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The development of Fe single‐atom catalysts (Fe SACs) with abundant, accessible Fe sites is a key step toward enhancing the efficiency of the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs). In this study, Zn4O(1,4‐benzenedicarboxylate)3 (MOF‐5), which has a 3D microporous cubic structure, is used as the precursor to prepare highly‐porous carbon (denoted as C‐MOF‐5) with an ultrahigh specific surface area (2751 m2 g–1) and high external surface area (1651 m2 g–1). C‐MOF‐5 is demonstrated as an effective carbon support to yield Fe SAC‐MOF‐5 with a large amount of accessible FeNx sites (2.35 wt%). Fe SAC‐MOF‐5 delivers a half‐wave potential of 0.83 V (vs RHE) in a 0.5 m H2SO4 electrolyte, and achieves a peak power density of 0.84 W cm–2 in a 0.2 MPa H2‐O2 PEMFC. This excellent performance originates from the ultrahigh specific surface area of C‐MOF‐5 for the formation of a high density of single Fe atoms, and high external surface area for the increased exposure of active sites. This work may inspire the rational design of metal single‐atom catalysts derived from a wider range of MOF precursors with ultrahigh specific area to improve the performance of the oxygen reduction reaction in PEMFCs. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) is an environmentally friendly oxidant, finding widespread use across the chemical industry, in sanitation and environmental remediation. Currently, H2O2 is manufactured via the anthraquinone process which has a number of disadvantages including nondistributed production, high‐energy consumption, substantial organic by‐product waste, and the need to transport the obtained H2O2 to the point‐of‐use. Accordingly, the electrochemical synthesis of H2O2 is now attracting a lot of interest as an alternative, cost‐effective, small‐scale, and distributed technology for H2O2 manufacture. This review summarizes recent advancements in the development of Homogeneous and Heterogeneous catalysts for electrocatalytic O2 reduction reaction (ORR) to H2O2. The basic principles of the ORR, and methodologies for investigating the ORR to H2O2 are first introduced. Next, H2O2 production over Homogeneous catalysts is discussed, with a focus on the reaction mechanisms and the factors that influence activity, selectivity, and reaction kinetics. Subsequently, recent breakthroughs in H2O2 synthesis over Heterogeneous catalysts, including nonnoble metal‐based nanomaterials, carbon materials, and single‐atom catalysts are described. The latter are given special attention, since they serve as a bridge between Homogeneous catalysis and Heterogeneous catalysis, while also offering excellent performance. Finally, the challenges and opportunities for electrochemical ORR to H2O2 are critically discussed. [ABSTRACT FROM AUTHOR]

Abstract: Transition metal nitrides (TMNs) inevitably aggregate in the high‐temperature thermal ammonolysis process, resulting in blocking of the active catalytic sites and serious decreases in their corresponding catalytic performance. Therefore, how to synthesize ultrasmall TMNs with higher exposed unsaturated coordination sites is still a challenge. Herein, ultrathin Ni3FeN (Ni3FeN@SiO2) with the size of ≈20 nm and thickness of ≈3.0 nm is fabricated by SiO2 protection strategy. The obtained Ni3FeN@SiO2 displays outstanding performance in NH3BH3 hydrolytic dehydrogenation due to the high specific surface area, intrinsic metal‐vacancies, and hydrophilic SiO2 layer. [ABSTRACT FROM AUTHOR]

Ni3FeN nanoparticles with a particle size of ≈100 nm and a thickness of ≈9 nm are successfully synthesized by thermal ammonolysis of ultrathin NiFe‐layered double hydroxide ultrathin nanosheets. The Ni3FeN nanoparticles exhibit excellent catalytic performance and high stability in electrochemical overall water splitting. [ABSTRACT FROM AUTHOR]

CdS nanoparticle‐decorated Cd nanosheets (CdS NP/Cd NSs) are successfully ­fabricated for the first time via a facile oxidation–sulfurization treatment of Cd nanosheets. Due to the high electrical conductivity and visible light reflectivity of Cd nanosheets, the obtained CdS NP/Cd NSs heterostructures show significantly enhanced activities for visible light‐driven photocatalytic H2 production compared to other reference CdS photocatalysts. [ABSTRACT FROM AUTHOR]

Abstract: Transition metal nitrides (TMNs) inevitably aggregate in the high‐temperature thermal ammonolysis process, resulting in blocking of the active catalytic sites and serious decreases in their corresponding catalytic performance. Therefore, how to synthesize ultrasmall TMNs with higher exposed unsaturated coordination sites is still a challenge. Herein, ultrathin Ni3FeN (Ni3FeN@SiO2) with the size of ≈20 nm and thickness of ≈3.0 nm is fabricated by SiO2 protection strategy. The obtained Ni3FeN@SiO2 displays outstanding performance in NH3BH3 hydrolytic dehydrogenation due to the high specific surface area, intrinsic metal‐vacancies, and hydrophilic SiO2 layer. [ABSTRACT FROM AUTHOR]