Robust Bifunctional Electrocatalyst Research Articles

Bifunctional ligand Co metal-organic framework derived heterostructured Co-based nanocomposites as oxygen electrocatalysts toward rechargeable zinc-air batteries

Rational construction of efficient and robust bifunctional oxygen electrocatalysts is key but challenging for the widespread application of rechargeable zinc-air batteries (ZABs). Herein, bifunctional ligand Co metal–organic frameworks were first explored to fabricate a hybrid of heterostructured CoOx/Co nanoparticles anchored on a carbon substrate rich in CoNx sites (CoOx/Co@CoNC) via a one-step pyrolysis method. Such a unique heterostructure provides abundant CoNx and CoOx/Co active sites to drive oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), respectively. Besides, their positive synergies facilitate electron transfer and optimize charge/mass transportation. Consequently, the obtained CoOx/Co@CoNC exhibits a superior ORR activity with a higher half-wave potential of 0.88 V than Pt/C (0.83 V vs. RHE), and a comparable OER performance with an overpotential of 346 mV at 10 mA cm−2 to the commercial RuO2. The assembled ZAB using CoOx/Co@CoNC as a cathode catalyst displays a maximum power density of 168.4 mW cm−2, and excellent charge–discharge cyclability over 250 h at 5 mA cm−2. This work highlights the great potential of heterostructures in oxygen electrocatalysis and provides a new pathway for designing efficient bifunctional oxygen catalysts toward rechargeable ZABs.

Architecting N-doped Carbon Nanotube-Rich Carbon Nanofibers with Biomimetic Vine-Leaf-Whisker Structure as Robust Bifunctional Electrocatalysts for Rechargeable Zn-Air Batteries.

Efficient and durable bifunctional catalysts toward oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are urgently desirable but challenging for rechargeable Zn-air batteries (ZABs), especially flexible wearable ZABs. Inspired by the vine-leaf-whisker structure in nature, we proposed a three-dimensional (3D) hierarchical bifunctional catalyst (denoted as Co-Fe-Zn@N-CNT/CNF) consisting of N-doped carbon nanotubes embedded with abundant CoFe alloy nanoparticles, leaf-shaped N-doped carbon nanoflakes, and porous carbon fibers for rechargeable ZABs. The special biomimetic structure provides a large specific surface area, allowing for high exposure of the active site and ensuring fast mass transport/charge transfer. The close combination of CoFe bimetallic alloys and N-doped carbon nanotubes delivers high electrocatalytic activity, while the coexistence of various active sites such as metal nanoparticles (NPs), metal-Nx, doped N species, and their synergistic interactions endows the catalysts with more active sites. As such, the Co-Fe-Zn@N-CNT/CNF catalyst achieves superior bifunctional catalytic activities for the ORR (a half-wave potential of 0.84 V) and the OER (an overpotential of 326 mV at 10 mA cm-2) in alkaline media, comparable to commercial Pt/C and RuO2. Remarkably, both aqueous and solid-state ZABs assembled with Co-Fe-Zn@N-CNT/CNF catalysts as air electrodes demonstrate excellent charging/discharging performance, high peak power density, and robust long-term cycling stability. More interestingly, the flexible ZAB performs well even under bending conditions, displaying satisfactory device stability and mechanical flexibility. This study presents a new collective morphological-composition-structural engineering strategy for exploiting the efficient bifunctional oxygen electrocatalysts, which is of great significance for high-performance rechargeable ZABs and wearable energy storage devices.

Durable Pulse-Electrodeposited Ni-Fe-S Nanosheets Supported on a Ni-S Three Dimensional Pattern as Robust Bifunctional Electrocatalysts for Hydrogen Evolution and Urea Oxidation Reactions.

This study aims to establish easy-to-fabricate and novel structures for the synthesis of highly active and enduring electrocatalysts for the hydrogen evolution reaction (HER) and urea oxidation reaction (UOR). Gradient electrodeposition and four different time regimes were utilized to synthesize Ni-S 3D patterns with the optimization of electrodeposition time. Pulse electrodeposition was employed for the synthesis of Ni-Fe-S nanosheets at three different frequencies and duty cycles to optimize the pulse electrodeposition parameters. The sample synthesized at 13 min of gradient electrodeposition with a 1 Hz frequency and 0.7 duty cycle for pulse electrodeposition demonstrated the best electrocatalytic performance. The optimized electrode further showed remarkable performance for HER and UOR reactions, requiring only 54 mV and 1.25 V to deliver 10 mA cm-2 for HER and UOR, respectively. Moreover, the overall cell voltage of the two-electrode system in 1 M KOH and 0.5 M urea was measured at 1.313 V, delivering 10 mA cm-2. Constructing Ni-Fe-S nanosheets on 3D Ni-S significantly increased the electrochemical surface area from 51 to 278 for the Ni-S and Ni-Fe-S layers. Tafel slopes were measured as 138 and 182 mV dec-1 for the HER and UOR for the Ni-S coating layer and 97 mV dec-1 for the HER and 131 mV dec-1 for the UOR for the optimal Ni-Fe-S nanosheets on Ni-S. Minimal changes in the potential were observed at 100 mA cm-2 in 50 h regarding the HER and UOR, signifying exceptional electrocatalytic stability. This study provides economically viable, highly active, and long-lasting electrocatalysts suitable for HER and UOR applications.

Synergistic Coupling of CoS2/MoS2 with Polypyrrole as a Highly Efficient and Robust Bifunctional Electrocatalyst for Water Splitting

Synergistic Coupling of CoS₂/MoS₂ with Polypyrrole as a Highly Efficient and Robust Bifunctional Electrocatalyst for Water Splitting

Multiscale Confinement Engineering for Boosting Overall Water Splitting by One-Step Stringing of a Single Atom and a Janus Nanoparticle within a Carbon Nanotube.

Enzyme-mimicking confined catalysis has attracted great interest in heterogeneous catalytic systems that can regulate the geometric or electronic structure of the active site and improve its performance. Herein, a liquid-assisted chemical vapor deposition (LCVD) strategy is proposed to simultaneously confine the single-atom Ru sites onto sidewalls and Janus Ni/NiO nanoparticles (NPs) at the apical nanocavities to thoroughly energize the N-doped carbon nanotube arrays (denoted as Ni/NiO@Ru-NC). The bifunctional Ni/NiO@Ru-NC electrocatalyst exhibits overpotentials of 88 and 261 mV for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) at 100 mA cm-2 in alkaline solution, respectively, all ranking the top tier among the carbon-supported metal-based electrocatalysts. Moreover, once integrated into an anion-exchange membrane water electrolysis (AEMWE) system, Ni/NiO@Ru-NC can act as an efficient and robust bifunctional electrocatalyst to operate stably for 50 h under 500 mA cm-2. Theoretical calculations and experimental exploration demonstrate that the confinement of Ru single atoms and Janus Ni/NiO NPs can regulate the electron distribution with strong orbital couplings to activate the NC nanotube from sidewall to top, thus boosting overall water splitting.

Immobilizing Bimetallic RuCo Nanoalloys on Few-Layered MXene as a Robust Bifunctional Electrocatalyst for Overall Water Splitting.

Doping Co atoms into Ru lattices can tune the electronic structure of active sites, and the conductive MXene can adjust the electrical conductivity of catalysts, which are both favorable for improving the electrocatalytic activity of the catalyst for water splitting. Here, ruthenium-cobalt bimetallic nanoalloys coupled with exfoliated Ti3 C2 Tx MXene (RuCo-Ti3 C2 Tx ) have been constructed by ice-templated and thermal activation. Due to the strong interaction between the RuCo nanoalloys and conductive MXene, RuCo-Ti3 C2 Tx not only exhibits an excellent hydrogen evolution reaction (HER) performance with a low overpotential and Tafel slope (60 mV, 34.8 mV dec-1 in 0.5 M H2 SO4 and 52 mV, 38.7 mV dec-1 in 1 M KOH), but also good oxygen evolution reaction (OER) performance in an alkaline electrolyte (266 mV, 111.1 mV dec-1 in 1 M KOH). The assembled RuCo-Ti3 C2 Tx ||RuCo-Ti3 C2 Tx electrolyzer requires a lower potential (1.56 V) than does the Pt/C||RuO2 electrolyzer at 10 mA cm-2 . A boosted catalytic HER activity from immobilizing the RuCo nanoalloys on MXene was unveiled by density functional theory calculations. This study provides a feasible and efficient strategy for developing MXene-based catalysts for overall water splitting.

Lignin‐assisted alloying engineering of CoNiRu trimetallic nano‐catalyst for effective overall water splitting

AbstractThe development of inexpensive and robust bifunctional electrocatalysts for hydrogen evolution reactions (HER) and oxygen evolution reactions (OER) was crucial for renewable energy systems. Herein, a novel strategy for preparing CoNiRu alloy nano‐electrocatalyst capsulated by nitrogen‐doped biochar (CoNiRu@NLC) using carboxymethylated lignin macromolecules was proposed. CoNiRu@NLC exhibited excellent HER and OER performance, and the overall water splitting voltage was only 1.47 V at 10 mA/cm2 with excellent catalytic stability, which was superior to the noble metal catalysts Pt/C ‖ RuO2. Theoretical calculations confirmed the strong electron interaction between CoNiRu alloy and carbon layer, and XPS patterns proved that the electrons transfer from Ru to CoNi, significantly boosted the electrocatalytic activity. This study demonstrated the importance of lignin‐driven alloying on enhancing catalytic performance and provided a concept for the development of high‐efficiency catalysts and high‐value utilization of polyphenol biomass.

Self-supporting hierarchical Co3O4-nanowires@NiO-nanosheets core-shell nanostructure on carbon foam to form efficient bifunctional electrocatalyst for overall water splitting

Designing cost-effective and robust bifunctional electrocatalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is highly desired in hydrogen production from overall water splitting, but still suffers great challenges due to the sluggish catalytic OER/HER kinetics. In this paper, a surface/defect engineering strategy is developed to synthesize three-dimensional (3D) carbon foam (CF)-supported unique hierarchical Co3O4 nanowires@NiO nanosheets core–shell nanostructured catalyst (NiO@Co3O4/CF) with rich oxygen-vacancies as a novel bifunctional catalyst for alkaline water splitting electrolysis. Benefited from the synergy of the 3D hierarchical core–shell structure and rich oxygen vacancies, the as-obtained NiO@Co3O4/CF shows both excellent OER (η200 = 325 mV, η500 = 374 mV) and HER (η10 = 104 mV) activities with low Tafel slopes (64.26 mV dec−1 for OER and 109.14 mV dec−1 for HER, respectively) and outstanding stability. A simple overall water splitting electrolysis cell assembled by this bifunctional NiO@Co3O4/CF as both OER and HER catalysts requires only a cell voltage of 1.53 V to obtain the current density of 10 mA cm−2 and displays a long-term stability. This work has successfully developed an approach for rational design and novel synthesis of metal oxide hybrids as bifunctional electrocatalysts with high activity and stability for overall water splitting.

Facile Synthesis of Vertical Layered Double Hydroxides Nanosheets on Co@Carbon Nanoframes as Robust Bifunctional Oxygen Electrocatalysts for Rechargeable Zn–Air Batteries

The development of efficient and low‐cost bifunctional catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is imperative but remains challenging in rechargeable zinc–air batteries. Herein, a metal oxidation‐assisted approach is developed for the facile synthesis of a highly efficient bifunctional catalyst (Co@NC@LDHs) which is composed of layered double hydroxides (LDHs) nanosheets in situ vertically grown on the surface of hollow carbon nanoframes encapsulating Co nanoparticles (Co@NC). Specifically, the vertical LDHs distributing on the carbon surface ensure the maximized number of accessible active sites and the interaction between LDHs with the carbon matrix. The hierarchically structured bifunctional Co@NC@LDHs display an overpotential of 0.33 V at 10 mA cm−2 for OER and a half‐wave potential of 0.88 V for ORR. The potential gap (ΔE) of Co@NC@LDHs is calculated to be 0.68 V, outperforming the mixed Pt/C + RuO2 catalysts (ΔE = 0.77 V), manifesting its superior bifunctional electrocatalysis performance. Moreover, the Zn–air batteries based on Co@NC@LDHs electrocatalyst exhibit a high peak power density (185.2 mW cm−2) and excellent durability (5.0 mA cm−2 over 500 h). This work may provide a facile strategy for the fabrication of LDHs on carbon substrate, acting as efficient catalysts for broad energy‐related applications.

Flower-shaped disorderly nickel-iron nitride nanosheets as a robust bifunctional electrocatalyst for overall water splitting

Developing highly efficient bifunctional transition metal-based electrocatalysts is important for reducing the practical costs of water splitting. Herein, we present a flower-shaped disorderly nickel-iron nitride nanosheets bifunctional electrocatalysts (NiFeNx/NF), which was prepared in situ on a nickel foam substrate using a hydrothermal and thermal ammonia-reduction method. The unique structure of the flower-shaped disorderly nanosheets increases the amount of electrocatalytic active sites and promotes efficiency of both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) by facilitating charge and mass transfer. The bifunctional catalyst demonstrated exceptional performance with overpotentials of only 78 mV for HER and 280 mV for OER at current densities of 10 mA cm−2 and 100 mA cm−2, respectively. Additionally, the NiFeNx/NF exhibited outstanding stability, achieving a cell voltage of only 1.53 V for overall water splitting at 10 mA cm−2 in 1.0 M KOH, and continuously operated for 90 h at 20 mA cm−2 without significant voltage increase. These findings contribute to the development of high-performance, cost-effective, and environmentally friendly bifunctional catalysts based on transition metals for water splitting.

Three-Dimensional Sm-Doped NiCu-LDH on Ni Foam as a Highly Robust Bifunctional Electrocatalyst for Total Water Splitting

Three-Dimensional Sm-Doped NiCu-LDH on Ni Foam as a Highly Robust Bifunctional Electrocatalyst for Total Water Splitting

Engineering charge redistribution on high-density RuCo nanoclusters loaded on N-doped graphite carbon as robust bifunctional oxygen electrocatalysts for rechargeable Zn-air batteries

A major challenge for the development of rechargeable Zn-air batteries (ZABs) is represented by the lack of effective bifunctional electrocatalysts for the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). In this work, a high-density alloy nanocluster catalyst evenly loaded on N-doped porous sheet-like graphite carbon layer arrays (RuCo/NC) was fabricated by one-step electrochemical exfoliation, accelerating the active site exposure and mass transfer. RuCo/NC exhibited a lower reversible oxygen overpotential of 0.713 V for the OER / ORR compared to the benchmark Pt/C//RuO2 (0.755 V). Moreover, density functional theory (DFT) calculations revealed an optimized adsorption / desorption behavior of *OOH, *OH, and *O species caused by the charge redistribution between Ru and Co in RuCo/NC, which dramatically lowered the reaction energy barrier for the rate-limiting steps in ORR / OER. A home-assembled ZAB with a RuCo/NC air electrode catalyst exhibited a higher open-circuit voltage (OCV) of 1.422 V and a power density of 130 mW cm−2, exceeding those of Pt/C//RuO2 (OCV = 1.348 V, power density = 108 mW cm−2). This work introduces a promising method for fabricating hierarchical sheet-like carbon-based functional materials with potential application in fuel cells and water electrolysis.

NiFeP composites supported on Ni foam as an efficient and robust bifunctional electrocatalyst for overall water splitting in alkaline solution

Developing high-efficiency and cost-effective bifunctional electrocatalysts for overall water splitting is crucial for the utilization of hydrogen energy. In this work, NiFeP composites supported on Ni foam were prepared by a mild, wet chemical method followed by an in situ phosphorization process. The as-prepared NiFeP/NF exhibits high electrocatalytic activity in hydrogen and oxygen evolution reactions, which should be attributed to the unique heterostructures in the NiFeP composite. When used as a bifunctional catalyst for overall water splitting in an alkaline solution, a long-term duration of 1100 h has been achieved under a current density of 300 mA cm−2. Such good performance makes the composite a promising electrocatalyst and ranks it among the best catalysts reported recently for overall water splitting under alkaline conditions. Notably, the preparation of NiFeP/NF can be accomplished without complicated reaction conditions and using expensive instruments, which enables great potential for large-scale application.

2D Ni-organic frameworks decorated carbon nanotubes encapsulated Ni nanoparticles for robust C[sbnd]N and H[sbnd]O bonds cleavage

In this work, we report a robust bifunctional electrocatalyst composed of 2D Ni- organic frameworks (Ni-MOF) and nitrogen doped carbon nanotubes encapsulated Ni nanoparticles (Ni-MOF@Ni-NCNT) for CN and HO bonds dissociation. Due to the presence of Ni-NCNT, adsorption of OH– species is enhanced and CO2 binding strength is simultaneously weakened leading to a boosted urea oxidation reaction performance reflected by decrement in potential at 100 mA cm−2 by 69 mV. The loosened binding strength with CO2 specie is highlighted by in-situ electrochemical impedance spectroscopy (EIS) test and DFT calculation. Moreover, the alkaline hydrogen evolution reaction (HER) performance of Ni-MOF@Ni-NCNT is better than Ni-MOF and Ni-NCNT evidenced by the overpotential at 50 mA cm−2 decreased by 224 mV and 900 mV ascribed to the synergistic effect, in which Ni-MOF, Ni nanoparticles and Ni-Nx-C facilitates water adsorption, dissociation and adsorption/combination of hydrogen ions, respectively. The assembled HER- urea oxidation reaction (UOR) system requires only 1.33 V to reach 10 mA cm−2, 70 mV lower than water splitting driven by Pt/C-IrO2.

Synthesis of CuMoS micro‐rods material as efficient bifunctional electrocatalyst for overall water splitting

AbstractIn oxygen evolution reactions (OER) metal sulfides are the subject of extensive research. Copper‐molybdenum sulfides (CuMoS) that can be made a simple hydrothermal treatment are designed to reduce catalyst costs even more. Here, we demonstrate that binder free electrode composed of micro‐rod structure copper‐molybdenum sulfides on nickel foam (CuMoS/NF) can be employed as an active and robust bifunctional electrocatalyst for water splitting. CuMoS/NF catalyst displays an overpotential for OER of 358 mV (121 mV dec−1) and HER of 129 mV (101 mV dec−1) at current density of 10 mA cm−2. CuMoS/NF is stable for 60 hours with potential deviations in OER and HER of 2.8 % and 3.2 %, respectively. The active bifunctional CuMoS/NF electrode combination helps to fabricate a water electrolyser with 10 mA cm−2 current density at 1.65 V. CuMoS/NF//CuMoS/NF shows good stability over 60 hours with a potential deviation of 2.7 %. The earth‘s abundant non‐precious metal‐based electrode, and solar cell delivered continuous hydrogen and oxygen (1.65 V), making it possible to produce a significant quantity of hydrogen at a low‐cost and on a large‐scale.

Promoting High-Oxidation-State Metal Active Sites in a Hollow Ternary Metal Fluoride Nanoflake Array for Urea Electrolysis.

The adsorption ability of hydrogen, hydroxide, and oxygenic intermediates plays a crucial role in electrochemical water splitting. Electron-deficient metal-active sites can prompt electrocatalytic activity by improving the adsorption ability of intermediates. However, it remains a significant challenge to synthesize highly abundant and stable electron-deficient metal-active site electrocatalysts. Herein, we present a general approach to synthesizing a hollow ternary metal fluoride (FeCoNiF2) nanoflake array as an efficient and robust bifunctional electrocatalyst for the hydrogen evolution reaction (HER) and urea oxidation reaction (UOR). We find that the F anion withdraws electrons from the metal centers, inducing an electron-deficient metal center catalyst. The rationally designed hollow nanoflake array exhibits the overpotential of 30 mV for HER and 130 mV for UOR at a current density of 10 mA cm-2 and superior stability without decay events over 150 h at a large current density of up to 100 mA cm-2. Remarkably, the assembled urea electrolyzer using a bifunctional hollow FeCoNiF2 nanoflake array catalyst requires cell voltages of only 1.352 and 1.703 V to afford current densities of 10 and 100 mA cm-2, respectively, which are 116 mV less compared with that required for overall water splitting.

Spatially confined sub-nanometer Pt in RuO2 nanosheet as robust bifunctional oxygen electrocatalyst for stabilizing Li-O2 batteries

Developing a highly active and durable bifunctional oxygen catalyst is the key to boosting lithium-oxygen batteries, but it remains a grand challenge. Herein, we demonstrate a remarkably active and durable bifunctional electrocatalyst (Pt/RuO2/G) with highly exposed active sites for stabilizing Li-O2 batteries by synergistically coupling the advanced oxygen reduction reaction (ORR) catalyst Pt with the oxygen evolution reaction (OER) catalyst RuO2, strongly anchored on graphene. The combined merits, including 2D porous morphology, ultrathin thickness (∼2.5 nm), and a well-dominated (110) plane of ultrasmall RuO2, originating from the efficient spatial confinement, provide the bifunctional Pt/RuO2/G electrocatalyst an extremely narrow OER/ORR voltage gap of only 0.633 V. Moreover, the as-designed Pt/RuO2/G-based Li-O2 batteries deliver a low initial charge-discharge mid-capacity overpotential (0.78 V) and remarkable lifetime (2,200 h) at 200 mA g−1, outperforming most Ru-based catalysts for Li-O2 batteries. This work provides a reliable practical approach for high-performance Li-O2 batteries.

Bimetallic 3D hollow-nanoshell FeCo-oxynitride/N and S co-doped carbon nanotubes as a robust bifunctional oxygen electrocatalyst for rechargeable Zn-air batteries

Bimetallic 3D hollow-nanoshell FeCo-oxynitride/N and S co-doped carbon nanotubes as a robust bifunctional oxygen electrocatalyst for rechargeable Zn-air batteries

Interface engineering assisted Fe-Ni3S2/Ni2P heterostructure as a high-performance bifunctional electrocatalyst for OER and HER

Rational development and construction of electrochemical water splitting catalysts with excellent activity and super-durability utilizing earth-abundant elements are extremely desirable and imperative for energy crisis. Herein, a self-supported hierarchical Fe-doped nickel sulfide/nickel phosphide (nanoflower-linked nanosheet arrays grown vertically on nickel foam) heterostructure electrocatalyst was obtained via a successive structural transformation to realize high-efficiency alkaline OER and HER performance. Benefiting from the novel nanoflower-sheet crosslinked structure on NF, electronic coupling reconstruction and abundant edge sites, as-synthesized Fe-Ni3S2/Ni2P electrocatalyst exhibits remarkable electrocatalytic OER and HER activity in both low and high current density regions. Specifically, the Fe-Ni3S2/Ni2P electrode achieved low overpotentials of 172, 277 and 357 mV at current densities of 10, 50 and 100 mA·cm−2 for OER, respectively. A series of experimental results confirmed that the surface reconfiguration behavior of Fe-Ni3S2/Ni2P heterostructure led to the formation of amorphous M-OH bond system, which was answerable to the prominent OER catalyst properties. This work confirms the potential of designing robust bifunctional electrocatalysts for alkaline water electrocatalysis by carefully combining doping engineering as well as interfacial effects.

Cd doped Ni3S2 nanosheet arrays grown on nickel foam as highly efficient and robust bifunctional electrocatalysts for alkaline overall water splitting

Stable and highly efficient electrocatalysts are very important for water splitting. Introducing exogenous elements can alter the structure of the catalysts, thus improving the electrocatalytic activity. In this study, via a facile hydrothermal strategy and Cd/Ni ratio tuning, Cd-doped Ni3S2 nanosheet arrays grown on Ni foam (Cd-Ni3S2/NF-x) are fabricated. The optimized Cd-Ni3S2/NF-1/4 exhibits the best electrocatalytic performance in alkaline media (1 M KOH) due to the higher electroconductivity and more accessible active sites. At a current density of 10 mA cm-2, ultralow overpotentials of 140 and 197 mV are required for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively. During overall water splitting, a two-electrode electrolyzer of Cd-Ni3S2/NF-1/4 was used to achieve a low cell voltage of 1.54 V with ultralong-term durability ≥ 50 h. Introducing Cd into Ni3S2 leads to Ni→S electron transfer, thus increasing the Ni3+ content, which is beneficial to the increased OER activity. Density functional theory (DFT) calculations demonstrate that Cd-doped Ni3S2 has a reduced Gibbs free energy of hydrogen adsorption (∆GH*) in the HER and a decreased energy barrier of rate determination in the OER, contributing to the improved overall water-spitting performance. This work offers an effective strategy by virtue of element doping to fabricate highly effective bifunctional electrocatalysts to realize mass production of hydrogen.