A simple synthesis of Co3O4@CNT to boost electrochemical nitrogen fixation

Oxygen vacancy modulation in interfacial engineering Fe3O4 over carbon nanofiber boosting ambient electrocatalytic N2 reduction

The oxygen vacancy modulation of interface-engineered Fe3O4 nanograins over carbon nanofiber (Fe@CNF) was achieved to improve electrocatalytic nitrogen reduction reaction (NRR) activity and stability via facile electrospinning and tuning thermal procedure. The optimal catalyst calcined at 800 ℃ (Fe@CNF-800) was endowed with abundant nanograin boundaries and optimized oxygen vacancy (Vo) concentration of iron oxides, thereby affording 37.1 μg h-1 mgcat.-1 (-0.2 V vs. reversible hydrogen electrode (RHE)) NH3 yield and rational Faraday efficiency (10.2%), with 13.6 times atomic activity enhancement compared to of that commercial Fe3O4. The interfacial effect of assembled nanograins in particles correlated with the formation of Vo and more intrinsic active sites, which is conducive to the trapping and activation of nitrogen (N2). The in-situ X-ray photoelectron spectroscopy (XPS) measurement revealed the real consumption of adsorbed oxygen when introducing N2 by the trapping effect of Vo. Density-Functional-Theory (DFT) calculation validates the promotive hydrogenation effect and elimination of hydrogen intermediate (H*) interacted with N2 transferring toward oxygen of the support. The optimal catalyst shows a lasting NRR activity at least 90 h, outperforming most reported Fe-based NRR catalysts.

FeMo–N nanosheet arrays supported on nickel foam for efficient electrocatalytic N2 reduction to NH3 under ambient conditions

The N content in the M–N bond is closely related to the catalytic activity and greatly improves the NRR performance.

Self-supported V-doped NiO electrocatalyst achieving a high ammonia yield of 30.55 μg h−1 cm−2 under ambient conditions

Vanadium doped nickel oxide grows on nickel foam exhibits a splendid NH3 yield and a high faradaic efficiency.

Nanomaterials for the electrochemical nitrogen reduction reaction under ambient conditions

As an important chemical product and carbon-free energy carrier, ammonia has a wide range of daily applications in several related fields. Although the industrial synthesis method using the Haber-Bosch process could meet production demands, its huge energy consumption and gas emission limit its long-time development. Therefore, the clean and sustainable electrocatalytic N2 reduction reaction (NRR) operating under conditions have attracted great attention in recent years. However, the chemical inertness of N2 molecules makes it difficult for this reaction to proceed. Therefore, rationally designed catalysts need to be introduced to activate N2 molecules. Here, we summarize the recent progress in low-dimensional nanocatalyst development, including the relationship between the structure and NRR performance from both the theoretical and experimental perspectives. Some insights into the development of NRR electrocatalysts from electronic control aspects are provided. In addition, the theoretical mechanisms, reaction pathways and credibility studies of the NRR are discussed. Some challenges and future prospects of the NRR are also pointed out.