Non-noble Transition Metal Research Articles

Biology-Based Synthesis of Nickel Single Atoms on the Surface of Geobacter sulfurreducens as an Efficient Electrocatalyst for Alkaline Water Electrolysis.

Single-atom metal catalysts are promising electrocatalysts for water electrolysis. Nickel-based electrocatalysts have shown attractive application prospects for water electrolysis. However, synthesizing stable Ni single atoms using chemical and physical approaches remains a practical challenge. Here, a facile and precise method for synthesizing stable nickel single atoms on the surface of Geobacter sulfurreducens using a microbial-mediated extracellular electron transfer (EET) process is demonstrated. It is shown that G. sulfurreducens can effectively anchor nickel single atoms on their surface. X-ray absorption near-edge structure and Fourier-transformed extended X-ray absorption fine structure spectroscopy confirm that the nickel single atom is coordinated to nitrogen in the cytochromes. The as-synthesized nickel single atoms on G. sulfurreducens exhibit excellent bifunctional catalytic properties for alkaline water electrolysis with low overpotential (η) to achieve current density (10mAcm-2) for both hydrogen evolution reactions (η = 80mV) and oxygen evolution reaction (η = 330mV) with minimal catalyst loading of 0.0015mgNicm-2. The nickel single-atom catalyst shows long-term stability at a constant electrode potential. This synthesis method based on the EET capability of electroactive bacteria provides a simple and scalable approach for producing low-cost and highly efficient nonnoble transition metal single-atom catalysts for practical applications.

Single-, double-, and triple-atom catalysts on PC6 for nitrate reduction to ammonia: A computational screening

Single-atom catalysts (SACs) exhibit higher atomic utilization, while double-atom catalysts (DACs) and triple-atom catalysts (TACs) have an advantage due to the synergistic effect of multiple atomic centers. However, the current research on the mechanism of multiple-atom catalysts in electrocatalytic nitrate reduction to ammonia (NRA) remains insufficient. Herein, we investigated a series of homonuclear single-, double-, and triple-atom catalysts on carbon phosphide (PC6) monolayers (TMn@PC6, where TM = non-noble transition metals; n = 1, 2, or 3). The NRA activity of these catalysts was assessed by the density functional theory calculations, Co3@PC6 and Ru3@PC6 exhibit superior limiting potentials of −0.34 V and −0.36 V, respectively. Their capability to produce *H with optimal free energy on their surface enhances the electrochemical potential-determining step of *NO to *NOH while simultaneously inhibiting the hydrogen evolution reaction. The movement of the d-band center, induced by metal atom doping, regulates the adsorption strength of *NO, thus achieving a lower barrier for the hydrogenation step. This work provides theoretical guidance for the development of highly efficient multiple-atom catalysts for NRA.

Single-atom nickel on defective g-C4N3 as a promising bifunctional electrocatalyst for the OER and ORR: a first-principles analysis

Searching for inexpensive and highly active materials to replace noble metals for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is an important challenge. The two-dimensional semi-metallic carbon nitride g-C4N3 is an excellent candidate for electrochemical reactions owing to its eminent conductivity and stability. Here, using density functional theory (DFT) a series of low-budget non-noble transition metal single-atom (SAC) loaded on the g-C4N3 (named as TM@C4N3, TM = Cr, Mn, Fe, Co, Ni, Cu) were investigated as electrocatalysts for OER and ORR. Ni@C4N3 shows an enormous application potential as electrode material, with OER and ORR overpotentials of 0.59 V and 0.23 V, respectively. The second lowest binding energy between Ni and support g-C4N3 indicates that Ni@C4N3 possesses good overall stability. The d-band center as well as metal valence as the descriptor exhibit good agreement with the adsorption energy of the intermediate. A linear relationship exists among the adsorption energies of the three intermediates O, OH, and OOH, given the similarity that they are all bonded to the metal through one oxygen atom. By adjusting the adsorption energy of these intermediates, the catalytic activity of electrocatalysts can be tuned for OER and ORR. This study confirmed that Ni@C4N3 is a good bifunctional catalyst and provides important guidance for the design of bifunctional electrocatalysts for OER and ORR.

Understanding Advanced Transition Metal-Based Two Electron Oxygen Reduction Electrocatalysts from the Perspective of Phase Engineering.

Non-noble transition metal (TM)-based compounds have recently become a focal point of extensive research interest as electrocatalysts for the two electron oxygen reduction (2e- ORR) process. To efficiently drive this reaction, these TM-based electrocatalysts must bear unique physiochemical properties, which are strongly dependent on their phase structures. Consequently, adopting engineering strategies toward the phase structure has emerged as a cutting-edge scientific pursuit, crucial for achieving high activity, selectivity, and stability in the electrocatalytic process. This comprehensive review addresses the intricate field of phase engineering applied to non-noble TM-based compounds for 2e- ORR. First, the connotation of phase engineering and fundamental concepts related to oxygen reduction kinetics and thermodynamics are succinctly elucidated. Subsequently, the focus shifts to a detailed discussion of various phase engineering approaches, including elemental doping, defect creation, heterostructure construction, coordination tuning, crystalline design, and polymorphic transformation to boost or revive the 2e- ORR performance (selectivity, activity, and stability) of TM-based catalysts, accompanied by an insightful exploration of the phase-performance correlation. Finally, the review proposes fresh perspectives on the current challenges and opportunities in this burgeoning field, together with several critical research directions for the future development of non-noble TM-based electrocatalysts.

ReS2/CoS heterostructure catalysts for electrochemical application in hydrogen evolution and supercapacitor

Development of Nano-heterostructures based on transition metal chalcogenides is promising strategy to accelerate the catalytic performance for hydrogen evolution reaction (HER) and supercapacitor application. The design and development of non-noble transition metal based catalysts is required for the low-cost, efficient and earth-abundant electrodes for sustainable energy conversion and storage. ReS2/CoS heterostructures were synthesized by two step methods involving liquid phase exfoliation of ReS2 and hydrothermal decoration of CoS. The prepared ReS2/CoS heterostructures shows high performance supercapacitor applications with specific capacitance of 663.2 F/g at 2 A/g and 643.1 F/g at scan rate 5 mV/s, showing enhanced redox reaction and number of electrochemically active sites due to synergistic effect and modulated electronic structure. Additionally, ReS2/CoS heterostructures shows the superior HER performance in alkaline condition with overpotential of 187 mV at 10 mA/cm2 due to accelerated kinetics, enhanced ECSA and low charge transfer resistance. The ReS2/CoS heterostructures shows the stable electrochemical performance for HER for more than 17 h.

Efficient alkaline water electrolysis with an iron-incorporated yttrium oxide/yttrium phosphide nanorod catalyst on Ni foam: overpotential reduction and electrochemical insights

Production of a non-noble transition metal phosphide-based catalyst containing Fe, Y, P, and O for bifunctional water-splitting applications.

Efficient C-N coupling for urea electrosynthesis on defective Co3O4 with dual-functional sites.

Urea electrosynthesis under ambient conditions is emerging as a promising alternative to conventional synthetic protocols. However, the weak binding of reactants/intermediates on the catalyst surface induces multiple competing pathways, hindering efficient urea production. Herein, we report the synthesis of defective Co3O4 catalysts that integrate dual-functional sites for urea production from CO2 and nitrite. Regulating the reactant adsorption capacity on defective Co3O4 catalysts can efficiently control the competing reaction pathways. The urea yield rate of 3361 mg h-1 gcat-1 was achieved with a corresponding faradaic efficiency (FE) of 26.3% and 100% carbon selectivity at a potential of -0.7 V vs. the reversible hydrogen electrode. Both experimental and theoretical investigations reveal that the introduction of oxygen vacancies efficiently triggers the formation of well-matched adsorption/activation sites, optimizing the adsorption of reactants/intermediates while decreasing the C-N coupling reaction energy. This work offers new insights into the development of dual-functional catalysts based on non-noble transition metal oxides with oxygen vacancies, enabling the efficient electrosynthesis of essential C-N fine chemicals.

Assessing the Stability of Co3O4 Under Oxygen Evolution Reaction Conditions at Low and Mild pH

Water and CO2 electrolysis will play a crucial role in converting renewable energy into value-added chemicals and chemical fuels. To successfully employ and expand these technologies globally, ideally, one should develop Earth-abundant, cost-effective catalysts with high activity and stability. The requirements for the catalysts depend on the configuration of the electrolyzer, and the electrolyte used there. However, especially in CO2 electrolysis, the stability of the catalyst in a certain electrolyte does not guarantee its successful use on a long-term scale, as the pH in the electrolyzer may change during long-term experiments due to ion transfer through the membrane.1 The anode materials should, therefore, be stable across a broad pH range and/or in carbonate-rich electrolytes. Although the earth-abundant, non-noble transition metals, and their compounds are highly stable at higher pH, they are less stable than Ir or Pt at low and (near-)neutral pH.2 Interestingly, recent studies have shown that Co-based oxides exhibit promising stability even at low pH.3, 4 However, the nature of this stability as well as the mechanisms of non-noble metal oxides catalyzing OER at low or near-neutral pH, are yet to be discovered. In this work, we analyze the stability of cobalt oxide under various electrochemical conditions at low pH with the use of a scanning flow cell (SFC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) and differential electrochemical mass spectrometry (DEMS). By using these techniques, we can follow the dissolution of Co online and find potential narrow stability windows before and during the oxygen evolution reaction (OER). Benefiting from the obtained results, mitigating strategies for minimizing Co dissolution are proposed and discussed.

(Invited) Novel Strategies in the Design of the Oxygen Evolving Catalysts for Water Electrolysis

Hydrogen producing electrolytic water splitting is one of the most important electrochemical technologies supporting the de-fossilization of the society and enabling integration of renewable energy sources into electric grid. The water electrolysis in fact combines two electrocatalytic reactions – a two electron hydrogen evolution and four electron oxygen evolution, which in most cases represents the kinetically limiting process determining the efficiency of the green hydrogen production. Given the harsh conditions at which the oxygen evolution is driven in water electrolysers a design of practical oxygen evolving catalysts needs to reflect not only the intrinsic activity, but also stability and feasibility. To reflect these additional factors a specific challenges connected with the pH at which the intended water electrolysis ought to operate need to be included into catalyst design. The development of the anode materials for alkaline water electrolyzers faces less restrictions given reasonable stability of the non-noble transition metal oxides/oxihydroxides at operando conditions. The development of novel anode materials for polymer electrolyte water electrolyzers is far more challenging due the low stability of transition metals at OER potentials in acid media which restricts the available catalysts to those based on scarce Ru, or Mn.The presented paper will describe two approaches attempting development of novel OER catalysts for acid media. The first approach aims at following the high entropy concept pioneered theoretically by Svane and Rossmeisl [1]. The synergetic effects encountered in high entropy oxides will be demonstrated on mixed Ru-Ir pyrochlores stabilized by lanthanides prepared by spray freeze freeze drying technique. While the high entropy oxides are highly active in OER the need to explore noble metal oxides may still represent a stumbling block in large scale deployment. This restriction may be removed by targeted activation of wide band semiconducting oxides by simultaneous n- and p- co-doping [2]. The co-doping strategy alters the electronic structure of the host oxide generating a pseudo-band in the materials band gap facilitating an electrocatalytic activity (in dark). The concept predicts that a wide band semiconductors based on , e.g. Ti, may be activated into a active OER catalysts potentially compensating a lower intrinsic activity with low price. The potential of the approach will be demonstrated on two systems – co-doped anatase polymorph of TiO2 and on co-doped cubic titanate based perovskites.

Exceptional formaldehyde oxidation at room temperature on Co single-atom functionalized TiO2 nanowires via highly effective O2 activation

O2 activation is vital for catalyzing the oxidation of formaldehyde (HCHO). Despite the high O2 activation capabilities demonstrated by noble metal catalysts, their practical application is impeded by their exorbitant cost. Herein, Co single atoms were successfully incorporated into titanium dioxide nanowires (TiO2-NWs). Furthermore, the key step in the HCHO catalytic oxidation process was elucidated through in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS) and density functional theory (DFT) calculations. Finally, the intricate O2 activation mechanism was explored, revealing the catalyst’s exceptional performance in ambient HCHO oxidation. Notably, it outperformed commercial TiO2 (TiO2-P25) by 13.3 times and Co-supported TiO2-P25 by 1.9 times. Co single atoms facilitated the conversion of O2 into superoxide (O2-), significantly reducing the reaction barrier of dioxymethylene to formate. This superior O2 activation was attributed to the active nature and unsaturated electronic configuration of Co single atoms. This study provides a novel, cost-effective strategy for creating HCHO elimination catalysts with accessible nonnoble transition metals.

Rational Design of HighPerformance M-N-C Single Atom Catalysts

High-performance electrocatalysts are required because the sluggish kinetics of Oxygen Reduction Reaction (ORR) at the cathode in either Fuel Cell (FC) or Metal-Air Battery (MAB). The current most effective ORR catalysts are noble Pt-group metals, whose high price and low abundance severely hamper the widespread application of FC and MAB. Dispersively non-noble transition metal coordinated with nitrogen atoms doped in carbon nanomaterials (M-N-C) Single Atom Catalysts (SACs) have been considered as the most promising catalysts for the ORR. Here, the effect of typical morphology on the activity and stability of SACs was discussed firstly. Moreover, the effect of metal type, coordination nitrogen number, heteroatom decoration on the central metal atom were discussed. Based on the rate determining step (RDS), we propose the ideal characters that high-performance SACs should possess.

Self-supported Ni-NiWO4@NC heterojunction as high-efficient electrocatalyst for overall water splitting

Industrial-scale hydrogen energy deployment requires the design of highly efficient catalysts with low overpotential and excellent stability, particularly at high current densities. We report a novel method for fabricating an N-doped carbon coated self-supporting Ni-NiWO4 heterojunction on a nickel foam (NF) catalyst (Ni-NiWO4@NC/NF) using a facile combination of hydrothermal and chemical vapor deposition techniques. The Ni-NiWO4@NC's plentiful catalytic active sites and their seamless contact with NF, along with the synergistic coupling of N-doped carbon, contribute to a decrease in charge transfer resistance and an improvement in catalyst stability. Impressively, when evaluated as an electrocatalyst in alkaline media, the overpotentials of Ni-NiWO4@NC/NF at a current density of 100 mA·cm−2 are only 125.6 mV for hydrogen evolution reaction (HER), and 308.8 mV for oxygen evolution reaction (OER), respectively. The catalyst also demonstrates exceptional stability for HER, OER, and water splitting at high current densities. In addition, the two-electrode electrolyzer using Ni-NiWO4@NC/NF as both cathode and anode need a cell voltage of 1.72 V to deliver 100 mA·cm−2. These findings offer valuable insights into the design and advancement of self-supported non-noble transition metal electrocatalysts for large-scale hydrogen production in industrial applications.

Low-cost micro-supercapacitors using porous Ni/MnO2 entangled pillars and Na-based ionic liquids

The enhanced areal energy of three-dimensional (3D) micro-supercapacitors has made these miniaturized energy-storage components increasingly important at the dawn of the Internet of Things. Although ultrahigh-capacitances have been obtained with Ru-based pseudocapacitive materials, their substitution with abundant non-noble transition metals is a key requirement to reduce the price of electrochemical micro-storage systems and enable long-term sustainability. Here we report a cost-effective and industrially feasible approach to realize 3D micro-supercapacitors based on highly porous scaffolds of Ni/MnO2. These low-price electrodes exhibit a huge areal capacitance exceeding 4 F cm−2 and excellent cycling stability. In addition, extended cell voltages up to 2.6 V with areal energy of 1159 mJ cm−2 (i.e. 0.3 mWh cm−2) and high power of 11.1 mW cm−2 were achieved using innovative Na-based ionogel electrolytes. We also show a novel micro-supercapacitor design based on entangled porous Ni/MnO2 pillars, combining both energy and power ability on a small footprint area.

High-efficiency sustainable energy driven alkaline/seawater electrolysis using a novel hetero-structured non-noble bimetal telluride nanorods

The development of non-noble, economical, and efficient electrocatalysts for water electrolysis will be inevitable for the upcoming green hydrogen economy. In consideration of this, we developed non-noble dual transition metal telluride nanorods through a facile single step hydrothermal method. The optimized CoMnTe2-1 nanorods requires a minimum overpotential of about 120 mV to reach a current density of 10 mA cm−2 in 1.0 M KOH towards the hydrogen evolution reaction (HER). Additionally, we evaluated the theoretical coordination calculations and investigated mechanistic HER pathways using density functional theory calculations. Furthermore, the fabricated water splitting device with CoMnTe2-1 anode displays a cell voltage of 1.60 V and 1.64 V to attain a current density of 10 mA cm−2 in alkaline and alkaline/seawater electrolytes, respectively. As a prototype, we also utilized renewable heat and mechanical energy to drive a self-powered water electrolysis device. This provides a promising path forward in designing an active and efficient bimetal telluride based electrocatalysts for green hydrogen production via alkaline/seawater electrolysis.

A Study on the Electrochemical Performance of MOF Based HER Catalysts for Anion Exchange Membrane Water Electrolysis

Recently, research on anion exchange membrane water electrolysis (AEMWE) has been conducted, which has the advantage of using a non-noble transition metal catalyst to reduce cost and improve the activity and durability of the catalyst. In alkaline solutions, heterojunction catalysts are favored because the rational design of catalysts requires the ability to simultaneously dissociate water and bind hydrogen species.In this study, N-doped carbon hollow polyhedron (NCHP) supports were synthesized using two types of metal-organic frameworks (MOFs) to enhance catalyst durability by effective active site-support interactions. Moreover, well dispersed MoC on MOFs with regularly connected metal nodes and organic ligands increased the number of active sites and improved the reaction kinetics owing to the synergistic effects between MoC and Co@NC, which enhanced the hydrogen evolution reaction (HER).The formation mechanism of NCHP was confirmed by transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. During the half-cell test, the incorporation of MoC (MoC-Co@NC/NCHP) reduced the HER overpotential by approximately 1.8 times at 10mA/cm2 compared with that of Co@NC/NCHP. Furthermore, durability cycling was conducted from 0.1 to -0.6 V versus a reversible hydrogen electrode (RHE). The durability tests revealed that after 3000 cycles, the reduction in the HER current of MoC-Co@NC/NCHP was 1.4 and 2.7 times lower than those of Co@NC/NCHP and commercial Pt/C, respectively. This study provides two strategies to obtain highly stable NC matrix supports and highly active heterojunction catalysts.

Photophysical, electrochemical and electrochromic behavior of transition metal complexes with 1,10-phenanthroline ligands

A series of non-noble transition metal complexes were synthesized by coordinating Fe2+, Co2+, and Ni2+ with ligands having a parent structure of 4,7-diphenyl-1,10-phenanthroline (L1 and L2) and dipyrido[3,2-a:2′,3′-c]phenazine (L3–L5), and their photophysical, electrochemical, and electrochromic properties were studied. Both transition metal ions and ligands produce more or less influence on these properties. Electrochromic properties such as color, optical contrast, response time, coloration efficiency and switching stabilities can be tuned by selecting proper metal ions, parent structure of ligands, and substituent groups. Theory calculation results indicate that electrons flow from the metallic center to the ligands. The UV–vis spectra of all five Fe(II) complexes showed a broad and strong MLCT band at ca. 530 nm. The UV–vis spectra of Fe(II), Co(II) and Ni(II) complexes with L2 ligand showed a strong LC (π–π*) band at ca. 325 nm. Electrochromic process caused a change in the intensity of LC and MLCT absorption. The ligands produced little effect on the bleached and colored states of Fe(II) complexes, all of them showed a bleached state of red and a colored state of purple-red probably due to the reversible Fe(II)/Fe(III) transition. Both Co(II) and Ni(II) complexes showed a bleached state of pale yellow, however, the ligands produced significant effect on their colored states probably due to the partially electron density displacement between the metal ions and the ligands. When the parent structure of ligand is 4,7-diphenyl-1,10-phenanthroline, electron-donating substituent such as –OCH3 is beneficial to electrochromic properties, and Fe(II) complexes have higher optical contrast and coloration efficiency compared to Co(II) and Ni(II) complexes. When the parent structure of ligand is dipyrido[3,2-a:2′,3′-c]phenazine, –CN substituent markedly enhances the optical contrast and coloration efficiency of Fe(II), Co(II) and Ni(II) complexes.

Well-dispersed NiFe nanoalloy embedded on N-doped carbon nanofibers as free-standing air cathode for all-solid-state flexible zinc-air battery

Flexible zinc-air battery (ZAB) is a viable candidate for energy storage in upcoming flexible-wearable technologies. Non-noble transition metal alloys are used to synthesize oxygen evolution reaction (OER) catalysts to facilitate this development. However, inhibiting self-aggregation and promoting high OER activity in alloy nanoparticles is still challenging. Anchoring metal alloys to carbon support materials may produce a strong metal alloy‑carbon support couple, thereby preventing nanoparticle aggregation. Here, the combination of polyacrylonitrile (PAN), polymethyl methacrylate (PMMA), pyrrole, and Ni/Fe salts resulted in homogeneously NiFe nanoparticles embedded in the free-standing nitrogen-doped‑carbon nanofiber (NiFe-N@CNF), produced via electrospinning and followed by carbonization. The NiFe-N@CNF shows a high OER activity with an overpotential of 351 mV. Importantly, good structural stability of NiFe-N@CNF results in superior OER stability with no voltage change after 14 h of chronopotentiometry stability test. The constructed rechargeable aqueous ZAB with NiFe-N@CNF as the air–cathode displays high peak power density (179 mW cm−2) and high stability up to 500 h. With its flexible properties, free-standing NiFe-N@CNF is also used as all-solid-state ZAB cathode, exhibiting stable performance under both flat and bending conditions, proving the promising application of NiFe-N@CNF for flexible-wearable technologies.

Dual-Doping Strategy for Enhancing Hydrogen Evolution on Molybdenum Carbide Catalysts

Hydrogen evolution reaction (HER) is a topic of great interest due to its efficient hydrogen production properties, which can address the increasing demand for clean and sustainable energy sources. On the other hand, molybdenum carbide (MoC) has been widely studied due to its noble metal-like surface electronic properties. In the HER process, it is crucial to regulate the Mo−H bonding energy effectively and increase the electron transfer rate on the MoC catalyst surface in a rational manner. In this study, we introduce highly electronegative nitrogen and non-noble transition metal atoms (Cu or Co) into the molybdenum carbide crystal lattice (N−M−MoC, M: Cu, or Co), which leads to a dual—doping effect. This effect results in the rearrangement of the electronic configuration on the catalyst surface and the enrichment of electrons around Mo atom, leading to an optimization in the Mo−H bonding energy. Moreover, the unique two-dimensional nano-sheet structure of the N−M−MoC materials further promotes the electron transfer and exposure of active sites. Benefiting from the above, the HER performance of the N−M−MoC is significantly improved. Among them, N−Cu−MoC exhibits the lowest overpotential (η10 = 158 mV) and highest stability (about 30 h) in alkaline solutions.

High entropy promoted active site in layered double hydroxide for ultra-stable oxygen evolution reaction electrocatalyst

In this study, high entropy layered double hydroxide (LDH) grown on nickel foam using a simple hydrothermal method is reported. The high entropy LDH consisting of five different non-noble transition metals of Fe, Ni, Co, Mn, and Cr (denoted as FeNiCoMnCr) exhibits an excellent OER activity in alkaline condition with a low overpotential of 218 mV at a current density of 50 mA cm−2. It is superior to the binary, ternary, and quaternary-metal LDHs. We demonstrate that the high entropy FeNiCoMnCr LDH possesses ultra-stable electrochemical stability at a high current density of 400 mA cm−2 for 600 h, which is the best stability of all the reported high entropy material electrocatalysts so far. The interaction among the multi-metal components along with the resulting electronic structure modulation facilitates the formation of highly-active γ-NiOOH species, significantly boosting catalytic activity; while the high entropy induced phase stability contributes to the superior durability.

Coral-shaped Mn-CuS with hierarchical pores and crystalline defects for high-efficiency H2O2 production via electrocatalytic two-electron reduction

We report the development of non-noble transition metal sulfide catalysts Mn-CuS-x for high-efficiency and selective H2O2 production. In this study, we synthesized Mn-CuS-x with coral-shaped hierarchical porous structure through one-pot hydrothermal reaction. The Mn-CuS-x possesses large specific surface area with plenty of crystalline defects via heteroatom doping of Mn. The Mn-CuS-x kinetically favored 2e− pathway over 4e− pathway, resulting in high selectivity (>92%) to H2O2 production and high H2O2 concentration (∼24.5 mM at 0.6 V vs. RHE) within 3 h for the optimized Mn-CuS-2 catalysts (synthesized with a molar ratio of 1:3:8 (MnCl2·4 H2O: CuCl2·2 H2O: C2H5NS)). The Mn-CuS-2 showed excellent stability, indicating that the Mn-CuS electrocatalysts can simultaneously achieve both high stability and enhanced H2O2 production. Our first-principles calculations further confirmed that the heteroatom Mn doping to CuS thermodynamically makes the 2e–-ORR pathway more favorable. This study provides a green, low-cost, and efficient route to produce H2O2, which is very promising for generating chemicals and liquid fuels.