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Zirconia as a polycrystalline catalyst can be effectively tuned by doping low-valence elements and meanwhile form abundant oxygen vacancies. Herein, the crystalline structures of zirconia are modulated by scandium doping and proposed as a robust catalyst for nitrate reduction to ammonia. The tetragonal zirconia achieves a maximum ammonia yield of 16.03 mg h -1 mg cat. -1 , superior to the other crystal forms. DEMS tests unveil the reaction pathway and theoretical calculations reveal the low free energy of -0.22 eV for nitrate adsorption at the tetragonal zirconia.

The nitrate reduction reaction is emerging as having tremendous potential to mitigate nitrate pollution and simultaneously produce valuable ammonia. Here, we propose Co 3 O 4 nanoparticles embedded in porous carbon nanofibers (Co 3 O 4 @CNF) as a high-efficiency catalyst to convert nitrate to ammonia, and it achieves a high faradaic efficiency of 92.7% and an extremely large NH 3 yield of 23.4 mg h -1 mg -1 cat , and also presents excellent electrochemical stability. Theoretical calculations reveal that the potential determining step (PDS) reaches as low as 0.28 eV. This work is expected to open a new avenue to rationally design robust noble-metal-free catalysts for the electrochemical synthesis of ammonia.

In this study, we construct a Cu@ZrO 2 heterogenous structure as a new catalyst that achieves a large NH 3 yield of 15.4 mg h -1 mg -1 cat . and a high faradaic efficiency of 67.6% at -0.7 V vs. RHE in 0.1 M PBS with 0.1 M NaNO 3 , and it also shows excellent electrochemical durability and structural stability. Theoretical calculations reveal an extremely low adsorption energy of -1.54 eV at Cu surfaces and Cu can significantly reduce the applied overpotential and correspondingly promote the catalytic activity.

Self-supported materials have been widely used in high-power energy storage devices due to the unique construction offering fast charge transfer from the active material to the conducting substrate. However, the electron conduction in the active material presents limitations on the overall performance of the electrode. In this work, we have fabricated hierarchical ZnO nanoflake arrays vertically grown on a nickel foam substrate and wrapped tightly by wrinkled porous CoS nanofilms (ZnO NFAs/CoS NFs) via a hydrothermal process and subsequent electrodeposition. Such an optimized ZnO NFAs/CoS NFs electrode exhibits an excellent specific capacitance of 1416 F g -1 at a current density of 1 A g -1 , and remarkable cycling stability with 85.3% retention of the initial capacitance at 10 A g -1 after 5000 cycles. Additionally, density functional theory (DFT) calculations have been performed to further investigate the mechanism, proving the facilitated electron transfer from CoS to ZnO, giving rise to the superior electrochemical performance.

Yolk/shell or 'rattle-typed' nanomaterials with nanoparticle cores inside hollow shells are interesting among the complex hollow nanostructures. Yolk/shell nanoparticles (YSNs) are promising functional nanomaterials for a variety of applications such as catalysis, delivery, lithium-ion batteries and biosensors due to their tailorability and functionality in both the cores and hollow shells. This feature article provides an overview of advances in this exciting area of YSNs, covering systematic synthesis approaches and key promising applications based on the literature and our own recent work. We present some strategies for the synthesis of YSNs with controllable sizes, compositions, geometries, structures and functionalities. Applications of these new materials in a wide range of potential areas are discussed including nanoreactors, biomedicine and lithium-ion batteries. Promising future directions of this active research field are also highlighted.

We demonstrate an unusual formation of large 2D nanosheets from nanomosaic building blocks of anatase TiO(2) nanosheets with exposed (001) facets. It is proposed that large PVP molecules adsorbed on the (001) facets serve as the linker that brings building blocks together, at the same time prevents them from stacking along the c-axis., (This journal is © The Royal Society of Chemistry 2011)

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., (This journal is © The Royal Society of Chemistry 2011)

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., (© The Royal Society of Chemistry 2011)

A simple approach was proposed to synthesize three types of ellipsoidal hollow nanostructures whose shells are assembled from anatase TiO(2) nanosheets (NSs) with exposed (001) facets. Among them, ellipsoid Fe(3)O(4)@TiO(2)-NS nanorattles can be readily generated as a magnetically separable photocatalyst with enhanced activity through in situ reduction of the α-Fe(2)O(3) core.

TiO(2) and SnO(2)@TiO(2) hollow spheres assembled from anatase TiO(2) nanosheets with exposed (001) high-energy facets are constructed via a templating approach, and the as-prepared samples exhibit enhanced lithium storage properties.

Uniform carbon-coated MoO(2) nanospheres assembled from small primary nanocrystals have been synthesized by a one-pot hydrothermal method followed by thermal annealing. Because of the desirable structural features, these core-shell MoO(2)@carbon nanospheres exhibit significantly improved electrochemical performance for high-rate reversible lithium storage.

Anatase TiO(2) having different percentages of (001)/(101) surface demonstrated different behaviors for Li(+) ions insertion and much enhanced rate performance of Li-ion batteries.