The industrial artificial fixation of atmospheric N2 to NH3 is carried out using the Haber–Bosch process that is not only energy‐intensive but emits large amounts of greenhouse gas. Electrochemical reduction offers an environmentally benign and sustainable alternative for NH3 synthesis. Although Mo‐dependent nitrogenases and molecular complexes effectively catalyze the N2 fixation at ambient conditions, the development of a Mo‐based nanocatalyst for highly performance electrochemical N2 fixation still remains a key challenge. Here, greatly boosted electrocatalytic N2 reduction to NH3 with excellent selectivity by defect‐rich MoS2 nanoflowers is reported. In 0.1 m Na2SO4, this catalyst attains a high Faradic efficiency of 8.34% and a high NH3 yield of 29.28 µg h−1 mg−1cat. at −0.40 V versus reversible hydrogen electrode, much larger than those of defect‐free counterpart (2.18% and 13.41 µg h−1 mg−1cat.), with strong electrochemical stability. Density functional theory calculations show that the potential determining step has a lower energy barrier (0.60 eV) for defect‐rich catalyst than that of defect‐free one (0.68 eV).

The detection of glucose has important significance in clinical medicine and food industry, especially in the diagnosis of diabetes. In recent years, electrochemical non-enzymatic glucose sensors have attracted intensive attention...

Electrocatalytic two‐electron oxygen reduction has emerged as a promising alternative to the energy‐ and waste‐intensive anthraquinone process for distributed H2O2 production. This process, however, suffers from strong competition from the four‐electron pathway leading to low H2O2 selectivity. Herein, we report using a superhydrophilic O2‐entrapping electrocatalyst to enable superb two‐electron oxygen reduction electrocatalysis. The honeycomb carbon nanofibers (HCNFs) are robust and capable of achieving a high H2O2 selectivity of 97.3 %, much higher than that of its solid carbon nanofiber counterpart. Impressively, this catalyst achieves an ultrahigh mass activity of up to 220 A g−1, surpassing all other catalysts for two‐electron oxygen reduction reaction. The superhydrophilic porous carbon skeleton with rich oxygenated functional groups facilitates efficient electron transfer and better wetting of the catalyst by the electrolyte, and the interconnected cavities allow for more effective entrapping of the gas bubbles. The catalytic mechanism is further revealed by in situ Raman analysis and density functional theory calculations.

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NiCo2O4 nanowire array on carbon cloth (NiCo2O4/CC) is proposed as a highly active electrocatalyst for ambient nitrate (NO3−) reduction to ammonia (NH3). In 0.1 m NaOH solution with 0.1 m NaNO3, such NiCo2O4/CC achieves a high Faradic efficiency of 99.0% and a large NH3 yield up to 973.2 µmol h−1 cm−2. The superior catalytic activity of NiCo2O4 comes from its half‐metal feature and optimized adsorption energy due to the existence of Ni in the crystal structure. A Zn‐NO3− battery with NiCo2O4/CC cathode also shows a record‐high battery performance.