Themed collection Nitrogen-cycle electrocatalysis

Xuping Sun, Jieshan Qiu and Chenghua Sun introduce this Inorganic Chemistry Frontiers themed collection on nitrogen cycle electrocatalysis.

In this review, we aim to systematically investigate the interaction of nitrogen species with iron sulfides and related materials, with the goal of understanding how abiotic processes may have contributed to the evolution of enzymes responsible for nitrogen transformations.

Ammonia (NH₃) is a crucial chemical commodity used extensively in fertilizer production and as a renewable potential energy carrier.

First-row transition metal-based electrocatalysts, including Cu, Fe, Co, Ni, and Ti-based electrocatalysts, for high-efficiency NO_x⁻ reduction are reviewed. These electrocatalysts should possess three advantages indicated in the figure above.

Electrochemical NO₃⁻-to-NH₃ conversion is an available option for sewage treatment and ammonia synthesis. This review summarized the theoretical insights, design strategy and challenges of Ti-based electrocatalysts for NO₃⁻-to-NH₃ conversion.

Photoelectrocatalytic NH₃ synthesis from N₂ and H₂O is a promising approach for N-neutralization goal based on catalytic strategies, such as vacancy engineering, ion doping, frustrated Lewis pair design, heterojunction construction, etc.

Nitrate (NO₃⁻) and nitrite (NO₂⁻) ions are common health-threatening contaminants in water. Thermal catalytic hydrogenation is a promising strategy to reduce nitrate and nitrite during water treatment.

This review summarizes recent advancements in catalysts for NH₃ electrosynthesis from NO₃⁻, highlights various strategies to regulate their apparent or intrinsic activities, and proposes the perspective and challenges in this emerging area.

This mini review chronicles the role of Ru(edta) (edta⁴⁻ = ethylenediaminetetraacetate) towards catalysing the electrochemical transformation of nitrogen cycle reactions, elucidating the complex mechanistic schemes.

An in-built bionic FeV cofactor in Fe-BiVO₄ catalyst decorated with 2D black phosphorus can not only adsorb and activate N₂ molecules, but also promote carrier separation and transfer, thus improving photocatalytic nitrogen reduction performance.

Nitrogen reduction reaction (NRR) is an essential process for ammonia synthesis. Synergetic effects, including the metal–metal and metal–ligands (non-metals) interactions, enhance the NRR performance.

Inert group-IVA elements can surprisingly enhance the e-N2RR capability of iron with an appropriate extent of alloying.

Fe/support catalysts exhibit excellent electrochemical NO₃RR performance owing to the strong metal–support interaction (SMSI) between Fe active sites and supports.

Core–shell Co₃O₄/NiFe LDH heterostructured nanosheets serve as remarkable NO₂⁻RR and OER bifunctional electrocatalysts for high-efficiency and low-cost ammonia production.

Using B-doped carbon dots loading to change the electron spin density of magnetic Co₃O₄ results in excellent activity in the electrocatalytic nitrate reduction reaction.

The high activity of the electrodeposited Ni/Ru hydroxide hybrid was attributed to the interaction between Ru and oxidized Ni species formed in the Ru–O–Ni matrix, which promoted the conversion of nitrate to ammonia through the synergistic effect.

Sb₂S₃ comprising atomically isolated and unsaturated Sb (Sb_AIU) sites is demonstrated as an efficient catalyst for NORR, attributed to the critical role of Sb_AIU sites in promoting NORR and inhibiting competitive hydrogen evolution.

β-PdBi₂ was proposed as a novel NORR catalyst for NH₃ synthesis with high efficiency and high selectivity, and its catalytic activity can be enhanced by a tensile strain.

A highly efficient approach for nitrate synthesis is developed under ambient conditions. The electrochemical generation of active chloride species by RuO₂@TiO₂/TP in chlorine evolution reaction effectively convert NO to nitrate in the electrolyte.

A rare-earth La-doped VS_2−x is reported as an effective catalyst for electrocatalytic nitrate-to-ammonia conversion, which is attributed to the synergy of La-dopants and S-vacancies to promote NO₃RR and suppress hydrogen evolution.

An Ag nanoparticle-decorated TiO₂ nanoribbon array on a titanium plate performs efficiently in electrocatalytic NO₂⁻ reduction to NH₃, achieving a large NH₃ yield of 8743.1 μg h⁻¹ cm⁻² with a high faradaic efficiency of 96.4%.