Urea Electrosynthesis from Nitrate and CO 2 on Diatomic Alloys

Urea electrosynthesis from co‐electrolysis of NO3− and CO2 (UENC) provides an alternative route for realizing efficient and sustainable urea production. In this work, single‐atom Ru dispersed on Co (Ru1Co) is demonstrated as an effective and robust catalyst for the UENC. In situ spectroscopic measurements and theoretical simulations unravel the cooperative effect of Ru1 and Co sites to promote the UENC process via a tandem catalysis mechanism, where the Ru1 site activates the adsorption and hydrogenation of NO3− to form *NH2, while the Co site activates the adsorption and hydrogenation/deoxygenation of CO2 to form *CO. The generated *CO is then transferred from the Co site to the nearby Ru1 site which promotes the C─N coupling of *NH2 and *CO toward the urea formation. Strikingly, Ru1Co assembled in a flow cell shows the highest urea‐Faradaic efficiency of 50.1% with the corresponding urea yield rate of 22.34 mmol h−1 g−1 at −0.5 V (RHE), superior to most reported UENC catalysts for urea production.

Electrocatalytic Urea Production with Nitrate and CO₂ on a Ru‐Dispersed Co Catalyst

Wan,

Zhang,

Wang

et al. 2024

Research Progress of Dual‐Site Tandem Catalysts in the Preparation of Multi Carbon Products by Electro Reduction of CO₂

Xu,

Shang,

Guan

et al. 2024

The era of an energy economy driven by “carbon neutrality” is putting forward stricter requirements for the use of carbon resources and the governance of CO2. Electrochemical reduction of carbon dioxide reaction (CO2RR), driven by renewable energy, is a practical energy storage technology with broad application prospects. It can reduce CO2 into carbon‐based fuels and chemical products. Among them, multi‐carbon (C2+) products have higher energy density and larger market size, and can significantly reduce the global demand for fossil fuels and close the artificial carbon cycle. Introducing additional active sites into Cu‐based catalysts to prepare dual‐site tandem catalysts can regulate the electronic and geometric structure of the catalysts, break linear scale relationships, reduce reaction potential barriers, and bring superb and stable catalytic performance. Various types of dual‐site tandem catalysts are developed, and the understanding of the tandem effect is pushed to a higher level. This paper reviews several typical dual‐site tandem catalysts: atom–atom dual‐site tandem catalysts, atom‐particle dual‐site tandem catalysts, particle–particle dual‐site tandem catalysts, and heterogeneous interface dual‐site tandem catalysts. It then deeply analyzes the reaction mechanism and research progress of these advanced catalysts in CO2RR. In addition, the challenges and opportunities faced by such catalysts are also discussed.

Concurrently Selective Electrosynthesis of Ammonia and Glycolic Acid Over Cathodic Single‐Atom Cobalt and Anodic PdNi Alloying Catalysts

Zhang,

Li,

Zhang

et al. 2024

Herein, an electrocatalytic coupling system for selective ammonia and glycolic acid production over cathodic single‐atom Co (Co─N─C) and anodic PdNi alloying nanoparticles on the carbonized cellulose (PdNi/CBC), respectively are reported. As a cathodic electrocatalyst for nitrate reduction reaction (NtrRR), the Co─N─C displays remarkably high activity, delivering an NH3 yield rate of 20.5 ± 2.7 mg h−1 mgcat.−1 with a Faradaic efficiency (FE) of 95.5 ± 2.8% at −0.5 V (vs RHE). In situ spectroscopy combined with theoretical calculations unveiled the NtrRR mechanism on Co─N4 site. As an anodic electrocatalyst for ethylene glycol oxidation reaction (EGOR), the PdNi/CBC shows a high FE of 96.6 ± 1.7% for glycolic acid (GA) production at 1.6 V (vs RHE) and robust stability of 168 h. Remarkably, a proof of concept experiment of coupling electrocatalytic NtrRR with EGOR demonstrates that only an applied potential of −0.1 V (vs RHE) is required to reach a current density of 10 mA cm−2 for co‐producing ammonia and glycolic acid. As a result, the coupled NtrRR‐EGOR system can achieve an NH3 yield rate of 6.0 ± 0.6 mg h−1 mgcat.−1 and a GA yield rate of 16.8 ± 1.7 mg h−1 mgcat.−1 at −0.7 V (vs RHE).