Self‐Limited on‐Site Conversion of MoO3 Nanodots into Vertically Aligned Ultrasmall Monolayer MoS2 for Efficient Hydrogen Evolution

MoS₂ has emerged as a promising alternative electrocatalyst for the hydrogen evolution reaction (HER) due to high intrinsic per‐site activity on its edge sites and S‐vacancies. However, a significant challenge is the limited density of such sites. Reducing the size and layer number of MoS₂ and vertically aligning them would be an effective way to enrich and expose such sites for HER. Herein, a facile self‐limited on‐site conversion strategy for synthesizing monolayer MoS₂ in a couple of nanometers which are highly dispersed and vertically aligned on 3D porous carbon sheets is reported. It is discovered that the preformation of well‐dispersed MoO₃ nanodots in 1–2 nm as limited source is the key for the fabrication of such an ultrasmall MoS₂ monolayer. As indicated by X‐ray photoelectron spectroscopy and electron spin resonance data, these ultrasmall MoS₂ monolayers are rich in accessible S‐edge sites and vacancies and the smaller MoS₂ monolayers the more such sites they have, leading to enhanced electrocatalytic activity with a low overpotential of 126 mV at 10 mA cm^?2 and 140 mV at 100 mA mg^?1 for HER. This state‐of‐the‐art performance for MoS₂ electrocatalysts enables the present strategy as a new avenue for exploring well‐dispersed ultrasmall nanomaterials as efficient catalysts.     

Rational Design of Hydroxyl‐Rich Ti3C2Tx MXene Quantum Dots for High‐Performance Electrochemical N2 Reduction

To enable an efficient and cost‐effective electrocatalytic N₂ reduction reaction (NRR) the development of an electrocatalyst with a high NH₃ yield and good selectivity is required. In this work, Ti₃C₂T_x MXene‐derived quantum dots (Ti₃C₂T_x QDs) with abundant active sites enable the development of efficient NRR electrocatalysts. Given surface functional groups play a key role on the electrocatalytic performance, density functional theory calculations are first conducted, clarifying that hydroxyl groups on Ti₃C₂T_x offer excellent NRR activity. Accordingly, hydroxyl‐rich Ti₃C₂T_x QDs (Ti₃C₂OH QDs) are synthesized as NRR catalysts by alkalization and intercalation. This material offers an NH₃ yield and Faradaic efficiency of 62.94 µg h^?1 mg^?1_cat. and 13.30% at ?0.50 V, respectively, remarkably higher than reported MXene catalysts. This work demonstrates that MXene catalysts can be mediated through the optimization of both QDs sizes and functional groups for efficient ammonia production at room temperature.     

Unsaturated Sulfur Edge Engineering of Strongly Coupled MoS2 Nanosheet–Carbon Macroporous Hybrid Catalyst for Enhanced Hydrogen Generation

The low hydrogen adsorption free energy and strong acid/alkaline resistance of layered MoS₂ render it an excellent pH‐universal electrocatalyst for hydrogen evolution reaction (HER). However, the catalytic activity is dominantly suppressed by its limited active‐edge‐site density. Herein, a new strategy is reported for making a class of strongly coupled MoS₂ nanosheet–carbon macroporous hybrid catalysts with engineered unsaturated sulfur edges for boosting HER catalysis by controlling the precursor decomposition and subsequent sodiation/desodiation. Both surface chemical state analysis and first‐principles calculations verify that the resultant catalysts exhibit a desirable valence‐electron state with high exposure of unsaturated sulfur edges and an optimized hydrogen adsorption free energy, significantly improving the intrinsic HER catalytic activity. Such an electrocatalyst exhibits superior and stable catalytic activity toward HER with small overpotentials of 136 mV in 0.5 m H₂SO₄ and 155 mV in 1 m KOH at 10 mA cm^?2, which is the best report for MoS₂–C hybrid electrocatalysts to date. This work paves a new avenue to improve the intrinsic catalytic activity of 2D materials for hydrogen generation.     

A Review of Electrocatalytic Reduction of Dinitrogen to Ammonia under Ambient Conditions

The production of ammonia (NH₃) from molecular dinitrogen (N₂) under mild conditions is one of the most attractive topics in the field of chemistry. Electrochemical reduction of N₂ is promising for achieving clean and sustainable NH₃ production with lower energy consumption using renewable energy sources. To date, emerging electrocatalysts for the electrochemical reduction of N₂ to NH₃ at room temperature and atmospheric pressure remain largely underexplored. The major challenge is to achieve both high catalytic activity and high selectivity. Here, the recent progress on the electrochemical nitrogen reduction reaction (NRR) at ambient temperature and pressure from both theoretical and experimental aspects is summarized, aiming at extracting instructive perceptions for future NRR research activities. The prevailing theories and mechanisms for NRR as well as computational screening of promising materials are presented. State‐of‐the‐art heterogeneous electrocatalysts as well as rational design of the whole electrochemical systems for NRR are involved. Importantly, promising strategies to enhance the activity, selectivity, efficiency, and stability of electrocatalysts toward NRR are proposed. Moreover, ammonia determination methods are compared and problems relating to possible ammonia contamination of the system are mentioned so as to shed fresh light on possible standard protocols for NRR measurements.     

Anchoring PdCu Amorphous Nanocluster on Graphene for Electrochemical Reduction of N2 to NH3 under Ambient Conditions in Aqueous Solution

As an alternative approach for N₂ fixation under milder conditions, electrocatalytic nitrogen reduction reaction (NRR) represents a very attractive strategy for sustainable development and N₂ cycle to store and utilize energy from renewable sources. However, the research on NRR electrocatalysts still mainly focuses on noble metals, while, high costs and limited resources greatly restrict their large‐scale applications. Herein, as a proof‐of‐concept experiment, taking PdCu amorphous nanocluster anchored on reduced graphene oxide (rGO) as NRR catalysts, the optimum Pd_0.2Cu_0.8/rGO composite presents a synergistic effect and shows superior electrocatalytic performance toward NRR under ambient conditions (yield: 2.80 µg h^?1 mg_cat.^?1 at ?0.2 V vs reversible hydrogen electrode), which is much higher than that of monometallic, especially noble metal, counterparts. The superior catalytic performance of alloy catalysts with low noble metal loading would strongly spur interest toward more researches on NRR catalysts in the future.     

Rational Design of Graphene‐Supported Single Atom Catalysts for Hydrogen Evolution Reaction

The proper choice of nonprecious transition metals as single atom catalysts (SACs) remains unclear for designing highly efficient electrocatalysts for hydrogen evolution reaction (HER). Herein, reported is an activity correlation with catalysts, electronic structure, in order to clarify the origin of reactivity for a series of transition metals supported on nitrogen‐doped graphene as SACs for HER by a combination of density functional theory calculations and electrochemical measurements. Only few of the transition metals (e.g., Co, Cr, Fe, Rh, and V) as SACs show good catalytic activity toward HER as their Gibbs free energies are varied between the range of –0.20 to 0.30 eV but among which Co‐SAC exhibits the highest electrochemical activity at 0.13 eV. Electronic structure studies show that the energy states of active valence d_z² orbitals and their resulting antibonding state determine the catalytic activity for HER. The fact that the antibonding state orbital is neither completely empty nor fully filled in the case of Co‐SAC is the main reason for its ideal hydrogen adsorption energy. Moreover, the electrochemical measurement shows that Co‐SAC exhibits a superior hydrogen evolution activity over Ni‐SAC and W‐SAC, confirming the theoretical calculation. This systematic study gives a fundamental understanding about the design of highly efficient SACs for HER.     

In Situ Fragmented Bismuth Nanoparticles for Electrocatalytic Nitrogen Reduction

The electrochemical nitrogen reduction reaction (NRR) is a promising alternative to the energy‐intensive Haber–Bosch process for ammonia synthesis. Among the possible electrocatalysts, bismuth‐based materials have shown unique NRR properties due to their electronic structures and poor hydrogen evolution activity. However, identification of the active sites and reaction mechanism is still difficult due to structural and chemical changes under reaction potentials. Herein, in situ Raman spectroscopy, complemented by electron microscopy, is employed to investigate the structural and chemical transformation of the Bi species during the NRR. Nanorod‐like bismuth‐based metal–organic frameworks are reduced in situ and fragment into densely contacted Bi⁰ nanoparticles under the applied potentials. The fragmented Bi⁰ nanoparticles exhibit excellent NRR performance in both neutral and acidic electrolytes, with an ammonia yield of 3.25 ± 0 .08 µg cm^?2 h^?1 at ?0.7 V versus reversible hydrogen electrode and a Faradaic efficiency of 12.11 ± 0.84% at ?0.6 V in 0.10 m Na₂SO₄. Online differential electrochemical mass spectrometry detects the production of NH₃ and N₂H₂ during NRR, suggesting a possible pathway through two‐step reduction and decomposition. This work highlights the importance of monitoring and optimizing the electronic and geometric structures of the electrocatalysts under NRR conditions.     

Molybdenum Disulfide/Nitrogen‐Doped Reduced Graphene Oxide Nanocomposite with Enlarged Interlayer Spacing for Electrocatalytic Hydrogen Evolution

Facile design of low‐cost and highly active catalysts from earth‐abundant elements is favorable for the industrial application of water splitting. Here, a simple strategy to synthesize an ultrathin molybdenum disulfide/nitrogen‐doped reduced graphene oxide (MoS₂/N‐RGO‐180) nanocomposite with the enlarged interlayer spacing of 9.5 Å by a one‐step hydrothermal method is reported. The synergistic effects between the layered MoS₂ nanosheets and N‐doped RGO films contribute to the high activity for hydrogen evolution reaction (HER). MoS₂/N‐RGO‐180 exhibits the excellent catalytic activity with a low onset potential of ?5 mV versus reversible hydrogen elelctrode (RHE), a small Tafel slope of 41.3 mV dec^?1, a high exchange current density of 7.4 × 10^?4 A cm^?2, and good stability over 5 000 cycles under acidic conditions. The HER performance of MoS₂/N‐RGO‐180 nanocomposite is superior to the most reported MoS₂‐based catalysts, especially its onset potential and exchange current density. In this work, a novel and simple method to the preparation of low‐cost MoS₂‐based electrocatalysts with the extraordinary HER performance is presented.     

High‐Performance Electrocatalytic Conversion of N2 to NH3 Using Oxygen‐Vacancy‐Rich TiO2 In Situ Grown on Ti3C2Tx MXene

To achieve the energy‐effective ammonia (NH₃) production via the ambient‐condition electrochemical N₂ reduction reaction (NRR), it is vital to ingeniously design an efficient electrocatalyst assembling the features of abundant surface deficiency, good dispersibility, high conductivity, and large surface specific area (SSA) via a simple way. Inspired by the fact that the MXene contains thermodynamically metastable marginal transition metal atoms, the oxygen‐vacancy‐rich TiO₂ nanoparticles (NPs) in situ grown on the Ti₃C₂T_x nanosheets (TiO₂/Ti₃C₂T_x) are prepared via a one‐step ethanol‐thermal treatment of the Ti₃C₂T_x MXene. The oxygen vacancies act as the main active sites for the NH₃ synthesis. The highly conductive interior untreated Ti₃C₂T_x nanosheets could not only facilitate the electron transport but also avoid the self‐aggregation of the TiO₂ NPs. Meanwhile, the TiO₂ NPs generation could enhance the SSA of the Ti₃C₂T_x in return. Accordingly, the as‐prepared electrocatalyst exhibits an NH₃ yield of 32.17 µg h^?1 mg^?1_cat. at ?0.55 V versus reversible hydrogen electrode (RHE) and a remarkable Faradaic efficiency of 16.07% at ?0.45 V versus RHE in 0.1 m HCl, placing it as one of the most promising NRR electrocatalysts. Moreover, the density functional theory calculations confirm the lowest NRR energy barrier (0.40 eV) of TiO₂ (101)/Ti₃C₂T_x compared with Ti₃C₂T_x or TiO₂ (101) alone.     

Defect‐Engineered Ultrathin δ‐MnO2 Nanosheet Arrays as Bifunctional Electrodes for Efficient Overall Water Splitting

Recently, defect engineering has been used to intruduce half‐metallicity into selected semiconductors, thereby significantly enhancing their electrical conductivity and catalytic/electrocatalytic performance. Taking inspiration from this, we developed a novel bifunctional electrode consisting of two monolayer thick manganese dioxide (δ‐MnO₂) nanosheet arrays on a nickel foam, using a novel in‐situ method. The bifunctional electrode exposes numerous active sites for electrocatalytic rections and displays excellent electrical conductivity, resulting in strong performance for both HER and OER. Based on detailed structure analysis and density functional theory (DFT) calculations, the remarkably OER and HER activity of the bifunctional electrode can be attributed to the ultrathin δ‐MnO₂ nanosheets containing abundant oxygen vacancies lead to the formation od Mn³⁺ active sites, which give rise to half‐metallicity properties and strong H₂O adsorption. This synthetic strategy introduced here represents a new method for the development of non‐precious metal Mn‐based electrocatalysts for eddicient energy conversion.     

Nickel–Copper Alloy Encapsulated in Graphitic Carbon Shells as Electrocatalysts for Hydrogen Evolution Reaction

Searching for cost‐effective and high‐performance electrocatalysts for hydrogen production is of paramount importance. Herein, nickel‐copper (NiCu) alloy nanoparticles are encapsulated into graphitic shells via an ambient‐pressure chemical vapor deposition process. The resulting carbon‐encapsulated NiCu (denoted as NiCu@C) composite possesses a well‐defined core–shell structure with tunable thicknesses of the shells and is examined as electrocatalysts for the hydrogen evolution reaction (HER) in acidic, neutral, and alkaline solutions. Electrochemical measurements indicate that the activity of the NiCu@C highly depends on the thickness of the shell. Single‐layered graphene encapsulated NiCu nanoparticles show remarkable HER activity and durability. To obtain a current density of 10 mA cm^?2, overpotentials of 48, 164, and 74 mV are needed in electrolyte solutions with pH = 0, 7, and 14, respectively. Such low overpotentials render the composite as one of the most active nonprecious electrocatalysts. Accelerated durability tests demonstrate that the NiCu@C catalysts exhibit excellent stability. Density function theory calculations are conducted to investigate the electronic structures of the NiCu@C. It is found that the representative Ni₄₃Cu₁₂@C₂₄₀ model shows an ideal adsorption energy of hydrogen (?0.03 eV), manifesting its high HER activity.     

Construction of Defect‐Rich RhCu Nanotubes with Highly Active Rh3Cu1 Alloy Phase for Overall Water Splitting in All pH Values

The combination of precious metals with non‐noble metals is an effective way to develop highly efficient, stable, and low cost electrocatalysts for overall water splitting. Herein, RhCu nanotubes (NTs) with rich structural defects are successfully synthesized by a mixed‐solvent strategy, which display superior activity and excellent stability for both the hydrogen evolution reaction (HER) and oxygen evolution reaction in all pH values. In particular, it only needs 8, 12, and 57 mV to deliver the current density of 10 mA cm^?2 for HER in alkaline, acidic, and neutral conditions, respectively. Experiments combined with density functional theory (DFT) calculations reveal that the exposure of a suitable composition of a highly active Rh₃Cu₁ alloy phase through acid etching is the key to improve electrocatalytic performance, since it weakens the adsorption free energy of atomic oxygen and hydrogen, as well as facilitating the dissociation of water molecules. In addition, the structural defects can also boost the catalytic performance because the adsorption of reactants can be largely enhanced. The results provide a simple method to prepare alloy NTs as highly efficient electrocatalysts for overall water splitting in all pH values.     

H2‐Directing Strategy on In Situ Synthesis of Co‐MoS2 with Highly Expanded Interlayer for Elegant HER Activity and its Mechanism

MoS₂ has drawn great attention as a promising Pt‐substituting catalyst for the hydrogen evolution reaction (HER). This work utilizes H₂ as the structure directing agent (SDA) to in situ synthesize a range of Co‐MoS₂‐n (n = 0, 0.5, 1.0, 1.4, 2.0) with expanded interlayer spacings (d = 9.2 – 11.1 Å), which significantly boost their HER activities. The Co‐MoS₂‐1.4 with an interlayer spacing of 10.3 Å presents an extremely low overpotential of 56 mV (at 10 mA cm^?2) and a Tafel slope of 32 mV dec^?1, which is superior than most reported MoS₂‐based catalysts. Density function theory calculations are used to gain insights that i) the H₂ can be dissociatively adsorbed on MoS₂ and greatly affect the related surface free energy by regulating the interlayer spacing; ii) the expanded interlayer spacing can significantly decrease the absolute value of ΔG_H, thereby leading to greatly promoted HER activity. Additionally, the large amounts of 1T phase (73.9–79.2%) and Co‐Mo‐S active sites (40.9–91.3%) also contribute to the enhanced HER activity of the synthesized samples. Overall, a simple new strategy for in situ synthesis of Co‐MoS₂ with an expanded interlayer spacing is proposed, which sheds light on other 2D energy material designs.     

Dual‐Functional N Dopants in Edges and Basal Plane of MoS2 Nanosheets Toward Efficient and Durable Hydrogen Evolution

Herein, the authors explicitly reveal the dual‐functions of N dopants in molybdenum disulfide (MoS₂) catalyst through a combined experimental and first‐principles approach. The authors achieve an economical, ecofriendly, and most efficient MoS₂‐based hydrogen evolution reaction (HER) catalyst of N‐doped MoS₂ nanosheets, exhibiting an onset overpotential of 35 mV, an overpotential of 121 mV at 100 mA cm^?2 and a Tafel slope of 41 mV dec^?1. The dual‐functions of N dopants are (1) activating the HER catalytic activity of MoS₂ S‐edge and (2) enhancing the conductivity of MoS₂ basal plane to promote rapid charge transfer. Comprehensive electrochemical measurements prove that both the amount of active HER sites and the conductivity of N‐doped MoS₂ increase as a result of doping N. Systematic first‐principles calculations identify the active HER sites in N‐doped MoS₂ edges and also illustrate the conducting charges spreading over N‐doped basal plane induced by strong Mo 3d –S 2p –N 2p hybridizations at Fermi level. The experimental and theoretical research on the efficient HER catalysis of N‐doped MoS₂ nanosheets possesses great potential for future sustainable hydrogen production via water electrolysis and will stimulate further development on nonmetal‐doped MoS₂ systems to bring about novel high‐performance HER catalysts.     

Engineering Multifunctional Collaborative Catalytic Interface Enabling Efficient Hydrogen Evolution in All pH Range and Seawater

Developing electrocatalysts with high compatibility to the reaction systems with complicated chemical properties represents an important frontier of catalyst design. Herein, a strategy by engineering a multifunctional collaborative catalytic interface to propel the hydrogen evolution reaction (HER) in the full pH range and seawater is reported. Collaborative catalytic interfaces among MXene, bimetallic carbide, and hybridized carbon are demonstrated to afford overall enhancement in electrical conductivity, exposure of reactive sites, water dissociation kinetics, H⁺/water adsorption, and intermediate H binding capability, which satisfy highly variable chemical environment for HER under different pH conditions. Therefore, the HER performance of resultant electrocatalysts can compete with commercial Pt/C in 0.5 m H₂SO₄ or 1.0 m KOH but outperform it under pH 2.2–11.2. They also show exceptional performance for HER in natural seawater with stringent requirements in catalytic activity and stability, exhibiting the best combination of Pt‐like activity, long durability (225 h, 64 times that of Pt/C), and 98% Faradaic efficiency, comparable with commercial Pt/C and the best documented electrocatalysts by far. This work may shed fresh light into the design of effective electrocatalytic interface for regulating the energy chemistry over wide operation conditions, and also inspires the exploration of hydrogen energy utilization technologies and beyond.     

A Monodisperse Rh2P‐Based Electrocatalyst for Highly Efficient and pH‐Universal Hydrogen Evolution Reaction

The search for Pt‐free electrocatalysts exceeding pH‐universal hydrogen evolution reaction (HER) activities when compared to the state‐of‐the‐art commercial Pt/C is highly desirable for the development of renewable energy conversion systems but still remains a huge challenge. Here a colloidal synthesis of monodisperse Rh₂P nanoparticles with an average size of 2.8 nm and their superior catalytic activities for pH‐universal HER are reported. Significantly, the Rh₂P catalyst displays remarkable HER performance with overpotentials of 14, 30, and 38 mV to achieve 10 mA cm^?2 in 0.5 m H₂SO₄, 1.0 m KOH, and 1.0 m phosphate‐buffered saline, respectively, exceeding almost all the documented electrocatalysts, including the commercial 20 wt% Pt/C. Density functional theory calculations reveal that the introduction of P into Rh can weaken the H adsorption strength of Rh₂P to nearly zero, beneficial for boosting HER performance.     

Ultralow Ru Loading Transition Metal Phosphides as High‐Efficient Bifunctional Electrocatalyst for a Solar‐to‐Hydrogen Generation System

Water splitting is a promising technology for sustainable conversion of hydrogen energy. The rational design of oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) bifunctional electrocatalysts with superior activity and stability in the same electrolyte is the key to promoting their large‐scale applications. Herein, an ultralow Ru (1.08 wt%) transition metal phosphide on nickel foam (Ru–MnFeP/NF) derived from Prussian blue analogue, that effectively drivies both the OER and the HER in 1 m KOH, is reported. To reach 20 mA cm^?2 for OER and 10 mA cm^?2 for HER, the Ru–MnFeP/NF electrode only requires overpotentials of 191 and 35 mV, respectively. Such high electrocatalytic activity exceeds most transition metal phosphides for the OER and the HER, and even reaches Pt‐like HER electrocatalytic levels. Accordingly, it significantly accelerates full water splitting at 10 mA cm^?2 with 1.470 V, which outperforms that of the integrated RuO₂ and Pt/C couple electrode (1.560 V). In addition, the extremely long operational stability (50 h) and the successful demonstration of a solar‐to‐hydrogen generation system through full water splitting provide more flexibility for large‐scale applications of Ru–MnFeP/NF catalysts.     

Highly Efficient Oxygen Evolution by a Thermocatalytic Process Cascaded Electrocatalysis Over Sulfur‐Treated Fe‐Based Metal–Organic‐Frameworks

The oxygen evolution reaction (OER) is a bottleneck process for water splitting and finding highly efficient, durable, low‐cost, and earth‐abundant electrocatalysts is still a major challenge. Here a sulfur‐treated Fe‐based metal–organic‐framework is reported as a promising electrocatalyst for the OER, which shows a low overpotential of 218 mV at the current density of 10 mA cm^?2 and exhibits a very low Tafel slope of 36.2 mV dec^?1 at room temperature. It can work on high current densities of 500 and 1000 mA cm^?2 at low overpotentials of 298 and 330 mV, respectively, by keeping 97% of its initial activity after 100 h. Notably, it can achieve 1000 mA cm^?2 at 296 mV with a good stability at 50 °C, fully fitting the requirements for large‐scale industrial water electrolysis. The high catalytic performance can be attributed to the thermocatalytic processes of H⁺ capture by –SO₃ groups from *OH or *OOH species, which cascades to the electrocatalytic pathway and then significantly reduces the OER overpotentials.     

Engineered MoSe2‐Based Heterostructures for Efficient Electrochemical Hydrogen Evolution Reaction

2D transition metal‐dichalcogenides are emerging as efficient and cost‐effective electrocatalysts for the hydrogen evolution reaction (HER). However, only the edge sites of their trigonal prismatic phase show HER‐electrocatalytic properties, while the basal plane, which is absent of defective/unsaturated sites, is inactive. Herein, the authors tackle the key challenge of increasing the number of electrocatalytic sites by designing and engineering heterostructures composed of single‐/few‐layer MoSe₂ flakes and carbon nanomaterials (graphene or single‐wall carbon nanotubes) produced by solution processing. The electrochemical coupling between the materials that comprise the heterostructure effectively enhances the HER‐electrocatalytic activity of the native MoSe₂ flakes. The optimization of the mass loading of MoSe₂ flakes and their electrode assembly via monolithic heterostructure stacking provides a cathodic current density of 10 mA cm^?2 at overpotential of 100 mV, a Tafel slope of 63 mV dec^?1, and an exchange current density (j₀) of 0.203 µA cm^?2. In addition, thermal and chemical treatments are exploited to texturize the basal planes of the MoSe₂ flakes (through Se‐vacancies creation) and to achieve in situ semiconducting‐to‐metallic phase conversion, respectively, thus they activate new HER‐electrocatalytic sites. The as‐engineered electrodes show a 4.8‐fold enhancement of j₀ and a decrease in the Tafel slope to 54 mV dec^?1.     

Multifunctional Single‐Crystallized Carbonate Hydroxides as Highly Efficient Electrocatalyst for Full Water splitting

The controllable synthesis of single‐crystallized iron‐cobalt carbonate hydroxide nanosheets array on 3D conductive Ni foam (FCCH/NF) as a monolithic oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) bifunctional electrocatalyst for full water splitting is described. The results demonstrate that the incorporation of Fe can effectively tune the morphology, composition, electronic structure, and electrochemical active surface area of the electrocatalysts, thus greatly enhancing the intrinsic electrocatalytic activity. The optimal electrocatalyst (F_0.25C₁CH/NF) can deliver 10 and 1000 mA cm^?2 at very small overpotentials of 77 and 256 mV for HER and 228 and 308 mV for OER in 1.0 m KOH without significant interference from gas evolution. The F_0.25C₁CH‐based two‐electrode alkaline water electrolyzer only requires cell voltages of 1.45 and 1.52 V to achieve current densities of 10 and 500 mA cm^?2. The results demonstrate that such fascinating electrocatalytic activity can be ascribed to the increase in the catalytic active surface area, facilitated electron and mass transport properties, and the synergistic interactions because of the incorporation of Fe.