Synthesis of nanocrystals with exposed high-energy facets is a well-known challenge in many fields of science and technology. The higher reactivity of these facets simultaneously makes them desirable catalysts for sluggish chemical reactions and leads to their small populations in an equilibrated crystal. Using anatase TiO 2 as an example, we demonstrate a facile approach for creating high surface area, stable nanosheets comprised of nearly 100% exposed (001) facets. Our approach relies on spontaneous assembly of the nanosheets into three-dimensional, hierarchical spheres that stabilizes them from collapse. We show that the high surface density of exposed TiO 2 (001) facets leads to fast lithium insertion/deinsertion processes in batteries that mimic features seen in high power electrochemical capacitors.2

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SnO(2) nanoboxes with uniform morphology, good structural stability, and tunable interior volume can be facilely synthesized by template-engaged coordinating etching of pregrown Cu(2)O nanocubes at room temperature. When evaluated for their lithium storage properties, these SnO(2) nanoboxes manifest improved capacity retention.

We demonstrate a new hydrothermal method to directly grow SnO(2) nanosheets on a graphene oxide support that is subsequently reduced to graphene. This unique SnO(2)/graphene hybrid structure exhibits enhanced lithium storage properties with high reversible capacities and good cycling performance.

We have designed a unique hybrid structure by directly growing ultrathin anatase TiO(2) nanosheets onto graphene support for fast lithium storage. With exposed (001) high-energy facets, these TiO(2) nanosheets serve as ideal hosts for fast and efficient lithium storage. On the other hand, the graphene support serves as a highly conductive substrate that is beneficial to the high-rate performance.

Despite the significant advancement in making hollow structures, one unsolved challenge in the field is how to engineer hollow structures with specific shapes, tunable compositions, and desirable interior structures. In particular, top-down engineering the interiors inside preformed hollow structures is still a daunting task. In this work, we demonstrate a facile approach for the preparation of a variety of uniform hollow structures, including Cu(2)O@Fe(OH)(x) nanorattles and Fe(OH)(x) cages with various shapes and dimensions by template-engaged redox etching of shape-controlled Cu(2)O crystals. The composition can be readily modulated at different structural levels to generate other interesting structures such as Cu(2)O@Fe(2)O(3) and Cu@Fe(3)O(4) rattles, as well as Fe(2)O(3) and Fe(3)O(4) cages. More remarkably, this strategy enables top-down engineering the interiors of hollow structures as demonstrated by the fabrication of double-walled nanorattles and nanoboxes, and even box-in-box structures. In addition, this approach is also applied to form Au and MnO(x) based hollow structures.

Electrochemical water splitting is considered as a promising approach to produce clean and sustainable hydrogen fuel. As a new class of nanomaterials with high ratio of surface atoms and tunable composition and electronic structure, metal clusters are promising candidates as catalysts. Here, a new strategy is demonstrated to synthesize active and stable Pt‐based electrocatalysts for hydrogen evolution by confining Pt clusters in hollow mesoporous carbon spheres (Pt5/HMCS). Such a structure would effectively stabilize the Pt clusters during the ligand removal process, leading to remarkable electrocatalytic performance for hydrogen production in both acidic and alkaline solutions. Particularly, the optimal Pt5/HMCS electrocatalyst exhibits 12 times the mass activity of Pt in commercial Pt/C catalyst with similar Pt loading. This study exemplifies a simple yet effective approach to improve the cost effectiveness of precious‐metal‐based catalysts with stabilized metal clusters.

Polycrystalline α-Fe(2)O(3) nanotubes with thin walls have been synthesized by one-step template-engaged precipitation of Fe(OH)(x) followed by thermal annealing. In virtue of the unique structural features, these α-Fe(2)O(3) nanotubes exhibit superior lithium storage capabilities with exceptional high-rate capacity retention as a potential anode material for lithium-ion batteries.