Efficient MnO and Co nanoparticles coated with N-doped carbon as a bifunctional electrocatalyst for rechargeable Zn-air batteries

Developing the low-cost, durable, and efficient bifunctional electrocatalyst for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) plays an important role in the commercial implementation of the Zn-air batteries. Herein, we design and synthesize the MnO and Co nanoparticles coated with N-doped carbon (MC@NC) as an excellent bifunctional oxygen electrocatalyst. It is found that the optimal MC@NC-0.3 exhibits outstanding ORR performance with a positive half-wave potential of 0.82 V and excellent OER activity with a small overpotential of 360 mV at 10 mA cm⁻². When applied in the liquid Zn-air battery, MC@NC-0.3 displays a high maximum power density of 153 mW cm⁻², a large specific capacity of 776 mAh g⁻¹ and the excellent cycling stability with a negligible increase after 300 h. Furthermore, the fiber-shaped all-solid-state Zn-air battery also displays remarkable stability at high current density. This study offers a facile strategy to construct a high-efficient, low-cost, and durable transitional metal-based bifunctional electrode for renewable energy applications.     

Facile synthesis of carbon nanosheet arrays decorated with chromium-doped Co nanoparticles as advanced bifunctional catalysts for Zn-air batteries

The development of low-cost electrochemical catalytic nanomaterials for efficient oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) through structural and composition control is a great challenge. Herein, a 3D hybrid structure is designed by an in-situ approach for growing 2D leaf-like nanosheet arrays on 1D electrospun nanofibers. The resultant catalysts composed of Cr-doped Co nanoparticle decorated N-doped carbon nanosheet and carbon nanofiber are synthesized by subsequent Cr³⁺ impregnation and heat treatment. The excellent properties of the as-prepared cathode benefit from the novel establishment of the 3D structure and the regulating mechanism of the electron density of Co after Cr doping, which simultaneously increases the mass and charge transfer process during the catalytic reaction. Consequently, Cr_0.10-Co@NC exhibits excellent catalytic performance for the ORR (with a half-wave potential of 0.84 V) and OER (with an overpotential of 370 mV). When used in a homemade ZAB for evaluating their practical reversible performance, the device exhibits a higher open-circuit voltage (1.45 V) and a smaller potential gap (0.73 V) with excellent cycle durability of 110 h. This work offers a well-designed structure and development for synthesizing efficient and durable electrocatalysts in electrochemical energy conversion technologies.     

A robust bifunctional electrocatalyst for rechargeable zinc-air batteries: NiFe nanoparticles encapsulated in nitrogen-doped carbon nanotubes

Developing high-efficiency, low-cost, and stable bifunctional oxygen electrocatalysts is essential for the commercialization of rechargeable metal-air batteries. Herein, three-dimensional self-assembled microspheres via in situ encapsulation of NiFe alloy nanoparticles (NPs) into N-doping carbon nanotubes (NiFe@NCNTs) have been achieved through pyrolyzing a mixture of nickel-iron alkoxide and melamine. The as-prepared electrocatalyst exhibits outstanding oxygen reduction reaction (ORR) performance with a half-wave potential of 0.79 V and oxygen evolution reaction (OER) activity with a low overpotential of 330 mV at 10 mA cm^?2. The eminent activity of NiFe@NCNTs is ascribed to high dispersion of active sites (zero-dimensional core-shell structure of NiFe@NC) and one-dimensional conductive network (NCNTs). Accordingly, the zinc-air battery assembled with NiFe@NCNTs as the air cathode exhibits a long cycling life of 200 h with a high energy efficiency of 65.6%. This work may shed new light on the design of advanced bifunctional electrocatalysts toward metal-air batteries.     

Transitional metal alloyed nanoparticles entrapped into the highly porous N-doped 3D honeycombed carbon: A high-efficiency bifunctional oxygen electrocatalyst for boosting rechargeable Zn-air batteries

Rational development of low-cost, durable and high-performance bifunctional oxygen catalysts is highly crucial for metal-air batteries. Herein, transition metal alloyed FeCo nanoparticles (NPs) embedded into N-doped honeycombed carbon (FeCo@N-HC) was efficiently prepared by a one-step carbonization method in the existence of NH₄Cl and citric acid. Benefiting from the honeycomb-like architectures and the synergistic effects of the FeCo alloy with the doped-carbon matrix, the as-synthesized FeCo@N-HC exhibited outstanding oxygen reduction reaction (ORR) with the more positive onset potential (E_onset = 0.98 V vs. RHE) and half-wave potential (E_1/2 = 0.85 V vs. RHE), coupled with outstanding oxygen evolution reaction (OER) with the lower overpotential (318 mV) at 10 mA cm^?2. Besides, the home-made Zn-air battery has the larger power density of 144 mW cm^?2 than Pt/C + RuO₂ (80 mW cm^?2). This research offers some valuable guidelines for constructing robust oxygen catalysts in clean energy storage and conversion technologies.     

M (Co,Ni), N and S tridoped carbon nanoplates as multifunctional catalysts for rechargeable Zn-air batteries and water electrolyzers

Exploration of multifunctional non-precious metal catalysts towards oxygen reduction reaction (ORR), oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is very important for many clean energy technologies. Here, two trifunctional catalysts based on M (Co, Ni), N and S tridoped carbon nanoplates (Co/N/S-CNPs and Ni/N/S-CNPs) are reported. Due to the relatively higher catalytic site content, graphitization degree and smaller charge-transfer resistance, the Co/N/S-CNPs catalyst shows higher activity and stability for ORR (onset potential of 0.99 V and half-wave potential of 0.87 V vs. RHE (reversible hydrogen electrode)), OER (overpotential at 10 mA cm^?2 of 0.37 V) and HER than the Ni/N/S-CNPs catalyst. Furthermore, when constructed with the Co/N/S-CNPs and commercial 20 wt% Pt/C + Ir/C cathodes, respectively, Zn-air battery (ZnAB) based on the Co/N/S-CNPs cathode displays better performance, including a higher power density of 96.0 mW cm^?2 and cycling stability at 5 mA cm^?2. In addition, an alkaline electrolyzer assembled with the Co/N/S-CNPs catalyst as a bifunctional catalyst can reach 10 mA cm^?2 at 1.65 V for overall water splitting and maintain excellent stability even after cycling for 12 h. The present work proves the potential of the Co/N/S-CNPs catalyst for many clean energy devices.     

MOF-derived multi-metal embedded N-doped carbon sheets rich in CNTs as efficient bifunctional oxygen electrocatalysts for rechargeable ZABs

The rational design and preparation of bifunctional electrocatalysts with pleasant oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) performance is crucial for extensive commercial applications of rechargeable Zn–air batteries (ZABs). Herein, we report a simple method to obtain multi-metal (Fe, Ni, Zn) embedded in N-doped carbon sheets entangled with carbon nanotubes (CNTs) as superior oxygen electrocatalysts (FeNi-NCS-2). The resultant FeNi-NCS-2 exhibits an impressive electrochemical performance, providing a reversible oxygen overpotential as low as 0.758 V. The ZAB with FeNi-NCS-2 as the air cathode shows a promising capacity of 639.71 mAh g^?1 at 20 mA cm^?2, a power density of 109.8 mW cm^?2 and cycling stability of over 130 cycles at 10 mA cm^?2 with an energy efficiency of about 55%, superior to the ZAB based on Pt/C–IrO₂. The satisfactory electrocatalytic performance is mainly due to the Fe, Ni-based nanoparticles protected by graphitic carbon layers, hierarchical porous lamellar structures that promote the accessibility between the active centers and the electrolyte as well as self-growing tangled carbon nanotubes that provide fast transmission channels. This study presents a facile way for the synthesis of highly efficient ORR/OER bifunctional electrocatalysts for high-performance rechargeable ZABs.     

In situ induced growth strategy of Co2P nanocrystals encapsulated into stable 3D carbon network as a bifunctional electrocatalyst for Zn-air battery

Rational design of inexpensive and robust carbon-based bifunctional catalysts is of considerable interest for practical application of rechargeable Zn-air battery (ZAB) technology. Herein, a facile in-situ induced growth strategy is developed to construct Co₂P nanocrystals encapsulated into a stable 3D carbon nanotube-modified graphene network (Co₂P@NPCNG). Specifically, cobalt tetranitrophthalocyanine (CoPc(NO₂)₄) is employed not only as the coupling agent to form and complex Co₂P nanocrystals with graphene, but also as the inducer to catalyze the graphitization of melamine to grow the uniform Co₂P nanocrystal-encapsulated CNTs on graphene in situ. Encouragingly, the as-synthesized Co₂P@NPCNG exhibits favorable bifunctional oxygen electrocatalytic activity, fast reaction kinetics and excellent stability. Impressively, both liquid ZAB and all-solid-state ZABs used Co₂P@NPCNG as air-cathode catalysts display considerable open-circuit voltage, charge-discharge property and long lifetime. Significantly, density functional theory (DFT) calculations demonstrate that the superior properties of Co₂P@NPCNG originate to the synergetic contributions between the stable configuration of 3D conductive carbon network and high metallic density of Co₂P. This work may provide feasible and facile avenues to strategically construct high-efficient 3D carbon-based bifunctional electrocatalysts for portable and even wearable devices.     

An efficient metal-free bifunctional oxygen electrocatalyst of carbon co-doped with fluorine and nitrogen atoms for rechargeable Zn-air battery

It is highly critical to explore efficient bifunctional oxygen electrocatalysts for regenerative fuel cells and metal-air batteries. Herein, N, F co-doped carbon material (NF@CB) was synthesized as metal-free efficient bifunctional electrocatalysts by directly pyrolyzing a mixture of carbon black, polytetrafluoroethylene and melamine. Benefiting from the synergistic effects between N and F atoms, NF@CB exhibits a positive half-wave potential (E_1/2) of 0.814 V (vs. RHE) for oxygen reduction reaction, and an operating potential (E₁₀) of 1.609 V at 10 mA cm⁻² for oxygen evolution reaction in alkaline electrolyte. The bifunctional oxygen electrocatalytic activity index (ΔE = E₁₀−E_1/2) is 0.795 V, which is notably better than that of the single N-doped carbon (1.238 V), and similar to that of the commercial Pt/C and RuO₂ mixture catalyst (0.793 V). Impressively, the assembled Zn-air battery (ZAB) with NF@CB as an air-electrode catalyst displays a small charge/discharge voltage gap of 0.852 V at 20 mA cm⁻². Moreover, the NF@CB catalyzed ZAB exhibits good rechargeability and long-lasting cycling stability with over 49 h. This investigation introduces a cheap and simple way to develop highly efficient bifunctional N, F co-doped electrocatalysts.     

TiCN MXene hybrid BCN nanotubes with trace level Co as an efficient ORR electrocatalyst for Zn-air batteries

Developing non-noble metal oxygen reduction reaction (ORR) electrocatalysts with high performance, excellent stability, and low-cost is crucial for the industrialization of fuel cells. Herein, trace level Co modified 3D hybrid titanium carbonitride MXene and boron-carbon-nitrogen nanotubes catalyst (TiCN–BCN–Co) is fabricated by spray-lyophilization and high-temperature pyrolysis. This strategy not only avoids the oxidation of Ti₃C₂T_x MXene, but also introduces nitrogen atoms into the titanium carbide lattice to form a more electrocatalytically active TiCN crystal phase. The obtained TiCN–BCN–Co exhibits superior ORR catalytic activity with a positive half-wave potential of 0.83 V vs. RHE and outperforms commercial Pt/C in terms of stability and methanol tolerance. Impressively, the Zn-air battery with TiCN–BCN–Co cathode achieves a superior specific capacity of 791 mAh g^?1 and long-term stability of 200 h.     

Tunable Fe/N co-doped 3D porous graphene with high density Fe-Nx sites as the efficient bifunctional oxygen electrocatalyst for Zn-air batteries

Nitrogen-doped transition metal materials display promising potential as bifunctional electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Herein, Fe/N co-doped three-dimensional (3D) porous graphene (FeN-3D-PG) is prepared via a template method using sodium alginate as the carbon source and low polymerization degree melamine resin as the nitrogen source. The low polymerization degree melamine resin can form complexes with Fe³⁺ in the aqueous solution and further forms high density Fe-N_x active sites during pyrolysis. Meanwhile, the formed 3D porous structure efficiently promotes the uniform distribution of Fe-N_x active sites. The FeN-3D-PG catalyst exhibits pH-independent ORR activity. For OER, the catalyst possesses a low over potential (370 mV at 10 mA cm⁻²) in alkaline electrolyte. The Zn-air batteries (ZABs) using FeN-3D-PG as cathode exhibits a power density up to 212 mW cm⁻², a high specific capacity of 651 mAh g⁻¹, and the charge-discharge stability of 80 h. This work provides new sight to transition metal materials based ZABs with excellent performance.     

Co,N co-doped carbon nanosheets coupled with NiCo2O4 as an efficient bifunctional oxygen catalyst for Zn-air batteries

Developing of inexpensive and efficient bifunctional oxygen catalysts is important for the zinc-air batteries (ZABs). Here, a composite of Co, N co-doped carbon nanosheets coupled with NiCo₂O₄ (NiCo₂O₄/CoNC-NS) is developed as oxygen catalyst, which has good bifunctional oxygen catalytic activity and durability. Specifically, the half-wave potential of oxygen reduction reactions (ORR) is 0.849 V, and the overpotential of oxygen evolution reactions (OER) is 1.582 V at a current density of 10 mA cm⁻². And the assembled liquid ZABs based on NiCo₂O₄/CoNC-NS exhibit high open circuit potential (OCP, 1.482 V), high peak power density (148.3 mW cm⁻²) and large specific capacity (699.9 mAh g⁻¹) with long-term stability. Moreover, the further assembled solid ZABs can also provide high OCP (1.401 V), good power density (58.1 mW cm⁻²) and superior stability. This work would provide a good reference for the development of other advanced oxygen catalyst in future.     

Nitrogen,sulfur, and oxygen tri-doped carbon nanosheets as efficient multifunctional electrocatalysts for Zn-air batteries and water splitting

Nitrogen, sulfur, and oxygen tri-doped carbon nanosheets (N, S, O-CNs) were prepared by a modified in-situ g-C₃N₄ template method with a plant-waste, rice straw, as the carbon precursor. The N, S, O-CNs could worked as efficient electrocatalysts for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER). Significantly, the introduced S element can particularly activate the electron transfer and accelerate reaction kinetics for HER, while the N/O dopants can efficiently promote the ORR and OER. As a result, the N, S, O-CNs exhibited excellent performance with favorable kinetics and decent durability as a multifunctional ORR, OER and HER catalyst. Moreover, the rechargeable liquid/solid Zn−air battery and water splitting device showed superior performance by assembling this N, S, O-CNs catalyst. This work paves a universal avenue towards further development of plant-waste derived carbon materials with heteroatom dopants as the highly efficient electrocatalysts in energy devices.     

Y and Fe co-doped LaNiO3 perovskite as a novel bifunctional electrocatalyst for rechargeable zinc-air batteries

Perovskite oxides are widely regarded as the promising air electrode catalytic materials for zinc-air batteries (ZABs). In the present work, A-site Y and B-site Fe co-doped La_0.85Y_0.15Ni_0.7Fe_0.3O₃ perovskite catalyst was prepared by self-propagating high-temperature synthesis, and this material was evaluated as a bifunctional electrocatalyst for ZABs. The effect of co-doping on crystal structure and reaction activities, which can promote oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), was investigated. Results show that Y and Fe co-doping substantially improved the ORR and OER of LaNiO₃. In comparison with LaNiO₃, the ORR performance of La_0.85Y_0.15Ni_0.7Fe_0.3O₃ exhibited a higher limiting current density (3.8 mA cm^?2 at 0.4 V vs. RHE) and more positive onset potential (0.75 V vs. RHE) at 1600 rpm. It also had an excellent OER performance of 1.74 V vs. RHE at 10 mA cm^?2. When La_0.85Y_0.15Ni_0.7Fe_0.3O₃ was used as an air electrode catalyst for ZABs, it exhibited a high power density of 93.6 mW cm^?2, which increased by 84.8% compared with that of LaNiO₃. Moreover, the full cell with La_0.85Y_0.15Ni_0.7Fe_0.3O₃ air electrode catalyst was operated for more than 80 h, maintaining good stability. Therefore, La_0.85Y_0.15Ni_0.7Fe_0.3O₃ can be used as a promising bifunctional air electrode catalyst for ZABs. The characterization analysis reveals that A-site Y and B-site Fe co-doped catalyst transforms crystal structure from trigonal system to cubic system, retain the valence state of Ni³⁺ and increases the contents of O₂^2?/O^?, and these properties are more conducive for LaNiO₃ catalysis.     

Design and synthesis of dispersed Ni2P/Co nano heterojunction as bifunctional electrocatalysis for boosting overall water splitting

The design of multi-components nanostructure with interface heterojunction is the cutting-edge research in recent years because the catalytic activity, stability, and durability of catalysts are highly affected by the strong electronic effects, geometric effects, and synergistic effects occurring at the interface. Based on this, an efficient bifunctional electrocatalyst embedding highly dispersed Ni₂P/Co nano heterojunction at the porous hollow-out carbon shell is developed for overall water splitting through evenly epitaxial growth of ultrathin Ni₂P nanosheets on Co-based ZIF-67. The distinct electron interaction between the interfacial Ni₂P (300) and Co (100) effectively lowers the overpotential of OER (316 mV vs. RHE) and HER (149 mV vs. RHE) at the current density of 10 mA cm^?2. Density functional theory (DFT) calculation further identifies that the Ni₂P and Co heterojunctions optimize the adsorption energy of intermediate products and lower the energy barrier of the rate-determining step of OER significantly. This work provides a rational design of a well-defined interface toward overall water splitting electrocatalysts and offers a scientific basis for an in-depth understanding of the mechanism of the catalysts with nano heterojunction.     

Embedding Co2P nanoparticles into co-doped carbon hollow polyhedron as a bifunctional electrocatalyst for efficient overall water splitting

The reasonable design and construction of non-precious metal electrocatalysts with low cost and high performance is critical for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, a facile polymerization-pyrolysis method is proposed to encapsulate Co₂P nanoparticles in co-doped hollow carbon shell by using ZIF-67 and P-containing polymers as precursor. The unique construction not only effectively prevents nanoparticles from detaching, showing good stability after long-term testing, but also provides abundant active sites, large surface areas and large pore volumes, enabling the electrolyte and electrode material to full contact. As expected, the Co₂P/NPSC-800 performs superior HER performance with low overpotential of 173 mV at 10 mA cm⁻² and excellent stability of 88% retention for 35 h and OER performance with low overpotential of 320 mV at 10 mA cm⁻², which endows Co₂P/NPSC-800 with good catalytic activity in overall water splitting. Furthermore, density functional theory (DFT) calculations reveal that the metallic property and the decreased reaction barriers of Co₂P can promote the catalytic reactions. This work offers an effective route in synthesizing other transition metal phosphides with high catalytic properties.     

Coupling molybdenum carbide nanoparticles with N-doped carbon nanosheets as a high-efficiency electrocatalyst for hydrogen evolution reaction

Searching for earth-abundant and high-efficiency electrocatalysts for the hydrogen evolution reaction (HER) is of critical importance for future energy conversion devices. To facilitate the HER on a nonprecious metal-based catalyst, integration of catalytically active nanoparticles with highly conductive carbon supports represents a promising strategy since the formed nanohybrid can offer available active sites and improved electron transfer capability. Herein, we demonstrate a feasible and scalable approach to fabricate well-dispersed Mo₂C nanoparticles firmly anchored on 2D ultrathin N-doped carbon nanosheets (denoted as Mo₂C@NC nanosheets) using inexpensive NaCl as recyclable templates. The adoption of NaCl template provides a 2D space for the one-step concurrent growth of Mo₂C nanoparticles and N-doped carbon nanosheets. Benefiting from the synergy between fine Mo₂C nanoparticles with high dispersity and N-doped C nanosheets, the resultant Mo₂C@NC nanosheets exhibit an outstanding HER performance with a low overpotential, a small Tafel slope and excellent stability under acidic medium, making them a promising noble-metal-free HER catalyst.     

A dual ligand coordination strategy for synthesizing drum-like Co,N co-doped porous carbon electrocatalyst towards superior oxygen reduction and zinc-air batteries

We herein propose a dual ligand coordination strategy for deriving puissant non-noble metal electrocatalysts to substitute valuable platinum (Pt)-based materials toward oxygen reduction reaction (ORR), a key reaction in metal-air batteries and fuel cells. In brief, cobalt ions are firstly double-coordinated with proportionate 2-methylimidazole (2-MeIm) and benzimidazole (BIm) to obtain drum-like zeolitic imidazolate frameworks (D-ZIFs), which are then carbonized to output the final Co, N co-doped porous carbon (Co–N–PC_D) catalyst inheriting the drum-like morphology of D-ZIFs. The Co–N–PC_D is featured by mesopores and exhibits superb electrocatalytic behavior for ORR. Impressively, the half-wave potential of Co–N–PC_D catalysts is 0.886 V with finer methanol-tolerance and stability than those of commercial Pt/C. Additionally, a zinc-air battery assembled from the Co–N–PC_D displays an open-circuit voltage of 1.413 V, comparable to that of commercial Pt/C (1.455 V), suggesting the potentials of Co–N–PC_D in practical energy conversion devices.     

MOF-derived NiSe2 nanoparticles grown on carbon fiber as a binder-free and efficient catalyst for hydrogen evolution reaction

It is challenging to grow inexpensive cathode material with superior catalytic properties for hydrogen evolution reaction (HER). Metal-organic frameworks (MOFs) have emerged as powerful platforms to synthesize efficient and ultrastable catalysts for hydrogen production. In this research, NiSe₂ nanoparticles were derived from Ni-based MOF, which grown in situ on carbon fiber (NiSe₂/C/CF) through pyrolysis and selenization processes. NiSe₂/C/CF displays a higher HER performance than that of Ni/C/CF and Ni-MOF-74/CF. Notably, the NiSe₂/C/CF electrode gives a low overpotential of 209 mV, a Tafel slope of 74.1 mV/dec, and outstanding stability with slight decay after operating for 12 h. The high HER catalytic activity of NiSe₂/C/CF is mainly ascribed to the emerging effects of NiSe₂ nanoparticles and three-dimensional conductive substrate CF, facilitating active moieties exposure and electron transfer during the electrocatalytic process. Therefore, this work illustrates a novel approach for the preparation of transition metal chalcogenides as low-cost and stable catalysts for HER.     

Petal-like NiCoP sheets on 3D nitrogen-doped carbon nanofiber network as a robust bifunctional electrocatalyst for water splitting

Searching high-active, stable and abundant bifunctional catalysts to replace noble metals for hydrogen and oxygen evolution reactions (HER and OER) is desired. Herein, petal-like NiCoP sheets were synthesized on carbon paper covered with a 3D nitrogen-doped carbon nanofiber network (NiCoP/CNNCP) by a simple hydrothermal process followed by phosphorization. The HER overpotential in 0.5 M H₂SO₄ and OER overpotential in 1 M KOH of the NiCoP/CNNCP electrode only required 55 mV and 260 mV to drive a current density of 10 mA cm^?2, respectively, which was comparable or even better than most nickel-and cobalt-based phosphide catalysts. The overall water-splitting electrolyzer with an asymmetric electrolyte system assembled using NiCoP/CNNCP as bifunctional electrodes required an extremely low cell voltage of 1.04 V to achieve a current density of 10 mA cm^?2, which was much lower than almost all alkaline electrolysis systems.     

Thermal treatment of Co(II) tetracarboxyphenyl porphyrin supported on carbon as an electrocatalyst for oxygen reduction

Ultraviolet–visible and fourier transform infrared absorption spectra indicate that polytetraphenylporphyrin Co (II) (PTPPCo) can be obtained by heat-treating 5,10,15,20-tetra (4-carboxyphenyl)-porphyrin Co (II) (TCPPCo) at 400 °C in argon atmosphere. Polytetraphenylporphyrin Co/C is obtained by heat treatment (HT) of TCPPCo, which is adsorbed on Vulcan XC-72 with different Co–N₄ loading, from 400 °C to 1000 °C in argon atmosphere. Catalysts are evaluated for electroreduction performances of oxygen on modified electrodes in sulfuric acid solutions. Results from electroreduction of the catalyst (HT 600 °C and 6 wt% Co–N₄ loading) show the original reduction voltage is 0.81 V versus the reversible hydrogen electrode, and the transfer electron number is 3.83. The morphology, distribution, and surface elemental analysis of the catalysts are characterized by x-ray diffraction spectroscopy and transmission electron microscopy with energy dispersive x-ray. PTPPCo can homogeneously anchor on the carbon support and withstand decomposition upon heat treatment at 600 °C. Since TCPPCo results in polymerization on XC-72, pi (π) bond increases significantly with the decrease in π-electron delocalization energy. Improved capacity in electron gain or loss is observed, and the center of electrocatalysis is clearly exposed. Thus, the activity, stability, and selectivity of the catalyst presented in this paper are proven better than those of other common catalysts.