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Plasmon-induced photocatalysis showed great potential to improve the photocatalytic nitrogen fixation efficiency, due to the localized surface plasmon resonance effect. The performances of the photocatalytic nitrogen fixation were evaluated by ammonia production rate, apparent quantum efficiency, solar-to-ammonia efficiency, and turnover frequency. The ammonia production rate was compared with three kinds of catalyst, i.e. nano-metals, nano-metal modified semiconductors and highly doped semiconductors. The outstanding contributions of hot electron injection effect, near-field enhancement effect, photothermal effect to nitrogen fixation efficiency were described. The creation of active sites, construct vacancies, and doping regulation were effective methods to prepare high performance catalysts for photocatalytic nitrogen fixation. • Nano-metal-modified semiconductor catalysts achieve ammonia production rate of 785 μmol g−1 h−1. • Highiy doped semiconductors re-define the landscape of photocatalytic NH 3 generation. • The ammonia production rate, apparent quantum efficiency and Solar-to-Ammonia can be used to evaluate the performance ofphotocatalyst. • Hot electron injection effect as a guide for the synthesis of plasma-induced photocatalysts. [ABSTRACT FROM AUTHOR]

Photocatalytic nitrogen reduction presents a promising technology for environmentally friendly ammonia synthesis under mild conditions. However, the performance of photocatalysts is often hindered by high charge carrier recombination and insufficient adsorption and activation of nitrogen molecules. A novel Bi 12 O 17 Cl 2 /BiOCOOH/Bi 2 MoO 6 heterojunction photocatalyst was successful synthesis through surface ion-exchange technique by potassium chloride. The introduction of Bi-rich Bi 12 O 17 Cl 2 on BiOCOOH/Bi 2 MoO 6 heterojunction not only improves electron transfer efficiency due to the dual type-II heterojunction effect but also facilitates on-site N 2 adsorption and activation for solar ammonia production by promoting oxygen vacancies. The high photocatalytic nitrogen fixation activity of the Bi 12 O 17 Cl 2 /BiOCOOH/Bi 2 MoO 6 was 107.78 μmol g−1 h−1 without any sacrificial agent. DFT calculations indicate that oxygen vacancies serve as the active site for adsorbed N 2 , the hydrogenation process preferentially forms on the distal N 2 atom with a lower activation energy about 0.6 eV. Therefore, the combination of oxygen vacancies and band engineering accelerates the production of ammonia. This endeavor holds the potential to unleash the capabilities of engineering for Bi-rich heterojunctions materials with oxygen vacancies, thereby achieving high-efficiency solar-driven N 2 -to-NH 3 conversion in aqueous environments. [Display omitted] • A novel Bi 12 O 17 Cl 2 /BiOCOOH/Bi 2 MoO 6 heterojunction photocatalyst through surface ion-exchange technique by potassium chloride. • The high photocatalytic nitrogen fixation activity of the Bi 12 O 17 Cl 2 /BiOCOOH/Bi 2 MoO 6 was 107.78 μmol g−1 h−1 without any sacrificial agent. • The built-in double type-II heterojunction promotes the on-site N 2 adsorption and activation of vacancy oxygen. [ABSTRACT FROM AUTHOR]

• High volume precipitation does not translate into increased moss-associated nitrogen (N) fixation rates. • N fixation increased more in a tropical moss compared to a subarctic moss under all rainfall regimes. • Less than 1 % of fixed N was leached from mosses within a 1-month period. • N leaching from mosses was more sensitive to watering volume than frequency. Nitrogen (N) fixation by moss-cyanobacteria associations has been recognized as an important N input pathway in many ecosystems from arctic tundra to tropical forests. However, the transfer of fixed N 2 from mosses to the soil as well as the effects of rainfall frequency and volume on this N transfer has hardly been studied – even though mosses can leach nutrients upon rewetting. In this study, we investigated the transfer of fixed N 2 by moss-cyanobacteria associations in one month under four watering regimes with a combination of high and low volume and frequency. For this, we used two morphologically similar moss species collected from ecosystems with different climate and N availability (subarctic - Hylocomium splendens ; and tropical - Thuidium delicatulum). Acetylene reduction assays were conducted as a measure of N 2 fixation rates in mosses, and 15N-N 2 tracing was used to follow the fixed N 2 from moss to the underlying substrate. Nitrogen fixation rates were higher in T. delicatulum than in H. splendens , but rainfall volume and frequency did not show strong effects on N 2 fixation rates. Nonetheless, the extent of N leached from mosses was more sensitive to an increase in rainfall volume than to an increase in frequency, and more N was lost from T. delicatulum under high volume precipitation than from H. splendens. Both total nitrogen and 15N enrichment results demonstrate that the fixed N 2 was mostly stored in moss tissues with less than 1 % leached to the substrate. Our results show that both moss species retain almost all fixed N 2 within their tissues under small rainfall disturbances within one month, while increased N availability under higher precipitation volume renders some moss species an important N source for the soil. [Display omitted] [ABSTRACT FROM AUTHOR]

In the present paper, polyaniline modification of Mn 0.5 Cd 0.5 S composite (PANI/MCS) was fabricated by a simple electrostatic adsorption method. The introduction of PANI makes PANI/MCS composites have better visible light absorption and higher photogenerated carrier segregation efficiency, thus showing better photocatalytic performance. The results show that the 50-PANI/MCS photocatalyst has the best hydrogen production capacity, which was 2.2 times greater than neat MCS. Meanwhile, the nitrogen fixation performance of the best sample 50-PANI/MCS was 4.93 times that of pure MCS. After that, a reasonable reaction mechanism was obtained through various characterization data. A cheap and readily available composite photocatalyst has been synthesized. This paper has good reference value in the area of development of efficient composite photocatalyst. In this paper, polyaniline modified Mn 0.5 Cd 0.5 S composite (PANI/MCS) was prepared by simple electrostatic adsorption. The introduction of PANI makes PANI/MCS composites have better visible light absorption capacity and higher photogenerated carrier separation efficiency, thus showing better photocatalytic performance. The results show that the 50-PANI/MCS photocatalyst has the best hydrogen production capacity, which is 2.2 times that of pure MCS. At the same time, the nitrogen fixation performance of the best sample 50-PANI/MCS was 4.93 times that of pure MCS. A cheap and readily available composite photocatalyst has been synthesized. [Display omitted] • A new method for the modification of Mn x Cd 1-x S by conductive polymer was proposed. • The whole prepared process of PANI/MCS composite material is cheap and simple. • PANI/MCS exhibits accelerated photogenerated carrier separation. • PANI/MCS exhibits better hydrogen evolution and nitrogen fixation performance. [ABSTRACT FROM AUTHOR]

• Sb(III) and Sb(V) fates coupled jarosite formation by A. ferrooxidans were studied. • Sb(III) inhibited the growth of A. ferrooxidans and the formation of jarosite. • Sb(III) formed Sb-O complex with ferrous minerals in a lower crystallization. • Sb(V) is adsorbed on the surface of the mineral as a hydrolyzed substance. • Differential effects of Sb(III) and Sb(V) on bacterial metabolism were revealed. Secondary iron-sulfate minerals such as jarosite, which are easily formed in acid mine drainage, play an important role in controlling metal mobility. In this work, the typical iron-oxidizing bacterium Acidithiobacillus ferrooxidans ATCC 23270 was selected to synthesize jarosite in the presence of antimony ions, during which the solution behavior, synthetic product composition, and bacterial metabolism were studied. The results show that in the presence of Sb(V), Fe2+ was rapidly oxidized to Fe3+ by A. ferrooxidans and Sb(V) had no obvious effect on the biooxidation of Fe2+ under the current experimental conditions. The presence of Sb(III) inhibited bacterial growth and Fe2+ oxidation. For the group with Sb(III), products with amorphous phases were formed 72 hr later, which were mainly ferrous sulfate and pentavalent antimony oxide, and the amorphous precursor was finally transformed into a more stable crystal phase. For the group with Sb(V), the morphology and structure of jarosite were changed in comparison with those without Sb. The biomineralization process was accompanied by the removal of 94% Sb(V) to form jarosite containing the Fe-Sb-O complex. Comparative transcriptome analysis shows differential effects of Sb(III) and Sb(V) on bacterial metabolism. The expression levels of functional genes related to cell components were much more downregulated for the group with Sb(III) but much more regulated for that with Sb(V). Notably, cytochrome c and nitrogen fixation-relevant genes for the A.f _Fe2+_Sb(III) group were enhanced significantly, indicating their role in Sb(III) resistance. This study is of great value for the development of antimony pollution control and remediation technology. Diagram of the mechanism of ferrous oxidation by A. ferrooxidans coupled with antimony conversion. The abbreviation of A. f in the figure represents A. ferrooxidans. [Display omitted] [ABSTRACT FROM AUTHOR]

Despite the importance of alkaline seafloor hydrothermal vents in broadening our understanding of deep-sea hydrothermal ecosystems, little is known about the mobility and concentrations of micronutrient transition metals in these environments. Here, we present new analyses of micronutrient transition metal concentrations in vent fluids from the iconic Lost City Hydrothermal Field (LCHF) and report concentrations of Fe = 2.9–18.3 µmol/kg, Zn = 1.30–5.86 µmol/kg, Cu = 0.43–5.06 µmol/kg, Ni = 86.4–556 nmol/kg, Mn = 8.3–274 nmol/kg, V = 25.9–127 nmol/kg, Mo = 24–94 nmol/kg, Co = 8.0–135 nmol/kg, W = 4.8–16 nmol/kg, and Cd = 1.7–4.5 nmol/kg. We additionally present results of a hydrothermal lherzolite alteration experiment conducted at 300 °C, 500 bar. Transition metal concentrations and major chemical parameters of experimental reaction fluids are broadly similar to LCHF vent fluids, indicating that transition metal concentrations in LCHF vent fluids, and alkaline hydrothermal fluids more generally, reflect metal solubility controlled by underlying rock-buffered hydrothermal reactions. Concentrations of Ni and Mo are especially noteworthy because of their recognized importance for biological methanogenesis (Ni) and nitrogen fixation (Mo). When compared with known biological thresholds, our findings indicate that Ni concentrations in LCHF vent fluids are sufficient to support the robust methane-metabolizing microbial communities observed in the immediate vicinity of LCHF vents and suggest that Ni availability influences the spatial distribution of LCHF methanogens. Furthermore, our laboratory hydrothermal experiments demonstrate that Mo concentrations of similar magnitude to those observed in LCHF vent fluids (and also modern seawater) can be obtained by hydrothermal alteration of ultramafic rocks with Mo-free (Na, Ca) Cl aqueous solution. Thus, we conclude that alkaline hydrothermal fluids were likely similarly enriched in Mo prior to oxidation of the Earth's atmosphere and ocean, providing localized Mo-rich geochemical environments capable of supporting Mo-dependent nitrogen fixation at currently recognized threshold concentrations. [ABSTRACT FROM AUTHOR]

Nitrogenase, the key enzyme for biological nitrogen fixation, is an evolutionary singularity, as only one mechanism capable of catalyzing the reduction of atmospheric N 2 into fixed nitrogen is known to have evolved. Nitrogenase has three metal isoforms (iron, molybdenum, and vanadium) and is thus connected and dependent upon biogeochemical cycles for metal availability. Molybdenum is abundant in modern oceans, was very scarce in ancient oceans and remains scarce in modern terrestrial environments. Despite its scarcity, it is proposed that early nitrogenases first utilized Mo-cofactors given its catalytic advantages over abundant Fe. To understand the evolution and diversification of the nitrogen cycle, we must first understand the paleoecological and planetary conditions that give rise to biological nitrogen fixation. The evolution of nitrogen fixation undoubtedly altered nearly all corners of the biosphere, given the essential role of nitrogen in the synthesis of biomass. To date, there is no unified view on what planetary conditions gave rise to nitrogen fixation or how these conditions have sustained it evolutionarily. Intriguingly, the concentrations of metals that nitrogenases require to function have changed throughout Earth's history. In this review, we describe the interconnection of the metal and nitrogen cycles with nitrogenase evolution and the importance of ancient ecology in the formation of the modern nitrogen cycle. We argue that exploration of the nitrogen cycle's deep past will provide insights into humanity's immediate environmental challenges centered on nitrogen availability. [ABSTRACT FROM AUTHOR]

The availability of nutrients such as nitrogen (N) affects crop productivity. Unfortunately, the intensive use of synthetic N fertilizers has detrimental economic and environmental consequences. Engineered associative diazotrophs hold immense potential to help many crops acquire N from the air via biological N fixation. The mechanistic understanding of plant–diazotroph interactions forms the basis of engineering these associations to increase the transfer of fixed N to the plants. Biorthogonal signaling is a promising approach to engineering specific, efficient, ecofriendly plant–diazotroph interactions. The composition of root exudates, the physical proximity of diazotrophs to the plants, their nontoxic nature, their efficiency in fixing N, and their amenability to genetic manipulations are essential for engineering associations between diazotrophs and crops for sustainable agriculture. Diazotrophs are bacteria and archaea that can reduce atmospheric dinitrogen (N 2) into ammonium. Plant–diazotroph interactions have been explored for over a century as a nitrogen (N) source for crops to improve agricultural productivity and sustainability. This scientific quest has generated much information about the molecular mechanisms underlying the function, assembly, and regulation of nitrogenase, ammonium assimilation, and plant–diazotroph interactions. This review presents various approaches to manipulating N fixation activity, ammonium release by diazotrophs, and plant–diazotroph interactions. We discuss the research avenues explored in this area, propose potential future routes, emphasizing engineering at the metabolic level via biorthogonal signaling, and conclude by highlighting the importance of biocontrol measures and public acceptance. [ABSTRACT FROM AUTHOR]

Although commonly cited to be out of balance, the N cycle is balanced over long time scales and is likely not currently significantly out of balance within the errors of our geochemical estimates or biological extrapolations. Habitats for N 2 fixation have recently been discovered (polar regions and deep sea) or proposed (oxygen-depleted zones, ODZs), although their significance remains unresolved. There are currently significant issues for measuring the basic characteristics of marine N 2 fixation ranging from determination of in situ rates to identification and quantification of species. There continue to be discoveries of new diazotrophs, although their significance and relative contributions remain to be resolved, from haptophyte and diatom symbionts to non-cyanobacterial diazotrophs. N 2 fixation in Trichodesmium continues to be incompletely understood, with implications for cell biology and N 2 fixation in plants. Biological nitrogen (N 2) fixation is critical in global biogeochemical cycles and in sustaining the productivity of the oceans. There remain many unanswered questions, unresolved hypotheses, and unchallenged paradigms. The fundamental balance of N input and losses has not been fully resolved. One of the major N 2 -fixers, Trichodesmium , remains an enigma with intriguing biological and ecological secrets. Cyanobacterial N 2 fixation, once thought to be primarily due to free-living cyanobacteria, now also appears to be dependent on microbial interactions, from microbiomes to unicellular symbioses, which remain poorly characterized. Nitrogenase genes associated with diverse non-cyanobacterial diazotrophs (NCDs) are prevalent, but their significance remains a huge knowledge gap. Answering questions, new and old, such as those discussed here, is needed to understand the ocean's N and C cycles and their responses to environmental change. [ABSTRACT FROM AUTHOR]

The conventional ammonia production process using the Haber-Bosch (H-B) method is highly efficient but necessitates severe reaction conditions with a large energy consumption. Meanwhile, a significant CO 2 emission are generated due to the acquisition of H 2. This study proposed a system combined the non-thermal plasma and fluidized catalysts with the water vapor as the green feedstock for high-efficiency ammonia synthesis. Results reveal that bimetallic Co-Ni supported catalysts on the MgO carrier exhibit notably higher NH 3 formation rates than single-component metal-supported catalysts and no catalysts. The highest NH 3 formation rate, achieved with a 4 wt% catalysts loading, reached 12.07 μmol g−1h−1 (specific energy input of 2.15 kJ L−1, energy efficiency of 6.57 mg kW−1h−1). A synergistic effect between the fluidized catalysts and the plasma was observed. It greatly improves ammonia yield and provides a new platform for sustainable ammonia synthesis. [Display omitted] • A plasma-coupled fluidized catalysts for ammonia synthesis is proposed. • The synergistic effect of DBD plasma and fluidized catalysts is explored in depth. • The green ammonia synthesis process is based on N 2 and H 2 O as feedstock. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effects of organic amendments on saline-alkali soil improvement were compared. • The optimal blending ratio of organic amendments was 20%. • High-temperature pretreatment compost favored soil improvement and plant growth. • High-temperature pretreatment composting improved plant antioxidant capacity. • Plant growth was improved by altering soil-dominant microflora and composition. Short-term high-temperature pretreatment can effectively shorten the maturity period of organic waste composting and improve the fertilizer efficiency and humification degree of products. To investigate the effect and mechanism of the end products on the saline–alkali soil improvement and plant growth, the short-term high-temperature pretreatment composting (SHC) and traditional composting (STC) were separately blended with saline–alkali soil in a ratio of 0–40 % to establish a soil–fertilizer blended matrix for cultivating Lolium perenne L. The pot experiments combined with principal component analysis showed Lolium perenne L. planted in 20 % SHC-blended saline–alkali soil had the best growth effect, and its biomass, chlorophyll content, and plant height were 109–113 % higher than STC. The soil physicochemical property analysis showed that SHC and STC increased the soil nutrient content, humification degree, and enzyme activity at any blending ratio. The microbial analysis showed that 20 % SHC in the saline–alkali soil stimulated the growth of functional microorganisms and the addition of SHC promoted the sulfur cycle, nitrogen fixation, and carbon metabolism in the soil–plant system. The correlation analysis showed that pH; nutrient contents; and urease, catalase, sucrase, and phosphatase activities in the saline–alkali soil were significantly correlated with plant growth indexes (p < 0.05). Georgenia and norank_f__Fodinicurvataceae had a stronger correlation with four types of enzyme activities (p < 0.01). SHC improved the saline–alkali soil and promoted plant growth by adjusting soil pH, increasing soil nutrients, and influencing soil enzyme activity and dominant flora. This study provides a theoretical basis for applying SHC products in soil improvement. [ABSTRACT FROM AUTHOR]

In this paper, the nano silicon carbide with different sizes was prepared without hydrofluoric acid by using simple milling and related low temperature etching process in normal pressure. Also, it was the first time verified that 3-C dominated crystalline form of polycrystalline silicon carbide is etched, leaving the 6-H silicon carbide crystalline form by the Raman spectra and HAADF-STEM (high-angle-annular dark-field scanning transmission electron microscopy) imaging that. The application of the alkali etching technique could precise control the partial structural transformation of silicon carbide crystals to a certain extent, which further expands the traditional crystal structure transformation process. In addition, this paper demonstrates the silicon carbide composites in photocatalytic removal of various organic pollutants from aqueous solutions. In the photo degradation of MB (Methylene Blue), the removal rate of the modified silicon carbide shown ten times as much as the commercial silicon carbide. The 1-h degradation efficiency was significantly higher in the 50 μL H 2 O 2 system (100.0%, 86.8% and 89.9% removal of MB, Rhodamine B, Methyl Orange and Tetracycline hydrochloride, respectively). Furthermore, the unit spin concentrations of vacancy defects, superoxide radicals and hydroxyl radicals were quantitatively analyzed. The vacancy defects of the etched material were 1000 times higher than before, and the modified silicon carbide had higher transmittance to infrared and visible light. It strongly absorbs ultraviolet light. Conversely, the research on micron-sized silicon carbide loaded with Ag and Pt atoms found that it had a nitrogen fixation effect during the warming up process, in a nitrogen atmosphere. [ABSTRACT FROM AUTHOR]

A series of isostructural Co/Ni-MOFs with different linearly bridged bipyridines as organic linkers has been designed and synthesized. Experimental studies reveal that linker engineering by tuning the functional block of the pyridine-bridging units renders these MOFs derived materials with significantly improved electrocatalytic nitrogen reduction reactions (eNRR) to NH 3. Among them, at −0.4 V vs reversible hydrogen electrode the one containing a 1,3,4-thiadiazole unit exhibits the best eNRR performance in 0.1 M Na 2 SO 4 with the highest NH 3 yield (39.7 μg h−1 mg−1) and Faraday efficiency (33.3 %). This excellent nitrogen fixation performance comes from the synergistic effect of the heterojunction formed by the Co 2 N component that is conducive to nitrogen fixation and the Co 9 S 8 component that inhibits hydrogen evolution in the derived material. Significantly, the systematic tuning of the bridging ligands in MOFs provides a new pathway to develop eNRR electrocatalysts. By tuning the functional block of the pyridine-bridging units renders these MOFs derived materials with significantly improved electrocatalytic nitrogen reduction reactions to NH 3. [Display omitted] • Six isostructural Co/Ni-MOFs with different ligands were designed and synthesized. • Tuning the functional block of catalysts improves nitrogen fixation property. • The Co-dpt-hfipbb-800 catalyst exhibits the highest NH 3 yield of 39.7 μg h−1 mg−1. • The synergistic effect of the heterojunction is conducive to nitrogen fixation. [ABSTRACT FROM AUTHOR]

It is believed that nitrogen-fixing eukaryotes do not exist in nature, and constructing such eukaryotes is extremely challenging. Coale et al. , however, have identified the first eukaryote capable of fixing nitrogen through a nitroplast organelle. Understanding the eukaryotic nitrogen-fixing machinery may advance the development of artificial nitrogen-fixing crops and industrial yeasts. [ABSTRACT FROM AUTHOR]

A novel photocatalyst WO 3 /BiMOF/Bi 2 WO 6 was prepared by self-assembly of benzene dicarboxylic acid ligand (H 2 BDC) anchoring Bi source on the surface of Bi 2 WO 6 to form BiMOF, in which WO 3 spherical particles were scattered uniformly. Thereby, an amount of metal and oxygen vacancies (V M + O) are generated. The 3D flower-like spherical photocatalyst has a large specific surface area and close interfacial contacts, which can provide sufficient channels for carrier migration. The introduction of BiMOF enhanced the light absorption capability of photocatalyst. As a result, the flower-like WO 3 /BiMOF/Bi 2 WO 6 structure exhibits excellent nitrogen fixation as well as high-level photocatalytic activity in degrading Rhodamine B (RhB) and tetracycline (TC) under visible light. For one thing, WO 3 /BiMOF/Bi 2 WO 6 produce ammonia up to 227 μmol L−1 h−1. For another, the degradation efficacy displayed by RhB 99.3% in 15 min and TC 93.6% degradation in 50 min, respectively. In addition, the catalysts showed excellent cyclic stability, with constant degradation efficiencies for at least 4 cycles. The experimental results of free radical scavenging showed that holes (h+) and superoxide radical (·O2−) were the main active substances in the photodegradation process. Therefore, the photocatalytic mechanism of 3D flower-like WO 3 /BiMOF/Bi 2 WO 6 was also proposed. [Display omitted] • Design of a novel Bi-source MOF to load WO 3 as a heterojunction on a 3D hydrangea BiMOF. • Photocatalytic synthesis of ammonia, degradation of tetracycline (TC), rhodamine B (RhB). • Improved ammonia production and tetracycline(TC) and dye(RhB) degradation efficiencqy. • The photocatalytic mechanism of ammonia synthesis and degradation reaction was elaborated. [ABSTRACT FROM AUTHOR]

The simultaneous degradation of organic pollutants and generation of value-added compounds like ammonia and hydrogen energy has recently gained considerable attention in photocatalysis. The present study deals with successful preparation of novel AgVO 3 nanowire@rGO-tetrahedral Ag 3 PO 4 (110) (AGA) heterojunction and utilized for enhanced generation of NH 3 and H 2 from N-containing antibiotic sulfamethoxazole (SMX) under visible light. The prepared catalyst was well characterized by XRD, SEM, TEM and XPS to confirm the formation of heterojunction. The results indicated that the composite exhibited 546.0 μmol g−1 of hydrogen evolution rate, which is approximately 3.6 (153.6 μmol g−1) and 5.1 (108.7 μmol g−1) times higher than the pure AgVO 3 and Ag 3 PO 4 respectively after 6 h. Similarly, 38.3 mg L−1g−1 of NH 3 generation was observed during 6 h of SMX degradation, which is about 1.9 and 2.8 times higher than the pure AgVO 3 (20.1 mg L−1g−1) and Ag 3 PO 4 (13.7 mg L−1g−1) respectively. The formation of heterojunction between AgVO 3 and Ag 3 PO 4 not only promotes the transfer of electron but also prevents the recombination which eventually enhances the catalytic conversion of N-element to NH 3 and for H 2 generation during water splitting. Furthermore, the plausible degradation pathway in SMX was proposed and the results revealed that the SMX was mineralized by the composite further converted to NH 3 and generates H 2 during the degradation process. Thus, our study provides new insights into novel photocatalytic treatment methodologies for simultaneous degradation of SMX to produce NH 3 and H 2 as value-added compounds from antibiotic wastewaters during water treatment process. • A facile dual functional hybrid composite was prepared. • H 2 and NH 3 has been generated during photocatalytic degradation of SMX. • Heterojunction significantly enhanced SMX degradation and H 2 generation. • N-containing SMX molecule was utilized as a nitrogen source for ammonia. [ABSTRACT FROM AUTHOR]

As a fascinating approach for sustainable NH 3 production, the electrocatalytic nitrogen reduction reaction (NRR) is still hampered by low Faraday efficiency due to high energy required for inert N N triple bond activation and competitive hydrogen evolution reaction (HER). In this paper, we propose a method to increase the NRR catalytic activity by constructing bimetallic sites on boron nitride (BN) monolayer. In order to approach the efficient NRR region, the metal-based linear-scaling relationship between adsorbed intermediates is broken by synergistic effects between the bimetallic active sites. TiRu-BN was identified as an effective NRR electrocatalyst with low limiting potential (−0.28 V) and superior selectivity after systematic evaluation of the thermal stability, electrochemical stability, activity, and selectivity of 36 homo- and heteronuclear diatomic catalyst candidates. Analysis on the origin of high performance shows the screened high-performance diatomic catalyst is located in the region of moderate linear-scaling relationship breaking of intermediates. Breaking the linear scale relationship to the most significant extend does not imply the most improved catalytic activity. This work not only provides experimentally synthesizable exceptional NRR electrocatalyst candidates, but also provides theoretical guidance for practical application of efficient NRR electrocatalyst. [Display omitted] • Metal dimers anchored on defective BN monolayers for NRR investigated. • TiRu-BN was identified as high performance NRR electrocatalyst. • Synergistic effect of dual metal site breaks scaling relationship of intermediates. • High-performance catalyst shows the moderate scaling relationship breaking. [ABSTRACT FROM AUTHOR]

Herein, a series of porous N -graphyne decorated TiO 2 /Ti 3 C 2 composites (NHGTTC-x) are constructed via hydrothermal treatment of N -graphyne and Ti 3 C 2 in the presence of H 2 O 2. The added H 2 O 2 can serve as both pore-forming reagent of N -graphyne and oxidant of Ti 3 C 2 in the synthesis process. As a result, numerous TiO 2 nanoparticles in-situ generate on almost the entire surface of Ti 3 C 2 , and the porous wrinkled N -graphyne surrounds or attaches on the surface of TiO 2 /Ti 3 C 2. The highest NH 3 yield is found over the photocatalysis of NHGTTC-1% under UV–visible light for 4 h (0.306 mmol g−1), which is 3.86 times of that for pristine TiO 2 /Ti 3 C 2 (0.079 mmol g−1). Moreover, the photodegradation efficiencies of tetracycline, rhodamine B, and levofloxacin by NHGTTC-1% are 2.40 folds, 2.58, and 7.90 times greater than that of pristine TiO 2 /Ti 3 C 2 under visible light illumination. In addition, the primary active species is established to be superoxide radical (·O 2 −) in the photocatalytic decomposition process. Additionally, the enhanced mechanism of photocatalysis is methodically investigated by photocurrent, Tafel plots, electrochemical impedance, Mott-Schottky curves, etc. This study marks the first construction of porous N -graphyne/TiO 2 /Ti 3 C 2 composites, which show superior photocatalytic activity for contaminants degradation and nitrogen fixation. Porous N -graphyne modified TiO 2 /Ti 3 C 2 composites are constructed via hydrothermal method using hydrogen peroxide as pore-forming reagent. Superior photocatalytic activity for nitrogen reduction and pollutant degradation are confirmed. [Display omitted] • Porous N -graphyne/TiO 2 /Ti 3 C 2 are constructed via hydrothermal method. • The added H 2 O 2 serves as pore-forming reagent and oxidant in synthesis process. • Improved photocatalytic N 2 reduction and contaminants degradation are verified. • The conductivity and porous structure of N -graphyne contributes to enhancement. [ABSTRACT FROM AUTHOR]

Legume–rhizobium symbiotic nitrogen fixation is a highly energy-consuming process. Recent studies demonstrate that nodule-specific energy sensors play important roles in modulating nodule nitrogen fixation capacity. This opens a new field in the energy regulation of symbiotic nitrogen fixation that can provide insights into designing leguminous crops with efficient nitrogen fixation. [ABSTRACT FROM AUTHOR]

The merits of adjustable structure and composition and wide source of raw materials have convinced researchers to become more and more obsessed with the discussion of perovskite oxide materials and materials with perovskite structure in recent years. Perovskite type materials with excellent performance and well structural composition are expected to replace Pt/C, IrO 2 and RuO 2 , which are considered to be the most advanced active, valuable and cost-effective catalyst materials in the future. Therefore, finding catalysts with relatively higher economic and catalytic efficiency have always been the ideal goal of research for hydrogen production and O 2 /N 2 reduction. A large number of scholars have made significant efforts in developing various catalysts that remarkably enhance the catalytic activities of hydrogen evolution reaction (HER), oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and nitrogen reduction reaction (NRR). This review aims to summarize some significant achievements in obtaining high-performance perovskite in the main related electro-catalysis field in recent years and provide a reference for the subsequent development of perovskite. This paper introduces the detailed methodology of the preparation of perovskite and discusses the design strategy of perovskite performance enhancement as important entry points to optimize the activity of perovskite. The paper comprehensively reviews the preparation methods of various perovskite with various examples, and also compares their advantages and disadvantages. To improve perovskite performance, most of the existing design strategies are introduced and integrated and novel design schemes are also displayed. The paper finally suggests the improvement potential in perovskite activity, aiming to create better design schemes of new perovskite in the future. • Conventional and new preparation methods of perovskite oxides catalysts are summarized. • Perovskites for hydrogen generation via hydrogen evolution reaction were summarized. • Perovskites for oxygen generation via oxygen evolution reaction were summarized. • Perovskites for nitrogen fixation via nitrogen reduction reaction were summarized. • Further performance improvement strategies of perovskite catalysts for electrochemistry are summarized. [ABSTRACT FROM AUTHOR]

Multifunctional semiconductor photocatalyst with Ohmic-Schottky contact heterojunctions for hydrogen evolution reaction (HER) and nitrogen fixation (NF) were constructed by modifying CdS with bimetallic Co 2x Ni 2(1-x) P (xCNP) and thin layer Ti 3 C 2 (TLTC) containing -O x rich functional groups. Under the optimal conditions (2 % 0.2CNP@CdS/2% TLTC), it yielded a hydrogen evolution rate of up to 1.72 mmol h−1 and a nitrogen fixation rate of 656.82 μmol L−1 h−1, corresponding to an apparent quantum efficiency (AQE) of 59.81 %. The remarkable HER and NF properties can be attributed to the improved electron transfer efficiency of the double transition metal and the improved surface N 2 /NH 3 adsorption energy. The construction of Ohmic-Schottky contact heterojunctions reduced the HER overpotential and improved the separation efficiency of the photogenerated carriers. The optimized method synthesises 0.2FNP and TLTC together to form an ohmic contact Schottky heterojunction to achieve efficient photogenerated electron-hole separation and obtain high performance photocatalytic HER and NF catalysts. [Display omitted] • A simple and mild method was used to synthesize Co-doped Ni 2 P nanosheets. • Construction of ohm-Schottky heterojunctions to improve the efficiency of photogenerated carrier separation. • The composites showed excellent activity and stability in both photocatalytic hydrogen production and nitrogen fixation tests. • DFT calculations demonstrate that a small amount of Co doping improves the nitrogen adsorption energy. • DFT calculations demonstrate that bimetallic phosphides make semiconductor composites metallic. [ABSTRACT FROM AUTHOR]

Non-native plants can significantly affect biodiversity and ecological functions of local ecosystems. The effects of Kandelia obovata introduction and Spartina alterniflora invasion on benthic bacterial communities, predicted ecological functions and interactions between macrobenthos and microorganisms were studied. High-throughput sequencing of the 16S rRNA gene was used to investigate the bacterial communities in sediments covered by S. alterniflora and K. obovata at different stand ages. Bacterial communities showed obvious spatial variation. With increasing in planting age, K. obovate sediments were occupied by higher proportions of bacteria involved in degradation of organic carbon compounds, including various sulfate reduction bacteria, Bacteroidetes, Alphaproteobacteria, and pathogenic bacteria Vibrio , while the relative abundances of Actinomatinales and Sulfurovum were more abundant in younger K. obovate sites. Compared to adjacent mudflat, higher abundances of sulfate reduction bacteria were observed in S. alterniflora. This study indicated that K. obovata introduction had greater effects on bacterial communities, and sediment pH, grain size, soil organic carbon, total nitrogen and total phosphorus contents were main environmental factors affecting variation in bacterial communities. Tax4fun analysis further suggested that higher potentials of nitrogen fixation and dissimilatory sulfate reduction were observed after K. obovata restoration and S. alterniflora invasion. There were significant correlations between macrobenthos and bacterial communities, especially variations in relative abundance of infaunas and herbivores after K. obovata introduction and S. alterniflora invasion, which significantly affected bacterial communities and potentials involved in nitrogen cycling. The present study provided valuable information in scientific assessing the impacts of non-native plant disturbance on local ecosystems. [ABSTRACT FROM AUTHOR]

The persistent utilization of synthetic nitrogen fertilizers poses a significant risk to the global climate, sustainable food production, and soil health. Exploiting the diverse assemblies of diazotrophic phyllosphere bacteria can reduce the severe risks of excessive use of artificial nitrogen fertilizers. Free-living diazotrophic bacteria in the leaf endosphere and episphere contribute tremendously to N input in terrestrial ecosystems and global N cycling. Understanding the ecological processes and biological mechanisms that shape N 2 -fixers and N 2 fixation in the phyllosphere will provide novel knowledge for future plant microbiome manipulation toward sustainable agricultural production. Recent advances in PANOMICS, gene editing, single-cell omics, and Raman spectroscopy have enhanced our understanding of the interactions between N 2 -fixers and plant hosts. The importance of biological nitrogen fixation (BNF) in securing food production for the growing world population with minimal environmental cost has been increasingly acknowledged. Leaf surfaces are one of the biggest microbial habitats on Earth, harboring diverse free-living N 2 -fixers. These microbes inhabit the epiphytic and endophytic phyllosphere and contribute significantly to plant N supply and growth. Here, we summarize the contribution of phyllosphere-BNF to global N cycling, evaluate the diversity of leaf-associated N 2 -fixers across plant hosts and ecosystems, illustrate the ecological adaptation of N 2 -fixers to the phyllosphere, and identify the environmental factors driving BNF. Finally, we discuss potential BNF engineering strategies to improve the nitrogen uptake in plant leaves and thus sustainable food production. [ABSTRACT FROM AUTHOR]

• Biological nitrogen fixation is a sustainable approach for boosting growth of rice and reducing the burden of chemical fertilizers • Azotobacter and Azospirillum spp. isolates (Az2 & As5) from native soil showed promising PGP functions • The isolates Az2 and As5 showed significantly higher N 2 -ase activity and fixed more nitrogen • Combined application of Azotobacter and Azospirillum spp. isolates (Az2 & As5) promoted the growth and development of rice (Oryza sativa L. var. Khandagiri) Biological nitrogen fixation is significantly effective and sustainable field procedure for the promotion of plant growth & development and reducing the burden of chemical fertilizers. In the present investigation, plant growth promoting activities of indigenous bio-fertilizer formulations of Azotobacter and Azospirillum spp. isolated from rice pots filled with local soil of Odisha was examined. The efficacy of Azotobacter and Azospirillum spp. were assessed by selecting five isolates from each genus that were analyzed by biochemical assay like utilization and fermentation of carbohydrate, citrate, nitrate reduction activity, oxidase activity, catalase activity and phosphatase activity. The isolates (Az2 and As5) showed maximum PGP activities among all the isolates of Azotobacter and Azospirillum spp. The analyzed isolates showed variation in production of ethylene between 63.11 ± 4.23 to 121.09 ± 4.56 nmole C 2 H 4 /mg bact./h. The isolates Az2 and As5 among Azotobacter and Azospirillum spp. respectively fixed more nitrogen in culture which is 101.66 ± 9.79 (Az2) nmole and 121.09 ± 4.56 (As5) nmole C 2 H 4 /mg bact./h. The treatments T 1 (Az2) and T 2 (As5) were used as individual application of Azotobacter and Azospirillum spp. and T 3 as combined application of both the strains which had the best response in all of the developmental metrics studied. Among all treatments, T 3 performed around 23-27% better than the T 1 and T 2 individually. [ABSTRACT FROM AUTHOR]

[Display omitted] • Straw biochar addition effectively improved nitrogen fixation during composting. • Inhibiting denitrification and NH 4 +-N transformation were the main means. • Biochar addition reduced microbial numbers involved in nitrogen transformation. • The microbial conversion of NO 3 –-N and organic nitrogen were strengthened. • The effect of biochar derived from maize straw was better than that of rice straw. The application of straw biochar to chicken manure composting mitigated nitrogen loss. However, the impact of biochar derived from different types of straw on nitrogen fixation in chicken manure composting is discrepant, and the specific pathways remain unclear. Therefore, this study aimed to clarify the specific pathways of maize straw biochar (M) and rice straw biochar (R) to improve nitrogen fixation during chicken manure composting. The nitrogen losses in control (no addition, CK), M, and R composting were 51.84 %, 33.47 %, and 38.24 %, respectively, suggesting that adding straw biochar effectively improved nitrogen fixation. Microbial community analysis suggested that inhibiting denitrification and NH 4 +-N transformation by microorganisms was the primary means of improving nitrogen fixation. Meanwhile, biochar addition reduced the number of bacteria participating in nitrogen transformation and strengthened the NO 3 –-N and total organic nitrogen transformation processes, among which the effect of M composting was stronger. The stronger effect was attributed to the significant role of the core microorganisms in M composting in shifting the transformation processes of the nitrogen components (P < 0.05). Therefore, the function of different straw biochar was determined by its different impacts on the microbial community, highlighting the important role of microbial community variability. [ABSTRACT FROM AUTHOR]

• Several landraces of bambara groundnut (Vigna subterannea (L.) Verdc) exist in South Africa which are but, the most underutilized and un-researched legumes. • There is variations in the bambara groundnut landraces to the nodulation responses to a given species of rhizobium. • Bambara groundnut have promiscuous nodulation properties with different rhizobia species and host specificity rule does not apply for these legumes. • Bambara groundnut exhibit more symbiotic interaction with Rhizobia species belonging to the cowpea miscellany group. Bambara groundnut (Vigna subterranea) is one of the most underutilized and neglected legume crop used for human consumption worldwide. Unlike the common food and forage legumes, the symbiotic properties of this legume have not been studied sufficiently. This study is designed to investigate the nodulation compatibility and symbiotic performance of twelve landraces of V. subterranea with five different Rhizobia species isolated from the nodules of other legumes under glasshouse conditions. Pre-germinated seeds of each landrace planted in sterile river sand medium were inoculated with 108 cfu/ml of each rhizobium inoculum suspension and monitored with regular watering using nitrogen free Hoagland's solution for six weeks. The taxonomy and phylogeny of the five rhizobia species was determined using nucleotide sequence analysis of the 16S rRNA and recA (DNA recombination protein) genes. A concatenated multiple sequence alignment was used to construct an MLSA tree to further analyze the phylogeny of the strains. Significant differences were observed among individual bambara genotypes and rhizobia strains in terms of nodule numbers and dry weight, as well as plant biomass. Statistical analysis showed that Rhizobia strains XBD2 and XS34 identified as Bradyrhizobium zhangiangens and B. centrosematis respectively exhibited the highest nodulation compatibility in terms of nodule number and nodule dry weight with one or more bambara groundnut landraces. This study demonstrated that V. subterannea does not show preference to unique rhizobia, confirming that they are promiscuously nodulated by more than one species of rhizobium belonging mainly to the cowpea miscellany cross inoculation group. The findings of this study also provide insights into the selection and development of appropriate low cost rhizobia inoculants in the sustainable production of this underutilized legume for use by smallholder farmers in South Africa. [ABSTRACT FROM AUTHOR]

• Photosynthesis and symbiosis are among the key processes for legume development. • Salt stress significantly reduced photosynthetic activity and symbiosis in fenugreek. • Photosystem II activity was importantly enhanced in silicon treated plants under salinity. • Symbiosis parameters were improved in salt-stressed fenugreek after silicon supply. Silicon (Si) application has emerged as a promising solution to improve plant growth under stressful conditions. However, the mechanisms by which Si alleviated salt damage, especially on photosynthetic machinery and symbiosis establishment in legume plants are not fully understood. Thus, this research was designed to investigate the beneficial effects of Si-treatment on salt stress tolerance in fenugreek (Trigonella foenum graecum L.). Fenugreek plants were exposed to 150 mM NaCl with or without 3 mM Si, to evaluate the effects of Si on photosynthetic traits, biological nitrogen fixation (BNF), membrane stability and oxidative stress metabolism. Results indicated that salinity significantly decreased plant growth in terms of plant biomass and high, relative water content and photosynthetic traits, including chlorophyll content and photosystems (PSI and PSII) functions, whereas the treatment of salt-stressed fenugreek with exogenous Si remarkably improved the same traits. As compared to salt-stressed control, the fenugreek-rhizobia symbiosis was also improved under salt stress in response to Si supplementation, reflected by higher nodule number and nitrogen content. On the other hand, Si supplementation to salt-stressed fenugreek plants lead to a significant decline in malonyldialdehyde and hydrogen peroxide in both shoot and root, indicating the protective effect of Si on membrane stability. This was shown to be related to the ability of Si to boost the activities of superoxide dismutase, catalase and guaiacol peroxidase. This research suggests the protective role of Si on salt-stressed fenugreek by enhancing photosynthesis, BNF and oxidative stress metabolism. [ABSTRACT FROM AUTHOR]

The eastern Mediterranean Sea (EMS) sedimentary record is periodically interspersed with organic-rich 'sapropel' layers. Sapropels are characteristic of basin-wide anoxic events, triggered by precession-forced insolation maxima. Relatively subdued insolation maxima, however, are not always expressed as distinct sapropel events. The EMS sedimentary record is thus useful to investigate feedbacks between marine anoxia and the nitrogen (N) cycle and offers an analogue for modern deoxygenation and past oceanic anoxic events. To this end, we investigated a ∼68 kyr sedimentary record from the EMS containing the well-established sapropel S1 (deposited in two phases: S1a [∼10.5–8.5 ka BP] and S1b [∼7.8–6.1 ka BP]) and sediments timed to the ambiguous S2 sapropel (∼53 ka BP). We used lipid biomarkers of microorganisms to reconstruct key N-cycle components: (1) anaerobic ammonium oxidation (anammox) using ladderanes and a stereoisomer of bacteriohopanetetrol (BHT- x), (2) dinitrogen gas (N 2) fixation using heterocyte glycolipids, and (3) nitrification by Thaumarchaeota using crenarchaeol. Additionally, benthic foraminifera and trace metals (U, Mo, Mn) were used to reconstruct redox conditions. During S1a, abundances of Thaumarchaeota increased, likely promoted by elevated high-nutrient freshwater discharge. At this time, a combination of phosphorus supply and intensified loss of bioavailable N via water column anammox, may have reinforced anoxia by favoring diatom-diazotroph associations. During S1b, anammox is equally intense. Yet, no positive feedback on N 2 -fixation is observed, likely because diazotrophs were phosphorus limited. Instead, anammox may have provided negative feedback on anoxia by quenching primary production. Ladderanes suggest additional episodes of anammox between ∼69 to 39 cal ka BP, corresponding to brief periods of water column deoxygenation. Anoxia likely occurred at the sediment–water interface in S2-timed sediments (53–51 cal ka BP). During these episodes, ladderanes co-occur with the later eluting BHT-34 R stereoisomer. δ13C BHT-34 R indicate an anammox source, potentially synthesized by marine sedimentary anammox bacteria. No corresponding increase in diatom-diazotroph associations is observed, likely due to the oligotrophic conditions and the limited effect of sedimentary anammox on N-availability in the euphotic zone. Our results highlight various modes of operation of the N-cycle at different degrees of deoxygenation, which depend amongst others on nutrient-availability and the niche-segregation of N-loss and N 2 -fixating microorganisms. [ABSTRACT FROM AUTHOR]

In Mexico, agave has a significant cultural and economic impact via its use as a raw material for producing fermented drinks. The agave plant grows in arid and nitrogen-deficient soil where it associates with fungi and bacteria to meet nutrient demands, particularly under extreme conditions of fungal growth; this community of microorganisms is called the microbiome. In the microbiome, aromatic volatile synthesis activates the defense response, resistance to abiotic stress, and plant growth. These aromatic volatiles also impact the organoleptic characteristics of fermented beverages and are produced by microorganisms during agave fermentation. This research presents the behavior of K. marxianus cultivated in the presence of extreme and deficient nitrogen concentrations. In addition, a new biological relationship between K. marxianus ITD0090 from mezcal fermentation and Bacillus tequilensis ITD-UANL-01 is reported, confirmed by fluorescence microscopy and intracellular recovery. Our results also reveal that B. tequilensis ITD-UANL-01 is a nitrogen-fixing bacterium that provides assimilable nitrogen to K. marxianus under nitrogen starvation conditions. This phenomenon allows for 144 h of viability without nitrogen. Furthermore, this is the first report of an endosymbiont of K. marxianus ITD0090 in fermentation. [Display omitted] • Kluyveromyces marxianus ITD0090 remains viable under nitrogen starvation stress for 144 h. • Bacillus tequilensis ITD-UANL-01 is the endosymbiont identified in K. marxianus ITD0090. • B. tequilensis ITD-UANL-01 can fix nitrogen and gives to K. marxianus ITD0090 assimilable nitrogen in NH 4 form. [ABSTRACT FROM AUTHOR]

Biological nitrogen fixation (BNF) is a crucial process that provides bioavailable nitrogen and supports primary production in freshwater lake ecosystems. However, the characteristics of diazotrophic community and nitrogenase activity in freshwater lake sediments remain poorly understood. Here, we investigated the diazotrophic communities and nitrogenase activities in the sediments of three large river-connected freshwater lakes in eastern China using 15N-isotope tracing and nif H sequencing. The sediments in these lakes contained diverse nitrogenase genes that were phylogenetically grouped into Clusters I and III. The diazotrophic communities in the sediments were dominated by stochastic processes in Hongze Lake and Taihu Lake, which had heterogeneous habitats and shallower water depths, while in Poyang Lake, which had deeper water and a shorter hydraulic retention time, the assembly of the diazotrophic community in the sediments was dominated by homogeneous selection processes. Temperature and water depth were also found the key environmental factors affecting the sediment diazotrophic communities. Sediment nitrogenase activities varied in the three lakes and within distinct regions of an individual lake, ranging from 0 to 14.58 nmol/(kg·hr). Nitrogenase activity was significantly correlated with ferric iron, total phosphorus, and organic matter contents. Our results suggested that freshwater lake sediment contain high diversity of nitrogen-fixing microorganisms with potential metabolic diversity, and the community assembly patterns and nitrogenase activities varied with the lake habitat. [Display omitted] [ABSTRACT FROM AUTHOR]

• The Aspalathus species studied across thirteen locations in the Cape fynbos all obtained N from symbiosis. • In this study, location-specific and species-specific effects were found to be the main drivers of variation in symbiotic performance. • A. acuminata derived over 50% of its N nutrition from symbiosis across three different locations. • The levels of mineral nutrients in the rhizosphere soil was found to influence inter-site differences in symbiotic performance. Nitrogen fixation is important for the growth and yield of nodulated legumes. In this study, the 15N natural abundance technique was used to assess the symbiotic N nutrition of 15 Aspalathus species sampled from 13 locations. The results showed that all 15 species met part of their N requirements from N 2 fixation, as shown by the different levels of symbiotic dependency. Seven species, for example, derived 54 to 77% of their N nutrition from symbiosis, nine obtained 36 to 49% from fixation, and five species derived ˂ 20% of their N from the atmosphere. More specifically, A. acuminata and A. clada both from Worcester Langerug derived 76.5% and 72.1% N, respectively, from symbiosis, A. acuminata from Rondebosch obtained 68.4% N, A. acuminata from Kalbaskraal 59.5% N, A. aculeata from Mamesbury 56.8% N, A. divericata from Penhill 56.6% N and A. cordata from Dutoitkloof 53.9% N from the atmosphere. In contrast, A. zeyheri sampled from Kokrivier derived only 4.3% of its N from symbiosis, followed by A. capensis (13.3%) and A. carnosa (14.6%) both from Silvermine. The C/N values found for the Aspalathus species in this study were unusually high for a legume, and could suggest an ecological adaptation to the low N soils of the Cape fynbos as under such N-poor plants metabolically switch from N-containing storage compounds to N-free storage molecules such as sucrose and glycerol, glucosides, galactoses and disaccharides. [ABSTRACT FROM AUTHOR]

Piezocatalytic technology has great potential in addressing water-system pollution and countering energy crises issues. Herein, high-performance CuS/ZnO Z-scheme heterojunction piezocatalyst was prepared by environmentally friendly solid-state chemistry approach and explored piezocatalytic performances toward degradation of organic methylene blue (MB) dye pollutant and nitrogen (N 2) fixation activity under ultrasonic vibration. The CuS/ZnO piezocatalyst presents outstanding property in MB degradation process with high efficiency (94.7% in 40 min), high rate constant (0.06804 min−1) and good recyclability stability in comparison with the numerous ZnO-based piezocatalysts. In addition, this catalyst also exhibits superior piezocatalytic activity with a production rate of nitrogen fixation rate of 77.5 μmol L−1 g cat −1 h−1 in the reduction of N 2 to ammonia process, which is approximately 4-folds higher than that of pristine ZnO. Such improvement was mainly attributed to the facilitating charge carriers separation via rational construction of Z-scheme heterojunction as well as enhanced redox capacity. A novel piezocatalytic Z-scheme heterojunction mechanism of CuS/ZnO has been proposed and elucidated. This work suggests that designing highly efficient CuS/ZnO piezocatalyst will be a promising candidate material for prospects application in coping with the environmental remediation pollutants and energy crisis problems. [Display omitted] • CuS/ZnO Z-scheme heterojunction piezocatalyst was prepared by solid-state chemistry approach. • CuS/ZnO presented excellent piezocatalytic properties for degradation of MB dye and N 2 fixation activity. • Such improvement was mainly attributed to the facilitating charge carrier separation. • An innovative piezocatalytic Z-scheme heterojunction mechanism of CuS/ZnO were proposed and elucidated. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrogen reduction reaction (NRR) is a sustainable and eco-friendly process to generate ammonia (NH 3). However, there are significant challenges including low catalytic performance, instability, and poor selectivity, which hinder its rapid development. Herein, a series of two-dimensional (2D) conductive metal-organic frameworks (i.e., TM 3 (HHTT) 2 , TM = Sc, Ti, V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu and Zn) are investigated as single-atom catalysts (SACs) for NRR process by the density functional theory (DFT). The obtained results of Gibbs free energies of adsorption for N 2 , ∗NNH, ∗NH 3 , which are commonly used as activity descriptors to screen the effectiveness of catalysts, show that the Mo 3 (HHTT) 2 monolayer (among all the TM 3 (HHTT) 2 ones) can activate N N bonds, stabilize the adsorbed ∗NNH, and achieve the desorption of NH 3. The Mo 3 (HHTT) 2 monolayer also exhibits an excellent structural stability (with values of E f = −2.96 eV and U diss = 1.28 V). N 2 can be effectively reduced into NH 3 on the Mo 3 (HHTT) 2 monolayer with a low limiting potential of −0.60 V along the distal pathway. Furthermore, the σ-donation and π∗ back-donation of N 2 adsorbed onto the Mo 3 (HHTT) 2 monolayer indicates an excellent electrical conductivity of Mo 3 (HHTT) 2 , which is beneficial for the effective electron transfer during the NRR process. Furthermore, the Mo 3 (HHTT) 2 monolayer exhibits considerable selectivity for the NRR process over the hydrogen evolution reaction. Our study proved that this 2D c-MOFs carrying TM of the Mo 3 (HHTT) 2 monolayer can be used as a promising catalyst for nitrogen fixation. [Display omitted] • The potential of various conductive metal-organic frameworks for NRR were studied. • The Mo 3 (HHTT) 2 exhibits excellent NRR catalytic activity along distal pathway. • The Mo 3 (HHTT) 2 has good selectivity for the NRR rather than the HER. • The synergistic interaction of HHTT with Mo resulted in good NRR catalytic property. [ABSTRACT FROM AUTHOR]

The flux of dust deposition to the ocean and its impact on marine biological productivity are outstanding issues of the Earth's climate system. The North Pacific gyre (NPG) is the Earth's largest ecosystem and is important for marine nitrogen fixation, which is sensitive to Asian dust-regulated surface nutrient stoichiometry. Meanwhile, it is one of the least studied regions in the global ocean during the late Pleistocene, because of the extremely slow sediment accumulation and lack of biological material preservation. 232Th and 230Th concentrations recorded by hydrogenetic ferromanganese crusts in the deep NPG provide a novel and quantitative proxy of dust deposition and export productivity in this region. For this purpose, we have established an in situ U – Th isotope analytical technique on hydrogenetic ferromanganese crusts collected from the deep NPG. Iron, Mn, and Co of our samples have also been analyzed to constrain the impact of dust dissolution on the Fe geochemical cycle. Remarkably, variability of the 232Th-based dust flux over the last ∼900 ky exhibits a striking resemblance to grain-size records of the Chinese loess deposits and sea-level reconstructions but clearly decouples from the global temperature evolution. On orbital time scales, dust storms over the NPG are apparently sensitive to effects related to continental ice sheet sizes but decoupled from major global cooling during the early glaciation. While our 232Th data indicate a 2- to 3-fold variability of glacial – interglacial dust flux, scavenging of Fe, Mn, and Co in the deep NPG is much less variable through the late Pleistocene. We suggest that variable dust fluxes have a limited impact on the inventory of dissolved Fe in the deep waters of NPG, even though the scavenging of Fe has likely been regulated by glacial – interglacial paleoceanography. The paired 230Th-scavenging-based biological productivity tracks gyre sea surface temperature rather than dust flux during the last glacial cycle. We observe no correlation between dust flux and export productivity in the NPG, indicating that dust-derived Fe is not the productivity-limiting factor on orbital time scales in this region. Instead, these results imply that changes in gyre mixing and mode water formation might have led to increased supply of phosphorous and thus enhanced glacial biological carbon sequestration, with potentially stronger nitrogen fixation under higher eolian input. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrogen reduction reaction (NRR) provides a green and sustainable way to produce ammonia at ambient conditions. The key to realize highly efficient NRR is the catalysts. To design highly active electrocatalysts for NRR, the multistep mechanism involved in NRR must be clearly unraveled. Herein, single V atoms anchored on g-C 3 N 4 is identified to be an efficient electrocatalyst for NRR by screening single 3d transition metal (TM = Sc to Zn) atoms anchored by g-C 3 N 4 (TM@g-C 3 N 4) through density functional theory calculations. NRR takes place on V@g-C 3 N 4 preferentially through distal path with a relatively low limiting potential of −0.55 V. The outstanding NRR performance of V@g-C 3 N 4 is found from the peculiar electronic structure of V after anchored in the six-fold cavity of g-C 3 N 4 and the good transmitter role of V for electron transfer between N x H y species and g-C 3 N 4. Moreover, the formation energy and dissolution potential indicate that V@g-C 3 N 4 is thermodynamically and electrochemically stable and the aggregation of V atoms is unfavorable thermodynamically, signifying that the synthesis of V@g-C 3 N 4 is feasible in experiments. Our work screens out a superior noble metal-free NRR electrocatalyst and will be helpful for the development of ambient artificial nitrogen fixation. • Single V atom anchored on g-C 3 N 4 is beneficial to the adsorption of N 2 and the inhibition of hydrogen evolution reaction. • The mechanism of high activity of V@g-C 3 N 4 nitrogen reduction reaction catalyst was systematically studied. • The maximum stretching of N–N bond imply good catalytic activity, but it does not mean strong adsorption of N 2. [ABSTRACT FROM AUTHOR]

Biostimulants such as ascorbic acid (AA) and fulvic acid (FA)can enhance the efficiency of root-nodulating bacteria. This study investigates optimum concentration of these two biostimulants to maximize the Rhizobium activity and increase root size, nodulation capability, NPK uptake, yield and quality. Interaction with nitrogenase enzyme through molecular docking was also studied by using both AA and FA as ligands to better understand their inhibitory role in excess amounts. The findings of the study suggest: the combined application of both FA and AA at 200 ppm concentrations proved to be more effective than the individual application. Excellent vegetative growth was noticed which translated into an increased reproductive growth i.e statistically significant increase in number of pods per plant, fresh and dry weight of pods per plant, number of seeds per pod, total chlorophyll, carotenoids and chemical constituents of pea seeds i.e. N (16.17%), P (40.47%), K (39.96%) and protein (16.25%). These findings were substantiated by molecular docking of nitrogenase enzyme with ascorbic acid and fulvic acid. The XP docking score of ascorbic acid (−7.07 kcal mol-1) and fulvic acid (−6.908 kcal mol-1) exhibited that the optimum doses (200 ppm) should be used as higher dose or their excess amount can hinder the Rhizobium activity of nitrogen fixation by interacting with the nitrogenase enzyme. • Investigating effect of Ascorbic acid (AA) and Fulvic acid (FA) on Rhizobium activity. • Four concentrations of AA (0, 100, 200, 400 ppm) and AA (0, 100, 300 500 ppm) were applied. • Combined application of FA and AA at 200 ppm proved to be more effective. • The findings were verified by molecular docking of nitrogenase enzyme with AA and FA. • The XP docking score of AA and FA exhibited that their excess can hinder Rhizobium activity. [ABSTRACT FROM AUTHOR]

Purple non-sulfur bacteria (PNSB) show great potential for environmental and industrial biotechnology, producing microbial protein, biohydrogen, polyhydroxyalkanoates (PHAs), pigments, etc. When grown photoheterotrophically, the carbon source is typically more reduced than the PNSB biomass, which leads to a redox imbalance. To mitigate the excess of electrons, PNSB can exhibit several 'electron sinking' strategies, such as CO 2 fixation, N 2 fixation, and H 2 and PHA production. The lack of a comprehensive (over)view of these redox strategies is hindering the implementation of PNSB for biotechnology applications. This review aims to present the state of the art of redox homeostasis in phototrophically grown PNSB, presenting known and theoretically expected strategies, and discussing them from stoichiometric, thermodynamic, metabolic, and economic points of view. Based on stoichiometric expectations, purple bacteria grown on different carbon and nitrogen sources have different electron sinking requirements. Thermodynamics predict a 'hierarchy' in redox strategies: CO 2 fixation and polyhydroxyalkanoate accumulation are preferred over H 2 production. Five key redox homeostasis strategies exist in phototrophically grown purple bacteria. An economic feedstock estimation highlights opportunities for methanol and volatile fatty acids as electron donors for industrial biotechnology applications. [ABSTRACT FROM AUTHOR]

Coevolution has driven speciation and evolutionary novelty in functional traits across the Tree of Life. Classic coevolutionary syndromes such as plant–pollinator, plant–herbivore, and host–parasite have focused strongly on the fitness consequences during the lifetime of the interacting partners. Less is known about the consequences of coevolved traits for ecosystem-level processes, in particular their 'afterlife' legacies for litter decomposition, nutrient cycling, and the functional ecology of decomposers. We review the mechanisms by which traits resulting from coevolution between plants and their consumers, microbial symbionts, or humans, and between microbial decomposers and invertebrates, drive plant litter decomposition pathways and rates. This supports the idea that much of current global variation in the decomposition of plant material is a legacy of coevolution. Plant litter decomposition adds a different process and ecological context to the coevolution literature, which has thus far focused on the ecology of symbionts during their lifetimes. This context integrates the literature on how arms races between plants and their consumers (herbivores, pathogens) or mutualists (nitrogen-fixing bacteria, mycorrhizal fungi) drive the quality of plant tissue, with an important legacy for litter decomposability. We know little about recent coevolutionary decomposition legacies involving plant domestication by humans via farming, plant breeding, and modified landscapes with feedback to evolution of human brain, digestion, and dentition. How myriad coevolutionary links between invertebrates and microbial decomposers affect global carbon cycling needs further investigation. Overall, plant decomposition rates are largely the legacy of wide-ranging coevolutionary relationships. [ABSTRACT FROM AUTHOR]

In this research, comprehensive optimization strategies for mitigating nitrogen loss in pig manure compost was screened out and nitrogen cycle microbial changes revealed by metagenomic technology. Results showed the optimum combination of process conditions as C/N ratio of 25, turning frequency of twice/day, addition of biochar and inoculation with nitrogen retaining microbial agent. The nitrogen loss rate of the optimized group was 14.67%, which was 45.33% significantly lower than that of the traditional group. NH 3 , N 2 O, and NO emission significantly decreased by 42.74%, 48.93%, and 69.95%. Metagenomic analysis revealed that process optimization could change the microbial community, functional genes and metabolism pathways of the nitrogen cycling in the composting process. Nitrogen loss was mainly mitigated by increasing the enzyme activities in nitrogen assimilation (increased by 11.80%), nitrification (increased by 39.35%), and nitrogen fixation pathways (increased by 74.72%) and reducing the enzyme activities in denitrification pathways (decreased by 35.20%). The findings provided reference markers for further exploration of compost nitrogen loss. This comprehensive optimization strategies method for mitigating nitrogen loss was recommended in aerobic composting of pig manure. [ABSTRACT FROM AUTHOR]

Photocatalytic or photoelectrocatalytic nitrogen fixation is considered as a very promising way to reduce energy requirements. Here, V o -BiOBr/TiO 2 nanocomposite photoelectrode was constructed by modifying TiO 2 nanotube arrays with BiOBr nanosheets with oxygen vacancies (V o) for photoelectrocatalytic nitrogen fixation. The oxygen vacancy promotes the adsorption and activation of N 2 on the catalyst surface. The Lewis basicity of nitrogen is enhanced by transferring the photogenerated electrons on the conduction band of BiOBr to the π anti-bonding orbit of N 2 , which is more beneficial for the addition of protons. On the other hand, the heterojunction between TiO 2 and V o -BiOBr facilitates the separation of photogenerated carriers. The photogenerated holes on the valence band of TiO 2 travelled to the counter electrode to produce oxygen at a negative potential, avoiding the further oxidation of NH 3. V o -BiOBr/TiO 2 displays a high NH 3 production rate of 25.08 μg h−1 cm−2 at −0.2 V which is 3.3 times higher than that of BiOBr/TiO 2. The synergistic effect between TiO 2 and V o -BiOBr results in enhanced light absorption and higher photoelectrocatalytic efficiency for the N 2 reduction reaction. Heterostructured V o -BiOBr/TiO 2 nanotube arrays shows remarkable NRR activity with an NH 3 yield of 25.08 μg h−1 cm−2 and the oxygen vacancies in BiOBr play an important role in promoting the N 2 adsorption and activation. [Display omitted] • Heterostructured V o -BiOBr/TiO 2 nanotube arrays is constructed. • The oxygen vacancies in BiOBr promote the N 2 adsorption and activation. • The NH 3 production rate of 25.08 μg h−1 cm−2 is achieved over V o -BiOBr at −0.2 V. • V o -BiOBr/TiO 2 shows high photoelectrocatalytic fixation nitrogen stability. [ABSTRACT FROM AUTHOR]

• No competition occurred between native Psoralea pinnata and invasive A. saligna. • Each legume species associated with different rhizobia and used divergent nitrogen sources. • Australian rhizobia were naturally present in pristine Fynbos soils. • Acacia invasion and spread may not be limited by rhizobium availability in Fynbos soils. Invasive Australian acacias cause substantial biodiversity impacts in South Africa's Core Cape Subregion (CCR) via positive plant-soil feedbacks, driven by high growth rates and leaf litter input by these legumes and their associations with nitrogen-fixing rhizobia. However, it is unclear whether acacia-induced soil abiotic conditions, or the association between acacias and different types of rhizobia, or both, are driving the invasive performance of acacias. Here we aim to determine how familiar (i.e., Australian) vs. novel (i.e., South African) rhizobium associations and acacia leaf litter affect competition between the invasive Acacia saligna (Labill.) H.L.Wendl. and native Psoralea pinnata L.. We grew these two legumes alone and together in pots containing Psoralea -conditioned soils. Seedlings grown alone were subjected to Australian bradyrhizobia inoculum treatments, while seedlings grown in mixture received a combination of inoculum and topsoil conditioned by acacia leaf litter in a fully factorial design. We found that neither the addition of Australian rhizobia, nor acacia-conditioned topsoil, enhanced the performance of A. saligna. Surprisingly, these treatments also did not hinder P. pinnata 's performance relative to that of A. saligna. Next generation sequencing (NGS) data revealed that each legume species associated with distinct (and familiar) rhizobia, regardless of inoculum treatment. Acacia saligna primarily met its nitrogen requirements by utilising soil nitrogen, while P. pinnata obtained much of its nitrogen via biological fixation. This apparent differentiation in nitrogen acquisition, coupled with the unique rhizobial associations of the two species, may explain the absence of strong asymmetric competition between them. This may also explain why P. pinnata is able to persist under Acacia invasion in the field and suggests that this native legume is a good candidate for restoring acacia-invaded habitats. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the roles of selenium (Se) application on the profile of photosynthetic pigments, oxidant metabolism, flavonoids biosynthesis, nodulation, and its relation to agronomic traits of peanut plants. Two independent experiments were carried out: one conducted in soil and the other in a nutrient solution. When the plants reached the V2 growth stage, five Se doses (0, 7.5, 15, 30, and 45 μg kg−1) and four Se concentrations (0, 5, 10, and 15 μmol L−1) were supplied as sodium selenate. The concentration of photosynthetic pigments, activity of antioxidant enzymes and the concentration of total sugars in peanut leaves increased in response to Se fertilization. In addition, Se improves nitrogen assimilation efficiency by increasing nitrate reductase activity which results in a higher concentration of ureides, amino acids and proteins. Se increases the synthesis of daidzein and genistein in the root, resulting in a greater number of nodules and concentration and transport of ureides to the leaves. Se-treated plants showed greater growth, biomass accumulation in shoots and roots, yield and Se concentration in leaves and grains. Our results contribute to food security and also to increase knowledge about the effects of Se on physiology, biochemistry and biological nitrogen fixation in legume plants. • Se enhances enzymatic and non-enzymatic antioxidant metabolism of peanut plants increasing protection against abiotic stress. • Nitrogen assimilation enzymes are boosted by Se increasing amino acids, protein and crop yield of peanut plants. • Se increases isoflavonoids synthesis, nodulation and ureide production. [ABSTRACT FROM AUTHOR]

The loaded photocatalyst is an ideal material for nitrogen fixation, which does not have the problem of secondary pollution caused by powdered catalysts, and has the advantages of uniform distribution, high efficiency and easy recovery. In this paper, CuO and WO 3 were grown on copper mesh (CM) by in-situ etching and solvothermal method. The photogenerated carriers and light absorption properties were synergistically promoted with the help of oxygen vacancies and S-type heterojunctions. Under simulated visible-light conditions, a liquid-membrane type reaction was employed and the nitrogen fixation performance was significantly improved. The optimal ammonia production rate of WO 3 /CuO/CM was 3.878 × 10−2 μmol/cm2/h, which was 9.37 and 5.16 times higher than WO 3 /CM and CuO/CM, respectively. This study provides ideas for the design of recyclable heterojunction catalysts with oxygen vacancies. • Copper mesh as a copper source and substrate for synthesizing photocatalyst. • Nanoflower-like WO 3 /CuO S-type heterojunction synthesized by in situ etching and solvothermal method. • Liquid membrane reaction rode reduces the impact of nitrogen insolubility on nitrogen fixation. • Photocatalytic nitrogen fixation of WO 3 /CuO S-scheme heterojunction is reported. • WO 3 /CuO displays photocatalytic nitrogen fixation performance via S-type heterojunction and oxygen vacancies synergy. [ABSTRACT FROM AUTHOR]

As one of the most consumed chemical reagents, ammonia (NH 3) has a wide range of applications in many fields. The demand for ammonia may continue to increase with the advancement of technology and the acceleration of industrialization. The traditional high energy consumption and high pollution ammonia synthesis methods (Haber-Bosch) need to be optimized and improved to reduce environmental pollution and energy dependence. In this work, a series of Z-scheme NM/Ag@AgCl heterojunctions were prepared as catalysts for the research of photocatalytic nitrogen fixation. By in-situ photodeposition, Ag@AgCl was uniformly distributed on the NM surface, and the interfaces of different substances were tightly bonded. The SPR effect that generated by Ag nanoparticles significantly enhanced the light energy absorption performance of heterojunction materials. In the ESR spectra, the signal peak intensity of NM/Ag@AgCl was higher than that of NM under light condition. Constructing of heterojunction was beneficial to the formation of Ti3+. The strong built-in electric field among NM and AgCl promoted the generation of Z-scheme heterojunction. NM/Ag@AgCl had sufficient redox potential to overcome thermodynamic barriers and drive the catalytic reaction. Without adding any sacrificial reagent, the ammonia production of NM/Ag@AgCl-3 reached 76.7 µmol g−1 h−1 under full spectrum radiation. The rate of ammonia formation of NM/Ag@AgCl was almost seven times than that of NM. The synergistic effect between NM and Ag@AgCl optimized the photogenerated carrier separation path. This work provided a new vision for the practical application of efficient photocatalytic N 2 reduction. [Display omitted] • Z-scheme heterojunction NM/Ag@AgCl was constructed for the investigation of photocatalytic nitrogen fixation. • NM/Ag@AgCl has sufficient oxidation potential to overcome thermodynamic barriers and drive the catalytic reaction. • The SPR effect produced by Ag nanoparticles optimized the utilization of light energy by the catalyst. • NM/Ag@AgCl could generate more active species •O2˗ and •OH to timely promote the activation of adsorbed N2 and oxidation of water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bi/BiVO 4 Schottky junctions enriched with oxygen vacancies (Bi/Vo-BVO) were fabricated. • Bi/Vo-BVO exhibited 8.4-fold than BiVO 4 , in NH 3 yield, reaching 167.74 μmol·g−1·h−1. • In situ FTIR and isotopic labeling demonstrated that N of NH 4 + is derived from N 2. • N 2 -TPD and DFT suggest that ligand-unsaturated V4+ species, furnish chemisorption sites for N 2. • The synergistic photothermal electrons activation mechanism of N 2 by Bi/Vo-BVO was proposed. The modulation of active site density and localized electron concentration represents a crucial step in enhancing nitrogen activation, thereby significantly augmenting the efficiency of photocatalytic nitrogen fixation. In this paper, Bi/BiVO 4 Schottky junctions enriched with oxygen vacancies (Bi/Vo-BVO) were fabricated by in situ reduction. Compared to BiVO 4 , Bi/Vo-BVO composites exhibited 8.4-fold enhancement in ammonia synthesis yield, reaching a maximum rate of 167.74 μmol·g−1·h−1. In situ FTIR spectroscopy and isotopic labeling experiments definitively demonstrated that the nitrogen constituent of NH 4 + is derived from N 2. N 2 -TPD and DFT calculation collectively suggest that the surface of Bi/Vo-BVO, enriched with ligand-unsaturated V4+ species, furnishes a substantial array of chemisorption sites for N 2 molecules, attributed to the abundance of oxygen vacancies. In situ XPS coupled with DFT corroborate that the photoexcited electrons within the BiVO 4 valence band accumulate in the conduction band, thereby directly facilitating the activation of N 2 adsorbed at the V4+ active sites; The built-in electric field established at the interface between Bi and BiVO 4 substantially facilitates the enrichment of Bi-emitted thermal electrons within oxygen vacancies on BiVO 4 surface. These electrons subsequently migrate towards and interact with the adsorbed N 2 via the V4+ active sites. The synergistic photothermal electrons activation mechanism of N 2 not only enhances the efficiency of light energy utilization but maximizes the catalytic efficacy of the photocatalyst through the full exploitation of its intrinsic catalytic potential. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electronic and magnetic properties of Janus MoSSe monolayer are modified with single TM atom. • Mo-, Re- and Os-MoSSe candidates stand out via a four-step NRR screening strategy. • Re-MoSSe exhibits better NRR catalytic activity than the reported conventional Re-MoS 2. • Origins of high NRR activity for Mo-, Re- and Os-MoSSe are systematically revealed. Designing efficient nitrogen reduction reaction (NRR) electrocatalysts for ammonia (NH 3) synthesis under mild conditions is an attracting and challenging theme in energy electrocatalysis. Herein, the catalytic activity of a series of 3d (Cr, Mn, Fe, Co, Ni), 4d (Mo, Tc, Ru, Rh, Pd) and 5d (W, Re, Os, Ir, Pt) transition-metal (TM) atoms anchored Janus MoSSe monolayers for NRR is systematically explored by means of the first-principles calculations. A four-step NRR screening strategy (ΔG(*N 2) < 0 eV, ΔG(*N 2 → *NNH) < 0.50 eV, ΔG(*NH 2 → *NH 3) < 0.50 eV and ΔG(*N 2) < ΔG(*H)) is designed and applied to 15 TM-MoSSe systems, and only the Mo-, Re- and Os-MoSSe stand out. The reaction mechanisms of NRR on Mo-, Re- and Os-MoSSe are all via the distal pathway and exhibit excellent catalytic activity (with the limiting potentials of −0.49, −0.39 and −0.49 V, respectively), especially the Re-MoSSe. The high NRR activity of the Mo-, Re- and Os-MoSSe can originate mainly from the effective activation of N 2 , high built-in electrical field and superior electrical conductivity. Present findings may suggest a reliable and effective NRR screening strategy for the design of NRR electrocatalysts and promote the further exploration and development of novel NRR electrocatalysts. [ABSTRACT FROM AUTHOR]