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Owing to its abundance and high theoretical capacity, phosphorus has attracted intense research interest as anode material for lithium-ion batteries. However, the adaption of phosphorus for batteries is still limited by its poor electrochemical performance, which is associated with its poor electronic conductivity and large volume change during charging and discharging. We herein report a facile and cost-effective method, which is based on high-energy mechanical milling, for the synthesis of phosphorus nanoparticles within carbon matrix as high-performance anode materials. Red phosphorus was readily transformed into orthorhombic black phosphorus at ambient temperature and pressure, forming phosphorus nanocrystals homogenously dispersed in carbon matrix. Such composites provide superior electrochemical performance, exhibiting reversible capacity of 1000 mA h g−1 after 300 cycles. Full cells based on such phosphorus-carbon composites against LiNi1/3Co1/3Mn1/3O2 cathode offer a capacity retention of 92% after 200 cycles at 0.5 C.

Conventional liquid electrolytes for lithium batteries usually suffer from irreversible decomposition and safety concerns. Solid state electrolytes (SSEs) have been considered as the key for advanced lithium batteries with improved energy density and safety, whereas challenges remain for polymer and inorganic SSEs. Recently, hybrid solid-state electrolytes (HSSEs) that integrate the merits of different electrolyte systems have been under intensive study. Herein, we summarize the recent progress of HSSEs with different compositions and structures. The design principle of each type of HSSEs are discussed, as well as their ionic conducting mechanism, electrochemical performance and effects of compositional/structural control. Finally, challenges and perspectives are provided for the future development of HSSEs and solid-state lithium batteries.

Lithium ion capacitors (LICs) hold potentials to bridge the gap between lithium ion batteries and supercapacitors ; however, the imbalance of electrochemical kinetic and stability between Li + storage anode and capacitive cathode has been the key bottleneck. Herein, we report a high-rate and ultrastable anode for this issue, consisting of boron-doped nanoporous carbon spheres which are synthesized by a continuous spraying-assisted co-assembly process. Experimental and computational investigations as well as the comparison with a nitrogen-rich carbon indicate that boron species enhances ion-surface interactions, electron/ion conductivity and carbon framework cycling firmness, leading to dramatically improved rate and cycling performances, which outperform the extensively explored nitrogen doped carbons and most reported high-rate anode materials . By pairing a coal-derived microporous graphene cathode, we constructed a full-carbon LIC device exhibiting high energy and power densities (207 Wh kg −1 at 511 W kg−1 and still 136 Wh kg−1 at 17.06 kW kg−1), as well as an unprecedented cycling stability with no capacity decay after 15,000 cycles at 2 A g−1. This work not only offers a fundamental basis to understand the enhanced anode performance by doping boron into carbon framework but also provides an effective strategy to circumvent the kinetic and stability discrepancies between anode and cathode for high-performance LICs.

Construction of metal–organic frameworks with sophisticated nanostructures remains a considerable challenge. Herein, we report the rational design and synthesis of ZIF-67 nanoscaffolds and defected nanocubes co-mediated by dopamine and polyoxometalate. The formation of these sophisticated ZIF-67 nanostructures is achieved through the protection of dopamine and etching of polyoxometalate. As a demonstration, we have converted the ZIF-67 nanoscaffolds incorporated with molybdenum into carbon-coated cobalt–molybdenum mixed selenides (denoted as CoMoSe@C nanoscaffolds) with little alteration in the structure by reacting the ZIF-67 nanoscaffolds with selenium powder at high temperature. Benefiting from their unique structural merits, the CoMoSe@C nanoscaffolds exhibit enhanced lithium storage properties in terms of good cycling performance and superior rate capability.

Silicon holds great promise as an anode material for lithium-ion batteries with higher energy density; its implication, however, is limited by rapid capacity fading. A catalytic growth of graphene cages on composite particles of magnesium oxide and silicon, which are made by magnesiothermic reduction reaction of silica particles, is reported herein. Catalyzed by the magnesium oxide, graphene cages can be conformally grown onto the composite particles, leading to the formation of hollow graphene-encapsulated Si particles. Such materials exhibit excellent lithium storage properties in terms of high specific capacity, remarkable rate capability (890 mAh g-1 at 5 A g-1 ), and good cycling retention over 200 cycles with consistently high coulombic efficiency at a current density of 1 A g-1 . A full battery test using LiCoO2 as the cathode demonstrates a high energy density of 329 Wh kg-1 .

Hollow structures of rutile TiO2 , and especially with non-spherical shape, have rarely been reported. Herein, high-quality rutile TiO2 submicroboxes have been synthesized by a facile templating method using Fe2 O3 submicrocubes as removable templates. Compared to other rutile TiO2 nanomaterials, the as-prepared rutile TiO2 submicroboxes manifest superior lithium storage properties in terms of high specific capacity, long-term cycling stability, and excellent rate capability.

Solid-state electrolytes are the key to the development of lithium-based batteries with dramatically improved energy density and safety. Inspired by ionic channels in biological systems, a novel class of pseudo solid-state electrolytes with biomimetic ionic channels is reported herein. This is achieved by complexing the anions of an electrolyte to the open metal sites of metal-organic frameworks (MOFs), which transforms the MOF scaffolds into ionic-channel analogs with lithium-ion conduction and low activation energy. This work suggests the emergence of a new class of pseudo solid-state lithium-ion conducting electrolytes.

Lithium–sulfur batteries, notable for high theoretical energy density, environmental benignity, and low cost, hold great potential for next-generation energy storage. Polysulfides, the intermediates generated during cycling, may shuttle between electrodes, compromising the energy density and cycling life. We report herein a class of regenerative polysulfide-scavenging layers (RSL), which effectively immobilize and regenerate polysulfides, especially for electrodes with high sulfur loadings (e.g., 6 mg cm–2). The resulting cells exhibit high gravimetric energy density of 365 Wh kg–1, initial areal capacity of 7.94 mAh cm–2, low self-discharge rate of 2.45% after resting for 3 days, and dramatically prolonged cycling life. Such blocking effects have been thoroughly investigated and correlated with the work functions of the oxides as well as their bond energies with polysulfides. This work offers not only a class of RSL to mitigate shuttling effect but also a quantified design framework for advanced lithium–...

Despite the great advantages of hollow structures as electrodes for lithium-ion batteries, one apparent common drawback which is often criticized is their compromised volumetric energy density due to the introduced hollow interior. Here, we design and synthesize bowl-like SnO2 @carbon hollow particles to reduce the excessive hollow interior space while retaining the general advantages of hollow structures. As a result, the tap density can be increased about 30 %. The as-prepared bowl-like SnO2 @carbon hollow particles with conformal carbon support exhibit excellent lithium storage properties in terms of high capacity, stable cyclability and excellent rate capability.

Hierarchical MoS2 microboxes constructed by ultrathin nanosheets are synthesized by a facile template-assisted strategy. The first step involves the L-cysteine assisted uniform growth of hierarchical MoS2 nanosheets on MnCO3 microcube templates which are at the same time converted to MnS. Hierarchical MoS2 microboxes can be obtained by selectively dissolving MnS through acid washing. When evaluated as an anode material for lithium-ion batteries, the hierarchical MoS2 microboxes manifest high specific capacity and excellent cycling performance. The hierarchical MoS2 microboxes also show enhanced electrocatalytic activity for electrochemical hydrogen evolution from water.

A facile two-step strategy involving a polyol method and subsequent thermal annealing treatment is successfully developed for the general synthesis of metal oxide/carbon coaxial nanocables. Benefitting from the strong coupling effect, these hybrid nanocables exhibit remarkable lithium storage properties with high capacity, long cycle life and excellent rate capability.

In this work, rattle-type ball-in-ball V2O5 hollow microspheres are controllably synthesized with the assistance of carbon colloidal spheres as hard templates. Carbon spheres@vanadium-precursor (CS@V) core–shell composite microspheres are first prepared through a one-step solvothermal method. The composition of solvent for the solvothermal synthesis has great influence on the morphology and structure of the vanadium-precursor shells. V2O5 hollow microspheres with various shell architectures can be obtained after removing the carbon microspheres by calcination in air. Moreover, the interior hollow shell can be tailored by varying the temperature ramping rate and calcination temperature. The rattle-type V2O5 hollow microspheres are evaluated as a cathode material for lithium-ion batteries, which manifest high specific discharge capacity, good cycling stability and rate capability.

Owing to their unique structural features, hollow micro-/ nanostructures have aroused intense research interest in a wide range of areas such as energy storage, catalysis, chemical sensors, and biomedical applications. [ 1–10 ] The templating method is considered the most representative and straightforward route to fabricate hollow structures with well-defi ned morphologies and high uniformity. [ 11 ] This versatile method generally involves the growth of a shell of designed materials against various templates (e.g., monodisperse colloidal polymer/silica spheres) to form a core–shell structure, and the subsequent removal of the interior materials, which conceptually facilitates the manipulation of the size, shape, and local chemical environment of the resultant hollow structures. [ 2 , 12 , 13 ] Nevertheless, practically, templating methods face quite a few challenges, such as the diffi culty to achieve uniform coating due to compatibility issues between the template and desired shell materials. [ 14 ] Moreover, removal of the interior templates, which is usually through tedious etching/calcination treatments and likely causes collapse and deformation of the exterior shell, holds another key to obtain well-defi ned hollow structures. Very recently, a few works have reported the syntheses of hollow structures by modifi ed templating strategies, which simultaneously realize the functionalization of the exterior shell and the elimination of the internal template. Zhao and coworkers reported the fabrication of Fe 3 O 4 @titanate yolk–shell microspheres from TiO 2 @SiO 2 @ Fe 3 O 4 core–shell structures. [ 15 ] The outmost TiO 2 shell was converted into titanate nanosheets during the removal of the SiO 2 layer through a facile hydrothermal approach in a NaOH solution. Our group has previously reported the synthesis of NiS hollow spheres from SiO 2 @nickel silicate core–shell structures by a one-step hydrothermal reaction in a Na 2 S solution, during which the sulfi dation of nickel silicate and dissolution of silica take place at the same time. [ 16 ] However, such modifi ed templating strategies have not been widely practiced yet. Spinel Li 4 Ti 5 O 12 has been extensively investigated as one of the most promising anode materials for high-rate lithium-ion batteries (LIBs) because of the zero volume change during lithiation and improved safety in operation. [ 17–19 ] Typically, Li 4 Ti 5 O 12 can accommodate three Li + ions during the intercalation process to form Li 7 Ti 5 O 12 , resulting in a theoretical specifi c capacity of 175 mA h g − 1 . [ 18 , 20 ] It has been demonstrated that Li 4 Ti 5 O 12 anodes with high performance can be achieved by proper nanostructuring. [ 19 , 21–25 ] Inspired by the successful use of many

Hierarchical three-dimensional (3D) vanadium oxide microstructures, including urchin-like microflowers, nanohorn-structured microspheres, nanosheet-assembled microflowers, and nanosheets bundles, are successfully synthesized by a versatile template-free solvothermal method. It is found that the concentration of the precursor (VOC(2)O(4)) solution has a significant effect on the morphologies of the products. As an example, the time-dependent phase and morphology evolution for the urchin-like vanadium oxide microflowers has been investigated in detail. Urchin-like VO(2) microflowers can be self-assembled within 2 h without using any surfactants. After calcination, the VO(2) microflowers can be easily transformed to urchin-like V(2)O(5) microstructures. The as-obtained V(2)O(5) microflowers are highly porous with a specific surface area of 33.64 m(2) g(-1). When evaluated as a cathode material for lithium-ion batteries, the V(2)O(5) sample delivers very high specific discharge capacity of 267 mA h g(-1) at a current density of 300 mA g(-1). Further, it also exhibits improved cycling stability. The excellent electrochemical performance is attributed to multiple advantageous structural features, including the nanosized building blocks, high porosity, and the 3D hierarchical microstructures.

In this work, we report a facile approach to mass produce carbon-coated MoS2 (C-MoS2) nanorods with high uniformity. The C-MoS2 nanorods are prepared using MoO3 nanorods as the precursor via a sulfidation and subsequent chemical vapor deposition (CVD) of an amorphous carbon layer. When evaluated as an anode material for lithium-ion batteries, the C-MoS2 nanorods exhibit improved reversibility and cycling performance compared with the bare MoS2 nanorods. A high capacity of 621 mA h g−1 can be retained after 80 cycles at a current density of 200 mA g−1. The rate capability of the C-MoS2 nanorods is also improved. The carbon layer is believed to better retain the structure upon prolonged cycling and to improve the conductivity of the material. This simple strategy using gas-phase sulfidation and CVD carbon coating could also be applied to prepare other nanostructured carbon-coated metal sulfides. Keywords: MoS2, Nanorods, Carbon coating, Lithium-ion batteries, Anode

Layered protonated titanates (LPTs), a class of interesting inorganic layered materials, have been widely studied because of their many unique properties and their use as precursors to many important TiO(2)-based functional materials. In this work, we have developed a facile solvothermal method to synthesize hierarchical spheres (HSs) assembled from ultrathin LPT nanosheets. These LPT hierarchical spheres possess a porous structure with a large specific surface area and high stability. Importantly, the size and morphology of the LPT hierarchical spheres are easily tunable by varying the synthesis conditions. These LPT HSs can be easily converted to anatase TiO(2) HSs without significant structural alteration. Depending on the calcination atmosphere of air or N(2), pure anatase TiO(2) HSs or carbon-supported TiO(2) HSs, respectively, can be obtained. Remarkably, both types of TiO(2) HSs manifest excellent cyclability and rate capability when evaluated as anode materials for high-power lithium-ion batteries.

In this work, we have developed a facile hydrothermal method to synthesize various 3D hierarchical structures assembled from 2D SnO2 nanosheets. The samples were thoroughly characterized by FESEM/TEM/XRD/BET techniques. Through in-depth investigation of experimental conditions, it is discovered that the oxidation process is crucial for the formation of the nanosheet structure. The electrochemical properties of the sample were subsequently studied by cyclic voltammetry and charge–discharge cycling. When compared to SnO2 nanoparticles from a commercial source, the result shows that the as-prepared hierarchical SnO2 nanostructure exhibits much better lithium storage properties with higher reversible capacities and improved cyclic capacity retention for extended cycling.

A facile one-pot hydrothermal method has been developed for the preparation of carbon-coated MoO(2) nanocrystals. The annealed MoO(2)-C nanocomposite consists of interconnected MoO(2)@C nanocrystals. When evaluated for lithium storage capabilities, these MoO(2)@C nanocrystals exhibit high specific capacities (~640 mA h g(-1) at 200 mA g(-1) and ~575 mA h g(-1) at 400 mA g(-1)) and excellent cycling stability. In view of the excellent lithium storage properties and the ease in large-scale preparation, the as-synthesized MoO(2)-C nanocomposite might be used as promising anode materials for high-performance lithium-ion batteries.

Titanium niobium oxide (TiNb2O7) has been recognized as a promising anode material for lithium-ion batteries (LIBs) in view of its potential to operate at high rates with improved safety and high theoretical capacity of 387 mAh g−1. However, it suffers from poor Li+ ion diffusivity and low electronic conductivity originated from its wide band gap energy (Eg > 2 eV). Here, porous TiNb2O7 microspheres (PTNO MSs) are prepared via a facile solvothermal reaction. PTNO MSs have a particle size of ≈1.2 μm and controllable pore sizes in the range of 5–35 nm. Ammonia gas nitridation treatment is conducted on PTNO MSs to introduce conducting Ti1−xNbxN layer on the surface and form nitridated PTNO (NPTNO) MSs. The porous structure and conducting Ti1−xNbxN layer enhance the transport kinetics associated with Li+ ions and electrons, which leads to significant improvement in electrochemical performance. As a result, the NPTNO electrode shows a high discharge capacity of ≈265 mAh g−1, remarkable rate capability (≈143 mAh g−1 at 100 C) and durable long-term cyclability (≈91% capacity retention over 1000 cycles at 5 C). These results demonstrate the great potential of TiNb2O7 as a practical high-rate anode material for LIBs.

Hierarchical Fe3 O4 hollow spheres constructed by nanosheets are obtained from solvothermally synthesized Fe-glycerate hollow spheres. With the unique structural features, these hierarchical Fe3 O4 hollow spheres exhibit excellent electrochemical lithium-storage performance.

While the synthesis of TiO2 hollow structures is well-established, in most cases it is particularly difficult to control the crystallization of TiO2 in solution or by calcination. As a result, TiO2 hollow structures do not really exhibit enhanced lithium storage properties. Herein, we report a simple and cost-effective template-assisted method to synthesize anatase TiO2 hollow spheres composed of highly crystalline nanocrystals, in which carbonaceous (C) spheres are chosen as the removable template. The release of gaseous species from the combustion of C spheres may inhibit the growth of TiO2 crystallites so that instead small TiO2 nanocrystals are generated. The small size and high crystallinity of primary TiO2 nanoparticles and the high structural integrity of the hollow spheres gives rise to significant improvements in the cycling stability and rate performance of the TiO2 hollow spheres.

Carbon-coated NiCo2 O4 @SnO2 core-shell hetero-nanostructures are synthesized by a facile hydrothermal process and subsequent carbon nano-coating. When evaluated as anode materials for lithium-ion batteries, the 3D hetero-nanostructures exhibit enhanced lithium storage properties due to advantageous structural features.

Novel nano-heterostructures composed of Fe2O3 hollow nanorods on both the outer and inner surface of the aligned TiO2 nanotube arrays (TNAs) have been fabricated by growing FeOOH nanospindles onto the TNAs, and then followed by thermal transformation in air. Owing to their structural advantages, such a hierarchical architecture exhibits superior electrochemical performance with a remarkable areal capacity of over 600 μA h cm−2 at a current density of 100 μA cm−2 for 50 cycles (∼680 μA h cm−2 at 100 μA cm−2). This hierarchal structure might be easily integrated as a binder-free electrode for microscale lithium-ion batteries considering the improved performance and the simple synthesis.

Nanosheet-assembled hierarchical V(2)O(5) hollow microspheres are successfully obtained from V-glycolate precursor hollow microspheres, which in turn are synthesized by a simple template-free solvothermal method. The structural evolution of the V-glycolate hollow microspheres has been studied and explained by the inside-out Ostwald-ripening mechanism. The surface morphologies of the hollow microspheres can be controlled by varying the mixture solution and the solvothermal reaction time. After calcination in air, hierarchical V(2)O(5) hollow microspheres with a high surface area of 70 m(2) g(-1) can be obtained and the structure is well preserved. When evaluated as cathode materials for lithium-ion batteries, the as-prepared hierarchical V(2)O(5) hollow spheres deliver a specific discharge capacity of 144 mA h g(-1) at a current density of 100 mA g(-1), which is very close to the theoretical capacity (147 mA h g(-1)) for one Li(+) insertion per V(2)O(5) . In addition, excellent rate capability and cycling stability are observed, suggesting their promising use in lithium-ion batteries.

Hierarchical tubular structures constructed by ultrathin carbon-coated SnO(2) nanoplates are rationally designed and synthesized. This interesting structure simultaneously integrates the structural and compositional design rationales for high-energy anode materials based on low-dimensional ultrathin nanoplates, a hollow tubular structure, and a carbon nanocoating. When evaluated as an anode material for lithium-ion batteries, the as-synthesized SnO(2)-carbon hybrid structure manifests high specific capacity and excellent cycling stability.

Uniform and stable micro-sized SnO(2) hollow spheres are prepared by templating against polystyrene microspheres. After being coated with a thin layer of amorphous carbon, the as-obtained SnO(2)@carbon hollow microspheres are shown to exhibit improved lithium storage properties, delivering a reversible capacity of 570 mA h g(-1) after 50 cycles at a high current density of 400 mA g(-1).

Hierarchically structured nanocables with TiO2 nanosheets anchored on carbon nanotubes are prepared from carbon nanotubes and Ti(O-Bu)4 dispersed in a mixture of DMF and iPrOH (autoclave, 180 °C, 20 h) followed by calcination in N2 at 500 °C for 2 h.

Novel ZnMn(2)O(4) ball-in-ball hollow microspheres are fabricated by a facile two-step method involving the solution synthesis of ZnMn-glycolate hollow microspheres and subsequent thermal annealing in air. When evaluated as an anode material for lithium-ion batteries, these ZnMn(2)O(4) ball-in-ball hollow microspheres show significantly enhanced electrochemical performance with high capacity, excellent cycling stability and good rate capability.

The search for new electrode materials for lithium-ion batteries (LIBs) has been an important way to satisfy the ever-growing demands for better performance with higher energy/power densities, improved safety and longer cycle life. Nanostructured metal oxides exhibit good electrochemical properties, and they are regarded as promising anode materials for high-performance LIBs. In this feature article, we will focus on three different categories of metal oxides with distinct lithium storage mechanisms: tin dioxide (SnO(2)), which utilizes alloying/dealloying processes to reversibly store/release lithium ions during charge/discharge; titanium dioxide (TiO(2)), where lithium ions are inserted/deinserted into/out of the TiO(2) crystal framework; and transition metal oxides including iron oxide and cobalt oxide, which react with lithium ions via an unusual conversion reaction. For all three systems, we will emphasize that creating nanomaterials with unique structures could effectively improve the lithium storage properties of these metal oxides. We will also highlight that the lithium storage capability can be further enhanced through designing advanced nanocomposite materials containing metal oxides and other carbonaceous supports. By providing such a rather systematic survey, we aim to stress the importance of proper nanostructuring and advanced compositing that would result in improved physicochemical properties of metal oxides, thus making them promising negative electrodes for next-generation LIBs.

Kept cubic: MnS microboxes, which act as an anode material for lithium ion batteries, are synthesized by a simple H(2)S gas sulfidation approach (TEM images show porous and hollow microcubes and a microbox). The formation of the single crystals is aided by the intrinsic cubic crystal structure and the nearly cubic shape of the MnCO(3) precursor.

Obey the hierarchy! Hierarchically structured nanocables with TiO2 nanosheets (TiO2-NSs) anchored on carbon nanotubes (CNTs) have been synthesized by growing layered hydrogen titanate (LHT) nanosheets on carbon nanotubes, followed by thermal transformation (see figure). This unique structure possesses the advantages of shortened Li+ ion diffusion length and enhanced electronic conductivity, as well as high structural stability.

α-Fe(2)O(3) hollow spheres with sheet-like subunits are synthesized by a facile quasiemulsion-templated method. Glycerol is dispersed in water to form oil-in-water quasiemulsion microdroplets, which serve as soft templates for the deposition of the α-Fe(2)O(3) shell. When tested as anode materials for lithium-ion batteries, these α-Fe(2)O(3) hollow spheres manifest greatly enhanced Li storage properties.

In this work, we demonstrate a unique organic solvent system to synthesize asymmetric anatase TiO(2) nanocrystals with a bipyramidal structure, where the upper pyramid is bound by (201) facets, and the lower pyramid is bound by (401) surfaces. Due to the high surface energy of these (401) high-index facets, the nanocrystals tend to assemble on these facets to minimize the free energy, leading to the formation of a dandelion-like hierarchical structure.

Hybrid nanostructures based on graphene and transition metal oxides hold great promise as high-performance electrode materials for next-generation lithium-ion batteries. In this work, the rational design and fabrication of NiCo2O4 nanosheets supported on reduced graphene oxide (denoted as rGO/NiCo2O4) is presented as a novel anode material for highly efficient and reversible lithium storage. A solution method is applied to grow Ni-Co precursor nanosheets on rGO, in which the addition of trisodium citrate is found crucial to guide the formation of uniform Ni-Co precursor nanosheets. Subsequent thermal treatment results in formation of crystalline NiCo2O4 nanosheets on rGO without damaging the morphology. The interconnected NiCo2O4 nanosheets form hierarchically porous films on both sides of rGO. Such a hybrid nanostructure would effectively promote the charge transport and withstand volume variation upon prolonged charge/discharge cycling. As a result, the rGO/NiCo2O4 nanocomposite demonstrates high reversible capacities of 954.3 and 656.5 mAh g–1 over 50 cycles at current densities of 200 and 500 mA g–1 respectively, and remarkable capacity retention at increased current densities. Published version

Porous SnO2 microboxes with a high uniformity and well-defined non-spherical hollow structure are prepared via a selective leaching strategy using ZnSn(OH)6 microboxes as the starting material. The selective removal of Zn(II) species by an acid-washing process produces pure SnO2 microboxes with a porous shell. After further wrapping with an elastic carbon matrix, the resultant SnO2@C microboxes exhibit excellent electrochemical performance as an anode material for lithium-ion batteries.

Porous Fe2O3 nanocubes composed of fine Fe2O3 nanoparticles have been facilely synthesized by simultaneous oxidative decomposition of Prussian blue (PB) nanocubes at high temperature. When evaluated as an anode material for lithium-ion batteries, the as-obtained porous Fe2O3 nanocubes manifest high specific capacity (∼800 mA h g−1 at 200 mA g−1) and excellent cycling performance.

A facile hydrothermal method has been developed to synthesize phase-pure SnO2 nanosheets with controlled morphology. The electrochemical measurements show that the as-prepared sample exhibits improved lithium storage properties as an anode material for lithium-ion batteries.

In this work, we demonstrate a unique organic solvent system to synthesize asymmetric anatase TiO2 nanocrystals with a bipyramidal structure, where the upper pyramid is bound by (201) facets, and the lower pyramid is bound by (401) surfaces. Due to the high surface energy of these (401) high-index facets, the nanocrystals tend to assemble on these facets to minimize the free energy, leading to the formation of a dandelion-like hierarchical structure.