Reversible dendrite-free low-areal-capacity lithium metal electrodes have recently been revived, because of their pivotal role in developing beyond lithium ion batteries. However, there have been no reports of reversible dendrite-free high-areal-capacity lithium metal electrodes. Here we report on a strategy to realize unprecedented stable cycling of lithium electrodeposition/stripping with a highly desirable areal-capacity (12 mAh cm−2) and exceptional Coulombic efficiency (>99.98%) at high current densities (>5 mA cm−2) and ambient temperature using a diluted solvate ionic liquid. The essence of this strategy, that can drastically improve lithium electrodeposition kinetics by cyclic voltammetry premodulation, lies in the tailoring of the top solid-electrolyte interphase layer in a diluted solvate ionic liquid to facilitate a two-dimensional growth mode. We anticipate that this discovery could pave the way for developing reversible dendrite-free metal anodes for sustainable battery chemistries.

Monodisperse manganese oxide flowerlike nanostructures have been prepared facilely at low temperature and ambient atmosphere. The effect of the reaction time on the microstructure and morphology is observed systemically by transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). Meanwhile, the possible formation mechanism of the flowerlike nanostructures has been proposed and discussed. It is also found that the reaction temperature has great influences on the morphology of these unique nanostructures. The results of nitrogen adsorption-desorption experiments and electrochemical measurements show that the product obtained at 40 °C for 8 h has large specific surface area, uniform pore size distribution, and excellent capacitance performance, which make it a potential supercapacitor electrode material.

The facile synthesis of mesoporous g-alumina is developed through the partial hydrolysis of Al(NO 3 ) 3 aqueous solution with (NH 4 ) 2 CO 3 without organic surfactants. In this synthesis, the stable NH 4 NO 3 / Al species (AN/Al) hybrid containing Keggin-Al 13 polycations is first prepared, which is the key for the successful formation of mesoporous g-alumina. XRD, 27 Al MAS NMR, TEM, and N 2 adsorption and desorption results demonstrate that the as-prepared AN/Al hybrid can be transformed to g-alumina by treatment at 200 C and exhibit a wormhole-like mesoporous structure with large surface area up to $450 m 2 g À1 , pore volume of $0.3 cm 3 g À1 and narrow pore size distribution peaked at $3.9 nm after completely removing NH 4 NO 3 at 300 C. The obtained mesoporous g-aluminas have high thermal stabilities up to 900 C and excellent hydrothermal stability. The investigation shows that the synergetic effect of NH 4 NO 3 and Al 13 species promotes crystallization of Al species to g-alumina, which may have a unique mechanism distinct from the mesoporous aluminas reported previously. CO 2 adsorption measurements indicate that these mesoporous g-aluminas have a much higher CO 2 adsorption capacity than ordered mesoporous alumina synthesized by the surfactant-templating method and conventional g-alumina derived from aluminum oxyhydroxides. We believe that this research should be useful for providing new insights into the transformation of transition alumina phases and for synthesizing mesoporous g-alumina with promising properties for various chemical applications.

Hierarchical cantaloupe-like and hollow microspherical AlOOH superstructures were successfully synthesized on a large scale via a one-step hydrothermal route. The as-obtained superstructures were characterized by several techniques, such as X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and nitrogen adsorption/ desorption measurement. The as-obtained superstructures, consisting of closely packed nanorods in an ordered fashion, have an average horizontal axis of ca. 2.5 µm and a longitudinal axis of ca. 1.5 µm. The as-obtained cantaloupe-like AlOOH superstructures have Brunauer-Emmett-Teller (BET) surface area of about 55.5 m 2 /g. The possible formation mechanism of the cantaloupe-like AlOOH superstructures is proposed and discussed.

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