Perovskite Nanocrystals Protected by Hermetically Sealing for Highly Bright and Stable Deep-Blue Light-Emitting Diodes.

Metal-halide perovskite nanocrystals (NCs) have emerged as suitable light-emitting materials for light-emitting diodes (LEDs) and other practical applications. However, LEDs with perovskite NCs undergo environment-induced and ion-migration-induced structural degradation during operation; therefore, novel NC design concepts, such as hermetic sealing of the perovskite NCs, are required. Thus far, viable synthetic conditions to form a robust and hermetic semiconducting shell on perovskite NCs have been rarely reported for LED applications because of the difficulties in the delicate engineering of encapsulation techniques.

Mn-Dopant Differentiating the Ru and Ir Oxidation States in Catalytic Oxides Toward Durable Oxygen Evolution Reaction in Acidic Electrolyte.

Designing an efficient and durable electrocatalyst for the sluggish oxygen evolution reaction (OER) at the anode remains the foremost challenge in developing proton exchange membrane (PEM) electrolyzers. Here, a highly active and durable cactus-like nanoparticle with an exposed heterointerface between the IrO and the low oxidation state Ru by introducing a trace amount of Mn dopant is reported. The heterostructure fabrication relies on initial mixing of the Ru and Ir phases before electrochemical oxidation to produce a conjoined Ru/IrO heterointerface.

Pt-Exchanged ZIF-8 nanocube as a solid-state precursor for L1-PtZn intermetallic nanoparticles embedded in a hollow carbon nanocage.

Nanoparticles with an atomically ordered alloy phase have received enormous attention for application as catalysts in fuel cells because of their unique electronic properties resulting from unusually strong d-orbital interactions between two metal components. However, the synthesis of intermetallic nanoparticles requires a high reaction temperature, thus necessitating the protection of nanoparticles with inorganic layers to prevent aggregation of nanoparticles during synthesis. The protective layer needs to be removed later for application as a catalyst, which is a cumbersome process.

Synthesis of nano-sized urchin-shaped LiFePO for lithium ion batteries.

In this article, the facile synthesis of sea urchin-shaped LiFePO nanoparticles by thermal decomposition of metal-surfactant complexes and application of these nanoparticles as a cathode in lithium ion secondary batteries is demonstrated. The advantages of this work are a facile method to synthesize interesting LiFePO nanostructures and its synthetic mechanism. Accordingly, the morphology of LiFePO particles could be regulated by the injection of oleylamine, with other surfactants and phosphoric acid.

Morphology-Controlled Metal Sulfides and Phosphides for Electrochemical Water Splitting.

Because H is considered a promising clean energy source, water electrolysis has attracted great interest in related research and technology. Noble-metal-based catalysts are used as electrode materials in water electrolyzers, but their high cost and low abundance have impeded them from being used in practical areas. Recently, metal sulfides and phosphides based on earth-abundant transition metals have emerged as promising candidates for efficient water-splitting catalysts.

Recent advances in electrocatalysts toward the oxygen reduction reaction: the case of PtNi octahedra.

Designing highly efficient and durable electrocatalysts for the oxygen reduction reaction (ORR), the key step for the operation of polymer electrolyte membrane fuel cells (PEMFCs), is of a pivotal importance for advancing PEMFC technology. Since the most significant progress has been made on Pt3Ni(111) alloy surfaces, nanoscale PtNi alloy octahedra enclosed by (111) facets have emerged as promising electrocatalysts toward the ORR. However, because their practical uses have been hampered by the cost, sluggish reaction kinetics, and poor durability, recent advances have engendered a wide variety of structure-, size-, and composition-controlled bimetallic PtNi octahedra.

NiOOH Exfoliation-Free Nickel Octahedra as Highly Active and Durable Electrocatalysts Toward the Oxygen Evolution Reaction in an Alkaline Electrolyte.

A layered β-NiOOH crystal with undercoordinated facets is an active and economically viable nonnoble catalyst for the oxygen evolution reaction (OER) in alkaline electrolytes. However, it is extremely difficult to enclose the β-NiOOH crystal with undercoordinated facets because of its inevitable crystal transformation to γ-NiOOH, resulting in the exfoliation of the catalytic surfaces. Herein, we demonstrate {111}-faceted Ni octahedra as the parent substrates whose surfaces are easily transformed to catalytically active β-NiOOH during the alkaline OER.