Electrocatalytic Nitrogen Reduction Reaction Research Articles

Computational insight into transition metal atoms anchored on B2C3P as single‐atom electrocatalysts for nitrogen reduction reaction

NH3 is not only an important chemical raw material, but also a high energy storage chemical with zero carbon. Electrocatalytic nitrogen reduction reaction (NRR), which can be driven by clean electric energy under ambient conditions, have become a promising technology for NH3 synthesis due to their environmentally friendly properties. Due to the limitations of low yield and high overpotential, efficient catalysts are urgently needed to solve this problem. In this study, based on density functional theory method and high throughput screening strategy, the NRR was investigated on transition metal single atom anchored to two‐dimensional B2C3P surface (TM@B2C3P) as single‐atom catalysts (SACs). The results showed that V@B2C3P and Ti@B2C3P have good catalytic properties, and the limiting potentials via the enzymatic pathway were −0.10 and −0.24 V, respectively. Furthermore, the charge density difference and crystal orbital Hamilton population calculations demonstrated that the high catalytic activity can be attributed to the obvious charge transfer between TM@B2C3P and the adsorption intermediates. It is hoped that this work can play a certain role in exploring the application of SACs in NRR.

Hydrated molten salt electrolytes effectively promote electrocatalytic NH3 synthesis at low temperatures

In the field of electrocatalytic nitrogen reduction reaction (NRR), molten salt is used as a unique electrolyte due to its advantages of high N2 solubility and wide electrochemical window. However, it has failed to be widely used due to its high reaction temperature (mostly > 200 °C) and low yield. Herein, a novel low-temperature (<100 °C) electrolysis system with hydrated molten salt hybrid electrolyte is designed. This system exhibits an ammonia yield of 1.003 × 10−8 mol s−1 cm−2 (−0.7 V vs. SCE) at 60 °C. Faradaic efficiency (FE) reaches 80.45 % (−0.65 V vs. SCE). The NH3 yield and FE are increased by 18.6 and 2 times compared to the previously reported low-temperature system, respectively. Linear sweep voltammetry (LSV), in situ Raman and in situ Fourier Transform-Infrared (FT-IR) experiments show that solid crystalline water can be used as a hydrogen source to effectively promote NRR while inhibiting the hydrogen evolution reaction (HER). Molecular dynamics (MD) experiments confirm that the electrolyte system maintains a high N2 solubility and mass transfer rate.

Spin Manipulation of Co sites in Co9S8/Nb2CTx Mott-Schottky Heterojunction for Boosting the Electrocatalytic Nitrogen Reduction Reaction.

Regulating the adsorption of an intermediate on an electrocatalyst by manipulating the electron spin state of the transition metal is of great significance for promoting the activation of inert nitrogen molecules (N2) during the electrocatalytic nitrogen reduction reaction (eNRR). However, achieving this remains challenging. Herein, a novel 2D/2D Mott-Schottky heterojunction, Co9S8/Nb2CTx-P, is developed as an eNRR catalyst. This is achieved through the in situ growth of cobalt sulfide (Co9S8) nanosheets over a Nb2CTx MXene using a solution plasma modification method. Transformation of the Co spin state from low (t2g 6eg 1) to high (t2g 5eg 2) is achieved by adjusting the interface electronic structure and sulfur vacancy of Co9S8/Nb2CTx-P. The adsorption ability of N2 is optimized through high spin Co(II) with more unpaired electrons, significantly accelerating the *N2→*NNH kinetic process. The Co9S8/Nb2CTx-P exhibits a high NH3 yield of 62.62µg h-1 mgcat. -1 and a Faradaic efficiency (FE) of 30.33% at -0.40V versus the reversible hydrogen electrode (RHE) in 0.1m HCl. Additionally, it achieves an NH3 yield of 41.47µg h-1 mgcat. -1 and FE of 23.19% at -0.60V versus RHE in 0.1m Na2SO4. This work demonstrates a promising strategy for constructing heterojunction electrocatalysts for efficient eNRR.

Plasmonic‐Promoted Interatomic Hot Carriers Regulation Enhanced Electrocatalytic Nitrogen Reduction Reaction

Utilizing hot carriers for efficient plasmonic‐mediated chemical reactions (PMCRs) to convert solar energy into secondary energy is one of the most feasible solutions to the global environmental and energy crisis. Finding a plasmonic heterogeneous nanostructure with a more efficient and reasonable hot carrier transport path without affecting the intrinsic plasmonic properties is still a major challenge that urgently needs to be solved in this field. Herein, the mechanism by which plasmonic‐promoted interatomic hot electron redistribution on the surface of Au3Cu alloy nanoparticles promotes the electrocatalytic nitrogen reduction reaction (ENRR) is successfully clarified. The localized surface plasmon resonance (LSPR) effect can boost the transfer of plasmonic hot electrons from Au atoms to Cu atoms, trigger the interatomic electron regulation of Au3Cu alloy nanoparticles, enhance the desorption of ammonia molecules, and increase the ammonia yield by approximately 93.9%. This work provides an important reference for rationally designing and utilizing the LSPR effect to efficiently regulate the distribution and mechanism of plasmonic hot carriers on the surface of heterogeneous alloy nanostructures.

Plasmonic-Promoted Interatomic Hot Carriers Regulation Enhanced Electrocatalytic Nitrogen Reduction Reaction.

Utilizing hot carriers for efficient plasmonic-mediated chemical reactions (PMCRs) to convert solar energy into secondary energy is one of the most feasible solutions to the global environmental and energy crisis. Finding a plasmonic heterogeneous nanostructure with a more efficient and reasonable hot carrier transport path without affecting the intrinsic plasmonic properties is still a major challenge that urgently needs to be solved in this field. Herein, the mechanism by which plasmonic-promoted interatomic hot electron redistribution on the surface of Au3Cu alloy nanoparticles promotes the electrocatalytic nitrogen reduction reaction (ENRR) is successfully clarified. The localized surface plasmon resonance (LSPR) effect can boost the transfer of plasmonic hot electrons from Au atoms to Cu atoms, trigger the interatomic electron regulation of Au3Cu alloy nanoparticles, enhance the desorption of ammonia molecules, and increase the ammonia yield by approximately 93.9%. This work provides an important reference for rationally designing and utilizing the LSPR effect to efficiently regulate the distribution and mechanism of plasmonic hot carriers on the surface of heterogeneous alloy nanostructures.

Designing V single atom embedded carbon moiety for the electrocatalytic nitrogen reduction reaction by first principles study.

Development of an efficient electrocatalyst for the nitrogen reduction reaction (NRR) to serve as an sustainable alternative to the Haber-Bosch process has proven highly challenging. Single atom catalysts (SACs), which have the maximum atom utilization efficiency, are among the most promising candidates. Single atoms can be incorporated to a catalytic system by doping or substitution or by attaching a molecular coordination complex to a substrate and the different insertion modes allow the chemical environment to be varied. We have used DFT to investigate vanadium SACS for NRR activity with a focus on varying the coordination environment ofthe V atom. Phthalocyanine, porphyrin and graphene like coordination environments with varying N-coordination have been studied. Vanadium phthalocyanine (VphN4) is the most promising of the investigated systems. It features a high selectivity relative the HER reaction and relatively strong binding of N2relatively H, which prevents poisoning of the surface by hydrogen. VphN4also has the lowest overpotential among the studied systems. The electrocatalytic properties of VphN4deposited as a monolayer on the Ag (111) surface have been investigated. This system, which already has been prepared, shows promising properties for use as a catalytic electrode for the NRR reaction.

Optimizing the Lattice Nitrogen Coordination to Break the Performance Limitation of Metal Nitrides for Electrocatalytic Nitrogen Reduction.

Metal nitrides (MNs) are attracting enormous attention in the electrocatalytic nitrogen reduction reaction (NRR) because of their rich lattice nitrogen (Nlat) and the unique ability of Nlat vacancies to activate N2. However, continuing controversy exists on whether MNs are catalytically active for NRR or produce NH3 via the reductive decomposition of Nlat without N2 activation in the in situ electrochemical conditions, let alone the rational design of high-performance MN catalysts. Herein, we focus on the common rocksalt-type MN(100) catalysts and establish a quantitative theoretical framework based on the first-principles microkinetic simulations to resolve these puzzles. The results show that the Mars-van Krevelen mechanism is kinetically more favorable to drive the NRR on a majority of MNs, in which Nlat plays a pivotal role in achieving the Volmer process and N2 activation. In terms of stability, activity, and selectivity, we find that MN(100) with moderate formation energy of Nlat vacancy (E vac) can achieve maximum activity and maintain electrochemical stability, while low- or high-E vac ones are either unstable or catalytically less active. Unfortunately, owing to the five-coordinate structural feature of Nlat on rocksalt-type MN(100), this maximum activity is limited to a yield of NH3 of only ∼10-15 mol s-1 cm-2. Intriguingly, we identify a volcano-type activity-regulating role of the local structural features of Nlat and show that the four-coordinate Nlat can exhibit optimal activity and overcome the performance limitation, while less coordinated Nlat fails. This work provides, arguably for the first time, an in-depth theoretical insight into the activity and stability paradox of MNs for NRR and underlines the importance of reaction kinetic assessment in comparison with the prevailing simple thermodynamic analysis.

Computational study on single atom anchored on B2C3P monolayer as electrocatalysts for nitrogen reduction reaction

NH3 is an indispensable raw material for the synthesis of life compounds, as well as an intermediate of energy storage materials with high hydrogen content and clean energy carrier. Recently, with the development of electrocatalytic nitrogen reduction reaction (NRR), a new method of green and efficient NH3 synthesis has been found. The key of this method is to design the catalyst with high activity and selectivity. Herein, the catalytic activity of noble metal single atom supported on B2C3P (NM@B2C3P) as electrocatalysts for the NRR was explored by using the first-principles calculation. And the main basis for characterizing the catalyst activity was determined, Ir@B2C3P was successfully screened, which not only have thermodynamic stability, but also exhibit excellent NRR activity with low energy barrier of 0.513 eV and good selectivity. Meanwhile, the analysis of electronic properties also revealed the reason for the high catalytic activity.

Efficient nitrogen-doped graphene supported heteronuclear diatomic electrocatalyst for nitrogen reduction reaction: D-band center assisted rapid screening

In recent years, the electrocatalytic nitrogen reduction reaction (NRR) has attracted considerable attention as a promising method for ammonia synthesis. Currently, various diatomic catalysts (DACs) composed of metal and non-metal combinations have been studied and reported for the NRR. These catalysts have been proven the ability to lower the reaction overpotential and enhance its activity. Among them, DACs supported on two-dimensional nitride materials have been widely applied in the NRR. In this work, ten heteronuclear diatomic catalysts supported on nitrogen-doped graphene were constructed. The research results demonstrated that MoCrN6-G exhibited the best catalytic performance among these catalysts due to its lowest overpotential (0.45 V) and low desorption free energy (0.15 eV) of NH3, as well as a higher selectivity for NRR compared to the hydrogen evolution reaction. It is worth emphasizing that the d-band center (εd) is considered as a descriptor for rapidly screening efficient NRR electrocatalysts, further guiding the rational design of catalysts.

Application of Fe3O4@MoS2 & Co@MoS2 for Electrocatalytic Nitrogen Reduction Reaction Under the Magnetic Field

Ammonia, one of the most essential raw ingredient for fertilizers, pharmaceuticals and neutralization. However, the widespread production of ammonia heavily depends on the Haber-Bosch process, which entails substantial use of fossil fuels due to the demanding reaction conditions involving high pressure and temperature. Consequently, finding a sustainable method for synthesizing ammonia becomes crucial in addressing environmental pollution and mitigating energy crises.In order to improve the efficiency of ammonia production, using materials with high catalytic activity is an important factor. Traditional noble metals are recognized as the best catalytic materials. Nevertheless, the high cost and rarity of noble metals make their development and application has haven limited a lot. In recent years, two-dimensional materials attracted the attention of scientists in the field of catalysis. Among them, Molybdenum disulfide has a unique crystal structure and properties. Therefore, we aim to create a heterostructure by doping Co or incorporating Fe3O4 into MoS2, resulting in a material with either paramagnetic or ferromagnetic properties. We intend to observe the electrochemical performance of these materials under an applied magnetic field to further substantiate the influence of the magnetic field on electrocatalytic performance. Eventually, we successfully improved the performance of Nitrogen Reduction Reaction under the magnetic field. In the test of electrochemical performance at -0.04V (vs. RHE), we successfully increased the Faradaic efficiency of Fe3O4@1T-MoS2 from 32.67 to 37.16. Simultaneously, we elevated the Faradaic efficiency of Co@1T-MoS2 from 22% to 35%. From the result, we further confirmed that with the adding of magnetic field our catalyst can reach a better NRR performance. key word: nitrogen reduction reaction, Fe3O4@1T-MoS2, Cobalt-doped 1T phase molybdenum disulfide, magnetic field

In Situ Characterization Techniques for Electrochemical Nitrogen Reduction Reaction.

The electrochemical reduction of nitrogen to produce ammonia is pivotal in modern society due to its environmental friendliness and the substantial influence that ammonia has on food, chemicals, and energy. However, the current electrochemical nitrogen reduction reaction (NRR) mechanism is still imperfect, which seriously impedes the development of NRR. In situ characterization techniques offer insight into the alterations taking place at the electrode/electrolyte interface throughout the NRR process, thereby helping us to explore the NRR mechanism in-depth and ultimately promote the development of efficient catalytic systems for NRR. Herein, we introduce the popular theories and mechanisms of the electrochemical NRR and provide an extensive overview on the application of various in situ characterization approaches for on-site detection of reaction intermediates and catalyst transformations during electrocatalytic NRR processes, including different optical techniques, X-ray-based techniques, electron microscopy, and scanning probe microscopy. Finally, some major challenges and future directions of these in situ techniques are proposed.

Screening and comparison of 18 transition metal atoms doped to modulate the electrocatalytic synthesis of ammonia with multi-S vacancies MoS2: A study of density functional theory

Electrocatalytic nitrogen reduction reaction (NRR) represents a promising approach for the sustainable production of ammonia (NH3). However, current electrocatalysts exhibit limitations in terms of active sites, high reaction potential, and poor reaction selectivity. Consequently, there is a pressing need for the development of NRR electrocatalysts with high activity and selectivity under mild conditions. Among them, defect engineering and transition metal doping are two effective methods to improve the electronic structure of catalysts. In this paper, density functional theory was used to study the activity of electrocatalytic NRR on Molybdenum disulfide (MoS2) surfaces with 1–4 S vacancy numbers (VSx–MoS2, x = 1–4) and transition metal (TM)-doped VS3–MoS2 (TM@VS3–MoS2). Both VSx–MoS2 showed better structural stability, with S vacancy defects altering the electronic structure of the surface. As more Mo atoms were exposed on the surface of the structure, the adsorption of N2 gradually enhanced and the reaction was more inclined to undergo NRR. Further investigation of 18 TM-doped VS3–MoS2 revealed that the doping of Sc, Ti, V, Y, Zr and Nb atoms effectively inhibits the hydrogen precipitation reaction and reduced the energy of NH3 desorption, which contributed to the continuation of the reaction. Therefore, the improvement of MoS2 electrocatalytic NRR performance can be achieved by constructing S vacancies and TM doping to provide a better basis and reference for experimental exploration.

Single Atom Catalysts Based on Earth-Abundant Metals for Energy-Related Applications.

Anthropogenic activities related to population growth, economic development, technological advances, and changes in lifestyle and climate patterns result in a continuous increase in energy consumption. At the same time, the rare metal elements frequently deployed as catalysts in energy related processes are not only costly in view of their low natural abundance, but their availability is often further limited due to geopolitical reasons. Thus, electrochemical energy storage and conversion with earth-abundant metals, mainly in the form of single-atom catalysts (SACs), are highly relevant and timely technologies. In this review the application of earth-abundant SACs in electrochemical energy storage and electrocatalytic conversion of chemicals to fuels or products with high energy content is discussed. The oxygen reduction reaction is also appraised, which is primarily harnessed in fuel cell technologies and metal-air batteries. The coordination, active sites, and mechanistic aspects of transition metal SACs are analyzed for two-electron and four-electron reaction pathways. Further, the electrochemical water splitting with SACs toward green hydrogen fuel is discussed in terms of not only hydrogen evolution reaction but also oxygen evolution reaction. Similarly, the production of ammonia as a clean fuel via electrocatalytic nitrogen reduction reaction is portrayed, highlighting the potential of earth-abundant single metal species.

La doped-Fe2(MoO4)3 with the synergistic effect between Fe2+/Fe3+ cycling and oxygen vacancies enhances the electrocatalytic synthesizing NH3

The electrocatalytic nitrogen reduction reaction (NRR) is a crucial process in addressing energy shortages and environmental concerns by synthesizing the NH3. However, the difficulty of N2 activation and fewer NRR active sites limit the application of NRR. Therefore, the NRR performance can be improved by rapid electron transport paths to participate in multi-electron reactions and N2 activation. Doping with transition metal element is a viable strategy to provide electrons and electronic channels in the NRR. This study focuses on the synthesis of Fe2(MoO4)3 (FeMo) and x%La-doped FeMo (x = 3, 5, 7, and 10) using the hydrothermal method. La-doping creates electron transport channels Fe2+-O2−-Fe3+ and oxygen vacancies, achieving an equal molar ratio of Fe2+/Fe3+. This strategy enables the super-exchange in Fe2+-O2−-Fe3+, and then enhances electron transport speed for a rapid hydrogenation reaction. Therefore, the synergistic effect of Fe2+/Fe3+ cycling and oxygen vacancies improves the NRR performance. Notably, 5%La-FeMo demonstrates the superior NRR performance (NH3 yield rate: 29.6 μg h−1 mgcat−1, Faradaic efficiency: 5.8%) at −0.8 V (vs. RHE). This work analyzes the influence of the catalyst electronic environment on the NRR performance based on the effect on different valence states of ions on electron transport.

Catalysts with Trimetallic Sites on Graphene-like C2N for Electrocatalytic Nitrogen Reduction Reaction: A Theoretical Investigation.

Electrocatalytic nitrogen reduction reaction (NRR) is a green and highly efficient way to replace the industrial Haber-Bosch process. Herein, clusters consisting of three transition metal atoms loaded on C2N as NRR electrocatalysts are investigated using density functional theory (DFT). Meanwhile, Ca was introduced as a promoter and the role of Ca in NRR was investigated. It was found that Ca anchored to the catalyst can act as an electron donor and effectively promote the activation of N2 on M3. In both M3@C2N and M3Ca@C2N (M=Fe, Co, Ni), the limiting potential (UL) is less negative than that of the Ru(0001) surface and has the ability to suppress the competitive hydrogen evolution reaction (HER). Among them, Fe3@C2N is suggested to be the most promising candidate for NRR with high thermal stability, strong N2 adsorption ability, low limiting potential, and good NRR selectivity. The concepts of trimetallic sites and alkaline earth metal promoters in this work provide theoretical guidance for the rational design of atomically active sites in electrocatalytic NRR.

Screening transition metal and nonmetal atoms co-doped graphyne as efficient single-atom catalysts for nitrogen reduction

Despite the great potential of electrocatalytic nitrogen reduction reaction (NRR) for more sustainable and energy-efficient ammonia (NH3) production, significant challenges remain, including low activity and poor selectivity of currently available catalysts. In this study, we systematically investigate the electrocatalytic NRR performance of 43 types of single-atom catalysts (SACs) constructed by introducing single transition metal (TM) or/and nonmetal (NM) atoms in graphyne (TM-NM-GY) through first-principles calculations. It is found that Mn-, Os-, B-, Ti-B-, V-B-, Cr-B-, Ru-B-, and Os-B-GY exhibit remarkable efficiency for NRR, showcasing overpotentials lower than 0.34 V. Particularly, Os-B-GY stands out by demonstrating ultra-high catalytic activity, selectivity, and stability for NRR as well as good experimental feasibility, with an impressively low overpotential of merely 0.13 V. The co-doping of Os and B allows for adjusting moderately positive charge densities around Os, which enables strong d-2π* coupling between Os and N2. As a result, the N≡N triple bond is remarkably weakened, facilitating the subsequent NRR process. Moreover, benefiting from the cooperative doping of NM and TM, the potential limiting step is changed, which breaks the inherent linear volcanic relationship between the free energy of the critical intermediate N2H* and limiting potential (UL) on the sole TM-doped system, further enhancing the activity and selectivity. We anticipate that the insights gained from this comprehensive and systematic study can offer valuable guidance for the design and synthesis of novel and highly efficient SACs toward NRR.

Combined Effect of Pressure and Temperature on Nitrogen Reduction Reaction in Water

The synthesis of ammonia starting from nitrogen and using electrochemical processes is considered an interesting strategy to produce ammonia in a sustainable way. However, it requires not only the development of efficient catalysts for nitrogen reduction but also the optimization of the operating conditions of the employed electrochemical devices. In this work, we optimize the kinetics and the thermodynamics of the electrocatalytic nitrogen reduction reaction in water by developing a pressurized H-cell that may operate at temperatures up to 80 °C. Ni foam with low Au loading (0.08 mg cm−2) has been adopted as a catalyst at the cathode. Ammonia has been produced during chronoamperometry experiments in a saturated N2 atmosphere and measured by the indophenol blue method. The effect of voltage, temperature, and pressure has been studied. The nitrogen reduction experiments have been repeated under saturated Ar. To remove contributions due to environmental contamination, we determined the net value as the difference between the produced ammonia in N2 and in Ar. The ammonia yield increases by increasing the temperature and the pressure. The best results have been obtained by using the combined effects of temperature and pressure. Operating at 5 bar of saturated N2 and 75 °C, a production rate of 6.73 μg h−1·cm−2 has been obtained, a value corresponding to a 5-fold enhancement, compared to that obtained under ambient conditions and room temperature.

Repairable body-centered cubic Fe0 anchoring on porous hollow nitrogen-doped carbon spheres with adjusting electron distribution for efficient electrocatalytic ammonia synthesis

Electrocatalytic nitrogen reduction reaction (ENRR) is a promising and efficient method for ammonia production. However, ENRR is restricted by the adsorption and activation of N2. Herein, an efficient nitrogen reduction reaction (NRR) electrocatalyst loaded with zero valent iron (ZVI) particles onto porous nitrogen-doped carbon (NC) hollow spheres is reported. The optimal Fe@10N3C-950 exhibits excellent performance with high ammonia (NH3) yield (152.28 µg h−1 mgcat−1) and Faradaic efficiency (FE, 54.55 %) at − 0.3 V (versus reversible hydrogen electrode, vs. RHE). Bader charge shows that the adsorbed N2 acquires more electrons from Fe sites with body-centered cubic (BCC) structure to better activate N2. Moreover, i-t experiments are performed before electrocatalytic NH3 production to effectively eliminate the effect of oxidation on ZVI and thus, maintain high ENRR activity for Fe@10N3C-950. Theoretical calculations indicate that nitrogen doping not only reduces the Gibbs free energy of rate determining step (RDS), but the BCC-structured Fe can also decrease the energy barriers of N2 activation and RDS.

The dual-transition-metal dichalcogenide monolayers anchored with Mn dimer: Promising electrocatalysts for efficient nitrogen reduction reaction

Due to its great efficiency, the electrocatalytic nitrogen reduction reaction (NRR) presents itself as a viable and eco-friendly substitute for the traditional Haber-Bosch ammonia production process. However, it is still a formidable task to find electrocatalysts with high activity and selectivity. In this study, a series of transition metals (TM = Ti–Ni, Zr–Mo, Ru–Pd, and Hf–Pt) anchored on 1T′-dual-transition-metal dichalcogenides (1T′-d-TMDs) monolayers (TM2@1T′-CrCoS4) were systematically investigated as electrocatalysts for NRR using first-principles calculations based on density functional theory. Based on a thorough examination of selectivity, high activity, and stability, Mn2@1T′-CrCoS4 and Co2@1T′-CrCoS4 demonstrate exceptional NRR performance. With a limiting potential of −0.11 V, Mn2@1T′-CrCoS4 stood out among them in terms of catalytic activity, favoring the enzymatic pathway. Furthermore, ab initio molecular dynamics (AIMD) simulations were used to assess the dynamic stability of Mn2@1T′-CrCoS4 and Co2@1T′-CrCoS4. To determine the source of increased activities, the density of states (DOS), charge density difference, and crystal orbital Hamilton population analysis were used. According to our research, the 1T′-d-TMDS is a viable substrate for the development of effective NRR catalysts and offers a platform for electrocatalyst experimentation.

Controllable Construction of a Mo2C/MoO2 Interface with an Ideal Mo2C/MoO2 Ratio for Efficient Electrocatalytic Nitrogen Reduction to Ammonia.

Electrocatalytic nitrogen reduction reaction (NRR) is considered to be a viable contender for the production of NH3. However, due to the sluggish adsorption and activation of the electrocatalyst toward inert N2 molecules, there is an urgent need for developing effective catalysts to facilitate the reaction. Inspired by natural nitrogenase, in which Mo atoms are the active centers, Mo-based electrocatalysts have received considerable attention, but further exploration is still necessary. Interface-engineered electrocatalysts can effectively optimize the absorption and activation of the catalytic active center for N2 and thus improve the electrocatalytic activity of NRR. However, the lack of studies for controllably constructing an optimal ratio of two phases at the interface hinders the development of NRR electrocatalysts. Herein, a series of Mo2C/MoO2 interface-engineered electrocatalysts with various Mo2C/MoO2 ratios were constructed by controlling the Y dosages. The controlled experimental results verified that the catalytic activity of NRR, the dosage of Y, and the ratio of Mo2C/MoO2 were strongly correlated. Density functional theory calculations show that the C-Mo-O coordination at the Mo2C/MoO2 interface can optimize the reaction path and reduce the energy barrier of the reaction intermediates, thereby enhancing the reaction kinetics of NRR.