Co-doped Carbon Materials Research Articles

A novel one-step calcination tailored single-atom iron and nitrogen co-doped carbon material catalyst for the selective reduction of CO2 to CO

Single atom Fe-N-C based electrocatalysts are the most promising candidates for industrial applications of reduction of CO2. However, preparation of Fe-N-C catalyst often involves complex procedures and expensive precursors/reagents. In this work, we developed a novel one-step calcination method to tailor single-atom Fe-N-C catalyst for CO2 reduction. The maximum Faraday efficiency of CO (FECO) and the Tafel slope of Fe-N-C material was 73% and 68 mv dec−1, respectively, which was much higher than that of the pristine N-C material. The CO2 electroreduction products were CO and H2 with a total Faraday efficiency of 100%, indicating that the Fe-N-C material had high selectivity on CO2 reduction to CO. The designed Fe-Nx structure on the Fe-N-C material acted as a highly active site, and the abundant functional groups and microporous structure resulted in high catalytic performance of Fe-N-C material. This work demonstrates that the tailored single-atom Fe-N-C catalyst by one-step calcination has broad application prospects in the electrochemical reduction of CO2.

Synthesis of Fe-Nx site-based iron-nitrogen co-doped biochar catalysts for efficient removal of sulfamethoxazole from water by activation of persulfate: Electron transfer mechanism of non-free radical degradation

Fe-N co-doped carbon materials (Fe-NC) have drawn increasing attention in advanced oxidation due to their unique structure and significant promise in heterogeneous catalysis. Herein, a Fe-N co-doped biochar catalyst was prepared by a simple pyrolysis method and was applicated to activate persulfate (PS) for the degradation of sulfamethoxazole (SMX) in wastewater. The catalytic performance of Fe-NBC was proportional to the pyrolysis temperature, and Fe-NBC-800 exhibited excellent PS activation performance with larger specific surface area (254.3 m2/g), higher defect (ID/IG = 1.04). Fe-NBC-800 exhibits high stability and reusability over multiple cycles, high catalytic activity over a wide pH range of 3–9 and good tolerance to inorganic anions. The introduction of nitrogen and iron into the carbon lattice leads to a redistribution of charge density in graphitic carbon, enhancing the interaction of PS with Fe-NBC-800 surface to form surface complexes and promoting charge transfer. Five major SMX degradation pathways are proposed, including the oxidation of nitro on the aniline ring, the breakage of S-N bond and the ring opening of isoxazole ring. This study provides new ideas for the design of Fe-NC catalysts in the field of advanced oxidation.

Facile synthesis of mesoporous carbon materials with a three-dimensional ordered mesostructure and rich FeNX/C-S-C sites for efficient electrocatalytic oxygen reduction

Incorporation of sulfur (S) atoms into iron/nitrogen co-doped (FeNX) carbon materials is attractive for developing efficient electrocatalysts for the oxygen reduction reaction (ORR). Synthesis of such materials with suitable pore structures and rich active sites are important to improve the ORR performance. In this study, we demonstrate the facile synthesis of novel N/S co-doped ordered mesoporous carbon materials with a three-dimensional (3D) ordered bicontinuous cubic mesopore structure and rich FeNX and carbon-sulfur-carbon (C-S-C) sites (denoted as FeNX@NSOMCs) using the solvent-free nanocasting method. The 3D ordered bicontinuous cubic mesopore structure is replicated in the FeNX@NSOMCs from the mesoporous silica hard template KIT-6. The uniform N/S dopants in the carbon matrix is derived from the confined pyrolysis of a single amino acid methionine (Met). The creation of the FeNX sites is enabled by using anhydrous FeCl3 as the precursor. The absence of solvent and the coordination between FeCl3 and Met can reduce metal hydrolysis and aggregation, reduce N loss, and thus promote the formation of FeNX sites. The FeNX@NSOMCs possess high surface areas (830–938 m2/g), large pore volumes (0.97–1.36 cm3/g), disordered macropores and ordered mesopores (3.5–3.6 nm), and well-graphitized carbon walls. They are promising for ORR. The represent sample shows superior performance under alkaline conditions, achieving a high half-wave potential of 0.9 V, a high kinetic current density of 4.2 mA/cm2, a low Tafel slope of 55.3 mV/dec, a near four-electron process with a low H2O2 yield and a high stability. A comparative study using various control samples reveals that the FeNX sites, the S doping and the ordered mesopore structure are crucial to achieve the high ORR performance.

Joule-heating Pyrolysis-derived Fe, N Co-doped Carbon and Its Performance in Direct Peroxide-Peroxide Fuel Cells

The traditional electric furnace pyrolysis to produce heteroatom doped carbon faces the time-consuming issue due to the fixed size of furnace chamber and indirect heat transfer. Herein a fast Joule-heating pyrolysis method, viz., powering on the C, N, Fe-containing, conductive polyaniline precursor at fixed direct current (DC) voltage for a specific time, is put forward. The polyaniline precursor begins to decompose thermally when being powered with a DC voltage of 5.0 V upwards. In the pyrolysis products, Fe and N co-doping of carbon material leads to C–N bonding and C-Fe bonding in a certain way. The direct peroxide-peroxide fuel cell (DPPFC) with the optimal Fe, N codoped carbon material as anode and cathode can generate an open circuit voltage of 0.85 V and a peak power density of 29.7 mW cm−2 in ambient temperature, which is highly competitive compared with other DPPFCs with anode and/or cathode made of noble metals.

Tuning electron delocalization and surface area in COFs derived N, B co-doped carbon materials for efficient selective hydrogenation of nitroarenes

Metal-free carbon catalysts with excellent conduction performance have drawn much research attention in reduction reactions. Herein, a N, B co-doped carbon catalyst with high pyrrolic N proportion (35.75%) and excellent surface area (1409 m2/g) was successfully prepared via carbonizing covalent organic framework materials (COFs) containing N and B atoms assisted by ZnCl2 molten salt. The presence of ZnCl2 maintains the micropore structure of COFs to provide high specific surface areas and abundant lattice defects for carbon materials. In addition, electron-withdrawing B heteroatom further facilitates the formation of pyrrolic N at defect sites by modifying the electronic structure of carbon network. The tuning of surface areas and active N species in carbon catalysts successfully improve the selective hydrogenation of nitrobenzene to aniline. The optimized carbon material exhibits excellent nitrobenzene conversion (99.9%) and aniline selectivity (>99%) within 15 min, as well as excellent substrate suitability. This work provides a certain guiding for the design and application of metal-free catalysis.

MIL-88-Derived N and S Co-Doped Carbon Materials with Supplemental FeSx to Enhance the Oxygen Reduction Reaction Performance

To overcome the drawbacks of the single N-doped carbon materials, the further development of dual-heteroatoms (N and S) co-doped electrocatalysts is highly anticipated. Herein, N, S-doping and Fe-based carbon materials were synthesized by pyrolyzing a metal–organic framework (MIL-88) with the addition of N-/N, and S-containing ligands (chitosan and L-Cysteine) in the case of iron salt. The resulting electrocatalyst heat-treated at 850 °C (FeNSC-850) displays superior oxygen reduction reaction (ORR) performances to MIL-88-850, with an overall electron transfer number of 3.97 and a minor yield of HO2-% (<2.6%). In addition to the comparable activity to commercial Pt/C in catalyzing the ORR in alkaline solution, the FeNSC-850 also shows higher stability, with a slight decline in half-wave potential (∆E1/2 = 15 mV) after 5000-cycle scanning of cyclic voltammetry. In view of the multiple Fe-based active sites, the additional S doping within FeNSC-850 creates more FeSx active sites for boosting the ORR performances in alkaline solution.

One-Step Synthesis of High-Performance N/S Co-Doped Porous Carbon Material for Environmental Remediation

Potassium thiocyanate (KSCN), a highly efficient “three birds with one stone” activator, might work with inorganic activators to produce excellent N/S co-doped porous carbon (NSC) materials for environmental remediation. However, the effects of inorganic activators on cooperative activation are unclear. As a result, the influence of inorganic activators on the synthesis of NSC materials was investigated further. This study shows that the surface areas of the NSC materials acquired through cooperative activation by potassium salts (KOH or K2CO3) were considerably higher than those acquired through KSCN activation alone (1403 m2/g). Furthermore, KSCN could cooperate with K2CO3 to prepare samples with excellent specific surface area (2900 m2/g) or N/S content. The as-prepared NSC materials demonstrated higher adsorption capability for chloramphenicol (833 mg/g) and Pb2+ (303 mg/g) (pore fitting, complexation). The research provides critical insights into the one-step synthesis of NSC materials with a vast application potential.

(Digital Presentation) Oxygen Reduction Reaction on Waste Tire Derived Carbon Material and Synthesized Non-Platinum Group Metal Catalysts in Alkaline Solution

Over the past decades, a considerable amount of work has been put into replacing expensive Pt in oxygen reduction reaction (ORR) catalysts for use in fuel cells, such as with Fe or Co and nitrogen co-doped carbon materials [1-3]. At the same time, a major environmental issue is the lack of adequate methods for repurposing or recycling waste tires. Herein, it was investigated whether waste tires could be used as a source of carbon for synthesizing ORR catalysts.To prepare the carbon support, waste tire granules were pyrolyzed at 1000 °C for three hours in Ar. This material was then used to synthesize four non-platinum-group metal (NPGM) catalysts via dry ball-milling [2] and wet synthesis [2, 3] methods. FeSO4∙7H2O or Co(NO3)2·6H2O salts and 2,2’-bipyridine were used as precursors. Wet synthesis required the precursors to be dissolved in water and mixed with the carbon material, after which the solution was dried. For the dry method, all precursors were mixed and ball-milled for one hour. The products of both synthesis methods were subsequently pyrolyzed at 800 °C for 1.5 h in Ar.All materials were characterized using HR-SEM, SEM-EDX, and nitrogen sorption methods. The materials were heterogeneous and contained additives commonly present in tires as constituents of tire filler materials or residual products of tire production (Si, S, Ca, and Zn). All materials exhibited low porosity and a rather low specific surface area (SBET = 92 to 150 m2 g-1).Electrochemical analyses were carried out in an O2 saturated 0.1M KOH solution using the rotating disk electrode method. Although the carbon support on its own did not show significant activity toward the ORR, the modified Co-N/C and Fe-N/C catalysts demonstrated substantially higher onset potentials (∆Eonset ~150 mV). The best electrochemical activity was achieved by the Co-N/C material synthesized using the wet method. These results show that waste tire-derived carbon materials can be used to successfully synthesize NPGM catalysts suitable for application in fuel cells. Acknowledgements This work was supported by PRG676 "Development of express analysis methods for micro-mesoporous materials for Estonian peat derived carbon supercapacitors" (1.01.2020- 31.12.2024), TK141 "Advanced materials and high-technology devices for sustainable energetics, sensorics and nanoelectronics" (1.01.2016−1.03.2023), and LLTKT20148 "Production of Polymer Electrolyte Membrane Fuel Cell" (10.02.2020−9.07.2021) References [1] F. Roncaroli, E. S. Dal Molin, F. A. Viva, M. M. Bruno, and E. B. Halac, Electrochimica Acta, 174, p. 66 (2015)[2] P. Teppor, R. Jäger, E. Härk, S. Sepp, M. Kook, O. Volobujeva, P. Paiste, Z. Kochovski, I. Tallo, and E. Lust, J. Electrochem. Soc., 167, 054513 (2020)[3] R. Jäger, P. E. Kasatkin, E. Härk, P. Teppor, T. Romann, R. Härmas, I. Tallo, U. Mäeorg, U. Joost, P. Paiste, K. Kirsimäe, and E. Lust, J. Electroanal. Chem., 823, p. 593 (2018)

(Digital Presentation) The Optimization of Polypyrrole Concentration to Synthesize Hollow Fe, Co, and Nitrogen Doped Carbon Spheres with Improved Oxygen Reduction Reaction Performance

Transition metal and nitrogen co-doped carbon materials (M-N-C, M=Fe, Co, Ni, etc.) have recently emerged as front runners to replace commercial Pt/C for the oxygen reduction reaction (ORR) due to their natural availability and excellent electrocatalytic activity. The development of M-N-C materials with optimized active sites using a secondary nitrogen source has attracted a lot of attention as ORR catalysts for their high activity and excellent durability. Polypyrrole (PPy) has become an attractive secondary nitrogen source for increased nitrogen doping and metal dispersion. Herein, we developed hollow Fe, Co, and nitrogen-doped carbon (H-FeCo-NC) spheres using the composites of metal-organic frameworks (MOFs) materials and PPy. Based on X-ray absorption fine spectroscopy analysis, X-ray photoelectron spectroscopy, and transmission electron microscopy, the active centers and the role of PPy for ORR catalytic performance are explored. The H-FeCo-NC not only displayed remarkable ORR performance in alkaline media, with a half-wave potential of 0.903 V, but also showed excellent stability and durability. The results outperformed the commercial Pt/C catalyst, demonstrating the potential of utilizing PPy for improved ORR performance.

Lonicerae flos-derived N, S co-doped graphitized carbon uniformly embedded with FeS2 nanoparticles as anode materials for high performance lithium ion batteries

Metal sulfides still face significant challenges in terms of large volume expansion and poor conductivity as anodes for lithium ion batteries. For the past few years, many researches have shown that the preparation of the composite of metal sulfide and heteroatom doped graphitized carbon with high conductivity has become an effective method to improve its lithium storage performance. In this work, FeS2 @N/S-C composite was successfully synthesized through homogeneously embedding FeS2 nanoparticles into N and S co-doped biomass-derived graphitized carbon, by using Lonicerae flos as carbon source and bio-template. It is worth noting that the introduction of Fe ions effectively enhances the graphitization degree of the N, S co-doped carbon material derived from Lonicerae flos, thus improves the conductivity and stability of the composite. At the same time, the uniform coating of highly conductive carbon effectively inhibits the growth and agglomeration of FeS2 nanoparticles during the process of charge and discharge. Therefore, the FeS2 @N/S-C electrode exhibits large lithium storage capacity, delivers a high capacity of 1259 mA h g−1 at 0.1 A g−1 after 100 cycles, and excellent long-term cycle performance at 1.0 A g−1 (528 mA h g−1 after 1000 cycles). These results indicate that the as-prepared FeS2 @N/S-C composite is a promising anode.

Nitrogen and phosphorus co-doped carbon for improving capacity and rate performances of potassium ion batteries

The carbon material is considered as the promising anode for potassium ion battery owing to the merits of wide source and structural robustness. However, the limited capacity and the slow kinetics limit the development of carbon materials. Herein, the porous nitrogen-and-phosphorus co-doped carbon material are prepared using the O2-NH3 reactive pyrolysis of cellulose with the additional phosphating treatment. As compared with the pristine carbon obtained by the direct pyrolysis of cellulose, the capacity of nitrogen-and-phosphorus co-doped carbon rises from 140 to 253 mAh g−1, and the capacity increases significantly even at high current density (from 16 to 76 mAh g−1 at 20 A g−1). Under the guidance of theoretical simulation, the enhancement of potassium storage capacity and kinetics is explored by combining spectral characterization and electrochemical research. On this basis, the synergistic effect of nitrogen and phosphorus co-doping can improve the potassium storage performance. This study has reference significant for heteroatom modification of carbon materials for potassium storage anodes.

Self-Templating Synthesis of N/P/Fe Co-Doped 3D Porous Carbon for Oxygen Reduction Reaction Electrocatalysts in Alkaline Media.

The development of low-cost, highly active, and stable oxygen reduction reaction (ORR) catalysts is of great importance for practical applications in numerous energy conversion devices. Herein, iron/nitrogen/phosphorus co-doped carbon electrocatalysts (NPFe-C) with multistage porous structure were synthesized by the self-template method using melamine, phytic acid and ferric trichloride as precursors. In an alkaline system, the ORR half-wave potential is 0.867 V (vs. RHE), comparable to that of platinum-based catalysts. It is noteworthy that NPFe-C performs better than the commercial Pt/C catalyst in terms of power density and specific capacity. Its unique structure and the feature of heteroatom doping endow the catalyst with higher mass transfer ability and abundant available active sites, and the improved performance can be attributed to the following aspects: (1) Fe-, N-, and P triple doping created abundant active sites, contributing to the higher intrinsic activity of catalysts. (2) Phytic acid was crosslinked with melamine to form hydrogel, and its carbonized products have high specific surface area, which is beneficial for a large number of active sites to be exposed at the reaction interface. (3) The porous three-dimensional carbon network facilitates the transfer of reactants/intermediates/products and electric charge. Therefore, Fe/N/P Co-doped 3D porous carbon materials prepared by a facile and scalable pyrolysis route exhibit potential in the field of energy conversion/storage.

Facile construction of a highly dispersed PdCo nanocatalyst supported on NH2-UiO-66-derived N/O co-doped carbon for hydrogen evolution from formic acid

Rational design of catalysts with a high activity and low cost is crucial but still challenging for formic acid (FA) as a hydrogen storage material. Herein, PdCo-bimetallic particles were evenly dispersed on N/O co-doped porous carbon, which is achieved through the one-step pyrolysis NH2-UiO-66 strategy. The evaluation test demonstrated that the prepared catalysts had high activity and selectivity for the decomposition of FA. The turnover frequency (TOF) of FA decomposition catalyzed by Pd4Co1/CN–O-800 at 30 °C was 2425 h−1 (TOF at 50 °C was 4587 h−1) and the selectivity of hydrogen was 100%. Structural characterizations combined with detailed theoretical calculation results reveal that the constructed N/O co-doped system endows the bimetallic catalyst with abundant catalytic sites and strong metal-support interaction, thereby achieving remarkable catalytic performance. The results provide ideas for the design of efficient FA dehydrogenation catalysts and offer theoretical guidance to N/O co-doped carbon materials.

Metal-Organic Framework-Derived Graphene Mesh: a Robust Scaffold for Highly Exposed Fe-N4 Active Sites toward an Excellent Oxygen Reduction Catalyst in Acid Media.

This study demonstrates a special ultrathin N-doped graphene nanomesh (NGM) as a robust scaffold for highly exposed Fe-N4 active sites. Significantly, the pore sizes of the NGM can be elaborately regulated by adjusting the thermal exfoliation conditions to simultaneously disperse and anchor Fe-N4 moieties, ultimately leading to highly loaded Fe single-atom catalysts (SA-Fe-NGM) and a highly exposed morphology. The SA-Fe-NGM is found to deliver a superior oxygen reduction reaction (ORR) activity in acidic media (half-wave potential = 0.83 V vs RHE) and a high power density of 634 mW cm-2 in the H2/O2 fuel cell test. First-principles calculations further elucidate the possible catalytic mechanism for ORR based on the identified Fe-N4 active sites and the pore size distribution analysis. This work provides a novel strategy for constructing highly exposed transition metals and nitrogen co-doped carbon materials (M-N-C) catalysts for extended electrocatalytic and energy storage applications.

A facile and environmentally friendly method for preparing supercapacitor electrode carbon-based materials with ultra-long cycling stability

With the demand for next-generation energy storage equipment and industrial applications, the development of carbon-based electrode materials with more comprehensive electrochemical performance and more convenient production process has become a top priority. Here, an N/O co-doped carbon material (Z-700) was prepared by one-step carbonization with 2,6-bis(2-pyrazin-2-yl)− 4-(4-(tetrazol-5-yl)phenyl)pyridine acting as the carbon and nitrogen source. Z-700 is a clastic carbon material with non-uniform size and low specific surface area (4.1 m2/g). However, when assembled into supercapacitors, Z-700 has excellent comprehensive capacitance performance, such as a specific capacitance of 218.6F/g (0.5 A/g), a specific energy of 43.7 Wh/kg, a cycling stability of more than 100,000 cycles, and a charge/discharge rate less than 2 s (10 A/g). In addition, the assembled symmetric supercapacitor has excellent capacitance performance. This high-performance carbon-based electrode material has great application potential in industry and next-generation supercapacitors.

Peroxymonosulfate activation by concave porous S/N co-doped carbon: Singlet oxygen-dominated non-radical efficient oxidation of organics

Developing high-efficient, low-cost and environmentally friendly catalysts is essential for activating peroxymonosulfate (PMS) but remains a challenge. Recently, novel catalysts of transition metal-nitrogen co-doped carbon materials, especially Fe-N-C, have attracted much attention due to their superior performance for PMS activation. Herein, FeSO4 and ZnSO4 were added during the synthesis of ZIF-8, obtained concave N, S co-doped iron-based carbon materials (Fe-S@NC) with mesoporous structure through high-temperature pyrolysis. This porous carbon material with a depressed surface not only promoted the exposure of active sites, but also accelerated mass transfer. The synergistic effect of Fe atoms and heteroatoms significantly enhanced the activation ability of the material to PMS. Benefiting from these advantages, only 2 mg/L Fe-S1@NC and 0.5 mM PMS was required to achieve the rapid degradation of acetaminophen (ACT) (99.7%, 0.7290 min-1). Besides, the activation system has a wide pH adaptability and low leaching iron concentration. Then the reaction mechanism of Fe-S1@NC/PMS system was investigated by quenching experiments and electron paramagnetic resonance technique (EPR), it was proposed that singlet oxygen (1O2) was the primary reactive species responsible for the degradation of ACT. This study provides new insight for the design of carbon catalysts in advanced oxidation field.

KOH activated nitrogen and oxygen co-doped tubular carbon clusters as anode material for boosted potassium-ion storage capability

Carbon nanomaterials have become a promising anode material for potassium-ion batteries (KIBs) due to their abundant resources, low cost, and excellent conductivity. However, among carbon materials, the sluggish reaction kinetics and inferior cycle life severely restrict their commercial development as KIBs anodes. It is still a huge challenge to develop carbon materials with various structural advantages and ideal electrochemical properties. Therefore, it is imperative to find a carbon material with heteroatom doping and suitable nanostructure to achieve excellent electrochemical performance. Benefiting from a Na2SO4 template-assisted method and KOH activation process, the KOH activated nitrogen and oxygen co-doped tubular carbon (KNOCTC) material with a porous structure exhibits an impressive reversible capacity of 343 mAh g−1 at 50 mA g−1 and an improved cyclability of 137 mAh g−1 at 2 A g−1 after 3000 cycles with almost no capacity decay. The kinetic analysis indicates that the storage mechanism in KNOCTC is attributed to the pseudocapacitive process during cycling. Furthermore, the new synthesis route of KNOCTC provides a new opportunity to explore carbon-based potassium storage anode materials with high capacity and cycling performance.

Edge-enriched N, S co-doped hierarchical porous carbon for oxygen reduction reaction

The development of carbon materials with high electrochemical performance for next-generation energy device is emerging, especially N, S co-doped carbon materials have sparked intensive attention. However, the exploration of N, S co-doped carbon with well-defined active sites and hierarchical porous structures are still limited. In this study, we prepared a series of edge-enriched N, S co-doped carbon materials through pyrolysis of thiourea (TU) encapsulated in zeolitic imidazolate frameworks (TU@ZIF) composites, which delivered very good oxygen reduction reaction (ORR) performance in alkaline medium with onset potential of 0.94 V vs. reversible hydrogen electrode (RHE), good stability and methanol tolerance. Density functional theory (DFT) calculations suggested that carbon atoms adjacent to N and S are probable active sites for ORR intermediates in edge-enriched N, S co-doped carbon materials because higher electron density can enhance O2 adsorption, lower formation barriers of intermediates, improving the ORR performance comparing to intact N, S co-doped carbon materials. This study might provide a new pathway for improving ORR activity by the integration engineering of edge sites, and electronic structure of heteroatom doped carbon electrocatalysts.

NiS2@carbon nanocomposite with enriched N and S derived from MOF crystal as highly effective catalyst for 4-nitrophenol reduction

Herein, two-ligand nickel-based MOF (JUC-85Ni) have been prepared by choosing high N-containing and S-containing ligand. On this basis of the research, the NiS2 nanoparticles dispersed N and S co-doped carbon materials (NiS2@NSC) are fabricated through the sulfidation of JUC-85Ni precursors with thioacetamide (TAA). The rationally designed NiS2@NSC catalysts are conducted a test for catalytically reducing 4-nitrophenol (4-NP) to environment friendly 4-aminophenol (4-AP) under NaBH4 alkaline condition. The superior features endows the catalyst with outstanding catalytic activity and recycling performance, and support it great potential for wastewater treatment.

Selective Aerobic Oxidation of Csp3-H Bonds Catalyzed by Yeast-Derived Nitrogen, Phosphorus, and Oxygen Codoped Carbon Materials.

Nitrogen, phosphorus, and oxygen codoped carbon catalysts were successfully synthesized using dried yeast powder as a pyrolysis precursor. The yeast-derived heteroatom-doped carbon (yeast@C) catalysts exhibited outstanding performance in the oxidation of Csp3-H bonds to ketones and esters, giving excellent product yields (of up to 98% yield) without organic solvents at low O2 pressure (0.1 MPa). The catalytic oxidation protocol exhibited a broad range of substrates (38 examples) with good functional group tolerance, excellent regioselectivity, and synthetic utility. The yeast-derived heteroatom-doped carbon catalysts showed good reusability and stability after recycling six times without any significant loss of activity. Experimental results and DFT calculations proved the important role of N-oxide (N+-O-) on the surface of yeast@C and a reasonable carbon radical mechanism.