Main-Group Sn Single Atoms on MoS for Selective Nitrite Electroreduction to Ammonia.

Electrocatalytic NO-to-NH reduction (NORR) offers an attractive way to remedy polluted NO and produce value-added NH. In this study, main-group Sn single atoms anchored on S-vacancy-rich MoS (Sn/MoS) are explored as a highly selective NORR catalyst. Combined theoretical computations and in situ spectroscopic measurements reveal that the isolated Sn sites of Sn/MoS can not only promote NO-to-NH activation and hydrogenation but also favor NH desorption and restrict H adsorption, thus enabling a highly selective NORR for NH synthesis.

Selective urea electrosynthesis nitrate and CO reduction on uncoordinated Zn nanosheets.

Electroreduction of NO and CO to urea (ENCU) represents a fascinating strategy to enable waste NO/CO removal and sustainable urea production. Herein, uncoordinated Zn nanosheets (U-Zn) are developed as a highly selective ENCU catalyst, exhibiting the highest urea-faradaic efficiency of 31.8% with the corresponding urea yield rate of 39.

Electroreduction of CO and nitrate for urea synthesis on a low-coordinated copper catalyst.

Electroreduction of CO and NO to urea (ECNU) offers a fascinating route for migrating NO pollutants and synthesizing valuable urea. Herein, low-coordinated copper (L-Cu) is developed as an effective ECNU catalyst, delivering the highest urea yield rate of 30.96 mmol h g and urea-faradaic efficiency of 50.

Efficient urea electrosynthesis from nitrite and CO reduction on single W atom catalyst.

Electroreduction of CO and NO to urea (ECNU) provides a fascinating method for concurrently migrating polluted NO and producing value-added urea. In this study, atomically dispersed W on MoS (W/MoS) is designed as an efficient ECNU catalyst, which exhibits the highest Faraday efficiency of 60.11 % and urea yield rate of 35.

Efficient urea electrosynthesis from CO and nitrate on amorphous TiS.

Electrosynthesis of urea via co-electrolysis of CO and NO (EUCN) offers a promising avenue for simultaneously addressing environmental concerns and producing valuable urea. In this study, we report that amorphous TiS (a-TiS) with rich S-vacancies (S) serves as an effective and robust EUCN catalyst. In a flow electrolyzer, a-TiS achieves the maximum urea-Faradaic efficiency of 34.

Porphyrin-Confined Supported Ultrasmall Ir Clusters as Oxygen Evolution Catalysts for Water Electrolysis.

Metalloporphyrin ligands themselves can participate in the redox process, making them beneficial in promoting the multielectron catalytic process of the oxygen evolution reaction (OER). However, OER catalysts synthesized by traditional chemical strategies face challenges in water electrolysis. We synthesized high-performance and stable alkaline and acidic OER electrocatalysts loaded with ultrasmall iridium clusters by taking advantage of the attraction and confinement of Ir atoms by the Ir-N bonds formed by the porphyrin cavity.

Relay Catalysis of Isolated Rhodium-Alloyed Copper Boosts Urea Electrosynthesis from Nitrate and CO.

Urea electrosynthesis from the coelectrolysis of NO and CO (UENC) presents a fascinating approach for simultaneously migrating NO pollutants and producing valuable urea. In this study, isolated Rh-alloyed copper (RhCu) is explored as a highly active and selective catalyst toward the UENC. Combined in situ spectroscopic analysis and theoretical calculations reveal the relay catalysis of the Rh site and Cu site to promote the UENC energetics, in which the Rh site activates NO to form *NH while the Cu site activates CO to form *CO.

Boosting Electroreduction of Nitrate and CO to Urea on a Tandem Fe/MoS Catalyst.

Urea electrosynthesis by coelectrolysis of NO and CO (UENC) holds enormous promise for sustainable urea production, while the efficient UENC process relies on the rational design of high-performance catalysts to facilitate the electrocatalytic C-N coupling efficiency and the hydrogenation reaction process. Herein, Fe single atoms supported on MoS (Fe/MoS) are developed as a highly effective and robust catalyst for UENC. Theoretical calculations and operando spectroscopic measurements reveal a tandem catalysis mechanism of the Fe-S motif and MoS-edge to jointly promote the UENC process, where the Fe-S motif drives the early C-N coupling and subsequent *CONO-to-*CONH step.

Construction of dual sites on FeS surface for enhanced electrocatalytic reduction of nitrite to ammonia.

Cost-effective iron sulfides (FeS) hold great potential as high-performance catalysts for NO electroreduction to NH (NOER), which is hindered by the weak NO activation. Herein, the design of nonmetal-doped FeS electrocatalysts was initially conducted by density functional theory (DFT) computations. We found that doping with different nonmetal atoms effectively not only regulates the electronic structures of the d-electrons of Fe atoms but also creates the unique p-d hybridized dual active sites, thereby boosting the efficient NO activation.

Atomically Dispersed Cu on InO for Relay Electrocatalytic Conversion of Nitrate and CO to Urea.

Urea electrosynthesis from coelectrolysis of NO and CO (UENC) holds a significant prospect to achieve efficient and sustainable urea production. Herein, atomically dispersed Cu on InO (Cu/InO) is designed as an effective and robust catalyst for the UENC. Combined theoretical calculations and in situ spectroscopic analysis reveal the synergistic effect of the Cu-O-In site and the In site to boost the UENC energetics via a relay catalysis pathway, where the Cu-O-In site drives *NO → *NH and the In site catalyzes *CO → *CO.

Single-Atom Rh Alloyed Co for Urea Electrosynthesis from CO and NO.

Single-atom Rh alloyed Co (RhCo) is explored as an efficient catalyst for urea electrosynthesis via coelectrolysis of CO and NO (UECN). Theoretical calculations and in situ spectroscopic measurements unravel the synergetic effect of Co and Rh in promoting the UECN process, where the Rh site activates NO to form *NH, while the Co site activates CO to form *CO. The formed *CO then desorbs from the Co site and transfers to the Rh site, followed by continuous C-N coupling with *NH formed on the Rh site to synthesize urea.

Direct Eight-Electron NO Electroreduction to NH Enabled by an Fe Double-Atom Catalyst.

NO is a dominant atmosphere pollutant, causing ozone depletion and global warming. Currently, electrochemical reduction of NO has gained increasing attention to remove NO, but its product is worthless N. Here, we propose a direct eight-electron (8) pathway to electrochemically convert NO into NH.

Urea Electrosynthesis from Nitrate and CO on Diatomic Alloys.

Urea electrosynthesis from co-electrolysis of NO and CO (UENC) offers a promising technology for achieving sustainable and efficient urea production. Herein, a diatomic alloy catalyst (CuPdRh-DAA), with mutually isolated Pd and Rh atoms alloyed on Cu substrate, is theoretically designed and experimentally confirmed to be a highly active and selective UENC catalyst. Combining theoretical computations and operando spectroscopic characterizations reveals the synergistic effect of Pd-Cu and Rh-Cu active sites to promote the UENC via a tandem catalysis mechanism, where Pd-Cu site triggers the early C-N coupling and promotes *CONO-to-*CONH steps, while Rh-Cu site facilitates the subsequent protonation step of *CONH to *COOHNH toward the urea formation.

P-Block Antimony-Copper Single-Atom Alloys for Selective Nitrite Electroreduction to Ammonia.

Electrocatalytic reduction of NO to NH (NORR) offers an effective method for alleviating NO pollution and generating valuable NH. Herein, a p-block single-atom alloy, namely, isolated Sb alloyed in a Cu substrate (SbCu), is explored as a durable and high-current-density NORR catalyst. As revealed by the theoretical calculations and operando spectroscopic measurements, we demonstrate that Sb incorporation can not only hamper the competing hydrogen evolution reaction but also optimize the d-band center of SbCu and intermediate adsorption energies to boost the protonation energetics of NO-to-NH conversion.

Excellent thermomagnetic power generation for harvesting waste heat a second-order ferromagnetic transition.

Thermomagnetic generation (TMG), a promising technology to convert low-grade waste heat to electricity, utilizes high performance TMG materials. However, the drawbacks of large hysteresis, poor mechanical properties and inadequate service life hinder the practical applications. For the first time, we evaluated the effect of different phase transitions on the TMG performance by systematically comparing the TMG performance of three typical Heusler alloys with similar composition but different phase transitions.

Electrocatalytic reduction of nitrite to ammonia on undercoordinated Cu.

Electrocatalytic NO-to-NH reduction (NORR) has emerged as an intriguing route for simultaneous mitigation of harmful nitrites and production of valuable NH. Herein, we design for the first time undercoordinated Cu nanowires (u-Cu) as an efficient and selective NORR electrocatalyst, delivering the maximum NO-to-NH faradaic efficiency of 94.7% and an ammonia production rate of 494.

Dendritic-like MXene quantum dots@CuNi as an efficient peroxidase candidate for colorimetric determination of glyphosate.

Oxidized MXene quantum dots@CuNi bimetal (MQDs@CuNi) were firstly prepared through a simple hydrothermal method. Compared to the controlled samples, MQDs@CuNi showed the highest peroxidase-like activity. The catalytic mechanism of MQDs@CuNi was investigated using a steady-state fluorescence analysis, which showed that MQDs@CuNi efficiently decomposes HO and produces highly reactive hydroxyl radicals (OH).

PdCu Single-Atom Alloys for High-Current-Density and Durable NO-to-NH Electroreduction.

Electrochemical reduction of NO to NH (NORR) offers a prospective method for efficient NH electrosynthesis. Herein, we first design single-atom Pd-alloyed Cu (PdCu) as an efficient and robust NORR catalyst at industrial-level current densities (>0.2 A cm).

Electrocatalytic nitrite reduction to ammonia on an Rh single-atom catalyst.

Electrocatalytic NO reduction to NH (NORR) holds great promise as a green method for high-efficiency NH production. Herein, an Rh single-atom catalyst where isolated Rh supported on defective BN nanosheets (Rh/BN) is reported to exhibit the exceptional NORR activity and selectivity. Extensive experimental and theoretical studies unveil that the high NORR performance of Rh/BN arises from the single-atom Rh sites, which not only promote the activation and hydrogenation of NO-to-NH process, but also hamper the undesired hydrogen evolution.

Promoting Nitrite-to-Ammonia Electroreduction over Amorphous CoS Nanorods.

Electrocatalytic nitrite reduction to ammonia (NORR) emerges as a promising route to simultaneously attain harmful NO removal and green NH synthesis. In this study, amorphous CoS nanorods (a-CoS) are first demonstrated as an effective NORR catalyst, which exhibits the maximum FE of 88.7% and NH yield rate of 438.

Electrochemical reduction of nitrite to ammonia on amorphous MoO nanosheets.

Electrocatalytic NO reduction to NH (NORR) is an appealing approach for mitigating NO pollution and for the synthesis of valuable NH, and so the exploration for high-performance NORR catalysts is pivotal yet remains challenging. Herein, amorphous MoO nanosheets (am-MoO) were designed as a high-performance NORR electrocatalyst, delivering a maximum NO-to-NH faradaic efficiency of 94.8% and NH yield rate of 480.

An Amorphization-Engineered Catalyst for Electrocatalytic Reduction of Nitric Oxide to Ammonia.

Electrocatalytic NO-to-NH conversion (NORR) provides a fascinating route toward the eco-friendly and valuable production of NH. In this study, amorphous FeS (a-FeS) is first demonstrated as a high-efficiency catalyst for the NORR, showing a maximum FE of 92.5% with a corresponding NH yield rate of 227.

Single-atom Cu anchored on MoC boosts nitrite electroreduction to ammonia.

We design single-atom Cu anchored on MoC (Cu/MoC) as an effective electrocatalyst towards electrochemical nitrite reduction to ammonia (NORR), exhibiting an NH-faradaic efficiency of 91.5% with a corresponding NH yield rate of 472.9 μmol h cm at -0.

Ampere-Level Nitrate Electroreduction to Ammonia over Monodispersed Bi-Doped FeS.

Electrochemical conversion of NO into NH (NORR) holds an enormous prospect to simultaneously yield valuable NH and alleviate NO pollution. Herein, we report monodispersed Bi-doped FeS (Bi-FeS) as a highly effective NORR catalyst. Atomic coordination characterizations of Bi-FeS disclose that the isolated Bi dopant coordinates with its adjacent Fe atom to create the unconventional p-d hybridized Bi-Fe dinuclear sites.

Nb-doped NiO nanoflowers for nitrite electroreduction to ammonia.

Electrocatalytic reduction of nitrite to ammonia (NORR) is considered as an appealing route to simultaneously achieve sustainable ammonia production and abate hazardous nitrite pollution. Herein, atomically Nb-doped NiO nanoflowers are designed as a high-performance NORR catalyst, which exhibits the highest NH-Faradaic efficiency of 92.4% with an NH yield rate of 200.