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Here, a novel N,B-doped graphene aerogel, abbreviated as N,B-GA, was obtained via a two-step approach and served as a metal-free catalyst for the oxygen reduction reaction (ORR). This two-step method involved a hydrothermal reaction and a pyrolysis procedure, guaranteeing the efficient insertion of the heteroatoms. The resulting three-dimensional (3D) N,B-GA obtained at pyrolysis temperature of 1000 °C exhibited outstanding catalytic activity for the oxygen reduction reaction (ORR), comparable to that of Pt/C. In addition, the catalytic activity of this 3D N,B-GA was obviously better than that of the nitrogen-doped graphene aerogel (N-GA) and boron-doped graphene aerogel (B-GA) in terms of the onset potential, half-wave potential and diffusion limiting current density. The superior catalytic reactivity arises from the synergistic coupling of the B and N dopants within the graphene domains.

Metastable zinc blende CuInSe(2) nanocrystals were synthesized by a hot-injection approach. It was found that the lattice mismatches between zinc blende CuInSe(2) and ZnSe as well as CuInSe(2) and CuInS(2) are only 2.0% and 4.6%, respectively. Thus, alloyed (ZnSe)(x)(CuInSe(2))(1-x) and CuInSe(x)S(2-x) nanocrystals with a zinc blende structure have been successfully synthesized over the entire composition range, and the band gaps of alloys can be tuned in the range from 2.82 to 0.96 eV and 1.43 to 0.98 eV, respectively. These alloyed (ZnSe)(x)(CuInSe(2))(1-x) and CuInSe(x)S(2-x) nanocrystals with a broad tunable band gap have a high potential for photovoltaic and photocatalytic applications.

Developing efficient, inexpensive, and durable electrocatalysts for the oxygen reduction reaction (ORR) is important for the large‐scale commercialization of fuel cells and metal–air batteries. Herein, a hierarchically porous bimetallic Fe/Co single‐atom‐coordinated N‐doped carbon (Fe/Co‐Nx‐C) electrocatalyst for ORR is synthesized from Fe/Co‐coordinated polyporphyrin using silica template‐assisted and silica‐protection synthetic strategies. In the synthesis, first silica nanoparticles‐embedded, silica‐protected Fe/Co‐polyporphyrin is prepared. It is then pyrolyzed and treated with acidic solution. The resulting Fe/Co‐Nx‐C material has a large specific surface area, large electrochemically active surface area, good conductivity, and catalytically active Fe/Co‐Nx sites. The material exhibits a very good electrocatalytic activity for the ORR in alkaline media, with a half‐wave potential of 0.86 V versus reversible hydrogen electrode, which is better than that of Pt/C (20 wt%). Furthermore, it shows an outstanding operational stability and durability during the reaction. A zinc–air battery (ZAB) assembled using Fe/Co‐Nx‐C as an air‐cathode electrocatalyst gives a high peak power density (152.0 mW cm−2) and shows a good recovery property. Furthermore, the performance of the battery is better than a corresponding ZAB containing Pt/C as an electrocatalyst. The work also demonstrates a synthetic route to a highly active, stable, and scalable single‐atom electrocatalyst for ORR in ZABs.

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