Dual-doped Porous Carbon Research Articles

DFT-guided synthesis of N, B dual-doped porous carbon from saccharina japonica for enhanced oxygen reduction catalysis.

The oxygen reduction reaction (ORR) is a crucial determinant of the energy transformation capacity of fuel cells. This study investigates the performance of N and B dual-doped carbon in ORR. Six models using density functional theory (DFT) are developed to compare the performance of different doping strategies. A highly efficient dual-doped carbon ORR catalyst (S-850-1) is synthesized from Saccharina japonica, containing 4.54 at% N and 1.05 at% B atom. Electrochemical analysis reveals that S-850-1 significantly outperforms the nitrogen mono-doped carbon S-850, exhibiting a higher half-wave potential of 0.861V and a greater limited current density of -5.60mAcm⁻2, compared to S-850's 0.838V and -5.24mAcm⁻2. Furthermore, S-850-1 surpasses the performance of 20% Pt/C, demonstrating enhanced durability and exceptional resistance to CO and methanol. The 1.40V open circuit voltage produced by S-850-1 when integrated into a Zn-air battery can power an LED light. Both theoretical and practical evaluations validate the excellent ORR performance of nitrogen and boron dual-doped carbon, as evidenced by the agreement between the electrochemical results and DFT calculations. This work not only extends the range of ORR catalysts derived from biomass but also provides guidance on creating and producing affordable, effective catalysts that utilize natural resources.

Honeycomb-like N, S dual-doped porous carbons derived from pomelo peel by effective exogenous doping strategy for supercapacitor electrodes

Biomass has emerged as a pivotal precursor to synthesize supercapacitor electrode materials owing to its low-cost and plentiful resources. The optimization of heteroatoms and porous structures is believed to be a viable method to enhance the electrochemical properties of biomass-generated carbons. Herein, pomelo peel as a precursor using KOH as an activator and heteroatom dopants (urea and sodium sulfide) was successfully converted into N, S dual-doped porous carbons under the high temperature. The effective exogenous doping strategy realizes a high abundance of N/S heteroatoms, and KOH chemical activation promotes the development of nanopores and interconnected porosities. The resultant carbon CNS-800 with a high specific surface area of 1823.8 m2 g−1 and rich heteroatoms of N (2.51 wt%) and S (1.36 wt%) anticipately exhibits the outstanding electrochemical properties, including the excellent specific capacitance of 329.2 F g−1 at 1 A g−1 in a three-electrode (3E) system and the superb capacitance retention rate of 74.12 %. The fabricated CNS-800-based symmetric two-electrode (2E) supercapacitor demonstrates a good capacitance of 243.7 F g−1 and excellent cycling stability, as well as a superb energy density of 14.3 Wh kg−1. This work provides a compelling and cost-effective approach to transform biomass waste like pomelo peels into high-performance electrodes for supercapacitors.

Metal organic framework derived heteroatom doped porous carbon nanocubes enable efficient charge storage in a lithium-ion capacitor

Lithium-ion capacitors (LICs) are regarded as one of the promising technologies towards realizing energy & power dense energy storage systems. However, their energy densities at higher power densities are still limited due to the discrepancy between electrode kinetics of capacitor-like cathode and battery-like anode. Developing carbon materials with well-defined structures, porosity to match the chemical kinetics between electrodes are the major challenges to overcome. In the present work, we have devised a strategy to fabricate S, N dual-doped porous carbon nanocubes (S, N-PCNs) using zeolitic imidazole framework (ZIF)-8 precursors, and employed the PCNs as anode material in LICs. With its well-defined structure, hierarchical porous nature, and abundant heteroatom presence (1.9 % S, 16.2 % N), the pre-lithiated S, N-PCNs based anode has offered a greatly improved reversible storage capacity of ∼930 mAh g−1 at 0.1 A g−1 along with an impressive rate capability and cycling life. When S, N-PCNs anode is paired with activated carbon cathode, the 4 V dual-carbon LIC yields an energy density as high as 120.24 Wh kg−1 and 10.2 kW kg−1 of power density with a good cycle stability of 90.6 % after 5000 charge-discharge cycles. This work would open new scopes of exploring metal-organic framework derived heteroatom-doped porous carbons to make metal-ion capacitors more efficient.

A Nitrogen/Oxygen Dual-Doped Porous Carbon with High Catalytic Conversion Ability toward Polysulfides for Advanced Lithium–Sulfur Batteries

Lithium–sulfur batteries (LSBs) have attracted widespread attention due to their high theoretical energy density and low cost. However, their development has been constrained by the shuttle effect of lithium polysulfides and their slow reaction kinetics. In this work, a nitrogen/oxygen dual-doped porous carbon (N/O-PC) was synthesized by annealing the precursor of zeolitic imidazolate framework-8 grown in situ on MWCNTs (ZIF-8/MWCNTs). Then, the N/O-PC composite served as an efficient host for LSBs through chemical adsorption and providing catalytic conversion sites of polysulfides. Moreover, the interconnected porous carbon-based structure facilitates electron and ion transfer. Thus, the S/N/O-PC cathode exhibits high cycling stability (a stable capacity of 685.9 mA h g−1 at 0.2 C after 100 cycles). It also demonstrates excellent rate performance with discharge capacities of 1018.2, 890.2, 775.1, 722.7, 640.4, and 579.6 mAh g−1 at 0.2, 0.5, 1.0, 2.0, 3.0, and 5.0 C, respectively. This work provides an effective strategy for designing and developing high energy density, long cycle life LSBs.

Waste tobacco-derived N, P dual-doped porous carbon loaded with heterostructured CoFe/CoFe2O4 nanoparticles for efficient oxygen electrocatalysis and Zn-air batteries

Bifunctional oxygen reduction/oxidation reaction (ORR/OER) electrocatalysts can be derived from waste biomass for implementing rechargeable Zn–air batteries, which not only turns waste into wealth, but also provides a novel approach for solving the energy crisis and promoting environmental restoration. Herein, heterostructured CoFe/CoFe2O4 nanoparticles grown on waste tobacco-derived N,P-co-doped carbon (CoFe/CoFe2O4@PNC) are constructed. Benefiting from the accelerated electron transfer due to the synergistic effect of CoFe and CoFe2O4 along with the enlarged active area owing to N,P-codoping, the CoFe/CoFe2O4@PNC electrocatalysts exhibit remarkable OER/ORR activity, reaching a half-wave potential of 0.86 V for ORR solution and driving 10 mA cm−2 by OER overpotential of 360 mV in 1.0 M KOH. Moreover, the zinc-air battery assembled with CoFe/CoFe2O4@PNC can reach a power density of 141.5 mW cm−2 and exhibit impressive durability for exceeding 300 h, which are superior to the power density and stability of zinc-air batteries assembled with precious metal-based materials. This work opens up new possibilities for preparing advanced ORR/OER catalysts for efficient Zn-based batteries.

Air-engaged synthesis of yeast biomass-derived porous O, P-codoped biochar as metal free catalyst towards water decontamination

Facile and sustainable preparation of effective metal-free catalysts using natural biomass as a feedstock is essential but challenging for peroxymonosulfate activation in degrading organic pollutants in wastewater. In this study, we develop an air-engaged pyrolysis method to successfully prepare O, P dual-doped porous carbon material (Yeast-T) using biomass yeast as a feedstock. Among the samples, Yeast-650 exhibits the highest performance in activating peroxymonosulfate towards the destruction of methyl orange, achieving a removal efficiency of 98 % in 30 min and a rate constant of 0.226 min-1. The non-radical pathway, with singlet oxygen as the active substance, dominates the destruction of methyl orange over the Yeast-650/peroxymonosulfate system. Based on the detected intermediates, four possible pathways for methyl orange degradation by the Yeast-650/peroxymonosulfate system are unveiled. The toxicity analysis of the degradation products was evaluated by calculating and comparing the radicle length of mung bean in different solutions and the germination of wheat seeds in different solutions. This study presents a simple and feasible air-mediated synthetic method for high-performance metal-free peroxymonosulfate activators in the removal of organic pollutants.

Nitrogen-phosphorus dual-doped auricularia auricula porous carbon as host for Li-S battery.

A nitrogen-phosphorus dual-doped porous spore carbon (NP-PSC) positive electrode matrix was prepared using native auricularia auricula as solid medium based on the principle of biomass rot. Yeast was introduce and cultured by the auricularia auricula solid medium. The freeze-drying and carbonization activation processes made the materials present a three-dimensional porous spore carbon aerogel properties. Yeast fermentation transformed auricularia auricula from blocky structure to porous structure and introduced nitrogen-phosphorus dual-doping. The physical and chemical properties of the prepared materials were characterized in detail. Electrochemical performance of NP-PSC in Li-S batteries was systematically investigated. Porous structure and heteroatom-doping improved the electrochemical performance, which is much superior to conventional activated carbon materials.

Disclosing the intrinsic nature of efficient removal of antibiotics in N/S dual-doped porous carbon-based materials: The manipulation of internal electric field

N/S co-doping has emerged as a prevailing strategy for carbon-based adsorbents to facilitate the antibiotic removal efficiency. Nevertheless, the underlying interplay among N, S, and their adjacent vacancy defects remains overlooked. Herein, we present a novel in situ strategy for fabricating pyridinic-N dominated and S dual-doped porous carbon adsorbent with rich vacancy defects (VNSC). The experimental results revealed that N (acting as the electron donor) and S (acting as the electron acceptor) form an internal electric field (IEF), with a stronger IEF generated between pyridinic-N and S, while their adjacent vacancy defects activate carbon π electrons, thus enhancing the charge transfer of the IEF. Density functional theory (DFT) calculations further demonstrated that the rich charge transfer in the IEF facilitated the π-π electron donor-acceptor (EDA) interaction between VNSC and tetracycline (TC) as well as norfloxacin (NOR), and thus is the key to adsorption performance of VNSC. Consequently, VNSC exhibited high adsorption capacities toward TC (573.1 mg g−1) and NOR (517.0 mg g−1), and its potential for environmental applications was demonstrated by interference, environmentally relevant concentrations, fixed-bed column, and regeneration tests. This work discloses the natures of adsorption capacity for N/S dual-doped carbon-based materials for antibiotics.

A Hybrid Hydrogel Approach for the Design of N, S Dual-Doped Porous Carbon Electrocatalyst for Oxygen Reduction Reaction

A Hybrid Hydrogel Approach for the Design of N, S Dual-Doped Porous Carbon Electrocatalyst for Oxygen Reduction Reaction

Metal-Organic-Framework-Derived Bromine and Nitrogen Dual-Doped Porous Carbon for CO2 Photocycloaddition Reaction.

The cycloaddition of CO2 with epoxides driven by light irradiation is an intriguing approach to preparing cyclic carbonates. However, it remains a great challenge to achieve high photocatalytic efficiency in the absence of a cocatalyst. Herein, we explored a metal-organic-framework (MOF)-templated pyrolysis strategy to prepare uniform bromine ions/nitrogen-codoped carbon materials (Br-CN) as low-cost photocatalysts for CO2 cycloaddition. The optimal catalyst Br-CN-1-550 can be used as a photocatalyst to catalyze CO2 cycloaddition, remarkably reducing the energy consumption. As a result of its benefits of high photothermal efficiency and rich nucleophilic sites (Br ions), BN-CN-1-550 affords a 9 times higher yield of 4-(chloromethyl)-1,3-dioxolan-2-one than that of the ZIF-8-derived CN under cocatalyst-free conditions and light irradiation (300 mW·cm-2 full-spectrum irradiation, 10 h). This strategy provides a cost-effective way to obtain cyclic carbonate under cocatalyst-free conditions.

Boosting the oxygen reduction activity of non-metallic catalysts via geometric and electronic engineering through nitrogen and chlorine dual-doping.

The development of heteroatom dual-doped porous carbon frameworks with uniform doping is highly desirable for achieving highly efficient oxygen reduction reaction (ORR) activity, due to their tunable chemical and electronic structures. Herein, porous covalent triazine-based frameworks (CTFs) incorporating nitrogen/chorine dual-doped porous carbon networks were fabricated by selecting 1,3-bis(4-cyanophenyl) imidazolium chloride as a building block, in a facile and controllable way via a bottom-up strategy. The resulting nitrogen/chorine dual-doped catalyst CCTF-700 exhibits excellent ORR performance with a more positive onset and half-wave potential (0.85 V vs. RHE), higher diffusion-limited current density and significantly improved stability in comparison with the benchmark commercial 20 wt% Pt/C catalyst. It is worth mentioning that CCTF-700 shows one of the best ORR performances among all the reported metal-free electrocatalysts under alkaline conditions. This work paves the way for a controllable and reliable strategy to craft highly efficient heteroatom dual-doped carbon catalysts for energy conversion.

High-performance supercapacitors enabled by N/S dual-doped porous carbon and DMO-regulated electrolyte

The demand for high-performance supercapacitors exceeds the capabilities of pristine carbon materials and traditional electrolytes. To address this gap, we prepared a petal-like multicyclic polycondensate precursor (PCDP) using Knoevenagel reaction and amine/aldehyde condensation between 3-aminorhodanine and p-phthalaldehyde. The subsequent activation of PCDP by KOH and carbonization at various temperatures (600–900 °C) were employed to produce N/S-dual doped porous carbon (N/S-DDPCs) for use as electrode materials. For N/S-DDPC8 carbonized at 800 °C, the specific surface area measured as the highest at 2047 m2 g−1 with a significant number of interconnected micro/mesoporous structures and higher N and S contents of 3.57 % and 2.31 %, respectively. Furthermore, Zn(CF3SO3)2 aqueous electrolyte was developed using dimethyl oxalate (DMO) to regulate and improve the electrochemical performance of the N/S-DDPCs while also providing better stability. In comparison to the conventional Zn(CF3SO3)2 electrolyte, the utilization of N/S-DDPC8 in DMO-regulated Zn(CF3SO3)2 electrolyte resulted in a noteworthy enhancement in energy density and power density, soaring to 36.4 Wh kg−1 from 11.7 Wh kg−1 and to 642 W kg−1 from 250 W kg−1 at a current density of 0.5 A g−1, respectively. It is particularly noteworthy that N/S-DDPC8-DMO-D can maintain 100 % specific capacitance even after 10,000 cycles, demonstrating its high-level electrochemical consistency. In brief, the porous N/S-DDPCs and DMO-regulated electrolyte created in this study serve as a valuable guide for boosting the electrochemical performance of supercapacitors.

Energy-Dense Zinc Ion Hybrid Supercapacitors with S, N Dual-Doped Porous Carbon Nanocube Based Cathodes.

Zinc ion hybrid supercapacitors (ZIHSCs) are truly promising as next-generation high-performance energy storage systems because they could offer high energy density like batteries while exhibiting high power output and long cycle life traits of supercapacitors. The key point of constructing a high-performance ZIHSC is to couple the Zn anode with an appropriate cathode material, which has high theoretical capacity, cost-effectiveness, and intrinsic safety features. In this work, we have demonstrated the potentiality of S, N co-doped porous carbon nanocubes (S, N-CNCs) as a cathode material for devising a ZIHSC with excellent energy density and cycle life. The S, N-CNCs are prepared from a zeolitic imidazolate framework (ZIF)-8 precursor via a simultaneous pyrolyzing-doping strategy in an inert atmosphere. Resultant CNCs are monodisperse with an average size of around 65 nm and porous in nature, with uniform N and S doping throughout the structure. Benefitted from such hierarchical porous architecture and the presence of abundant heteroatoms, the assembled ZIHSC with S, N-CNC as the cathode and Zn-foil as the anode in a ZnSO4 aqueous electrolyte could reach a specific capacity as high as 165.5 mA h g-1 (331 F g-1) at 1 A g-1, which corresponds to a satisfactory energy density of 148.9 W h kg-1 at the power density of 900 W kg-1. The ZIHSC has displayed a good cycle stability with more than 70% capacity retention after 10,000 charge-discharge cycles. Furthermore, to verify the practical feasibility of such a cathode material, an aqueous 3D Zn@Cu//S, N-CNC full-cell device is fabricated, which has demonstrated a satisfactory specific capacity (49.6 mAh g-1 at 0.25 A g-1) and an impressive energy density (42.2 Wh kg-1 with 212.2 W kg-1). Full ZIHSC devices are also found to be efficient in powering light-emitting diodes, further substantiating their feasibility in next-generation energy storage applications.

DFT-guided design and synthesis of sea cucumber-derived N, S dual-doped porous carbon catalyst for enhanced oxygen reduction reaction and Zn-air battery performance

DFT-guided design and synthesis of sea cucumber-derived N, S dual-doped porous carbon catalyst for enhanced oxygen reduction reaction and Zn-air battery performance

Enhanced conversion of superoxide radical to singlet oxygen in peroxymonosulfate activation by metal-organic frameworks derived heteroatoms dual-doped porous carbon catalyst

The activation of persulfate technology using carbon-based materials doped with heteroatoms has been extensively researched for the elimination of refractory pollutants in wastewater. In this study, metal-organic frameworks were utilized as precursors to synthesize P, N dual-doped carbon material (PNC), which was employed to activate peroxymonosulfate (PMS) for the degradation of tetracycline hydrochloride (TCH). The results demonstrated a 90.2% removal efficiency of total organic carbon within 60 min. The significant increase of surface defects on the nitrogen self-doped porous carbon materials anchored with phosphorus promoted the conversion of superoxide radical to singlet oxygen during PMS activation, which was identified as the key active species of PNC/PMS system. Additionally, the enhanced direct electron transfer also facilitated the degradation of TCH. Consequently, TCH was successfully degraded into nontoxic and harmless inorganic small molecules. The findings of this research provide valuable insights into improving the performance of heteroatom-doped carbon materials for pollutant degradation by activating PMS and transforming the non-radical pathway. The results highlight the potential of metal-organic frameworks derived heteroatoms dual-doped porous carbon catalysts for the development of advanced treatment technologies in wastewater treatment.

Enhancing Sulfur Redox Conversion of Active Iron Sites by Modulation of Electronic Density for Advanced Lithium-Sulfur Battery.

Despite lithium-sulfur (Li-S) batteries possessing ultrahigh energy density as great promising energy storage devices, the suppressing shuttle effect and improving sulfur redox reaction (SROR) are vital for their practical application. Developing high-activity electrocatalysts for enhancing the SROR kinetics is a major challenge for the application of Li-S batteries. Herein, single-molecule iron phthalocyanine species are anchored on the N and P dual-doped porous carbon nanosheets (Fe-NPPC) via axial Fe-N coordination to optimize the electronic structure of active centers. The Fe-NPPC can promote the catalytic conversion of polysulfides by modulation of the electronic density in active moieties, endowing the Li-S battery with a high reversible capacity of 1023 mAh g-1 at 1 C as well as an ultralow capacity decay of 0.035% per cycle over 1500 cycles. Even with a high sulfur loading of 7.1mg cm-2 , the Li-S battery delivers a high areal capacity of 4.8 mAh cm-2 after 150 cycles at 0.2 C. With further increasing the sulfur loading to 9.2mg cm-2 , an excellent areal capacity of up to 9.3 mAh cm-2 is obtained at 0.1 C.

Fabrication of dual heteroatom-doped graphitic carbon from waste sponge with “killing two birds with one stone” strategy for advanced aqueous zinc–ion hybrid capacitors

Emerging aqueous zinc–ion hybrid capacitors (AZICs) are considered a promising energy storage because of their superior electrochemical performance. The pore structure, suitable heteroatom content, and graphitization degree (GD) of carbon-based cathodes significantly influence the electrochemical performance of AZICs. The N, S dual-doped porous graphitic carbon materials (LC-750) with the combined characteristics of high GD (1.11) and large specific surface area (1678.38 m2 g−1) are successfully developed by a facile “killing two birds with one stone” strategy using K3Fe(C2O4)3·3H2O as the activating and graphitizing agent, and waste sponge (WS) and coal tar pitch (CTP) as the heteroatom and carbon resource, respectively. Results show that the LC-750 cathode displays high capacities of 185.3 and 95.2 mAh g−1 at 0.2 and 10 A g−1. Specifically, the assembled LC-750//Zn capacitor can offer a maximal energy density of 119.5 Wh kg−1, a power density of 20.3 kW kg−1, and a capacity retention of 87.8% after 15,000 cycles at 10 A g−1. Density functional theory simulations demonstrate that N and S dual-doping can promote the adsorption kinetics of Zn ions. This design strategy is a feasible and cost-effective method for the preparation of dual heteroatom-doped graphitic carbon electrodes, which enables recycling of WS and CTP into high-valued products.

Fe and N dual doped porous carbon derived from waste biomass as an effective catalyst for oxygen reduction reaction

Developing a cathode catalyst with low-cost, facile preparation process and good electrocatalytic performance for oxygen reduction reaction (ORR) is critical to the application of fuel cell. In this study, a feasible approach for the sustainable synthesis of Fe and N dual-doped porous biomass-derived carbon catalyst (Fe-NPC) was demonstrated, with passion fruit peels as the carbon precursor, FeCl3 and melamine as the activators. Fe-NPC exhibits hierarchically porous structure with large specific surface area (1456.5 m2g−1), and the Fe, N distribute homogeneously in the entire architecture of Fe-NPC. The material shows comparable electrocatalytic activity (E1/2 = 0.872 V) and superior stability for ORR to commercial Pt/C (20 wt%) in alkaline electrolyte.

Coffee grounds derived sulfur and nitrogen dual-doped porous carbon for the cathode material of lithium‑sulfur batteries

Coffee grounds derived sulfur and nitrogen dual-doped porous carbon for the cathode material of lithium‑sulfur batteries

Scrutinizing Synergy and Active Site of Nitrogen and Selenium Dual-Doped Porous Carbon for Efficient Triiodide Reduction

Electrocatalytic interconversion of iodide/triiodide is the key for state-of-the-art iodine-involved energy technologies, which is challenged by understanding the structure–activity relationship of the smart electrocatalysts with tuned active sites. Herein, active-site-enriched N,Se-co-doped porous carbon, denoted as NSeC, is crafted by a two-step approach of the template method and chemical doping. X-ray photoelectron spectroscopy and synchrotron X-ray absorption spectroscopy measurements substantiate the incorporation of extrinsic N and Se species into the carbon matrix. Raman spectroscopy reveals that the defect of densities within NSeC can be finely tuned by adjusting the doping temperature. The NSeC sample made at 900 °C shows a robust durability and a high electrocatalytic activity toward the triiodide reduction reaction with a relatively small charge-transfer resistance (0.75 Ω cm2) in parallel with a short electron lifetime (252.2 μs) participating in the triiodide reduction. Density functional theory calculations reveal that the high catalytic activity of the NSeC is due to the combined impacts, i.e., the synergy between N and Se species that helps to manipulate the adsorption process of iodine atoms and the active sites formed by the carbon atoms adjacent to quaternary N and Se atoms at the armchair edges. This work offers insights into both the design of efficient metal-free catalysts and the synergy of dual doping for efficient iodine-involved electrocatalysis for energy devices.