Nitrogen-doped Carbon Nanosheets Research Articles

The Fabrication of ZIF-L Derived Zns/Mos2@NC Anode Materials for Remarkable Lithium-Ion Storage.

The enhancement of electrochemical performance in lithium-ion batteries can be achieved through the incorporation of MoS2 with carbon materials and various metal sulfides. In this study, a ZnS/MoS2 heterostructure was developed, featuring a two-dimensional nitrogen-doped carbon nanosheet (NC) backbone. The synthesis of ZnMoZIF-L precursors was accomplished by introducing a Mo source in a 1 : 1 molar ratio during the ZIF-L synthesis process. Following high-temperature carbonization and vulcanization treatment, ZnS/MoS2@NC composite materials were successfully synthesized. Compared to the unvulcanized ZnO/MoO3@NC and MoS2 samples, the ZnS/MoS2@NC composite exhibits remarkable lithium storage performance. At a current density of 500 mA g-1, the initial reversible capacity capacity is still as high as 1674 mAh g-1. Furthermore, this composite material demonstrates optimal rate capabilities and a significant contribution to pseudocapacitance. The nitrogen-doped carbon framework effectively mitigates volume changes, while the heterostructural design provides more active sites for lithium-ions, thereby enhancing lithium storage performance.

Decrypting Synergy of Alloy & Metal Nanoparticles Within Nitrogen-Doped Carbon Nanosheets for Zn-Air Batteries with Ultralong Cycling Stability.

The exploration of efficient, robust, and low-cost bifunctional electrocatalysts to drive the commercial application of Zn-air batteries (ZABs) is of great significance but still remains a challenge. Herein, a 1D coordination polymer (1D-CP) derived FeNi alloy & Co nanoparticles (NPs) co-implanted N-doped carbon nanosheets (FNC/NCS) is judiciously crafted and employed as a high-performance electrocatalyst for ultralong lifetime ZABs. The key to this strategy is the leveraging of metal-coordinated melamine to direct the pyrolysis of 1D-CP, enabling the in situ formation of well-dispersed FeNi alloy and Co NPs within the carbon matrix. The resulting FNC/NCS exhibits prominent oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activity with a small overall oxygen potential difference (ΔE = 0.68V). Density functional theory (DFT) simulation demonstrates that the synergistic effect between FeNi alloy and Co NPs can reduce energy barriers, promote electron transfer, and optimize the formation of crucial intermediates, thereby largely boost ORR/OER activity of FNC/NCS. The FNC/NCS-assembled ZABs possess high specific capacity, large power density, and ultralong cycling life in both aqueous (> 3300h) and solid-state (150h) electrolytes. This work provides a viable strategy for 1D-CP-derived bifunctional electrocatalysts and dissects the synergistic effect between different metal species, affording significant guidance for the development of renewable energy materials.

Nitrogen-doped porous carbon nanosheets derived from furfural residue as an oxygen reduction catalyst

The complex pore structure of porous carbon plays a pivotal role in determining the catalytic activity of catalysts involved in the oxygen reduction reaction (ORR), and template methods have emerged as the gold standard in the fabrication of porous carbon. This study describes the preparation of a series of carbon materials that use furfural residue and urea as carbon and nitrogen sources, respectively, in conjunction with KOH as an activating agent through a template method. The prepared catalysts have a large specific surface area and an abundance of micro/mesoporous structures, both of which facilitate ion transport and promote active site exposure. Notably, the sample with a carbon-to-nitrogen mass ratio of 1:4 (FR/C-4) exhibits an exceptionally high specific surface area (2190 m2 g−1) along with an impressive array of pore structures. Compared with commercial Pt/C, FR/C-4 demonstrates superior ORR catalytic activity with a half-wave potential (E1/2) of 0.88 V. Furthermore, FR/C-4 demonstrates remarkable stability and methanol tolerance in alkaline electrolytes, indicating its potential for a wide range of applications, such as fuel cells and metalair batteries.

Nitrogen-doped carbon nanosheet confined PtNi alloy for efficient acidic electrocatalytic hydrogen evolution reaction

Low intrinsic electrocatalytic activity and inferior conductivity limit the application of Ni/NC in acidic electrocatalytic hydrogen evolution reaction (HER). Herein, we prepared nitrogen-doped carbon nanosheet confined PtNi alloy electrocatalysts (PtNi/NC-10) using PtCl62− electrostatic adsorption coupling melamine pyrolysis nitriding strategy. PtNi alloying was confirmed by the crystallinity decrease and lattice expansion of Ni/NC. The alloying and confinement effect of Metal-Organic Frameworks (MOFs) suppresses the oxidation and agglomeration of metal nanoparticles during pyrolysis, thus significantly reducing particle size, increasing specific surface area, and promoting the exposure of active sites. The strong electronic interaction between Pt and Ni optimizeds the surface charge distribution, enhancing the adsorption of H species on electron-rich Pt sites, thereby improving reaction kinetics. In addition, PtNi alloying improves the conductivity of the material, accelerating charge transfer and proton transport. Consequently, the prepared PtNi/NC-10 exhibits superior HER performance than Ni/NC in 0.5 M H2SO4 solution, even comparable to commercial 20 wt% Pt/C, with the overpotentials of 35 mV at 0.01 A cm−2. Furthermore, the electrocatalysts assembled PtNi/NC-10-CP‖RuO2-TFF proton exchange membrane (PEM) electrolyzer only requires 2.32 V cell voltage to achieve 1 A cm−2, presenting practical application prospects. Our work provides a novel idea for designing efficient and stable MOFs confined to alloy-based HER electrocatalysts.

High-Entropy Ag-Ru-based Electrocatalysts with Dual-Active-Center for Highly Stable Ultra-Low-Temperature Zinc-Air Batteries.

The development of advanced bifunctional catalysts for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is significant for rechargeable zinc-air batteries (ZABs). Herein, a unique dual active center alloying strategy is proposed to achieve the efficient bifunctional oxygen catalysis, and the high entropy effect is further exploited to modulate the structure and performance of the catalysts. The MOF-assisted pyrolysis-replacement-alloying method was employed to construct the CoCuFeAgRu high-entropy alloy (HEA), which are uniformly anchored in porous nitrogen-doped carbon nanosheets. Notably, the obtained HEA catalyst exhibits excellent catalytic performance for both ORR and OER, and a peak power density of 136. 53 mW cm-2 and an energy density of 987.9 mAh gZn-1, surpassing the most of the previously reported bifunctional oxygen electrocatalysts. Moreover, the assembled flexible rechargeable ZAB enables excellent performance even at the ultralow temperature of -40°C, with an energy density of 601.6 mAh gZn-1 and remarkable cycling stability up to 1,650 hours. Combined experimental and theoretical calculation results reveal that the excellent bifunctional catalytic activity of the HEA catalyst originated from the synergistic effect of the Ag and Ru dual active centers, and the optimization of the electronic structure by alloying effect.

Co-MOF-derived N-doped carbon nanosheet arrays on biomass carbon fiber membrane for highly sensitive detection of luteolin

Rapid and accurate determination of luteolin (LU) content is important for drug dosage control, treatment and prevention of disease. Traditional chromatographic and spectroscopic methods are gradually replaced by more sensitive and rapid electrochemical detection. 3D carbonized eggshell fiber membrane (3D CEFM) with good electrical conductivity and mechanical stability is prepared at high temperatures. To enhance the sensing performance of LU, nitrogen-doped carbon nanosheet arrays/3D CEFM (Co-NC NSAs/3D CEFM) derived from ZIF-67 nanosheet arrays (ZIF-67 NSAs) are prepared on the surface of 3D CEFM. Due to the synergistic effect, the Co-NC NSAs (thickness ∼ 1 μm, height ∼ 3 μm) provides a shorter electron transport path, while the 3D CEFM (pore size ∼5 μm) offers good electrical conductivity and a large solution contact area. Co-NC NSAs/3D CEFM electrode has a sensitivity of 1.31 μA·μM−1·cm−2 in the 0–60 μM LU and a limit of detection (LOD) of 0.04 μM (S/N = 3). Meanwhile, the electrode demonstrated recoveries of 98.0 % to 103.5 % in real samples, with a relative standard deviation (RSD) of 1.2 to 2.3 %. These results indicate that the electrode has significant potential for practical applications.

Electrooxidation of glycerol to formic acid coupled with Energy-Saving hydrogen production over ruthenium doped Cobalt-Based nanosheet arrays

The utilization of small molecule oxidation reactions as a substitute for the sluggish oxygen evolution reaction (OER) in traditional water electrolysis represents an innovative approach to achieve efficient hydrogen production while concurrently generating value-added chemicals. Herein, we report an energy-saving H2 production system utilizing electrooxidation of glycerol to generate valuable formate. Cobalt–ruthenium oxide nanosheet arrays (CoRuO/CF) and cobalt–ruthenium bimetallic nanoparticles wrapped by nitrogen-doped carbon nanosheet arrays (CoRuCN/CF) were synthesized for glycerol oxidation reaction (GOR) and hydrogen evolution reaction (HER), respectively, using Co-ZIF nanosheets precursor material supported on copper foam (Co-ZIF/CF) as the substrate. Remarkably, the hybrid electrolysis system can achieve a current density of 10 mA cm−2 with only 1.19 V, which is significantly lower than that required by traditional water-splitting systems. This work demonstrates the promising potential of efficiently utilizing biomass energy and achieving a sustainable production process for fine chemical products.

“One stone, two birds”: Salt template enabling porosity engineering and single metal atom coordinating toward high-performance zinc-ion capacitors

Zinc-ion hybrid capacitors (ZIHCs) have received increasing attention as energy storage devices owing to their low cost, high safety, and environmental friendliness. However, their progress has been hampered by low energy and power density, as well as unsatisfactory long-cycle stability, mainly due to the lack of suitable electrode materials. In this context, we have developed manganese single atoms implanted in nitrogen-doped porous carbon nanosheets (MnSAs/NCNs) using a metal salt template method as cathodes for ZIHCs. The metal salt serves a dual purpose in the synthesis process: It facilitates the uniform dispersion of Mn atoms within the carbon matrix and acts as an activating agent to create the porous structure. When applied in ZIHCs, the MnSAs/NCNs electrode demonstrates exceptional performance, including a high capacity of 203 mAh g−1, an energy density of 138 Wh kg−1 at 68 W kg−1, and excellent cycle stability with 91% retention over 10,000 cycles. Theoretical calculations indicate that the introduced Mn atoms modulate the local charge distribution of carbon materials, thereby improving the electrochemical property. This work demonstrates the significant potential of carbon materials with metal atoms in zinc-ion hybrid capacitors, not only in enhancing electrochemical performance but also in providing new insights and methods for developing high-performance energy storage devices.

ZIF-12-derived nitrogen doped porous carbon nanosheets-functionalized with silver nanoparticles for ratiometric molecularly-imprinted electrochemical sensing of D-penicillamine

In this work, an electrochemical platform was developed for detection of D-pencillamine utilizing highly responsive molecularly imprinted polymers (MIPs). This platform operates on a ratiometric principle and is constructed on nitrogen-doped porous carbon nanosheets (N-PCNS) derived from zeolite imidazolate frameworks (ZIF-12) in the presence of saturated solution of zinc sulfate. Subsequently, silver nanoparticles (Ag) were introduced onto the surface of N-PCNS/GCE to enhance conductivity and surface area, and serve as a standard signal. The MIP layer was formed on the Ag@N-PCNS/GCE surface through o-phenylenediamine (o-phen) electro-polymerization in the presence of the D-pencillamine (D-PAN) as a template. Detection of D-PAN relies on measuring ID-PAN/IAg response ratio employing differential pulse voltammetry (DPV). This ratio exhibits a linear correlation with the concentration of D-PAN in the dynamic linear range of 0.161–170 µM, exploiting LOD of 38.0 nM (S/N = 3). The electrochemical sensor offers numerous advantages including low detection limit, accuracy, stability, and sufficient degree of selectivity. Utilizing this platform, D-PAN-containing samples were efficiently analyzed with recovery percentages of 98.0–102.0 % and RSDs of 2.78–3.89 %, demonstrating the accuracy of the method.

Fast Perfluorooctanoic Acid (PFOA) Removal with Honeycomb-like Nitrogen-Doped Carbon Nanosheets: Mechanisms for the Selective Adsorption of PFOA over Competing Contaminants/Water Matrix

Fast Perfluorooctanoic Acid (PFOA) Removal with Honeycomb-like Nitrogen-Doped Carbon Nanosheets: Mechanisms for the Selective Adsorption of PFOA over Competing Contaminants/Water Matrix

Nickel single-atom synergistic iron-nitrogen sites for efficient CO2 electroreduction at a wide potential range

Recently, diatomic site catalysts (DASCs) by introducing a second metal active site have become a research focus in electrochemical CO2 reduction reaction (eCO2RR), as can regulate electronic structure of metal centers and optimize reaction free energies. However, hitherto the studies on the origin of the outstanding performance of DASCs and the accurate identification of active centers are not still clear. Herein, we designed a nickel–iron diatomic site catalyst by loading highly dispersed iron phthalocyanine (FePc) on a nickel single-atom with ultrathin porous nitrogen-doped carbon nanosheet substrate (denoted as FePc/M-LNi-NC). Experimental and calculational results prove that the synergistic catalysis of FePc and carbon nanosheet based Ni single-atom endowed FePc/M-LNi-NC achieving excellent CO2 reduction performance with a maximum CO Faradaic efficiency of 98.8 % at –0.8 V vs. RHE. In particular, the current density of FePc/M-LNi-NC at −1.0 V vs. RHE in an H-type cell (−20.9 mA/cm2) is 5.6 times that of FePc (3.7 mA/cm2). Compared with M-LNi-NC, the potential range of FePc/M-LNi-NC when FECO above 95 % expands from 0.31 to 0.43 V. Density functional theory calculations reveal that the Fe site in FePc/M-LNi-NC has a lower free energy change for *COOH formation (ΔG*COOH) and CO desorption (ΔGCO) than Ni site, thus exhibits higher electrocatalytic activity. Furthermore, the ΔG*COOH on FePc/M-LNi-NC declines from 0.78 to 0.08 eV compared to M-LNi-NC, and the ΔGCO lowers from 1.36 to 0.33 eV compared to FePc, thus FePc/M-LNi-NC achieves high performance for eCO2RR at a wide potential range.

The design of chemisorption and catalysis synergistic defender for efficient room temperature sodium-sulfur batteries

Room temperature sodium-sulfur (RT-Na/S) batteries are a promising candidate for large-scale energy storage systems owing to their low manufacturing cost and high energy density. However, the severe shuttle effects and sluggish reaction kinetics hinder their practical application. Here, a Fe3Se4 nanoparticle anchored three-dimensional nitrogen-doped porous carbon nanosheet was designed as a functional defender to inhibit the shuttle effect and achieve high sulfur utilization. The porous carbon nanosheet builds a fast platform for electron and ion transport and acts as a limiting barrier for polysulfide dissolution and shuttling. Additionally, Fe3Se4 nanoparticles are incorporated to enhance the chemical anchoring and catalytic activity of polysulfides. The ex-situ characterization revealed that the Fe sites can feed electrons to polysulfides, thus facilitating the conversion of long-chain polysulfides to Na2S, resulting in high sulfur availability (323 mAh/g at 2 A/g) and long-term cycle life (72 % capacity retention at 1 A/g for 500 cycles).

Nickel-based dual single atom electrocatalysts for the nitrate reduction reaction

Electrochemical nitrate (NO3−) reduction reaction (NO3−RR) to ammonium (NH4+) or nitrogen (N2) provides a green route for nitrate remediation. However, nitrite generation and hydrogen evolution reactions hinder the feasibility of the process. Herein, dual single atom catalysts were rationally designed by introducing Ag/Bi/Mo atoms to atomically dispersed NiNC moieties supported by nitrogen-doped carbon nanosheet (NCNS) for the NO3−RR. Ni single atoms loaded on NCNS (Ni/NCNS) tend to reduce NO3− to valuable NH4+ with a high selectivity of 77.8 %. In contrast, the main product of NO3−RR catalyzing by NiAg/NCNS, NiBi/NCNS, and NiMo/NCNS was changed to N2, giving rise to N2 selectivity of 48.4, 47.1 and 47.5 %, respectively. Encouragingly, Ni/NCNS, NiBi/NCNS, and NiAg/NCNS showed excellent durability in acidic electrolytes, leading to nitrate conversion rates of 70.3, 91.1, and 93.2 % after a 10-h reaction. Simulated wastewater experiments showed that NiAg/NCNS could remove NO3− up to 97.8 % at −0.62 V after 9-h electrolysis. This work afforded a new strategy to regulate the reaction pathway and improve the conversion efficiency of the NO3−RR via engineering the dual atomic sites of the catalysts.

Fe-Single-Atom Catalysts on Nitrogen-Doped Carbon Nanosheets for Electrochemical Conversion of Nitrogen to Ammonia

Electrochemical nitrogen reduction reaction (NRR) has been established as a promising and sustainable alternative to the Haber–Bosch process, which requires intensive energy to produce ammonia. Unfortunately, NRR is constrained by the high adsorption/activation of the N2 energy barrier and the competing hydrogen evolution reaction, resulting in low faradic efficiency. Herein, a well-dispersed iron single-atom catalyst was successfully immobilized on nitrogen-doped carbon nanosheets (FeSAC-N-C) synthesized from pre-hydrothermally derived Fe-doped carbon quantum dots with an average particle size of 2.36 nm and used for efficient electrochemical N2 fixation at ambient conditions. The as-synthesized FeSAC-N-C catalyst records an onset potential of 0.12 VRHE, exhibiting a considerable faradic efficiency of 23.7% and an NH3 yield rate of 3.47 μg h–1 cm–2 in aqueous 0.1 M KOH electrolyte at a potential of −0.1 VRHE under continuous N2 feeding conditions. The control experiments assert that the produced NH3 molecules only emerge from the dissolved N2-gas, reflecting the remarkable stability of the nitrogen–carbon framework during electrolysis. The DFT calculations showed the FeSAC-N-C catalyst to demonstrate a lower energy barrier during the rate-limiting step of the NRR process, consistent with the observed high activity of the catalyst. This study highlights the exceptional potential of single-atom catalysts for electrochemical NRR and offers a comprehensive understanding of the catalytic mechanisms involved. Ultimately, this work provides a facile synthesis strategy of FeSAC-N-C nano-sheets with high atomic-dispersion, creating a novel design avenue of FeSAC-N-C that can vividly have a potential applicability in the large spectrum of electrocatalytic applications.

Regulating the horizontal confined deposition of lithium metal by Co-Nx modified honeycomb-like carbon nanosheets

The uncontrollable Li dendrite growth as well as the severe volume expansion of Li metal anodes during cycling significantly impedes the practical applications of high-energy-density Li metal batteries. In this work, an innovative modulation strategy has been developed by constructing honeycomb-like nitrogen-doped carbon nanosheets with uniformly anchored cobalt nanoparticles (denoted as Co@HNC) for regulating the Li deposition behavior and meanwhile alleviating volume change during cycling. On one hand, the lithiophilic Co-Nx sites can largely reduce the energy barrier of Li nucleation and subsequently guide horizontal confined Li deposition in the honeycomb-like holes of Co@HNC, which is verified by the density functional theory calculations and in-situ optical microscopy observations. On the other hand, the honeycomb-like carbon framework with good structural integrity can endure the huge volume change during repeated Li plating/stripping processes. Consequently, the optimized Co@HNC electrode delivered a promoted cycling life for over 600 times with high Coulombic efficiency of 98.5 % at 1 mA cm−2. When matched with the high-mass-loading LiFePO4 (20 mg cm−2) or high-voltage LiNi0.8Mn0.1Co0.1O2 cathode, the Li@Co@HNC anode exhibited outstanding cycling stability and rate capability under low negative/positive capacity ratio, demonstrating its great potential in practical applications of high-energy-density lithium metal batteries.

Synergy of atomically dispersed Co–Fe pairs in nano-confined catalytic membranes enabling efficient water purification

Membrane-confined catalysis technologies have demonstrated the promise for continuous and efficient catalytic generation of reactive oxygen species (ROSs) to degrade organic pollutants. However, constructing improved membranes with feasible sub-/nanometer-confined spaces, adequate catalytic activity, and superior stability remains a major challenge for practical applications. Herein, we report the demonstration of a nano-confined catalytic membrane (CoFe-DSAC@GO) composed of bimetallic Co–Fe single-atoms anchored on nitrogen-doped carbon nanosheets and graphene oxide. The CoFe-DSAC@GO membrane exhibits 100 % removal efficiency with high water permeance (137 L m−2 h−1 bar−1), rapid degradation kinetics (0.41 ms–1), and excellent catalytic stability over 72 h. The nano-confined spaces in the CoFe-DSAC@GO membrane facilitate the generation and utilization of ROSs and catalytic activity. Furthermore, theoretical calculations elucidate that the electron transfer among bimetallic Co–Fe single-atom sites promotes peroxymonosulfate (PMS) activation. This work advances the mechanistic understanding and application potential of diatomic synergy in membrane-based nano-confined catalysis for water purification.

MXene/Nitrogen-Doped Carbon Nanosheet Scaffold Electrode toward High-Performance Solid-State Zinc Ion Supercapacitor.

While MXene is widely used as an electrode material for supercapacitor, the intrinsic limitation of stacking caused by the interlayer van der Waals forces has yet to be overcome. In this work, a strategy is proposed to fabricate a composite scaffold electrode (MCN) by intercalating MXene with highly nitrogen-doped carbon nanosheets (CN). The 2D structured CN, thermally converted and pickling from Zn-hexamine (Zn-HMT), serves as a spacer that effectively prevents the stacking of MXene and contributes to a hierarchically scaffolded structure, which is conducive to ion movement; meanwhile, the high nitrogen-doping of CN tunes the electronic structure of MCN to facilitate charge transfer and providing additional pseudocapacitance. As a result, the MCN50 composite electrode achieves a high specific capacitance of 418.4 Fg-1 at 1 Ag-1. The assembled symmetric supercapacitor delivers a corresponding power density of 1658.9 Wkg-1 and an energy density of 30.8 Whkg-1. The all-solid-state zinc ion supercapacitor demonstrates a superior energy density of 68.4 Whkg-1 and a power density of 403.5 Wkg-1 and shows a high capacitance retention of 93% after 8000 charge-discharge cycles. This study sheds a new light on the design and development of novel MXene-based composite electrodes for high performance all-solid-state zinc ion supercapacitor.

(FeO)2FeBO3 nanoparticles attached on interconnected nitrogen-doped carbon nanosheets serving as sulfur hosts for lithium–sulfur batteries

(FeO)2FeBO3 nanoparticles attached on interconnected nitrogen-doped carbon nanosheets serving as sulfur hosts for lithium–sulfur batteries

Guanine-derived core-shell FeCo alloy confined in graphene-like N-doped carbon as efficient bifunctional oxygen electrocatalysts for rechargeable Zn-air batteries

Maximization the synergistic effect of each component in transition metal-carbon complexes is expected to improve the bifunctional oxygen electrocatalysis for rechargeable Zn-air batteries but is still challenging. Herein, nucleobase guanine is employed as a supramolecular precursor to generate the core (FeCo alloy)-shell (carbon) structure embedded in ultrathin graphene-like nitrogen-doped carbon nanosheets (FeCo@NCNSs) via a confinement pyrolysis strategy. Thanks to the generated core-shell structure and bimetallic synergistic effect, the as-prepared FeCo@NCNSs exhibits excellent electrochemical performance in both oxygen reduction reaction and oxygen evolution reaction. As a result, when served as the bifunctional air electrode for a practical Zn-air battery, FeCo@NCNSs exhibits a higher open-circuit voltage (1.553 V) and peak power density (197.30 mW cm−2), as well as the greatly improved long-term cyclic stability compared to the noble metal benchmarks. This work provides a promising approach to integrate various active sites for bifunctional oxygen electrocatalysis and inspires the exploration of simple but efficient electrocatalysts for energy storage and conversion.

Superhydrophobic Co/Fe sulfide nanoparticles and single-atoms doped carbon nanosheets composite air cathode for high-performance zinc-air batteries

Development of a high-performance bifunctional catalyst is essential for the actual implementation of zinc-air batteries in practical applications. Herein, a bifunctional cathode of Co3S4/FeS heterogeneous nanoparticles embedded in Co/Fe single-atom-loaded nitrogen-doped carbon nanosheets is designed. Cobalt-iron sulfides and single atomic sites with Co-N4/Fe-N4 configurations are confirmed to coexist on the carbon matrix by EXAFS spectroscopy. 3D self-supported super-hydrophobic multiphase composite cathode provides abundant active sites and facilitates gas–liquid-solid three-phase interface reactions, resulting in excellent electrocatalytic activity and batteries performance, i.e., an OER overpotential (η10) of 260 mV, a half-wave potential (E1/2) of 0.872 V for ORR, a ΔE of 0.618 V, and a discharge power density of 170 mW cm−2, a specific capacity of 816.3 mAh g−1. DFT analysis shows multiphase coupling of sulfide heterojunction through single-atomic metal doped carbon nanosheets reduces offset on center of electronic density of states before and after oxygen adsorption, and spin density of adsorbed oxygen with same spin orientation, leading to weakened charge/spin interactions between adsorbed oxygen and substrate, and a lowered oxygen adsorption energy to accelerate OER/ORR.