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Lithium‐rich manganese‐based layered oxides show great potential as high‐capacity cathode materials for lithium ion batteries, but usually exhibit a poor cycle life, gradual voltage drop during cycling, and low thermal stability in the highly delithiated state. Herein, a strategy to promote the electrochemical performance of this material by manipulating the electronic structure through incorporation of boracic polyanions is developed. As‐prepared Li[Li0.2Ni0.13Co0.13Mn0.54](BO4)0.015(BO3)0.005O1.925 shows a decreased M‐O covalency and a lowered O 2p band top compared with pristine Li[Li0.2Ni0.13Co0.13Mn0.54]O2. As a result, the modified cathode exhibits a superior reversible capacity of 300 mA h g−1 after 80 cycles, excellent cycling stability with a capacity retention of 89% within 300 cycles, higher thermal stability, and enhanced redox couple potentials. The improvements are correlated to the enhanced oxygen stability that originates from the tuned electronic structure. This facile strategy may further be extended to other high capacity electrode systems.

lithography process, using the increase in the T g of the photoresist particles caused by UV-induced crosslinking. Subsequent deposition of silica through the patterned-colloidal mask yielded ordered domains of nanoscale-hole arrays on a micrometer length scale. The present technique produces a spatially organized mask with multiple length scales for colloidal lithography. As such, various functional materials can be deposited through these multiscale colloidal masks, fabricating nanopatterned substrates, which are of practical significance in a wide range of applications from biosensors to optoelectronic devices. ExperimentalSynthesis of Photoresist Particles: MMA (Aldrich, > 99 %) and GMA (Aldrich, > 95 %) were used as supplied. Potassium persulfate (KPS) was used as an initiator for emulsion polymerization. A 100 mL two-necked round-bottom flask was filled with KPS dissolved in 50 mL of distilled water, and a monomer mixture of MMA and GMA. The content of KPS was fixed at 1 wt.-%. The content of GMA was varied in the range 5-30 wt.-% of the total monomer content, which was fixed at 10 wt.-%. The system was kept under a nitrogen atmosphere and the reaction mixture was stirred magnetically at 300 rpm. When the KPS was dissolved completely, the mixture was heated to 75°C using an oil bath. After 12 h, the mixture was separated by centrifugation and was purified with distilled water several times. The size of the particles, measured by SEM, ranged from 360 to 420 nm. Later, the cationic photoinitiator, Irgacure 250, was introduced to the photoresist particles by spin-coating.Measurement of T g : The glass-transition temperatures of the UV-exposed and UV-screened poly(MMA-co-GMA) particles were determined using a differential scanning calorimeter (DSC, TA Instruments, Q1000) under a nitrogen atmosphere at a heating rate of 10°C min -1 . To measure the T g of UV-exposed particles, the particles were fully baked at 150°C for 2 h after UV exposure, because the crosslinking reaction could proceed during the DSC measurement. Therefore, the measured T g could be higher than the T g of the UV-exposed particles in the patterning. Meanwhile, T g of the UV-screened particles was compared with that estimated using the rule-of-mixtures theory where T g = 115°C for polyMMA and T g = 75°C for polyGMA [19].Deposition of Silica: Silica was deposited in a batch reactor under atmospheric pressure at room temperature. The sample was sequentially exposed to water vapor for 30 min, dried in argon gas for purging the reactor, and then SiCl 4 vapor for 20 min. The reactant vapors were carried by argon gas under atmospheric pressure. The concentration of SiCl 4 was 0.05 vol.-% in moisture-free argon gas and the relative humidity of water vapor was 50 %. (Caution: silicon tetrachloride is a very corrosive liquid. Use it only with adequate ventilation, and wear protective clothing and safety goggles.) The thickness of the silica layer was controlled by the exposure time to the precursor vapor and around 50 nm for 30 min exposure was obtained.

Prolonging the lifetime of superhydrophobic surfaces is required so that the materials can be used practically. Thus, great efforts have been made in designing surfaces that maintain micro-and nanoscaled hierarchical structures and low surface-energy property, which are necessary for superhydrophobicity, during use. It was demonstrated that improving surface mechanical strength to increase wear resistance helps maintain hierarchical roughness, retarding the loss of superhydrophobicity. Additionally, designing self-healing materials that can recover their structure and/ or properties when damaged has been suggested and demonstrated to sustain the superhydrophobicity of surfaces. This review focuses on recent advances in developing mechanically durable, corrosionresistant, self-healing, and easily repairable superhydrophobic surfaces, which will enable prolonged lifetime of superhydrophobicity for practical applications in the future.