Ambient electrochemical N2 reduction is emerging as a highly promising alternative to the Haber–Bosch process but is typically hampered by a high reaction barrier and competing hydrogen evolution, leading to an extremely low Faradaic efficiency. Here, we demonstrate that under ambient conditions, a single-atom catalyst, iron on nitrogen-doped carbon, could positively shift the ammonia synthesis process to an onset potential of 0.193 V, enabling a dramatically enhanced Faradaic efficiency of 56.55%. The only doublet coupling representing 15NH4+ in an isotopic labeling experiment confirms reliable NH3 production data. Molecular dynamics simulations suggest efficient N2 access to the single-atom iron with only a small energy barrier, which benefits preferential N2 adsorption instead of H adsorption via a strong exothermic process, as further confirmed by first-principle calculations. The released energy helps promote the following process and the reaction bottleneck, which is widely considered to be the first hydrogenation step, is successfully overcome.

A sustainable route from the biomass byproduct okara as a natural nitrogen fertilizer to high-content N-doped carbon sheets is demonstrated. The as-prepared unique structure exhibits high specific capacity (292 mAh g(-1) ) and extremely long cycle life (exceeding 2000 cycles). A full battery is devised for the practical use of materials with a flexible/wearable LED screen.

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Covalent organic frameworks with abundant active sites are potential metal-free catalysts for the nitrogen reduction reaction. However, the utilization ratio of active sites is restricted in an actual reaction process due to the limited nitrogen transport. Here, we demonstrate that facilitating the N 2 accessibility to boron-rich covalent organic frameworks through electrochemical excitation can achieve highly efficient nitrogen reduction activity. Simulations show that the boron sites are bonded with nitrogenous species under electrochemical condition and the resultant amorphous phase of covalent organic frameworks has much stronger affinity toward N 2 to enhance the molecule collision. Combined with experimental results, the excitation process is confirmed to be a virtuous cycle of more excited sites and stronger N 2 affinity, which continuously proceed until the whole system reaches the optimum reaction status. As expected, the electrochemically excited catalyst delivers significantly enhanced reaction activity, with a high Faradaic efficiency of 45.43%.

We report a new paradigm for the rational design of chiral nanostructures that is based on the hierarchical self-assembly of a ferrocene (Fc)-modified dipeptide, ferrocene-L-Phe-L-Phe-OH (Fc-FF). Compared to other chiral self-assembling systems, Fc-FF is unique because of its smaller size, biocompatibility, multiple functions (a redox center), and environmental responsiveness. X-ray and spectroscopic analyses showed that the incorporation of counterions during the hierarchical self-assembly of Fc-FF changed the conformations of the secondary structures from flat β sheets into twisted β sheets. This approach enables chiral self-assembly and the formation of well-defined chiral nanostructures composed of helical twisted β sheets. We identified two elementary forms for the helical twist of the β sheets, which allowed us to create a rich variety of rigid chiral nanostructures over a wide range of scales. Furthermore, through subtle modulations in the counterions, temperature, and solvent, we are able to precisely control the helical pitch, diameter, and handedness of the self-assembled chiral nanostructures. This unprecedented level of control not only offers insights into how rationally designed chiral nanostructures can be formed from simple molecular building blocks but also is of significant practical value for the use in chiroptics, templates, chiral sensing, and separations.