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The development of environmentally sustainable and highly efficient technologies for ammonia production is crucial for the future advancement of carbon‐neutral energy systems. The nitrite reduction reaction (NO2RR) for generating NH3 is a promising alternative to the low‐efficiency nitrogen reduction reaction (NRR), owing to the low N=O bond energy and high solubility of nitrite. In this study, we designed a highly efficient dual‐atom catalyst with Fe‐Cu atomic pair sites (termed FeCu DAC), and the as‐developed FeCu DAC was able to afford a remarkable NH3 yield of 24,526 μg h−1 mgcat.−1 at −0.6 V, with a Faradaic Efficiency (FE) for NH3 production of 99.88 %. The FeCu DAC also exhibited exceptional catalytic activity and selectivity in a Zn‐NO2 battery, achieving a record‐breaking power density of 23.6 mW cm−2 and maximum NH3 FE of 92.23 % at 20 mA cm−2. Theoretical simulation demonstrated that the incorporation of the Cu atom changed the energy of the Fe 3d orbital and lowered the energy barrier, thereby accelerating the NO2RR. This study not only demonstrates the potential of galvanic nitrite‐based cells for expanding the field of Zn‐based batteries, but also provides fundamental interpretation for the synergistic effect in highly dispersed dual‐atom catalysts. [ABSTRACT FROM AUTHOR]

Combining morphological control engineering and diatomic coupling strategies, heteronuclear Fe-Co bimetals are efficiently intercalated into nitrogen-doped carbon materials with star-like to simultaneously accelerate oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The half-wave potential and kinetic current density of the ORR driven by FeCoNC/SL surpass the commercial Pt/C catalyst. The overpotential of OER is as low as 316 mV (/10), and the mass activity is at least 3.2 and 9.4 times that of mononuclear CoNC/SL and FeNC/SL, respectively. The power density and specific capacity of the Zn-air battery with FeCoNC/SL as air cathode are as high as 224.8 mW cm-2 and 803 mAh g-1, respectively. Morphologically, FeCoNC/SL endows more reactive sites and accelerates the process of oxygen reaction. Density functional theory reveals the active site of the heteronuclear diatomic, and the formation of FeCoN5C configuration can effectively tune the d-band center and electronic structure. The redistribution of electrons provides conditions for fast electron exchange, and the change of the center of the d-band avoids the strong adsorption of intermediate species to simultaneously take into account both ORR and OER and thus achieve high-performance Zn-air batteries. [ABSTRACT FROM AUTHOR]

Over the past few decades, the design and development of carbon materials have occurred at a rapid pace. In particular, these porous graphene‐like carbon nitride materials have received considerable attention due to their superior structures and performances in the energy transformation field. In this review, nitrogenated holey two‐dimensional graphene and polymeric carbon nitride will be discussed in depth. The structural properties, synthetic methods, and applications including electrocatalytic reactions, such as hydrogen evolution reaction, oxygen reduction reaction, oxygen evolution reaction, and nitrogen reduction reaction, will be presented in detail. Finally, we will present the outlooks on the current obstacles to the development of carbon nitride materials. This comprehensive understanding will help guide and motivate researchers to develop and modify carbon nitride materials with better properties in the future. [ABSTRACT FROM AUTHOR]