A stirring hydrothermal process that enables the formation of elongated bending TiO2 -based nanotubes is presented. By making use of its bending nature, the elongated TiO2 (B) nanotubular crosslinked-network anode electrode can cycle over 10 000 times in half cells while retaining a relatively high capacity (114 mA h g(-1)) at an ultra-high rate of 25 C (8.4 A g(-1)).

The state-of-the-art development of fabrication strategies of multi-dimensional titanate and titania nanostructures is reviewed first. This is followed by an overview of their potential applications in environmental, energy, and biomedical sectors.

application. [ 1,2 ] However, bulk or microsize red P materials suffer from dramatic capacity reduction and poor cyclability with continued usage [ 1h ] due to their electronic insulation (≈10 −14 S cm −1 ) [ 1f ] and irreversible reaction related to the pulverization of particles, [ 1c , 3 ] which is caused by drastic volume change (>300%) [ 1h ] during cycling process. In light of this, black P is an alternative electrode material for high-performance LIB application due to its high electrical conductivity (≈10 2 S cm −1 ) [ 1h , 4 ] and fast kinetics during the Li + intercalating process. [ 4a,c ] Nevertheless, the traditional high-pressure method (>1 GPa, Scheme 1 a) through a pressure-induced structure-change mechanism is extremely diffi cult as it relies on specifi cally designed apparatus under controlled temperature (≥200 °C). [ 4c , 5 ] Recently, a facile mineralizer-assisted gas-phase transformation method was developed to produce large-size bulk black P. [ 6 ] However, the resultant particles by the above approaches are more than tens of micrometers in size, [ 5a , 6 ] which renders them unsuitable for high-rate LIB application. Therefore, material nanostructuring and engineering of the red/black P toward the improvement of electrical/ionic conductivity and the alleviation of volume expansion is desired for high-rate LIBs. [ 7 ] To this end, conductive confi gurations of nanostructured phosphorus materials (amorphous or red P, P-C composites, and metal phosphide, Scheme 1 a) [ 1d,e , 2e , 8 ] with buffering of volume change are widely explored through mechanical approaches (e.g., hand-grinding, mechanical milling, etc., as shown in Table S1, Supporting Information). [ 1f , 2a , 3,9 ] Furthermore, an emerging high energy mechanical milling by generating the suffi cient pressure (≈6 GPa) and temperature, [ 1c ] (Scheme 1 a), could even produce the most thermodynamically stable black P or composites with the particles size down to subhundred nanometer, which showed improved LIB performance. [ 1c,h ] Impressively, these nanostructured phosphorus or its composites [ 1d,e , 8 ] could realize high capacity (>1000 mAh g −1 ) as well as long-cycling life (>100 cycles) for LIBs. However, these top-down mechanical approaches remain diffi cult with respect to obtaining largescale uniform distribution of phosphorus nanostructures, as Phosphorus-based materials are promising for high-performance lithium-ion battery (LIB) applications due to their high theoretical specifi c capacity. Currently, the existing physical methods render great diffi culty toward rational engineering on the nanostructural phosphorus or its composites, thus limiting its high-rate LIB applications. For the fi rst time, a sublimation-induced synthesis of phosphorus-based composite nanosheets by a chemistry-based solvothermal reaction is reported. Its formation mechanism involves solidvapor-solid transformation driven by continuous vaporization-condensation process, as well as subsequent bottom-up assembly growth. The proof-o...

Spinel LiNi Mn O (LNMO) is the most promising cathode material for achieving high energy density lithium-ion batteries attributed to its high operating voltage (≈4.75 V). However, at such high voltage, the commonly used battery electrolyte is suffered from severe oxidation, forming unstable solid-electrolyte interphase (SEI) layers. This would induce capacity fading, self-discharge, as well as inferior rate capabilities for the electrode during cycling. This work first time discovers that the electrolyte oxidation is effectively negated by introducing an electrochemically stable silk sericin protein, which is capable to stabilize the SEI layer and suppress the self-discharge behavior for LNMO. In addition, robust mechanical support of sericin coating maintains the structural integrity during the fast charging/discharging process. Benefited from these merits, the sericin-based LNMO electrode possesses a much lower Li-ion diffusion energy barrier (26.1 kJ mol ) for than that of polyvinylidene fluoride-based LNMO electrode (37.5 kJ mol ), delivering a remarkable high-rate performance. This work heralds a new paradigm for manipulating interfacial chemistry of electrode to solve the key obstacle for LNMO commercialization, opening a powerful avenue for unlocking the current challenges for a wide family of high operating voltage cathode materials (>4.5 V) toward practical applications.

Thermal self-protected intelligent electrochemical storage devices are fabricated using a reversible sol-gel transition of the electrolyte, which can decrease the specific capacitance and increase and enable temperature-dependent charging and discharging rates in the device. This work represents proof of a simple and useful concept, which shows tremendous promise for the safe and controlled power delivery in electrochemical devices.

Solution-processable inks based on lithium titanate with a conductive network architecture, toward high-rate lithium-ion batteries (LIBs) with a customized configuration are developed. The inks, with tunable viscosity, are compatible for on-demand coating techniques. The lithium titanate electrode derived from these inks exhibits excellent high-rate capacity (≈124 mA h g(-1) at 90 C, 15.7 A g(-1) ) after 1000 cycles.

The fundamental understanding of the relationship between the nanostructure of an electrode and its electrochemical performance is crucial for achieving high-performance lithium-ion batteries (LIBs). In this work, the relationship between the nanotubular aspect ratio and electrochemical performance of LIBs is elucidated for the first time. The stirring hydrothermal method was used to control the aspect ratio of viscous titanate nanotubes, which were used to fabricate additive-free TiO2 -based electrode materials. We found that the battery performance at high charging/discharging rates is dramatically boosted when the aspect ratio is increased, due to the optimization of electronic/ionic transport properties within the electrode materials. The proof-of-concept LIBs comprising nanotubes with an aspect ratio of 265 can retain more than 86 % of their initial capacity over 6000 cycles at a high rate of 30 C. Such devices with supercapacitor-like rate performance and battery-like capacity herald a new paradigm for energy storage systems.

For the purpose of efficiently utilizing the renewable solar energy, it is of vital importance to understand the key factors that contribute to the performance merits for photocatalysis applications. In this work, we find that anatase titania nanostructures with high efficiency in photoelectrochemical cell (PEC) do not necessarily retain the same good performance when used in direct heterogeneous reaction (DHR). Investigation is carried out to elucidate how the electronic properties of the different nanostructures are correlated with the PEC and DHR efficiencies. Good PEC cell performance is identified to be related to topotactically formed samples with intimately connected particles that facilitate easy charge transfer. Additional benefit for PEC cell is found to be achieved from the vectorial conduction pathway in the pseudo one dimensional structure. On the other hand, high activity of DHR photocatalysis is attributed mainly to the exposed high reactivity crystal facets. The presence of anatase TiO2 {010} facets is identified to enhance electron‐hole separation and create specific surface states that facilitate interactions across the semiconductor/electrolyte interfaces.