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[Display omitted] Biochar is regarded as a promising lithium-ion batteries anode material, owing to its high cost-effectiveness. However, the poor specific capacity and cycling stability have limited its practical applications. A straightforward and cost-efficient solvothermal method is presented for synthesizing Mn 3 O 4 /biochar composites in this study. By adjusting solvothermal temperatures, Mn 3 O 4 with different morphology is prepared and anchored on the biochar surface (MKAC-T) to improve the electrochemical performance. Due to the morphological effect of nanospherical Mn 3 O 4 on the biochar surface, the MKAC-180 anode material demonstrates outstanding reversible capacity (992.5 mAh/g at 0.2 A/g), significant initial coulombic efficiency (61.1 %), stable cycling life (605.3 mAh/g at 1.0 A/g after 1000 cycles), and excellent rate performance (385.8 mAh/g at 1.6 A/g). Moreover, electro-kinetic analysis and ex-situ physicochemical characterizations are employed to illustrate the charge storage mechanisms of MKAC-180 anode. This study provides valuable insights into the "structure–activity relationship" between Mn 3 O 4 microstructure and electrochemical performance for the Mn 3 O 4 /biochar composites, illuminating the industrial utilization of biomass carbon anode materials. [ABSTRACT FROM AUTHOR]

The emerging market of high-power lithium-ion batteries (LIBs) highlights the importance of developing high-voltage cathodes. Lithium nickel phosphate (LiNiPO 4) with the highest theoretical discharge potential (∼5.1V) has attracted increasing attention due to its stable olivine structure. In this study, ultrathin carbon layer-coated LiNiPO 4 was synthesized using oleylamine-assisted solvothermal method under different solvothermal times, and the effect of solvothermal time (1h–18h) on LiNiPO 4 samples is fully investigated. X-ray diffraction (XRD) shows that high-purity LiNiPO 4 materials can be prepared after calcination of the solvothermal product under N 2 , but adding part of H 2 to the calcination atmosphere will lead to the generation of impurities in the target product. As the solvothermal time increases, the product will agglomerate and grow, the particle size will increase, and the morphology will change from nanoparticle to rodlike structure. After the high-temperature calcination step, the oleylamine is completely carbonized, and a conductive carbon layer is successfully coated on the LiNiPO 4 with the thickness of 2 nm. As the solvothermal time increases, the graphitization degree of oleylamine increases after carbonization. The existence of the carbon layer and the increase in the degree of graphitization are beneficial to improving the electrical conductivity and Li-ion diffusion rate of LiNiPO 4. The initial discharge capacity of LNP@C-12h product prepared with 12 h solvothermal time is 35 mA h g−1 at 0.1 C. Rietveld analysis shows that the anti-site defect concentration of the LNP@C material is 1.07 %, and the proportion increases to 2.83 % after several cycles. This work provides a positive contribution to the synthesis and modification of high-voltage LiNiPO 4 materials and explains the electrochemical performance degradation of LiNiPO 4 from the perspective of increasing the concentration of anti-site defects. • The core-shell carbon-coated LiNiPO 4 is synthesized. • The pure phase LiNiPO 4 is prepared by adjusting the calcination atmosphere. • Uniformly distributed nanostructured LiNiPO 4 is prepared. [ABSTRACT FROM AUTHOR]

Lithium titanate (LTO) anode has Receded extensive attention due to IS high safety and long cycle life. Here, S atoms was doped into LTO as an anode material for lithium ion batteries by solvothermal method, and IS electrochemical properties were investigated. The X-ray diffraction (XRD) results showed that the introduced S atoms replaced Ti4+, which increased the late volume and conductivity of LTO. Scanning electron microscopy (SEM) results showed that the LTO particle size was reduced due to the interference of S atoms on the crystal growth of LTO. The rate performance of sulfur-doped LTO (S-LTO) was investigated by charge- discharge tests, and the results showed that S-LT()-1.5 had the best performance, exhibiting 143.8 mA • h/g at 20 C and still having 137.4 mA • h/g after 1000 cycles. The results of electrochemical impedance (EIS), cyclic voltammetry (CV) and galvanostatic intermittent titration technique (GITT) showed that the increased lattice volume and conductivity promoted the movement of Li+ and electrons in S-LTO-1.5, reduced the polarization, and thus enhanced electrochemical properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mn 2 V 2 O 7 microspheres with solid or hollow interiors were realized via a facile solvothermal method followed by annealing. • The effects of PVP as controlling agent on the structure and electrochemical properties of Mn 2 V 2 O 7 were revealed. • Mn 2 V 2 O 7 microspheres demonstrated superior lithium storage performance owing to the favorable structure. We report the fabrication of well-defined phase-pure Mn 2 V 2 O 7 hollow microspheres (h-MVO), assembled from the porous plate-like building blocks, via a facile solvothermal method followed by annealing, with the assistance of polyvinylpyrrolidone (PVP) as the structure-regulating agent. The microstructure dependent electrochemical properties of h-MVO as anode materials for lithium ion batteries (LIBs) are investigated, and excellent lithium storage performance is obtained with a reversible capacity of 1707 mAh g−1 after 700 cycles at 0.5 A g−1, revealing that the unique hierarchical framework of the h-MVO microspheres with hollow interiors and porous building blocks could not only accelerate the transport of Li+ ions and electrolyte, but also efficiently suppress the electrode pulverization upon cycling. More importantly, we demonstrate that PVP can be an effective agent to tune the microstructures, which would be promising for the development of high-performance energy storage devices. [ABSTRACT FROM AUTHOR]

Summary: Transition metal carbonates (TMCs) as high‐performance anode materials for lithium‐ion batteries (LIBs) have attracted intensive research interests in recent years. Nanostructures with abundant pore channels can well address the volume change during the Li+ insertion/desertion process and shorten the ionic diffusion length. Multi‐component carbonates with excellent porous structures exhibit enhanced electrochemical performance in contrast to the mono‐component carbonates due to the synergistic effect among multi‐metal elements. Herein, we used a simple solvothermal method to synthesize Co‐based solid‐solution carbonates CoxNi1−xCO3 to obtain different microstructures by changing the content of the precipitant. The optimized solid‐solution Co2/3Ni1/3CO3 (CNCO‐20) delivers a high initial Coulombic efficiency of 83%, a reversible high‐rate capacity of 828.1 mAh g−1 at 2.0 A g−1, and good electrochemical stability with a reversible capacity of 740.9 mAh g−1 after 500 charge‐discharge cycles at 1.0 A g−1 due to the enhanced electronic/ionic transport, sufficient electroactive sites, and improved electrochemical stabilities. Considering the excellent specific capacity and long life‐span, the synthesized solid‐solution CNCO‐20 demonstrate great promise as an alternative anode electrode material compared to conventional materials for LIBs. [ABSTRACT FROM AUTHOR]

Advanced cathode materials for high power and great cycle stability have attracted much attention. Layer-structured NH4V3O8 (NVO) has been intensively studied because by their large distance between the layers and high discharge capacity. Nevertheless, the cycling stability of NVO is seriously restrained by the low electrical conductivity and poor lithium-ion diffusion ability. In this research, reduced graphene oxide nanosheets decorated carbon-coated NH4V3O8 (G-NVO@C) were synthesized through a facile one-step solvothermal method. As the cathode material for lithium-ion batteries, the G-NVO@C electrode exhibits outstanding cycling stability. The first discharge capacity is 220.6 mAh g−1 at a current density of 15 mA g−1. After 200 cycles, the discharge capacity is still maintained as high as 172.6 mAh g−1, and a retention of 78.2% was achieved. It is noteworthy that the specific discharge capacity decreased rapidly only in the first five cycles and then stabilized. These characteristics indicate that the G-NVO@C electrode has a broad application as cathode material for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Transition metal phosphides are emerging as potential anode materials for lithium‐ion batteries (LIBs) due to their high theoretical capacity and good thermal stability, but the severe volume changes during the charge/discharge process and low electrical conductivity have hampered their practical application. Herein, the facile synthesis of carbon‐coated CoP nanoparticles (CoP@C) with uniform spherical morphology is demonstrated through the solvothermal method followed by annealing and phosphating treatments, in which an interesting precursor, the Co–gluconate complex, is prepared as the Co/C sources. When used as the LIB anode, the CoP@C electrode displays excellent cycling stability with a reversible capacity of 483.4 mA h g−1 upon 1000 cycles at 0.5 A g−1. The superior lithium storage performance is attributed to the unique composite structure of CoP@C with the nanosized CoP particles wrapped into the carbon matrices, which can enhance the electrical conductivity, provide sufficient reaction sites, shorten the Li+ transport path, and buffer the volume changes of the electrode upon lithiation/delithiation. More importantly, the strategy of generating gluconate–metal complex as the metal‐ and carbon‐containing precursor can be widely applied in the synthesis of various functional materials for energy‐related applications. [ABSTRACT FROM AUTHOR]

Summary Recently, binder‐free nanostructured materials provide a great opportunity for advanced lithium‐ion batteries (LIBs) owing to their improved electrical conductivity with good porous structure. NiCo2O4 (NCO) nanostructures were successfully deposited on copper foam (CF) substrate to form porous three‐dimensional (3D) NCO@CF hybrid structures via a simple solvothermal synthesis, followed by further heat treatment at 300°C (designated as NCO@CF‐300) and 400°C (NCO@CF‐400). The as‐prepared samples revealed distinctly mixed morphologies of 2D nanosphere and nanowire‐like structures, tuned by the further heat treatment. Both the electrodes could be explored as a binder‐free anode for next‐generation LIBs. It is demonstrated that the good integration of 2D morphology of NCO with 3D architectured CF has a significant effect on its electrochemical results. For the first cycle, binder‐free NCO@CF‐300 and NCO@CF‐400 electrodes delivered the discharge capacity values of 1946 and 2637 mA h g−1, respectively, at 500 mA g−1. Moreover, the NCO@CF‐300 electrode exhibited stable reversible capacity and good rate capability. From these results, the growth of NCO nanostructures on the CF can be suggested as a potential anode material for high‐performance Li‐ion batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • LiFePO 4 with various morphologies was tunable synthesized using phytic acid. • The material with hierarchical structure exhibited outstanding electrochemical performance. • The reaction mechanism was proposed through time-dependent experiments. • The mechanism will provide a new development for preparing electrode materials. LiFePO 4 has been widely considered as a promising cathode material for lithium ion batteries because of its nontoxicity, high specific capacity, good safety characteristics and low cost. However, the actual fabrication of LiFePO 4 typically uses LiH 2 PO 4 , NH 4 H 2 PO 4 or H 3 PO 4 as phosphorus sources, possibly leading to the corrosion of the experimental facilities and release of toxic gas during the synthesis process. Hence, we use phytic acid (PhyA) as a new eco-friendly and sustainable phosphorus source to synthesize LiFePO 4. Results show that the reaction time and temperature have significant effects on the morphology. LiFePO 4 prepared at 180 °C for 4 h (LFP-4) shows unique hierarchical structure and exhibits best electrochemical performance over a wide test temperature (25–55 °C). Through time-dependent experiments to explore the reaction mechanism of LiFePO 4 , it is found that an intermediate Fe 3 (PO 4) 2 is produced that acts as the substrate for the subsequent preparation of LiFePO 4. After carbon coating, LFP/C-4 (after carbon coating, LFP-4 labeled as LFP/C-4) shows an outstanding initial discharge capacity (156.9 mAh g−1, 1C at 25 °C) and high temperature behavior (147.1 and 126.8 mAh g−1 at 1C and 2C under 55 °C). This result is highly important for the controllable synthesis and improvement of electrochemical characteristics of LiFePO 4 cathode material. [ABSTRACT FROM AUTHOR]

Poor electrochemical kinetics caused by the unstable structure for the dramatically volumetric expansion (>300%) hinders the application of silicon in rechargeable lithium ion batteries. Si@C-Ni-MOF composites with petal-like Ni-MOFs as the skeleton and Si@C nanoparticles as the active center were synthesized via facile solvothermal process. The resulting Ni-MOF-Si@C material maintains admirable stability on cycling, and its capacity remains 1545.3 mAh g−1 with a high capacity retention rate of 99.79% after 300 cycles at the current density of 200 mA g−1. The enhancement on the kinetics is obtained, attributing to the porous structure created by the petal-like Ni-MOFs and the strong interface bonding between Si@C and Ni-MOFs. [ABSTRACT FROM AUTHOR]

The ZnS/C composites with different carbon coating contents were successfully prepared using the solvothermal method followed by the calcination process. The obtained ZnS/C composites were characterized by XRD, SEM, and TEM. The results indicate that the morphology of 50 wt% carbon-coated ZnS/C composites possesses uniform spheres with a size of 80 nm, and the thickness of the carbon layer is 8 nm. When the prepared composites were used as anode materials for lithium-ion batteries (LIBs), the electrode made by 50 wt% carbon-coated ZnS/C composites shows an excellent initial discharge capacity of 1189.8 mAh/g, high discharge capacity of 948.9 mAh/g at a current rate of 0.1 C after 50 cycles, good cycling stability, and excellent rate capability of 744.8 mAh/g at 2.0 C. The excellent electrochemical performances make the nanosized ZnS/C composites a promising candidate for the LIBs. [ABSTRACT FROM AUTHOR]

Cu2SnS3, as a modified material for high-capacity tin-based anodes, has great potential for lithium-ion battery applications. The solvothermal method is simple, convenient, cost-effective, and easy to scale up, and has thus been widely used for the preparation of nanocrystals. In this work, Cu2SnS3 nanoparticles were prepared by the solvothermal method. The effects of high-temperature annealing on the morphology, crystal structure, and electrochemical performance of a Cu2SnS3 nano-anode were studied. The experimental results indicate that high-temperature annealing improves the electrochemical performance of Cu2SnS3, resulting in higher initial coulombic efficiency and improved cycling and rate characteristics compared with those of the as-prepared sample. [ABSTRACT FROM AUTHOR]

V2O3 is considered to be a potential anode material due to its large specific capacity and rich resources. Herein, flock‐like V2O3 coated with carbon is prepared through a facile and simple solvothermal method followed by annealing at a relatively low temperature. The structure of V2O3/C is composed of porous strips. Due to the unique morphology and structure, the V2O3/C anode material shows excellent electrochemical performance. It delivers a specific discharge capacity of 696 mAh g−1 after 100 cycles, which is 95% of the specific discharge capacity (732 mAh g−1) after the sixth cycle. The V2O3/C anode material annealed at 360 °C (V2O3/C‐360) delivers 601 mAh g−1 at a current density of 300 mA g−1 after 500 cycles. It implies superior cyclic stability of V2O3/C‐360. In addition, the anode also shows excellent rate capability. Specific capacities of approximately 600, 420, and 300 mAh g−1 are obtained at the current densities of 0.3, 2, and 5 A g−1, respectively. The large current contribution of the capacitive reveals favorable superior lithium storage kinetics. This anode material presents great application potential in high‐performance lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

• The results show that the time and temperature of solvent-thermal reaction have significant effects on the morphology, size and orientation of LiMnPO4 crystals. • The discharge capacity of the optimal sample at 0.1C and 1C is 145.1 mAh/g and 90.4 mAh/g, respectively. • The improvement in electrochemical performance can be attributed to the synergistic effect of nanoscaling and crystal plane exposure, particularly the excessive exposure of the (2 0 0) crystal plane. Inspired by the successful commercialization of LiFePO 4 , LiMnPO 4 with a similar olivine structure has gained extensive research attention due to its higher electrode potential. Among various modification methods, nanoscaling and exposure of active crystal facets have been proven effective in improving the intrinsic issues of LiMnPO 4. In this study, LiMnPO 4 /C nanocrystals were synthesized using ethylene glycol as a solvent, and the reaction temperature and time of the solvent thermal process were varied. It was found that the sample synthesized at a reaction temperature of 200 °C and a reaction time of 9 h exhibited discharge capacities of 145.1 mAh/g and 63.9 mAh/g at 0.1C and 5C, respectively. Furthermore, after 100 cycles, the sample maintained a capacity retention rate of 92.1 %. This significant improvement in electrochemical performance was attributed to the synergistic effect of nanoscaling and crystal facet engineering, effectively addressing the low electronic conductivity and sluggish diffusion rate issues of LiMnPO 4 for lithium ions. [ABSTRACT FROM AUTHOR]

Ni-rich cathode LiNixCoyMn1-x-yO2 (NCM, x ≥ 0.5) materials are promising cathodes for lithium-ion batteries due to their high energy density and low cost. However, several issues, such as their complex preparation and electrochemical instability have hindered their commercial application. Herein, a simple solvothermal method combined with calcination was employed to synthesize LiNi0.6Co0.2Mn0.2O2 with micron-sized monodisperse particles, and the influence of the sintering temperature on the structures, morphologies, and electrochemical properties was investigated. The material sintered at 800 °C formed micron-sized particles with monodisperse characteristics, and a well-order layered structure. When charged–discharged in the voltage range of 2.8–4.3 V, it delivered an initial discharge capacity of 175.5 mAh g−1 with a Coulombic efficiency of 80.3% at 0.1 C, and a superior discharge capacity of 135.4 mAh g−1 with a capacity retention of 84.4% after 100 cycles at 1 C. The reliable electrochemical performance is probably attributable to the micron-sized monodisperse particles, which ensured stable crystal structure and fewer side reactions. This work is expected to provide a facile approach to preparing monodisperse particles of different scales, and improve the performance of Ni-rich NCM or other cathode materials for lithium-ion batteries.

Olivine-type LiFe x Mn 1- x PO 4 /C cathode materials are of great interest for lithium-ion batteries because of their higher lithium ion intercalation potential compared with that of LiFePO 4. Two types of LiFe 0.5 Mn 0.5 PO 4 /C nanorods with different sizes and crystal structures were synthesized through a facile glycol-based solvothermal process with different precursor feeding sequences. The microstructural investigation revealed that the size and structure of the LiFe 0.5 Mn 0.5 PO 4 nanorods can be tuned by nucleation and crystal growth rates of the intermediate precipitates, which can be controlled by precursor feeding sequence. The LiFe 0.5 Mn 0.5 PO 4 nanorods obtained through the first feeding sequence (a solution of transition metal salts was added dropwise into the solution mixture of LiOH and H 3 PO 4) exhibited less exposure of the (010) crystal faces and had bigger sizes compared with those of the LiFe 0.5 Mn 0.5 PO 4 nanorods obtained through the second feeding sequence (a LiOH solution was added dropwise into the solution mixture of H 3 PO 4 and transition metal salts). Electrochemical investigations indicated that the LiFe 0.5 Mn 0.5 PO 4 nanorods obtained through the second feeding sequence showed substantially improved electrochemical performance, in which the discharge capacities reached 157 and 119 mAh g−1 at 0.2 and 5 C, respectively. Furthermore, a capacity retention of 89% was obtained after 500 cycles at 1 C, demonstrating excellent cyclic stability. Image 1 • LiFe 0.5 Mn 0.5 PO 4 /C nanorods with large exposed (010) faces have been synthesized. • Fast precipitation causes formation of LiFe 0.5 Mn 0.5 PO 4 nanorods with fine sizes. • They show a high cyclic capacity, high stability and high intercalation potential. • Reversible capacity reaches 157 and 119 mAh g−1 at 0.2 and 5 C, respectively. [ABSTRACT FROM AUTHOR]

Highlights • Nickel-cobalt microsphere precursor with mesoporous structure and fine size is synthesized via solvothermal routine. • LiNi 0.88 Co 0.12 O 2 inherits the fine size and particles integrity of nickel-cobalt microsphere precursor. • LiNi 0.88 Co 0.12 O 2 delivers a capacity of 170.5 mAh·g−1 at 4 C after 50 cycles. Abstract At present, the chemical co-precipitation dominates the synthesis pathway of LiNiO 2 -based cathode material for lithium ion batteries (LIBs). Compared with conventional co-precipitation method, advanced functional powder materials synthesized by solvothermal method exhibit fine grain size, higher crystallinity and integrity. In this work, the uniformly dispersed nickel-cobalt microsphere precursor with porous structure and fine size is prepared by solvothermal routine without any template. Subsequently, the LiNi 0.88 Co 0.12 O 2 is synthesized by high-temperature solid-state method. The feasibility of LiNi 0.88 Co 0.12 O 2 as high-performance cathode material for LIBs is explored. As a result, the as-synthesized LiNi 0.88 Co 0.12 O 2 shows excellent high-rate cyclability due to the fine size and particles integrity inherited from nickel-cobalt microsphere precursor. This study reveals that solvothermal routine is a prospective method for synthesizing new formula LiNiO 2 -based cathode material. [ABSTRACT FROM AUTHOR]

In this study, lithium terephthalate by solvothermal method with low energy consumption and simple preparation process were synthesized. To obtain the lithium terephthalate with best electrochemical properties, the effects of different organic solvents, reaction temperature and lithium source were investigated and compared. The electrochemical performance of lithium terephthalate prepared from various processing methods as lithium ion battery was furtherly analyzed and discussed. The compositions lithium terephthalate of were confirmed by XRD and FTIR, the morphologies were observed by SEM, and the electrochemical properties were analyzed by cycle charge-discharge tests. The results show that the first discharge capacity of the battery prepared by lithium hydroxide in DMF at a reaction temperature of 175 °C presented the best performance, reaching a maximum capacity of 235/74 mA⋅h/g. [ABSTRACT FROM AUTHOR]

Abstract During the charge-discharge of the LiNi 0.5 Mn 1.5 O 4 (LNMO) cathode in Li-ion batteries, Ni2+ and Mn2+ dissolve in the electrolyte to cause oxidative decomposition, which is the major cause for fast capacity fading and poor cycle performance. Reducing the direct contact area between the cathode material and the electrolyte is a direct solution to improve the cell performance. This paper focuses on a solvothermal method to coat the surface of LiNi 0.5 Mn 1.5 O 4 hollow microspheres with TiO 2 followed by TiO 2 conversion into Li 4 Ti 5 O 12 (LTO) using LiOH·H 2 O. The Li 4 Ti 5 O 12 coating layer synthesized by this method demonstrates epitaxial growth on the outer surface of LiNi 0.5 Mn 1.5 O 4. The LTO-coated LNMO cathode exhibits capacity retention of 88.1% after 100 cycles at 0.5C rate, much higher than 62.2% for the bare LNMO counterpart, at elevated temperature of 55 °C. In addition, the Li+-ion mobility for the LTO-coated LNMO electrode is increased. Highlights • Li 4 Ti 5 O 12 is coated on LiNi 0.5 Mn 1.5 O 4 hollow microspheres via a solvothermal method. • Epitaxial growth of Li 4 Ti 5 O 12 on LiNi 0.5 Mn 1.5 O 4 surface is achieved. • Li 4 Ti 5 O 12 coated LiNi 0.5 Mn 1.5 O 4 is conducive to the electrochemical performance improvement. [ABSTRACT FROM AUTHOR]

In combination of a facile and scalable solvothermal method and solid-phase reduction reactions, a novel two-dimensional black TiO2 − x nanosheet (TiO2 − x NS) with high specific surface area of 108 m2 g−1 and nearly total solar spectral absorption capability have been successfully prepared. With careful characterizations, the novel TiO2 − x NS showed enhanced electrochemical performance and visible-light photocatalytic activity than those of their white TiO2 nanosheet (TiO2 NS) precursors. The black TiO2 − x NS electrode delivered a reversible specific capacity of 160 mA h g−1 even after cycling at 0.5 C (1 C = 190 mA h g−1) for 300 times, which was significantly higher than the corresponding white TiO2 NS electrode (104 mA h g−1). Meanwhile, the TiO2 − x NS also exhibited enhanced ability of visible-light photocatalytic hydrogen production than that of the white TiO2 NS. It is expected that making white TiO2 NS into black ones is an effective way to design the photocatalysts with visible light response and the anodes with long lifetime and high rate performance in lithium ion batteries. The novel black TiO2 − x NS could find potential applications in the field of environmental management and energy storage and conversion. [ABSTRACT FROM AUTHOR]

Abstract Among various carbon materials, nitrogen doped single walled carbon nanohorns (N-SWCNHs) have a unique structure of clustered conical cages (2–5 nm in diameter and 40–50 nm in length) arranged in dahlia, bud and seed-like configurations. Each conical cage has five pentagons at their tips which act as potential reactive site with their own distinct chemistry. We exploited these reactive sites of N-SWCNHs by preferentially growing germanium nanocrystals (Ge NCs) onto their conical tips using oleylamine as a mild reducing agent. Therefore, Ge decorated N-SWCNHs (Ge@N-SWCNHs) composite was used, for the first time, as active anode material for lithium ion batteries providing high and stable capacity of 1285 mAh/g at 0.1C after 100 cycles. Our results show that preferential growth of Ge Nanocrystals (NCs) on the tips of N-SWCNHs not only allows high utilization of active material but prevents the aggregation of Ge NCs after multiple cycling. Finally, we highlight the potential role of N-SWCNHs as cheap and industrially scalable conductive host for next generation lithium ion batteries. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract Mesoporous Ti 2 Nb 10 O 29 microspheres are prepared through a solvothermal method in isopropanol-glycerol solvent followed by calcination treatment. The Ti 2 Nb 10 O 29 microspheres with diameter in the range between 1.0 and 2.0 µm are assembled from nanoparticles. The special hierarchical mesoporous structure of Ti 2 Nb 10 O 29 microspheres can reduce the Li+ ions diffusion distance and supply large interfacial area between electrolyte and electrode, endowing them with better electrochemical properties compared to Ti 2 Nb 10 O 29 nanoparticles. At different current densities of 1, 5, 10, 20 and 30 C, the first discharge capacity of mesoporous microspheres is respectively 268.9, 218.5, 205.3, 180.5, and 158.1 mA h g−1. By contrast, the corresponding values of Ti 2 Nb 10 O 29 nanoparticles are quickly reduced from 254.6, 196.3, 159.4, 127.5, to 99.0 mA h g−1. It worth noting that Ti 2 Nb 10 O 29 microspheres exhibit excellent rate capacities. Furthermore, at a current density of 10 C, the specific capacity of Ti 2 Nb 10 O 29 microspheres can be maintained at 173.5 mA h g−1 after 500 cycles, with 86.8% retention of the first discharge capacity. These results suggest that the Ti 2 Nb 10 O 29 mesoporous microspheres would be developed as potential anodic materials for high performance lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Highlights • Li 4 Ti 5 O 12 /g-C 3 N 4 composite is prepared by solvothermal method for the first time. • g-C 3 N 4 acts as a support to enhance the electronic conductivity of Li 4 Ti 5 O 12. • Li 4 Ti 5 O 12 /g-C 3 N 4 has superior cycle stability compared with pure Li 4 Ti 5 O 12. Abstract The Li 4 Ti 5 O 12 /graphitic carbon nitride (g-C 3 N 4) composite was fabricated via a solvothermal method followed by heating treatment at 700 °C for 5 h. In this method, g-C 3 N 4 acted as a support to enhance the electronic conductivity of Li 4 Ti 5 O 12. When tested as anode materials for lithium ion batteries, the as-synthesized Li 4 Ti 5 O 12 /g-C 3 N 4 composite displays a reversible capacity of as high as 150.8 mAh/g with a capacity retention of 86.8% at 0.5 C after 502 cycles. The cycling performance of the composite is enhanced, which could be attributed to the existence of g-C 3 N 4 support. [ABSTRACT FROM AUTHOR]

Abstract Well-defined porous Ti 2 Nb 10 O 29 /C microspheres have been synthesized by a one-pot solvothermal method. The as-formed Ti 2 Nb 10 O 29 /C microspheres possess good dispersity and are constructed by interconnected nanoparticles. The unique porous microstructure and modification of conduction carbon can provide large electrode-electrolyte contact areas and improve the Li+ diffusion coefficient and electronic conductivity of Ti 2 Nb 10 O 29 /C microspheres, endowing them with excellent Li+ storage properties. Ti 2 Nb 10 O 29 /C porous microspheres can deliver prominent discharge capacity of 278.7, 239.7, 236.8, 220.5 and 208.1 mAh g−1 at 1, 5, 10, 20, and 30 C, respectively. On the contrary, the discharge capacity of Ti 2 Nb 10 O 29 porous microspheres can be quickly reduced from 278.6 to 140.5 mAh g−1 (1 vs. 30C). Most importantly, Ti 2 Nb 10 O 29 /C microspheres display good rate capacity, such as 276.8 mAh g−1 at 1 C, 245.6 mAh g−1 at 10 C, 226.7 mAh g−1 at 20 C, and even 217.9 mAh g−1 at 30 C. It is deduced that the excellent rate performance is mainly caused by the pseudocapacitive effect. In addition, the discharge capacity of Ti 2 Nb 10 O 29 /C microspheres is retained to 186.7 mAh g−1 at a high current density of 10 C after 200 cycle, with 89.5% retention of the 1st cycle capacity. Graphical abstract Image 1 Highlights • Well-defined porous Ti 2 Nb 10 O 29 /C microspheres with uniform shapes are synthesized. • Ti 2 Nb 10 O 29 /C porous microspheres have extremely enhanced rate capacity. • Pseudocapacitive effect is influential to the high-rate property of Ti 2 Nb 10 O 29 /C. • Ti 2 Nb 10 O 29 /C microspheres have large discharge capacity and good cycling stability. [ABSTRACT FROM AUTHOR]

Abstract Al/Fe-doped V 6 O 13 is synthesized via a solvothermal method using V 2 O 5 , C 2 H 5 OH, Al(NO 3) 3 ·9H 2 O and Fe(NO 3) 3 ·9H 2 O as raw materials. Results of XRD show that different Al/Fe-doped amounts of V 6 O 13 are successfully synthesized. Figures of SEM reveal different morphologies of Al/Fe-doped V 6 O 13. Charge- discharge results indicate that the suitable Al/Fe-doping can improve the electrochemical performance of the material. When the mole ratio of Al/Fe is 5.33/4.95, the average width of the sample is 200 nm and the average length is 4.8 μm. This morphology can shorten the transport path of lithium ions. Meanwhile, the initial discharge specific capacity of the sample is 426.9 mAh/g, which increases by 52% compared to pure phase. The suitable Al/Fe-doping is also conducive to reducing the charge transfer resistance and increasing the diffusion rate of lithium ions. The current research results show that Al/Fe-doped V 6 O 13 has potential application value in cathode material of lithium-ion batteries. Highlights • V 6 O 13 was successfully synthesized by different Al/Fe-doping. • Suitable Al/Fe-doped V 6 O 13 has the best electrochemical performance. • Doping affects the conductivity of materials and lithium ion diffusion coefficient. • The post mortem analysis was performed to investigate the described effects during cycling. [ABSTRACT FROM AUTHOR]

The self-assembled hierarchical MnCO3/MWCNT nanoarchitectures are prepared by a facile solvothermal method and used as anode material for lithium-ion batteries. The results of SEM and TEM show that the hierarchical nanorods are made of the primary MnCO3 nanocrystals. The hierarchical nanorods MnCO3 are heterogeneously distributed among retiform MWCNTs. Those MnCO3/MWCNT nanoarchitectures are able to buffer the physical aggregation of the MnCO3 nanorods and volume expansion of MnCO3 in the charge/discharge process. The self-assembled hierarchical MnCO3/MWCNT nanocomposite delivers a reversible capacity of 704 mAh g−1 after 110 cycles at a current density of 100 mA g−1. The excellent electrochemical performance is attributed to the self-assembled hierarchical MnCO3/MWCNT nanoarchitectures and the high conductivity of MWCNTs. [ABSTRACT FROM AUTHOR]

A one-step high-temperature solvothermal approach to the synthesis of monolayer or bilayer MoS2 anchored onto reduced graphene oxide (RGO) sheet (denoted as MoS2/RGO) is described. It was found that single-layered or double-layered MoS2 were synthesized directly without an extra exfoliation step and well dispersed on the surface of crumpled RGO sheets with random orientation. The prepared MoS2/RGO composites delivered a high reversible capacity of 900 mAhg − 1 after 200 cycles at a current density of 200 mAg − 1 as well as good rate capability as anode active material for lithium ion batteries. This one-step high-temperature hydrothermal strategy provides a simple, cost-effective and eco-friendly way to the fabrication of exfoliated MoS2 layers deposited onto RGO sheets. Monolayer or bilayer MoS2 anchored onto reduced graphene oxide (RGO) sheet (denoted as MoS2/RGO) has been successfully fabricated by a one-step high-temperature solvothermal approach up to 350∘C. The as-synthesized MoS2/RGO composites delivered a high reversible capacity of 900 mAhg−1 after 200 cycles at a current density of 200 mAg−1 as well as good rate capability as anode active material for lithium ion batteries. [ABSTRACT FROM AUTHOR]

The dandelion-like V 2 O 3 /C composite was synthesized by a simple and facile template-free solvothermal method followed by a suitable thermal treatment. The dandelion-like V 2 O 3 /C composite is constructed by bicontinuous 3D hierarchical structures, which are formed by interconnected nanoparticles and interconnected pores, respectively. Moreover, the surface of interconnected nanoparticles is uniformly coated with an ultrathin carbon layer. Upon evaluation as an anode material for LIBs, the as-synthesized product shows superior electrochemical performance. Under the current density of 0.1 A g −1 , the specific discharge capacity of V 2 O 3 /C composite is 737 mA h g −1 after 100 cycles. Moreover, after 1000 cycles at a high current density of 2 A g −1 , the sample exhibits a discharge capacity of 315 mA h g −1 which is 94% of the first-cycle discharge capacity. This excellent electrochemical performance can be ascribed to its unique hierarchical structure with 3D interconnected nanopores and uniform carbon coating. [ABSTRACT FROM AUTHOR]

MnO offers remarkably high theoretical capacity based on conversion reaction for lithium-ion batteries (LIBs). However, the low electronic conductivity and large volume changes of MnO have severely limited its applications. Due to the high conductivity of carbon nanotubes (CNTs), we synthesized a three-dimensional (3D) interconnected MnO/CNTs composite by a step-by-step method to solve the above issues. The obtained 3D interconnected MnO/CNTs composite has the advantages of high capacity of MnO and the excellent conductivity of CNTs, in which CNTs were connected with each other to form an interconnected network for the embedding of nanosized MnO particles. As a consequence, the prepared 3D interconnected MnO/CNTs composite shows a high capacity of 992 mA h g −1 at 0.2 A g −1 after 150 cycles and 893 mA h g −1 at 0.5 A g −1 after 300 cycles, demonstrating the potential of promising anode material for LIBs. [ABSTRACT FROM AUTHOR]

One-pot solvothermal process is adopted to develop, 3D hierarchical Fe 3 O 4 nanoparticles supported 2D reduced graphene oxide sheets (Fe 3 O 4 /r-GO) as possible negative electrodes for lithium ion batteries. The synthesis parameters are optimized to prepare agglomeration-free Fe 3 O 4 nanostructures with uniform size and shape on r-GO. The field emission scanning electron microscopic (FESEM) image reveals that the 3D hierarchical Fe 3 O 4 nanostructures are uniformly decorated on r-GO. The physicochemical and functional properties of Fe 3 O 4 /r-GO are systematically investigated using various techniques. The fabricated Fe 3 O 4 /r-GO electrode delivers an initial discharge capacity of 1221 mAh g −1 at a current density of 100 mA g −1 and retains the specific capacity of 1560 mAh g −1 after 100 cycles. Fe 3 O 4 /r-GO significantly enhances cyclic performance, when compared with bare Fe 3 O 4 nanoparticles due to the uniform distribution of Fe 3 O 4 nanoparticles on the graphene sheet with the more number of electrochemically active sites. [ABSTRACT FROM AUTHOR]

The SnO 2 quantum dots anchored on amorphous carbon coated multiwalled carbon nanotubes (CNTs@C@SnO 2 ) and SnO 2 quantum dots embedded in amorphous carbon network (SnO 2 @C) have been designed and fabricated by a solvothermal process accompanied by a high temperature calcination treatment. Such unique structured electrodes exhibit excellent cycle stability and high rate capability. At the current density of 5 A g −1 , the capacities of 515 and 364 mAh g −1 are achieved after 300 cycles for CNTs@C@SnO 2 and SnO 2 @C, respectively. [ABSTRACT FROM AUTHOR]

The hierarchical V 2 O 5 hollow and core-shell microspheres are synthesized via solvothermal method with subsequent annealing treatment. The V 2 O 5 hollow microspheres with the mesoporous characteristics are assembled by nanosheets, which provide high specific surface area (136.33 m 2 g −1 ) and sustain good structural integrity. These advantages are conducive to obtain the excellent electrochemical performance. As the cathode materials, the V 2 O 5 hollow microspheres have no capacity fading after 100 cycles at 100 mA g −1 and deliver a capacity retention of 91.67% after 500 cycles at 500 mA g −1 , a high average capacity of 129.3 mA h g −1 can be reached even at a high current density of 5000 mA g −1 , which indicates highly reversible capacity, good cycling stability and rate capability. However, due to the agglomeration and the dissolution in the electrolyte of the active materials and the bad electrical contact between the inner and external shell, the electrochemical performance at high current densities of V 2 O 5 core-shell microspheres is disappointing. An extremely low average capacity of 11.5 mA h g −1 can be delivered at 5000 mA g −1 . Furthermore, the method of preparing core-shell microspheres provides a novel strategy for synthesizing hierarchical microspheres with void space. [ABSTRACT FROM AUTHOR]

Due to the synergistic effects of multiple transitional metals, high theoretical specific capacity and good electrical conductivity, α-MnMoO 4 exhibits superior performance and can be utilized as one prospective lithium-ion battery anode material. Herein, a new solvothermal reduction method was adopted for the synthesis and construction of α-MnMoO 4 microstructures. Both dart-like and nanosheet-based flower-like α-MnMoO 4 microstructures can be prepared by tuning the initial amount of molybdenum acetylacetone during the reaction process. The electrochemical measurements show that the dart-like α-MnMoO 4 microstructures and nanosheet-based flower-like α-MnMoO 4 microstructures deliver the stable specific capacities of 951.4 and 861.4 mA h g−1 at a current density of 0.5 A g−1 after 400 cycles. The excellent capacity, stable and sustainable cyclic performance are much superior to the reported α-MnMoO 4 particles. The improved electrochemical performance proves that α-MnMoO 4 microstructures can be served as one prospective anode of lithium-ion batteries. [Display omitted] • Binary transition metal oxide α-MnMoO 4 formed by solvothermal reduction precipitation method can be used as anodes of LIBs. • A high reversible specific capacity of 951 mA h g−1 can be achieved for dart-like α-MnMoO 4 structure at 0.5 A g−1. • The formed α-MnMoO 4 structures present great application prospect in high performance electrochemical energy storage device. [ABSTRACT FROM AUTHOR]

In present work, Sn-based composites have been successfully synthesized by the solvothermal method. The composition and content of the solvent have crucial influences on the phase composition, crystallinity and morphology of the samples. It is found that the nanoflakes assembling to the spherical SnS 2 /SnO 2 obtained in deionized water (DI w) gradually convert to nanoparticles in anhydrous ethanol (AE) solvent. The hierarchical SnS 2 /SnO 2 composites obtained in AE solvent exhibit excellent electrochemical performances. The initial discharge capacity of the anode can reach to 1420.06 mA h g −1 at 100 mA g −1 for lithium-ion batteries (LIBs), and the capacity can maintain 588.15 mA h g −1 after 50 cycles. Compared with other Sn-based anode materials, the SnS 2 /SnO 2 sample obtained in the AE solvent can still retain a stable discharge capacity of 559.16 mA h g −1 even at 800 mA g −1 . The results obtained in the work reveal the influence of the solvent on the morphology of Sn-based samples and the potential of the sphere-like SnS 2 /SnO 2 structure as LIBs anode. [ABSTRACT FROM AUTHOR]

3d transition-metal oxides, especially Fe 3 O 4 , as anode materials for the lithium-ion batteries have been attracting intensive attentions in recent years due to their high energy capacity and low toxicity. A new Fe 3 O 4 /C composite with hollow spheres in porous three-dimensional (3D) nanostructure, which was synthesized by a facile solvothermal method using FeCl 3 ·6H 2 O and porous spongy carbon as raw materials. The specific surface area and microstructures of composite were characterized by nitrogen adsorption-desorption isotherm method, FE-SEM and HR-TEM. A homogeneous distribution of hollow Fe 3 O 4 spheres (diameter ranges from 120 nm to 150 nm) in the spongy carbon (pore size > 200 nm) conductive 3D-network significantly reduced the lithium-ion diffusion length and increased the electrochemical reaction area, and further more enhanced the lithium ion battery performance, such as discharge capacity and cycle life. As an anode material for the lithium-ion battery, the title composite exhibit excellent electrochemical properties. The Fe 3 O 4 /C composite electrode achieved a relatively high reversible specific capacity of 1450.1 mA h g −1 in the first cycle at 100 mA g −1 , and excellent rate capability (69% retention at 1000 mA g −1 ) with good cycle stability (only 10% loss after 100 cycles). [ABSTRACT FROM AUTHOR]

In the work, hierarchical SnS 2 /SnO 2 composites have been successfully synthesized by a facile one-step solvothermal method. It is found that the basic nature of the solution plays a crucial role in ascertaining the phase and structures of the Sn-based products. And compared with plate-like SnS 2 nanoparticles fabricated in deionized water (DI w), the sphere-like SnS 2 /SnO 2 composites obtained in anhydrous ethanol (AE) exhibit excellent electrochemical performances as anode material for lithium-ion batteries (LIBs). The discharge capacity of SnS 2 /SnO 2 electrode retains 588.15 mA h g −1 at 100 mA g −1 after 50 cycles, and the discharge capacity of the electrode can still stably reserve 559.16 mA h g −1 even at 800 mA g −1 , demonstrating a significantly increased cycling reversibility and structural stability compared to the bare SnS 2 . The sphere-like SnS 2 /SnO 2 structure are assembled by nanoparticles, which can shorten the lithium-ions/electrons pathways, the hierarchical structure of SnS 2 /SnO 2 composites can accommodate the large volume variation. The charge/discharge performance of the SnS 2 /SnO 2 composites can also be enhanced by the synergy effects of SnS 2 and SnO 2 . [ABSTRACT FROM AUTHOR]

Porous nanosheets assembled Mn-based oxides (Mn 2 O 3 , MnCo 2 O 4 and CoMn 2 O 4 ) microspheres of diameters about 3–6 μm and pore size distribution mainly around 10 nm have been synthesized by the same facile solvothermal route without any surfactant followed by a calcination process. In virtue of the porous nanosheets constructed microspheres, the Mn-based oxides microspheres Mn 2 O 3 present specific capacities of 650 mAh/g after 100 charge and discharge cycles. Additionally among the three Mn-based oxides the representative specific capacities present an increasing trend as with the increasing percentage of Co element, the plateau of charge and discharge present a lower trend as with the increasing percentage of Mn element which is more suitable as anode materials in high output full batteries. Then the oxides with different components could be applied in different conditions such as the need for high specific capacity or high output lithium-ion batteries. Consequently the easy fabrication of microspheres and excellent electrochemical performances demonstrate Mn-based oxides’ great potential in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Porous Nb 2 O 5 microspheres have been prepared by a facile solvothermal method and subsequent heat-treatment using cheap NbCl 5 as a starting material. As anode materials for lithium-ion batteries (LIBs), porous Nb 2 O 5 microspheres show good electrochemical performance with discharge capacities of 199 mA h g −1 after 50 cycles at a current density of 100 mA g −1 and 126 mA h g −1 after 150 cycles at a current density of 500 mA g −1 , respectively. The good electrochemical performance of porous Nb 2 O 5 microspheres can be ascribed to the distinct structure of the microspheres consisted of nanoparticles with short transport route for ion and electron, large specific surface and mesoporous structure. The electrochemical testing results demonstrate that porous Nb 2 O 5 microspheres are the promising alternate as anode materials for LIBs. [ABSTRACT FROM AUTHOR]

A porous microsized composite of nano-Co 1−x S/biomass derived activated carbon (BC) was synthesized by a facile solvothermal method using rice husks as carbon source. The Co 1−x S nanoparticles with diameters of approximately 60 nm are uniformly wrapped in or attached on the biomass derived activated carbon forming a unique Co 1−x S/BC hybrid microstructure. This Co 1−x S/BC microsized composite as an anode material for lithium-ion batteries exhibits a high capacity (630 mAh g −1 at a current density of 0.1 A g −1 ) and excellently good cycle stability (about 1% capacity loss after 120 cycles) compared with bare Co 1−x S. This superb electrochemical performance is attributed to the porous structure of the composite and the homogeneous distribution of Co 1−x S nanoparticles on the biomass derived activated carbon, which could buffer the large volume change of Co 1−x S component during discharge/charge process and supply a good electronic conductivity for electrode reaction, respectively. The facile and low-cost of this microsized Co 1−x S/BC anode material may have great potential to be one alternative for traditional graphite anode. [ABSTRACT FROM AUTHOR]

Pomegranate-shaped Sn/SnO x /nanocarbon composites are fabricated via a simple one-step solvothermal method. The Sn and SnO x nanoparticles are uniformly embedded in the sheet-like nanocarbon membranes. As the anode of lithium-ion battery, the pomegranate-shaped Sn/SnO x /nanocarbon composites exhibit ultrafast-charging and long-life performance. At super high current rate of 10 C, 15 C and 20 C (the charging process is shortened to merely 6, 4 and 3 min, respectively), the reversible capacity of pomegranate-shaped Sn/SnO x /nanocarbon composites is 545, 467 and 421 mAh g −1 , respectively. After 2000 cycles, the capacity can still maintain at 192, 139 and 101 mAh g −1 at 10 C, 15 C and 20 C rate, respectively. Even after 5000 cycles at 15 C rate, the discharge capacity can still keep at 135 mAh g −1 . Such superior performance can be attributed to the unique structure, good electronic conductivity, short paths for lithium diffusion and interfacial charging mechanism. The present results indicate a new way to produce pomegranate-shaped metal/metal-oxide/nanocarbon composites with ultrafast-charging/long-life lithium-storage performance. [ABSTRACT FROM AUTHOR]

La-doped lithium-rich layered oxide material Li 1.2 Mn 0.54− x Ni 0.13 Co 0.13 La x O 2 ( x = 0.01, 0.02, 0.03) is firstly synthesized via a solvothermal method and subsequent high-temperature calcination technique. The effects of La substitution for partial Mn on the structure and electrochemical performance of materials are systematically studied by inductively coupled plasma optical emission spectroscopy (ICP-OES), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscope (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and electrochemical measurement. The results reveal that La is effectively and homogenously doped into the materials, which can expand pathway for intercalation/deintercalation of Li + ions. In addition, owing to La doping, the Li 1.2 Mn 0.52 Ni 0.13 Co 0.13 La 0.02 O 2 sample exhibits 93.2% capacity retention after 100 cycles at 1 C. More importantly, this doping can effectively restrain the decrease of average discharge voltage upon cycling, which is one of the longstanding fatal drawbacks for lithium-rich layered oxide material. Moreover, La doping can stabilize the layered framework upon long term cycling and suppress voltage fading, and thus resulting in the better cycling performance. Additionally, the rate capability is also improved by La doping due to the higher diffusion velocity of Li + ions. [ABSTRACT FROM AUTHOR]

An iron-assisted carbon coating strategy is developed to guide the formation of uniform and highly graphitized carbon layers on surfaces of the LiMn 0.8 Fe 0.2 PO 4 (LMFP) to yield cathode materials with improved electrochemical performance. A small amount of iron oxalate is added as a catalyst precursor, which decomposes into ferrous oxide (FeO) at high temperature. During the calcination process, FeO is reduced to iron (Fe) that helps to transform amorphous carbon into graphitized carbon which is deposited uniformly and tightly on surfaces of LMFP materials. The impact of Fe atoms on the formation of highly graphitized carbon layers as well as the electrochemical performances of the resulting LMFP/Fe/Carbon (LMFP/Fe/C), is evaluated. Compared to LMFP/C without iron oxalate, LMFP/Fe/C exhibited substantial discharge capacity and better rate and cycling performances. Discharge capacities of 152.3, 141.9, 132.1, 105.6 and 76.0 mAh g −1 are recorded at 0.2, 0.5, 1, 5 and 10 C, respectively. The retention capacity remained 78.6% at 10 C after 60 cycles. Furthermore, the conductivity and the lithium ion diffusion processes of LMFP/Fe/C are improved. [ABSTRACT FROM AUTHOR]

A one-pot and template-free solvothermal method was developed to synthesize the hierarchical WO 3 hollow microspheres with porous shells. The porous shell of as-synthesize WO 3 hollow microspheres are constructed from primary nanoplates clusters of 50 nm. The as-synthesize WO 3 hollow microspheres are not monodisperse, and most of hollow microspheres are interconnected by sharing one wall. Importantly, the as-synthesize WO 3 hollow microspheres exhibit excellent electrochemical performance. At current density of 100 mA g −1 , they can deliver a specific capacity of 1700 mA h g −1 in the first discharge and retain a specific capacity of 700 mA h g −1 after 100 cycles. Meanwhile, even at a high current density of 1600 mA g −1 , they also exhibit a specific capacity of 213 mA h g −1 after 500 cycles. This superior electrochemical performance of the as-synthesized WO 3 hollow microspheres could be ascribed to its unique hierarchical architecture. [ABSTRACT FROM AUTHOR]

Rhombohedron-like LiFePO 4 platelets with preferentially exposed (010) plane are synthesized via solvothermal reaction using 30 vol.% Polyethylene glycol (PEG) solution as solvent. The mechanism of the PEG-induced crystal growth of the LiFePO 4 platelets under solvothermal circumstance is revealed. The crystal structure, micro morphology and electrochemical performance of the prepared LiFePO 4 platelets are studied by means of X-Ray diffraction (XRD), scanning electron microscope (SEM), high-resolution transmission electron microscopy (HRTEM), electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge test. Due to the preferential growth of (010) lattice plane facilitating diffusion of Li-ions, the LiFePO 4 material shows excellent electrochemical performance. The as-obtained products deliver initial discharge capacities of 166.8 mAh g − 1 with an initial Coulombic efficiency of 99.4% at 0.1C, discharge capacities of 144.7 mAh g − 1 at 1C and discharge capacities of 116.5 mAh g − 1 at 5C. Moreover, the discharge capacities after 262 cycles at 1C are 142.4 mAh g − 1 (capacity retention is 98.4%). This solvothermal reaction approach is a promising strategy for the commercialization of LiFePO 4 cathode in lithium ion batteries. [ABSTRACT FROM AUTHOR]

Well-dispersed LiFePO 4 nanorods in diameter of ca. 70 nm and length of 90–150 nm are prepared via a solvothermal method in the water-ethylene glycol (1:15, v/v) mixture. The microstructure and crystal orientation are characterized by high-resolution transmission electron microscopy and X-ray diffraction. The effects of carbon content on the electrochemical performances of LiFePO 4 nanorods are investigated. Benefiting from the oriented nanorods and the optimized conductive carbon network, the LiFePO 4 /C composites exhibit remarkable cycling stability and high rate capacity. The LiFePO 4 /C including 9 wt% carbon delivers a large discharge capacity of 120 mAh g −1 at 10 C rate with the capacity retention of 83% after 2000 cycles. Furthermore, the capacity retention of LiFePO 4 /C with 6 wt% carbon is up to 96% after 150 cycles at elevated temperature (50 °C) at 1 C rate. [ABSTRACT FROM AUTHOR]

Anatase TiO 2 aligned arrays supported on carbon cloth (termed as ATAC) composites are successfully prepared as a high-performance anode material for Li-ion batteries. The obtained ATAC displays enhanced cycling performance and rate capability, which shows an initial discharge capacity of 390 mA h g −1 and a remaining capacity of 188 mA h g −1 for the ATAC after 500 cycles. The enhanced electrochemical performance of the ATAC is related to the synergistic effect between ATO arrays and carbon fibers. [ABSTRACT FROM AUTHOR]