Heteroatom-doped Carbon Research Articles

Red-emitting carbon dots as luminescent agent in wide-range water detection in organic solvents and polarity-selective zebrafish imaging

Heteroatom-doped carbon dots with promising luminescent properties are excellent candidates for sensing and imaging applications. Herein, we reported a facile one-step hydrothermal synthesis of highly-fluorescent red-emitting carbon dots (R-CDs) with quantum yield of 37.2 %. R-CDs exhibit a maximum emission band at 640 nm under the excitation wavelength of 500 nm. Furthermore, R-CDs show excitation-dependent and solvent-engineered fluorescent characteristics that the luminescent properties could be greatly affected by polarity. Due to the sensitivity to polarity, a quick and precise approach for wide-range water detection in organic solvents has been developed. Because of the low autofluorescence background, R-CDs were applied to the zebrafish larvae imaging. Polarity-selective bright red light from R-CDs is seen in the low-polarity organs like yolk sac and eyes, which contain abundant lipids and lipoprotein. Our results demonstrate that R-CDs could be used as bio-imaging agents and fluorescent sensors for quantitative and visual water detection in various organic solvents. • High-fluorescent red-emitting carbon dots are synthesized from hydrothermal treatment of DMAB and boric acid. • Bright red emission at 640 nm (λ ex = 500 nm) and high QY of 37.2 % are achieved. • The variation of the emission intensity of R-CDs is highly dependent on solvent polarity. • Polarity-selective bright red light from R-CDs is seen in the low-polarity organs like yolk sac and eyes.

Interfacial engineering of SnO2/Bi2O2CO3 heterojunction on heteroatoms-doped carbon for high-performance CO2 electroreduction to formate

Interfacial engineering of SnO2/Bi2O2CO3 heterojunction on heteroatoms-doped carbon for high-performance CO2 electroreduction to formate

A Janus heteroatom-doped carbon electrocatalyst for hydrazine oxidation.

The trade-off between the intrinsic activity and electronic conductivity of carbon materials is a major barrier for electrocatalysis. We report a Janus-type carbon material combining electrically conductive nitrogen-doped carbon (NC) and catalytically active boron, nitrogen co-doped carbon (BNC). The integration of NC with BNC can not only ensure high electronic conductivity of the hybrid, but also achieve an enhancement in the intrinsic activity of the BNC side due to the electron redistribution on their coupling interfaces. In the electrocatalytic hydrazine oxidation reaction (HzOR), the Janus carbon electrocatalyst exhibits superior activity than their single counterparts and simple physical mixtures. Density functional theory calculations reveal that the NC/BNC interfaces simultaneously promote efficient electron transport and decrease the free energy of the rate-determining step in the HzOR process.

Polypyrrole-derived carbon nanotubes for potential application in electrochemical detection of dopamine

Dopamine (DA), as a crucial signal molecule in neurological diseases, can be detected by electrochemical technology because of its redox property. A novel electrochemical sensor for dopamine (DA) is developed based on heteroatom-doped carbon nanotubes derived from polypyrrole. X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, specific surface analyzer, and cyclic voltammetry are employed to characterize the microstructure and property of the products. The electrochemical catalytic activities of heteroatom-doped carbon nanotubes modified glassy carbon electrode (GCE) towards DA are further investigated by cyclic voltammetry, amperometry, and differential pulse voltammetry. The results indicate that heteroatom-doped carbon nanotubes prepared by pyrolysis of polypyrrole nanotubes at 800 °C possessed higher specific surface area and better electrochemical activity compared with others obtained at different temperatures. Therefore, the electrochemical sensor fabricated by the heteroatom-doped carbon nanotubes shows excellent detection ability towards DA as well as remarkable anti-interference ability and stability. These features collectively endow the polypyrrole-derived carbon nanotubes with a promising application for the fabrication of electrochemical sensors.

Synthesis and Characterisation of High Performing Heteroatom Doped Carbon Catalyst for Oxygen Reduction Reaction (ORR) in Alkaline Fuel Cells

Alkaline fuel cell (AFC) routing platinum-free electrocatalysts are one of the potential frontiers to enable its use in widespread applications. PGM catalysts have alwaysbeen preferred andwidely utilised due to their enhanced intrinsic activity and superior performance. Its high cost and less abundance brought attention to heteroatom doped carbon-based electrocatalysts that offer comparable performance, tunable selectivity and simple synthesis route. The lack of efficient catalysts hampers the performance, peak power density and longevity of the cell due to sluggish ORR activity.In this article, Heteroatom-doped carbon (F, N/F and N/S/F) is prepared using PVDF-HFP polymer as a precursor. The polymer is mixed with urea or ThioUrea concerning the required dopant and pyrolyzed at 900 ºC for 3 hours at a heating rate of 5 deg per min in an inert atmosphere. The enhanced performance is obtained from the N/F- doped carbon which shows an onset potential (E = 1.04V vs. RHE), a diffusion-limited current density(j) of 6.12 mA/cm2 in 0.1M KOH, which is comparatively better than the F-doped and N/S/F-doped carbon. The number of electrons (n) involved in the ORR activity was calculated to be 3.99, 3.98, 3.85 for N/F-C, N/S/F-C and F-C respectively. This suggests a 4e- pathway indicating efficient operation for the Alkaline electrochemical cell. The systematic studies exhibit an increased ORR activity in the case of the N/F-doped carbon electro-catalyst due to a combined synergistic effect of hetero-atoms and high surface area. Heteroatom doping and the activity in the carbon material were confirmed by all the necessary physical and electrochemical characterisations. Keywords: Hydrogen, Alkaline Fuel cell, AFC, Oxygen reduction reaction, ORR catalyst

(Invited) Surface Electrochemistry and Physicochemical Behaviors of Carbon and Compound Electrodes in Electrochemical Separation Systems

In recent years, electrochemical separation systems have received a great attention due to their excellent capabilities in environmental remediation, water desalination, and resource recovery. The performances of electrochemical separation systems are often interpreted in terms of capacity and selectivity, both of which are highly dependent on electrode materials. For instance, capacitive deionization (CDI) used for desalination of water employs activated carbon electrodes, as it enables capture and release of sodium chloride in large amounts. In addition, lithium-ion selective electrode such as delithiated LiMn2O4 (i.e. λ-MnO2) or LiFePO4 plays an essential role in selectivity of electrochemical lithium recovery systems. However, although the importance electrode materials cannot be overemphasized for such electrochemical separations, it is also true that we are yet to achieve a sufficient level of understanding on their behaviors in the systems, which is necessary to establish rational electrode-design strategies to enhance capacity and selectivity of the electrochemical separation systems. In this talk, our recent findings on surface electrochemistry of carbon electrodes in electrochemical desalination will be introduced, together with an overview on the non-favorable Faradaic reactions thoroughly characterized with the assistance of various X-ray and electrochemical techniques. Additionally, development of heteroatom-doped carbon material and how it resulted in a highly stable CDI performance will be presented. Moreover, I will talk about our efforts on characterization of physicochemical behavior of λ-MnO2 in electrochemical lithium recovery systems, based on which a significantly higher utilization rate of the electrode materials could be achieved.

Nitrogen-doped carbon layer on cellulose derived free-standing carbon paper for high-rate supercapacitors

Free-standing porous carbon have risen to prominent electrode materials for high-rate solid-state supercapacitors, yet they are still plagued by uneconomical petrochemical feedstocks, tedious slurry-casting processes, and suboptimal performance. Herein, a dual‐strategy of combining free-standing nitrogen-doped carbon nanowire array coating and pore engineering is designed to boost the performance of cellulose-derived carbon electrodes. Polyformamide-derived carbon nanowire arrays are in-situ synthesized as N-containing carbon coatings for cellulose-based carbon fibers. More intriguingly, H2O2 activation further enhances the hierarchical porous structure. Benefiting from the synergistic effect of free-standing feature, high electrolyte compatibility, interconnected conductive fiber networks, well-developed hierarchical porous structure and stable heteroatom-doped carbon coatings, the designed electrodes possess high accessibility of electrolyte ions and effective ion/electron transport channels. Thus, the specific capacitance reaches 275.6F g−1 at 0.5 A g−1 for aqueous supercapacitor. The solid-state symmetric supercapacitor demonstrates the specific capacitance of 126.5F g−1 at 0.5 A g−1 with the capacitance retention of 64.5% even when the current densities increased by 40-folds. Their promising energy density (17.5 Wh kg−1) and power density (12.3 kW kg−1) closing to the state-of-the-art biomass-derived free-standing solid-state symmetric supercapacitors. This breakthrough symbolizes a step forward in the advancement of biomass as high‐performance electrodes for supercapacitors.

Ultra-high voltage efficiency rechargeable zinc-air battery based on high-performance structurally regulated metal-rich nickel phosphides and carbon hybrids bifunctional electrocatalysts

Metal phosphides featuring electronic structure similar to Pt-group metal have triggered substantial concerns, and unveiling active species is crucial to rational design of bifunctional catalysts for ORR and OER. Herein, a hybrid of metal-rich nickel phosphides strongly coupled with heteroatom-doped carbon (NixP-NP-C) is constructed by a facile pyrolysis combined with in-situ phosphorization of MOFs. This unique hybrid exhibits superior electrocatalytic activity and stability toward ORR and OER demonstrated by delightful high Eonset and E1/2 up to 0.90 and 0.76 V, respectively, along with a long-term stability. The resulting zinc-air battery shows an impressively small charge-discharge voltage gap and delivers a high power density of 266 mW cm−2. The high catalytic performance of NixP-NP-C can be ascribed to synergistic effect of metal-rich Ni2P actives and heteroatoms doped porous carbon. Consequently, hybrid of carbon and metal phosphides may provide a meaningful reference for developing high performance oxygen catalysts in metal-air battery.

Self-assembly of biomass derivatives into multiple heteroatom-doped 3D-interconnected porous carbon for advanced supercapacitors

The rational design of the pore structure of carbon materials is of great significance for solving the low specific capacitance and poor rate performance of supercapacitors. Herein, we propose a multiple heteroatom-doped three-dimensional (3D) interconnected carbon material obtained from the self-assembly of biomass derivatives including chitosan and sodium lignosulfonate with the assistance of boric acid. The amino group of chitosan protonated by boric acid can form electrostatic adsorption and hydrogen bonding with the sulfonic acid group of sodium lignosulfonate to form a carbon network structure. Boric acid also acts as a template, and in combination with KOH activation, further promotes the formation of the hierarchical porous structure, resulting in the as-prepared carbon possessing a high specific surface area of 2700.65 m2 g−1. As the electrode material in 6 M KOH electrolyte, it manifests a decent specific capacitance of 332 F g−1 at 1 A g−1 in the three-electrode system, while the symmetric electrode achieves a high energy density of 17.7 W h kg−1 at 166.4 W kg−1. Moreover, the contribution rate of the fast and slow kinetic process, as well as the fast diffusion of electrolyte ions are deeply revealed through the ultrafast charge/discharge and the ion diffusion kinetics analysis, respectively. The symmetric electrode in PVA/KOH gel electrolyte maintains 97% capacitance retention and 100% Coulombic efficiency over 10000 cycles, indicating excellent cycling stability.

The extended Stӧber method for synthesizing nitrogen-doped porous carbon nanospheres supported Pt nanoparticles towards methanol oxidation in alkaline media

• N -doped porous carbon nanospheres were prepared via the extended Stӧber method. • The NPCs have a high surface area and abundant nitrogen content. • The Pt nanoparticles supported on NPCs showed superior MOR activity and stability. Heteroatom-doped porous carbon materials have emerged as attractive catalyst supports of Pt nanoparticles in the direct methanol fuel cells (DMFCs). Herein, the simple extended Stӧber method towards nitrogen-doped porous carbon nanospheres (NPCs) is reported by polymerizing of 3-aminophenol-formaldehyde (APF) resin spheres. The synthesized NPCs were applied as a carrier for Pt nanoparticles to fabricate the Pt@NPCs catalyst for methanol oxidation. Compared with the commercial Pt/C catalyst, Pt@NPCs showed the larger electrochemically active area (93.6 m 2 g −1 ), higher peak current density (95.91 mA·cm −2 ) and better stability in alkaline media. This improved performance can be attributed to the porous structure of NPCs and nitrogen atoms doped in the carbon matrix increasing the dispersion of the Pt particles on the NPCs catalyst.

Bidirectionally polarizing surface chemistry of heteroatom-doped carbon matrix towards fast and longevous lithium-sulfur batteries

Herein, a bidirectional polarization strategy is proposed for hosting efficient and durable lithium-sulfur battery (Li-S) electrochemistry. By co-doping electronegative N and electropositive B in graphene matrix (BNrGO), the bidirectional electron redistribution enables a higher polysulfide affinity over its mono-doped counterparts, contributing to strong sulfur immobilization and fast conversion kinetics. As a result, BNrGO as the cathode host matrix realizes excellent cycling stability over 1000 cycles with a minimum capacity fading of 0.027% per cycle, and superb rate capability up to 10 C. Meanwhile, decent areal capacity (6.46 mAh/cm2) and cyclability (300 cycles) are also achievable under high sulfur loading and limited electrolyte. This work provides instructive insights into the interaction between doping engineering and sulfur electrochemistry for pursuing superior Li-S batteries.

Carbon doped with binary heteroatoms (N,X–C, where X = P, B, or S) derived from polypyrrole for enhanced electromagnetic wave absorption at microwave frequencies

Dual heteroatom-doped carbon materials show great promise as electromagnetic wave absorbers. However, synthesizing carbons containing multiple heteroatoms at controlled heteroatom doping levels has provided challenges to date. Herein, we report a simple method for manufacturing dual heteroatom doped carbons (N,X–C, where X = P, B, or S) by direct carbonization of polypyrrole synthesized in the presence of H3PO4, H3BO3, or H2SO4, respectively. The heteroatom content of the N,X–C products could be precisely tuned by varying amounts of acid dopant used in the polypyrrole synthesis. The N,X–C materials showed excellent electromagnetic wave absorption properties, especially N,S1–C (prepared using equimolar amounts of pyrrole and H2SO4) which offered a wide absorption bandwidth up to 6.6 GHz (11.38–18 GHz), and a RLmin of −32.3 dB (14.2 GHz) at 2.5 mm at a filler loading of 9.0 wt%. The outstanding electromagnetic wave absorption performance of N,S1–C was attributed to the presence of N dopant species, defects, C–S, and C–SOx groups, which optimized dipole polarization and conduction loss in the dielectric loss leading to excellent impedance matching.

Supermolecule-mediated defect engineering of porous carbons for zinc-ion hybrid capacitors

Zinc ion hybrid capacitors hold great potential for future energy storage that requires both high energy density and high power capability. However, the charge storage mechanism of porous carbon cathode is ambiguous in Zn2+ ion-containing aqueous solutions, albeit porous carbon usually stores charge by electric double-layer capacitance. Herein, we developed a supermolecule-mediated direct pyrolysis carbonization strategy to convert sustainable sodium lignosulfonate resources into three-dimensional highly heteroatom-doped porous carbons with large mesopores. Through this strategy, we obtained lignin-derived porous carbons with high heteroatom dopings (14.9 at% nitrogen and 4.7 at% oxygen) and relatively high specific surface areas. Furthermore, the nitrogen doping configurations were mainly edge-nitrogen dopants even under high pyrolysis temperatures (> 900 °C). Lignin-derived nitrogen-doped porous carbon showed a high gravimetric specific capacitance of 266 F g−1 with high rate capability, which is endowed by the increased surface pseudocapacitance. First-principles calculations and molecular dynamics simulations indicate that the edge nitrogen and oxygen dopants contribute to the reversible adsorption/desorption of zinc ions and protons. Pores size less than 6.8 Å can cause a significant diffusion energy barrier for the hydrated zinc ions, thus degrading the capacitance and rate capability.

Carbon Materials as Catalytic Tools for Oxidative Dehydrogenations and Couplings in Liquid Phase

AbstractCarbocatalysis is a heterogeneous metal-free catalytic technique of high potential for current and future synthetic processes. Carbocatalysts entail heterogeneous materials based on sp2/sp3 interconnected carbons decorated with oxygen functional groups, defects, and other heteroatom dopants. In this short review, we cover a wide range of different carbocatalyzed oxidative dehydrogenation reactions, with particular emphasis on liquid-phase transformations that are relevant for synthetic organic chemists.1 Introduction2 Structures of Catalytic Carbon Materials3 Oxidative Aromatizations with Activated Carbon4 Oxidative Dehydrogenation CH–CH Couplings5 Oxidative Dehydrogenation Coupling of Benzyl Amines6 Oxidations of Alcohols7 Other Oxidative Transformations by Heteroatom-Doped Carbon Materials8 Asphaltene Oxide9 Conclusions and Outlook

Molecular engineering toward sustainable development of multiple-doped hierarchical porous carbons for superior zinc ion storage

Aqueous Zn-ion hybrid supercapacitors (ZHSCs) hold great potential as next-generation energy storage devices due to their low cost, excellent rate capability, long cycling life, and high safety. Heteroatom-doped hierarchical porous carbons (HD-HPCs) with integrated high specific surface area, multiscale pores, and abundant defects have been regarded as promising cathode materials for ZHSCs. However, the in situ architecture of HD-HPCs with these multiple advantages via a sustainable and controllable method remains an arduous challenge. Herein, a novel molecular engineering strategy was proposed for the in situ construction of N/P/O-doped HD-HPCs via the direct carbonization of multiple-heteroatom-rich hypermolecules. Such a strategy has multiple advantages, including the exclusion of pore-making techniques, activation agents, templates, and complicated and hazard washing processes, demonstrating its green and sustainable properties. The highly active multiple-heteroatom-rich hypermolecular precursors contributed to the formation of abundant micro/mesopores due to the self-abscission of heteroatoms and heteroatom-contiguous carbon atoms at high carbonization temperatures. Consequently, these active structural/compositional features endowed the optimal cathodes with outstanding storage capacities of 139.2 and 88.9 mA h g−1 at 0.5 and 20 A g−1 for aqueous ZHSCs, respectively. They also delivered a superior storage performance in quasi-solid ZHSCs (QS-ZHSCs) with a high specific capacity of 111.5 mA h g−1 at 0.5 A g−1. Superior energy/power densities and long cycling stability were also achieved for aqueous and QS-ZHSCs. The theoretical calculation confirmed the synergetic effects of multiple-atom doping on enhancing the electronic conductivity and reducing the energy barrier between Zn ions and carbon, which promote the Zn-ion adsorption capability. These findings shed fresh light on the straightforward manufacture of superior HD-HPCs for electrochemical energy storage.

Recent advances in the energy harvesting device technology using hetero-atom doped carbon nanotubes

Carbon nanotubes, graphene, and fullerene are forms of carbon finding widespread applications in numerous fields such as energy storage devices such as batteries and fuel cells, cosmetics, nano-electronics, nano-pharmaceuticals, nano-biotechnology, military devices and equipment, construction, coatings, cutting tools, catalysis and many more. The huge technological advancements, globalization, and never seen industrialization can gain more momentum only with the ready availability of sufficient energy resources and their harvesting. Fossil fuels remained one of the most important primary fuels all over the world and now the shift is towards more use of non-renewable energy resources. At the end of the last century, Svante Arrenius firstly proposed the interconnection between the increased concentration of gases such as CO2 in the atmosphere and the rise in the average temperature through global warming on our planet. This effect gets pronounced effects in various other natural cycles too as observed through various natural events in the 21st century. There are several global warming gases, but the principal emission associated with this change is carbon dioxide. Due to such environmental issues, emphasis is on the use of non-conventional energy sources such as solar, wind, geothermal, ocean, etc. Besides such sources, extensive work is going on the use of fuel cells and modern battery technology using carbon nanotubes (SWCNTs and MWCNTs). Presently, various advanced batteries and fuel cells are being developed using CNTs on an Industrial scale. In the last decade, efforts are taken to control the optical and electronic properties of CNTs incorporating hetero-atom (N, P, Si, S, Al, Ni, etc.) as a dopant for desired structural functionalization. The recent advancements in the field of energy harvesting devices (batteries or fuel cells) using hetero-atom-doped CNTs have been discussed here.

Green Synthesis of Near-Infrared Copper-Doped Carbon Dots from Alcea for Cancer Photothermal Therapy.

Heteroatom-doped carbon dots (CDs) with optical absorbance in the near-infrared (NIR) region can provide an opportunity for selective cancer photothermal therapy (PTT). Here, an eco-friendly, simple, cost-efficient, and one-step hydrothermal method was developed to synthesize copper-doped CDs (Cu-doped CDs). The Alcea extract as the carbon source was combined with CuSO4 as the dopant. Microscopic and spectroscopic analyses showed that spherical and monodisperse Cu-doped CDs (Cu-dCDs) with sizes below 10 nm have bright fluorescence with photoluminescence quantum yields of 11.1%. Cu-dCDs exhibited an excellent single absorbance peak at 800 nm and strong emission at 460 nm when excited at 370 nm. In vitro low cytotoxicity and the Cu-dCD-mediated cell PTT with the photothermal conversion efficiency (39.3%) show that cell internalization of Cu-doped CDs under an 800 nm NIR laser can induce cell thermal death.

Structural Characteristics and Electrochemical Performance of N,P-Codoped Porous Carbon as a Lithium-Ion Battery Anode Electrode.

Biomass-derived heteroatom-doped carbons have been considered to be excellent lithium ion battery (LIB) anode materials. Herein, ultrathin g-C3N4 nanosheets anchored on N,P-codoped biomass-derived carbon (N,P@C) were successfully fabricated by carbonization in an argon atmosphere. The structural characteristics of the resultant N,P@C were elucidated by SEM, TEM, FTIR, XRD, XPS, Raman, and BET surface area measurements. The results show that N,P@C has a high specific surface area (SBET = 675.4 cm3/g), a mesoporous-dominant pore (average pore size of 6.898 nm), and a high level of defects (ID/IG = 1.02). The hierarchical porous structural properties are responsible for the efficient electrochemical performance of N,P@C as an anode material, which exhibits an outstanding reversible specific capacity of 1264.3 mAh/g at 100 mA/g, an elegant rate capability of 261 mAh/g at 10 A, and a satisfactory cycling stability of 1463.8 mAh/g at 1 A after 500 cycles. Because of the special structure and synergistic contributions from N and P heteroatoms, the resultant N,P@C endows LIBs with electrochemical performance superior to those of most of carbon-based anode materials derived from biomass in the literature. The findings in this present work pave a novel avenue toward lignin volarization to produce anode material for use in high-performance LIBs.

Unique Spindle-Like Bismuth-Based Composite toward Ultrafast Potassium Storage.

Bismuth (Bi)-based materials have attracted great attention as anodes in potassium ion batteries (PIBs) for their high theoretical capacity and suitable voltage range. Herein, the authors report a unique spindle-like structured Bi@N-doped carbon composite (SPB@NC) consisting of interconnected nano-Bi coated heteroatom-doped hard carbon layer via an interesting insitu carbon thermal reduction method. The special interconnected Bi nanoparticles gradually form porous structure with ample inner voids for accommodating volume variations while the N-doped carbon layer not only keeps the electrode stable, but also contributes to rapid electron/ion transfer. As a result, such a robust framework endows SPB@NC fast potassium storage with outstanding capacity of 276.5mAhg-1 at 30Ag-1 (i.e., 1min for discharge/charge) and durable cycling performance of 299.3mAhg-1 at 5Ag-1 after 2000cycles. Notably, a full cell assembled with potassium vanadate cathode is promising for practical applications. A series of exsitu techniques reveals the in-depth potassium storage mechanism and kinetics reactions. This work illuminates helpful insights into Bi-based anodes for PIBs.

Hierarchical FeS<sub>2</sub>@FeS<sub>2</sub>@N,S-C hollow nanocubes for lithium storage

<p indent="0mm">With the increasingly prominent problems of energy shortage and environmental pollution, the requirement for high-efficiency energy storage devices is becoming more urgent. Lithium-ion batteries (LIBs) are commonly used in portable electronic devices, such as laptops, mobile phones. However, their limited performances cannot meet the demands of ultrahigh energy density and safety in the fields of new energy vehicles and energy storage systems. The development and application of novel anode materials can increase the capacity of LIBs. Transition metal sulfides (TMSs) with ultrahigh theoretical capacity and chemical stability present bright application prospects. Among them, iron sulfide (FeS_{<italic>x</italic>}) is regarded as one of the most promising anode materials due to its abundant reserves and environmental friendliness. However, the shortcomings of large volume expansion during cycling severely hinder the application of FeS_{<italic>x</italic>}<italic> </italic>and other TMSs. Designing TMS anode materials with special structures and combining them with carbon-based materials can effectively improve their electrochemical performance. Constructing nanosized TMSs with a hierarchical hollow structural property is a common strategy to increase their cycling stability. The abundant free volume inside the hollow structure can serve as a buffer space for TMSs with severe volume expansion, greatly reducing the structural fracture phenomenon. The internal free volume is also conducive to the electrolytic penetration into the composites. In addition, the dense nanosheets on the surface enable the active materials to fully contact the electrolyte, and subsequently, more reaction sites are generated for the electrochemical reactions. Combining amorphous carbon with TMSs can increase the dispersity of composites and reduce the presence of agglomerated structures. The amorphous carbon layer can serve as a stable interface for electrochemical reactions, which is beneficial for maintaining high coulombic efficiency and structure retention during cycling. The disordered structures and defects inside the amorphous carbon layer can accelerate the transport of the electrolyte and Li⁺ ions. Moreover, the amorphous carbon layers can also provide a structural support network and electronic conduction paths for TMSs, thereby improving the electrochemical performance of composites. Polydopamine (PDA) demonstrates special “viscosity,” which can coat almost any material’s surface under a weak alkaline condition. After carbonization, PDA is carbonized into an amorphous carbon layer with nitrogen doping, and the increased carbon interlayer spacing and defects can serve as additional active sites for lithium storage. In this study, the hierarchical FeS₂@FeS₂@N,S-C hollow nanocubes are successfully synthesized by a series of solvothermal, PDA <italic>in-situ</italic> polymerization, and high-temperature vulcanization processes. The inner hierarchical hollow FeS₂ is encapsulated in the heteroatom-doped carbon layer and in LIBs; the fabricated composites with a special structural property demonstrate improved electrode reaction kinetics. The results show that the discharge capacities of FeS₂@FeS₂@N,S-C are 505.6, 472.2, and 360 mAh/g at 0.2, 0.5, and <sc>2 A/g,</sc> respectively. Moreover, the reversible capacity of 492.1 mAh/g is maintained after 500 cycles at <sc>1 A/g,</sc> and the structure remains intact after cycling. The excellent electrochemical performance of FeS₂@FeS₂@N,S-C can be attributed to the heteroatom-doped carbon layer coating the hierarchical hollow structure and the synergistic effect of multiple components.