufficiency, we interestingly found that m-LiBC exhibits a higher capacity (220 mA h g-1) than the original o-LiBC (50 mA h g-1). This improved capacity benefits from its structural evolution, with the interlayer rearrangement changed from "ABABAB" (o-LiBC) to "ABAABA" (m-LiBC) stacking, triggered by Li insufficiency. This understanding of interlayer rearrangement for LiBC may open a new avenue to activate Li+ extraction in other lithium compounds.

Manipulating the Li plating behavior remains a challenging task toward Li-based high-energy batteries. Generally, the Li plating process is kinetically controlled by ion transport, concentration gradient, local electric field, etc. A myriad of strategies have been developed for homogenizing the kinetics; however, such kinetics-controlled Li plating nature is barely changed. Herein, a ferroelectric substrate comprised of homogeneously distributed BaTiO

Mono- or few-layer black phosphorus (BP) has emerged as a promising photovoltaic and optoelectronic material with realistic applications subjected to instability and short charge carrier lifetime. Experiments show that covalent functionalization can improve the stability, but the underlying mechanism for the prolonged lifetime remains elusive. By performing spin-polarized time domain density functional theory combined with nonadiabatic (NA) molecular dynamics simulations, we demonstrate that BP passivated with both phenyl and nitrophenyl can suppress the nonradiative electron-hole recombination by a factor of 2 and 3, respectively, relative to the pristine system. The slow recombination is due to the interplay between energy gap, NA coupling, and decoherence time, which happens either through a hole-trap-assisted process or in a direct way between a free electron and hole in the spin-up channel. The observations hold in the spin-down channel. The study suggests that the passivating strategy should work for BP and other two-dimensional materials.

Many research efforts for advanced Li-ion batteries have been made to design new material with large capacity and long cycle life, but little attention has been paid to regulate the voltage platform until now. Although quite attractive for the binary Ge-based chalcogenides, challenge is that a large potential gap as well as incongruous reaction kinetics is typically found between their conversion step (>1.6 V) and alloying region (

Defect engineering is an important approach to enhancing the catalytic activity of a material, but there have been few reported controllable experiments due to the lack of systematic and comprehensive understanding of the effects of defects. For nanocarbon catalysts, it is still a challenge to prepare both atom-doped and defect-engineered catalysts with the desired more effective active centers, which requires an in-depth understanding of both experiment and theory. Herein, a topological rich-vacancy-defect nitrogen-doped nanocarbon (TRNC) material is constructed in situ via a simple magnesiothermic technology. It exhibits remarkable oxygen catalytic performance, which can be compared to the best metal-free bifunctional carbon electrocatalysts reported, even better than that of commercial noble-metal RuO2. Combined with density functional theory (DFT) calculations, the carbon vacancy defects with edge nitrogen doping as intrinsic active sites were found to exhibit excellent oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activity. When used practically as a catalyst in Li–O2 batteries, with a capacity restriction of 500 mA h g−1, it displays a long cycling and high rate durability of over 300 cycles at 200 mA g−1. This excellent performance arises from the three-dimensional topological rich-vacancy-defect nitrogen-doped nanocarbon. The effects of vacancy sites and nitrogen doping were probed via first-principles simulations to clarify the catalytic mechanisms which contribute to this superior performance.

Uncontrolled dendrite growth, continuous dead Li formation together with host-less volume changes associated with lithium metal greatly hamper the commercialization of high-energy-density lithium metal batteries (LMBs). Manipulating the deposition behavior of lithium ions is generally believed effective to root out undesired sharp protrusions over the anode surface and various kinds of 3D conductive inert substrates/hosts are introduced to mitigate volume changes and dead Li formation. However, the introduction of alien host would inevitably sacrifice partial energy density of cells. Herein, we successfully achieved in-situ deposition of a 3D continuous dendrite-free lithium deposition with blunt surface at the absence of inert host by simply adding an electrochemical active polymer-PMMA into the electrolyte to manipulate the deposition behavior of lithium ions. The function mechanism of PMMA upon Li deposition is investigated in detail. Upon discharging, lithium ions could react with PMMA and become immobilized. These pre-trapped lithium ions are then in-situ reduced into initial lithium seeds to guide sequential lithium deposition at the vicinity, ending up with a morphology modeled after the 3D PMMA molecular chains. Such morphology provides 3D continuous pathways for fast electron transport to eliminate dead Li formation without the help of foreign host. Li-LCO full cells equipped with such a 3D anode present greatly enhanced rate and cycle performance and highly preserved morphology upon rate testing and cycling.

he incidence of obesity and type 2 diabetes mellitus (T2DM) is increasing year by year and shows a trend towards younger age groups worldwide. It has become a disease that endangers the health of individuals all over the world. Among numerous weight loss surgeries, sleeve gastrectomy (SG) has become one of the most common surgical strategies for the treatment of T2DM. However, SG‑mediated alterations to the molecular mechanism of metabolism require further investigation. Thus, reverse transcription‑quantitative PCR was used to detect the expression levels of long non‑coding (lnc)RNA taurine‑upregulated gene 1 (TUG1), Sirtuin 1 (SIRT1), AMP‑activated protein kinase (AMPK) and uncoupling protein 2 (UCP2) in the serum of T2DM patients, as well as in HIEC‑6 and SW480 cells following treatment with high glucose and high fat (HGHF). Protein expression was detected by western blotting. Cell Counting Kit‑8 assays were performed to analyze cell viability, and flow cytometry and a TUNEL assay was performed to evaluate cell apoptosis. The secretion of ILs in the culture medium was detected by conducting ELISAs. The results showed that lncRNA TUG1 and UCP2 expression was upregulated, SIRT1 and AMPK expression levels were decreased by SG. Under HGHF conditions, HIEC‑6 and SW480 cell viability was inhibited, apoptosis was promoted, TUG1 expression was downregulated, and SIRT1 and AMPK expression levels were upregulated. The secretory levels of IL‑1β, IL‑6 and IL‑8 were increased, whereas the secretion of IL‑10 was decreased under HGHF conditions. lncRNA TUG1 overexpression significantly reversed the effects of HGHF on cell viability, apoptosis and SIRT1, AMPK, UCP2 and Bcl‑2 expression levels. Together, the findings of the present study demonstrated that lncRNA TUG1 alleviated the damage induced by HGHF in intestinal epithelial cells by downregulating SIRT1 and AMPK expression, and upregulating UCP2 expression. Thus, the lncRNA TUG1/AMPK/SIRT1/UCP2 axis may serve an important role in the treatment of T2DM.

Button mushroom (Agaricus bisporus) is widely marketed all over the world due to its good flavor quality and high nutritional value. However, the perishable characteristics decrease the physicochemical quality and change the flavor profile, affecting consumer purchase. In this study, button mushrooms were separately stored in the package with 0, 2, 4, 8, 16 perforations for 8 d at 10 °C and whether the micro-perforated film packing delay button mushrooms the changes of physicochemical quality and volatile profile was investigated. The results showed that 0 perforation package could maintain the weight and firmness of button mushrooms. Micro-perforated film packing was found effective to decrease the browning index of button mushrooms during shelf-life. In addition, micro-perforation film packing had a lower concentration of 3 off-flavor compounds (2-methylbutanal, 3-methylbutanal and ethanol) and a higher concentration of 13 mushroom characteristic flavor compounds than that in button mushrooms-packed 0 perforation film when stored for 8 d. The 8 perforations groups had the most varieties of aroma impact compounds (odor active values, OAV≥1), which contributed to the flavor profile of button mushrooms. Furthermore, it is concluded that 8 perforations groups could create an atmosphere condition to maintain the physiology quality and volatile profile of button mushrooms during shelf-life.

Surface electronic structures of the photoelectrodes determine the activity and efficiency of the photoelectrochemical water splitting, but the controls of their surface structures and interfacial chemical reactions remain challenging. Here, we use ferroelectric BiFeO3 as a model system to demonstrate an efficient and controllable water splitting reaction by large-area constructing the hydroxyls-bonded surface. The up-shift of band edge positions at this surface enables and enhances the interfacial holes and electrons transfer through the hydroxyl-active-sites, leading to simultaneously enhanced oxygen and hydrogen evolutions. Furthermore, printing of ferroelectric super-domains with microscale checkboard up/down electric fields separates the distribution of reduction/oxidation catalytic sites, enhancing the charge separation and giving rise to an order of magnitude increase of the photocurrent. This large-area printable ferroelectric surface and super-domains offer an alternative platform for controllable and high-efficient photocatalysis.

Mixed anatase/rutile TiO

Research Highlights: This study is the first to examine the genetic diversity of Michelia shiluensis (Magnoliaceae). High genetic diversity and low differentiation were detected in this species. Based on these results, we discuss feasible protection measures to provide a basis for the conservation and utilization of M. shiluensis. Background and Objectives: Michelia shiluensis is distributed in Hainan and Guangdong province, China. Due to human disturbance, the population has decreased sharply, and there is thus an urgent need to evaluate genetic variation within this species in order to identify an optimal conservation strategy. Materials and Methods: In this study, we used eight nuclear single sequence repeat (nSSR) markers and two chloroplast DNA (cpDNA) markers to assess the genetic diversity, population structure, and dynamics of 78 samples collected from six populations. Results: The results showed that the average observed heterozygosity (Ho), expected heterozygosity (He), and percentage of polymorphic loci (PPL) from nSSR markers in each population of M. shiluensis were 0.686, 0.718, and 97.92%, respectively. For cpDNA markers, the overall haplotype diversity (Hd) was 0.674, and the nucleotide diversity was 0.220. Analysis of markers showed that the genetic variation between populations was much lower based on nSSR than on cpDNA (10.18% and 77.56%, respectively, based on an analysis of molecular variance (AMOVA)). Analysis of the population structure based on the two markers shows that one of the populations (DL) is very different from the other five. Conclusions: High genetic diversity and low population differentiation of M. shiluensis might be the result of rich ancestral genetic variation. The current decline in population may therefore be due to human disturbance rather than to inbreeding or genetic drift. Management and conservation strategies should focus on maintaining the genetic diversity in situ, and on the cultivation of seedlings ex-situ for transplanting back to their original habitat.

Many recent efforts on the electrode design for advanced Li-ion batteries (LIBs) are often devoted to increasing the gravimetric capacity, but little attention is paid to the volumetric capacity which is more critical for practical application. Though the alloying-type anode materials are quite attractive, the challenge is that they must be composited with a large amount of carbon materials (e.g., GO, rGO, CNT) to buffer their large volume change, which would undoubtedly sacrifice the volumetric energy density of the whole electrode due to the carbon's low tap density (∼0.05 g/cm

TiO2 is an excellent photocatalytic and photovoltaic material but suffers low efficiency because of deep trap states giving rise to fast charge and energy losses. Using a combination of time-domain density functional theory and nonadiabatic molecular dynamics, we demonstrate that grain boundaries (GBs), which are common in polycrystalline TiO2, accelerate nonradiative electron-hole recombination by a factor of 3. Despite GBs increase the band gap without creating deep trap states, and accelerate coherence loss, they enhance nonadiabatic electron-phonon coupling, and facilitate the relaxation. Importantly, electrons accumulated at the boundaries together with the relatively long-lived excite state favor photocatalytic reaction. Our study rationalizes the experimental observations and provides valuable perspectives for improving the device performance by defect engineering.

Compared with elemental phosphorus, GeP5, with much better thermostability and super higher conductivity, can exhibit a comparable capacity (>2000 mA h g–1) with a much higher first Coulombic efficiency (95%) for lithium-ion batteries. However, such high capacity is accompanied by large volume expansions, leading to fast capacity fading. To improve the cycle stability, fabricating a special nanostructure to reduce the volume stress and compositing with a carbon matrix to buffer the volume change are highly required. However, nanostructured metal phosphides were rarely reported up to now because they are difficult to be synthesized via a normal wet chemistry method or gas phosphorization because of lack of proper reactants and poor thermostability of phosphides. Herein, we successfully achieve uniform carbon-encapsulated GeP5 nanofibers (GeP5@C-NF) by processing GeP5 nanoparticles into carbon nanofibers via electrospinning. After carbon encapsulation, the thermostability of GeP5 can be greatly improved to ...

Two-dimensional transition metal dichalcogenides (TMDs), such as WS2, are appealing candidates for optoelectronics and photovoltaics. The strong Coulomb interaction in TMDs is however known to prevent electron–hole pairs from dissociating into free electron and hole. The experiment demonstrates that combination of WS2 and quantum dots (QDs) can achieve efficient charge separation and enhance photon-to-electron conversion efficiency. Using real-time time-dependent density functional theory combined with nonadiabatic molecular dynamics, we model electron and hole transfer dynamics at a WS2/QD heterojunction. We demonstrate that both electron and hole transfer are ultrafast due to strong donor–acceptor coupling. The photoexcitation of the WS2 leads to a 75 fs electron transfer, followed by a 0.45 eV loss within 90 fs. The photoexcitation of QD results in 240 fs hole transfer, but loses only 0.15 eV of energy within 1 ps. The strong charge–phonon coupling and a broad range of phonon modes involved in electron...

Antimony (Sb) shows high conductivity and reactivity not only with lithium ions, but also with sodium ions due to its unique puckered layer structure; also, it can deliver a high theoretical capacity of 660 mA h g−1 by forming Li3Sb or Na3Sb. Compared with graphite, Sb has much higher theoretical capacity and safer reaction potential; moreover, it has a simpler reaction process and smaller volume changes than Si, Ge and Sn. In this study, the recent progress of Sb-based materials including elemental Sb nano-structures, intermetallic Sb alloys and Sb chalcogenides for lithium-ion and sodium-ion batteries are introduced in detail along with their electrode mechanisms, synthesis, design strategies and electrochemical performance. This review aims to present a full scope of the structures and properties of Sb-based materials and highlight effective strategies to design high performance Sb-based anode materials in the field of rechargeable Li/Na ion batteries.

Layered TiS3 materials hold appealing potential in photovoltaics and optoelectronics due to their excellent electronic and optical properties. Using time-domain density functional theory combined nonadiabatic (NA) molecular dynamics, we show that the electron-hole recombination in pristine TiS3 nanoribbons (NRs) occurs on tens of picoseconds and is over 10-fold faster than the experimental value. By performing an atomistic ab initio simulation with a sulfur vacancy, we demonstrate that sulfur vacancy greatly reduces electron-hole recombination, achieving good agreement with experiment. Introduction of sulfur vacancy increases the bandgap slightly because the NRs highest occupied molecular orbital is lowered in energy. More importantly, sulfur vacancy diminishes partially electron and hole wave functions overlap and reduces NA electron-phonon coupling, which competes successfully with the longer decoherence time, slowing down recombination. Our study suggests that rational choice of defects can control non...

To realize the full potential of transition metal dichalcogenides interfaced with bulk semiconductors for solar energy applications, fast photoinduced charge separation, and slow electron–hole recombination are needed. Using a combination of time-domain density functional theory with nonadiabatic molecular dynamics, we demonstrate that the key features of the electron transfer (ET), energy relaxation and electron–hole recombination in a MoS2–TiO2 system are governed by the weak van der Waals interfacial interaction and interface polarization. Electric fields formed at the interface allow charge separation to happen already during the photoexcitation process. Those electrons that still reside inside MoS2, transfer into TiO2 slowly and by the nonadiabatic mechanism, due to weak donor–acceptor coupling. The ET time depends on excitation energy, because the TiO2 state density grows with energy, increasing the nonadiabatic transfer rate, and because MoS2 sulfur atoms start to contribute to the photoexcited sta...

The low electronic conductivity and the sluggish sodium-ion diffusion in the compact crystal structure of Ti-based anodes seriously restrict their development in sodium-ion batteries. In this study, a new hollandite KxTiO2 with large (2 × 2) tunnels is synthesized by a facile carbothermal reduction method, and its sodium storage performance is investigated. X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses illustrate the formation mechanism of the hollandite KxTiO2 upon the carbothermal reduction process. Compared to the traditional layered or small (1 × 1) tunnel-type Ti-based materials, the hollandite KxTiO2 with large (2 × 2) tunnels may accommodate more sodium ions and facilitate the Na+ diffusion in the structure; thus, it is expected to get a large capacity and realize high rate capability. The synthesized KxTiO2 with large (2 × 2) tunnels shows a stable reversible capacity of 131 mAh g–1 (nearly 3 times of (1 × 1) tunnel-structured Na2Ti6O13) and superior cycling stability...

Sodium ion batteries (SIBs) are considered to be a promising alternative to lithium ion batteries because of the high abundance of sodium. However, the scarcities of suitable anode materials severely hamper the development of SIBs. Here, we synthesized a GeP5/C composite with binary sodium-reactive components on a large scale. Theoretically, it can promise a capacity of 1888 mA h g−1 or 6891 mA h cm−3, which is the best record in anodes for SIBs reported so far. In practice, the GeP5/C showed a low potential of ≈0.4 V vs. Na+/Na with a smooth charge/discharge profile. It delivered a large reversible capacity of 1250 mA h g−1 with a first coulombic efficiency of 93%. Electrochemical-mechanism studies suggested that the formation of a GeP5 phase endowed a high first coulombic efficiency and synergetic effect between the sodiation of Ge and P. This effect smoothly leveled the multistep plateaus and effectively reduced the polarization between charge/discharge. When applied to a full cell by coupling a Na3V2(PO4)3/C cathode, the assembled Na3V2(PO4)3//GeP5 full cell showed a large capacity of 800 mA h g−1 with a high average output voltage of 2.65 V. The excellent sodium-storage performances of GeP5/C will ensure commercial utilization in future SIBs.

GeS with a layered structure is expected to be a promising anode material for lithium ion batteries by the theoretical prediction of its excellent ion intercalation response. However, its experimental investigation is limited because of its low yield and complicated synthesis procedure. In this work, we successfully synthesize pure GeS and its carbon composite on a large scale by a simple and facile ball milling method. When serving as a novel anode material, GeS/C delivers a high reversible capacity of 1768 mA h g−1 with a high initial coulombic efficiency of 94% for lithium-ion batteries. The ex situ XRD patterns and CV tests confirm that GeS undergoes firstly a conversion reaction followed by an alloying type of lithium storage mechanism, in which the electrochemical performance controlled within the alloying reaction region is very stable and highly reversible, with a low and safe potential of 0.35 V vs. Li+/Li. When further applied in a full cell by coupling commercial LiCoO2 as the cathode, the assembled LiCoO2//GeS full cell can offer a high capacity of 736 mA h g−1, with a high flat discharge plateau of 3.4 V, showing a high utilization efficiency of the GeS anode. These results demonstrate that the layered GeS is a potential anode for high-energy lithium-ion batteries.

Nanostructures have been proved to be a promising strategy to realize fast Na-ion diffusion and high electrochemical activity for sodium titanate anodes. However, most researchers pay their attention to the controllable synthesis of nano-morphology for sodium titanate; there are few reports on the existence of water molecules and their influence on the structure and electrochemical performance of these solution-synthesized sodium titanate electrodes. Herein, urchin-like layered sodium titanate ultrafine nanowires are synthesized and the existence of structural water in them is confirmed. Their structural evolution upon the removal of water is investigated by SEM, XRD, TEM, IR and Raman measurements. The departure of interlayer water not only leads to a morphology change from ultrafine nanowires to highly crystalline nanorods but also induces a structure transformation from layered NaTi3O6(OH)·2H2O into tunnel structured Na2Ti6O13. The electrochemical analysis confirms that the dehydrated sample exhibits a better rate capability and enhanced cycling performance, suggesting that the existence of interlayer water in sodium titanate is unfavourable for the sodium ion diffusion in TiO6 octahedral layers. Our findings give a new understanding of the design and synthesis of the sodium titanate nanostructure with high rate capability.

The dendritic lithium formation and sustained lithium consumption caused by the uncontrollable side reactions between lithium and electrolytes seriously restrict the applications of lithium anodes in high-energy density batteries, especially in carbonate electrolytes. Ameliorating the surface status of lithium anodes is critical for modulating lithium deposition behavior and improving the cycling stability of lithium metal batteries. Herein, magnesium chloride salt is first reported as a carbonate electrolyte additive for lithium surface modification by in situ reaction. It is proved that both Cl– and Mg2+ play important roles in building a stable electrode/electrolyte interface with a fast Li+ diffusion property. The coexistence of inorganic LiCl and metallic Mg species in the interface can effectively decrease the surface side reactions, lower interphase resistance, promote Li ions diffusion, and result in uniform lithium deposition. The electrochemical tests show that the reversible utilization rate of...