Manipulation of Electron Spins with Oxygen Vacancy on Amorphous/Crystalline Composite-Type Catalyst.

By substituting the oxygen evolution reaction (OER) with the anodic urea oxidation reaction (UOR), it not only reduces energy consumption for green hydrogen generation but also allows purification of urea-rich wastewater. Spin engineering of the d orbital and oxygen-containing adsorbates has been recognized as an effective pathway for enhancing the performance of electrocatalysts. In this work, we report the fabrication of a bifunctional electrocatalyst composed of amorphous RuO-coated NiO ultrathin nanosheets (a-RuO/NiO) with abundant amorphous/crystalline interfaces for hydrogen evolution reaction (HER) and UOR.

Engineering Amorphous/Crystalline Ru(OH)/CoFe-Layered Double Hydroxide for Hydrogen Evolution at 1000 mA cm.

For large-scale industrial applications, it is highly desirable to create effective, economical electrocatalysts with long-term stability for the hydrogen evolution reaction (HER) at a large current density. Herein, we report a unique motif with crystalline CoFe-layered hydroxide (CoFe-LDH) nanosheets enclosed by amorphous ruthenium hydroxide (a-Ru(OH)/CoFe-LDH) to realize the efficient hydrogen production at 1000 mA cm, with a low overpotential of 178 mV in alkaline media. During the continuous HER process for 40 h at such a large current density, the potential remains almost constant with only slight fluctuations, indicating good long-term stability.

Pseudopyrolysis of Metal-Organic Frameworks: A Synchronous Nucleation Mechanism to Synthesize Ultrafine Metal Compound Nanoparticles.

Metal-Organic frameworks (MOFs) are increasingly being investigated for the synthesis of carbon-supported metal-based ultrafine nanoparticles (UNPs). However, the collapse of the carbon framework and aggregation of metal particles in the pyrolysis process have severely hindered their stability and applications. Here, we report the synchronous nucleation pseudopyrolysis of MOFs to confine Fe/FeO UNPs in intact porous carbon nanorods (IPCNs), revealed by in situ transmission electron microscopy experiments and ex situ structure analysis.

Engineering Amorphous/Crystalline Rod-like Core-Shell Electrocatalysts for Overall Water Splitting.

The design of bifunctional electrocatalysts for hydrogen and oxygen evolution reactions delivering excellent catalytic activity and stability is highly desirable, yet challenged. Herein, we report an amorphous RuO-encapsulated crystalline NiSe nanorod structure (termed as a/c-RuO/NiSe) for enhanced HER and OER activities. The as-prepared a/c-RuO/NiSe nanorods not only demonstrate splendid HER activity (58 mV@10 mA cm vs RHE), OER activity (233 mV@10 mA cm vs RHE), and electrolyzer activity (1.

Boosting Charge Transfer Via Heterostructure Engineering of Ti CT /Na Ti O Nanobelts Array for Superior Sodium Storage Performance.

The poor conductivity, inert charge transmission efficiency, and irreversible Na trapping of Na Ti O result in retardant electrons/ions transportation and deficient sodium-ion storage efficiency, leading to sluggish reaction kinetics. To address these issues, an urchin-like Ti CT /Na Ti O (Ti C/NTO) heterostructure sphere consisting of Ti C/NTO heterostructure nanobelts array is developed via a facile one-step in situ hydrothermal strategy. The Ti C/NTO heterostructure can obviously decrease Na diffusion barriers and increase electronic conductivity to improve reaction kinetics due to the built-in electric field effect and high-quantity interface region.

Promoting photocatalytic hydrogen evolution over the perovskite oxide Pr(BaSr)CoFeO by plasmon-induced hot electron injection.

Exploration of highly efficient and stable photocatalysts for water splitting has attracted much attention. However, developing a facile and effective approach to enhance the photocatalytic activity for practical applications is still highly challenging. Herein, we report a newly-fabricated perovskite oxide (Pr(BaSr)CoFeO) decorated with Au ultrafine nanoparticles for photocatalytic water splitting.

Ultralarge elastic deformation of nanoscale diamond.

Diamonds have substantial hardness and durability, but attempting to deform diamonds usually results in brittle fracture. We demonstrate ultralarge, fully reversible elastic deformation of nanoscale (~300 nanometers) single-crystalline and polycrystalline diamond needles. For single-crystalline diamond, the maximum tensile strains (up to 9%) approached the theoretical elastic limit, and the corresponding maximum tensile stress reached ~89 to 98 gigapascals.

Nickel-Cobalt Diselenide 3D Mesoporous Nanosheet Networks Supported on Ni Foam: An All-pH Highly Efficient Integrated Electrocatalyst for Hydrogen Evolution.

Novel 3D Ni Co Se mesoporous nanosheet networks with tunable stoichiometry are successfully synthesized on Ni foam (Ni Co Se MNSN/NF with x ranging from 0 to 0.35). The collective effects of special morphological design and electronic structure engineering enable the integrated electrocatalyst to have very high activity for hydrogen evolution reaction (HER) and excellent stability in a wide pH range.

Mesoporous SnO Nanostructures of Ultrahigh Surface Areas by Novel Anodization.

Here we report a novel type of hierarchical mesoporous SnO nanostructures fabricated by a facile anodization method in a novel electrolyte system (an ethylene glycol solution of HCO/NHF) followed by thermal annealing at a low temperature. The SnO nanostructures thus obtained feature highly porous nanosheets with mesoporous pores well below 10 nm, enabling a remarkably high surface area of 202.8 m/g which represents one of the highest values reported to date on SnO nanostructures.

Intracellular Delivery: Diamond-Nanoneedle-Array-Facilitated Intracellular Delivery and the Potential Influence on Cell Physiology (Adv. Healthcare Mater. 10/2016).

G. Zhu, W. Zhang, X.

Bactericidal activity of biomimetic diamond nanocone surfaces.

The formation of biofilms on implant surfaces and the subsequent development of medical device-associated infections are difficult to resolve and can cause considerable morbidity to the patient. Over the past decade, there has been growing recognition that physical cues, such as surface topography, can regulate biological responses and possess bactericidal activity. In this study, diamond nanocone-patterned surfaces, representing biomimetic analogs of the naturally bactericidal cicada fly wing, were fabricated using microwave plasma chemical vapor deposition, followed by bias-assisted reactive ion etching.

Diamond-Nanoneedle-Array-Facilitated Intracellular Delivery and the Potential Influence on Cell Physiology.

Vertical arrays of nanostructures can provide access to the cell cytoplasma and probe intracellular molecules. Here, the simple combination of diamond nanoneedle arrays with centrifugation-induced supergravity is shown to efficiently deliver drugs and biomaterials into the cytosol within several minutes, negotiating the endocytososomal system. The potential influence of the technique on cell metabolism is thoroughly studied.

Electrochemical Energy Storage Application and Degradation Analysis of Carbon-Coated Hierarchical NiCo2S4 Core-Shell Nanowire Arrays Grown Directly on Graphene/Nickel Foam.

We developed a new electrode comprising thin carbon layer coated hierarchical NiCo2S4 core-shell nanowire arrays (NiCo2S4@C CSNAs) on graphene/Ni foam (Ni@G) substrates. The electrode showed outstanding electrochemical characteristics including a high specific capacitance of 253 mAh g(-1) at 3 A g(-1), high rate capability of 163 mAh g(-1) at 50 A g(-1) (~64.4% of that at 3 A g(-1)), and long-term cycling stability with a capacity retention of 93.

Dendritic heterojunction nanowire arrays for high-performance supercapacitors.

Herein, we designed and synthesized for the first time a series of 3D dendritic heterojunction arrays on Ni foam substrates, with NiCo2S4 nanowires as cores and NiCo2O4, NiO, Co3O4, and MnO2 nanowires as branches, and studied systematically their electrochemical performance in comparison with their counterparts in core/shell structure. Attributed to the following reasons: (1) both core and branch are pseudocapacitively active materials, (2) the special dendritic structure with considerable inter-nanowire space enables easy access of electrolyte to the core and branch surfaces, and (3) the highly conductive NiCo2S4 nanowire cores provide "superhighways" for charge transition, NiCo2S4-cored dendritic heterojunction electrodes synergistically lead to ultrahigh specific capacitance, good rate capability, and excellent cycling life. These results of core/branch dentritic heterojunction arrays is universially superior to their core/shell conterparts, thus this is a significant improvement of overall electrochemical performance.