Formation Of Carbon Nanotubes Research Articles

Catalytic Design of Matrix-Isolated Ni-Polymer Composites for Methane Catalytic Decomposition.

Targeted synthesis of C/composite Ni-based material was carried out by the method of matrix isolation. The composite was formed with regard to the features of the reaction of catalytic decomposition of methane. The morphology and physicochemical properties of these materials have been characterized using a number of methods: elemental analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, temperature programmed reduction (TPR-H2), specific surface areas (SSA), thermogravimetric analysis, and differential scanning calorimetry (TGA/DSC). It was shown by FTIR spectroscopy that nickel ions are immobilized on the polymer molecule of polyvinyl alcohol, and during heat treatment, polycondensation sites are formed on the surface of the polymer molecule. By the method of Raman spectroscopy, it was shown that already at a temperature of 250 °C, a developed conjugation system with sp2-hybridized carbon atoms begins to form. The SSA method shows that the formation of the composite material resulted in a matrix with a developed specific surface area of 20 to 214 m2/g. The XRD method shows that nanoparticles are essentially characterized by Ni, NiO reflexes. The composite material was established by microscopy methods to be a layered structure with uniformly distributed nickel-containing particles 5-10 nm in size. The XPS method determined that metallic nickel was present on the surface of the material. A high specific activity was found in the process of catalytic decomposition of methane-from 0.9 to 1.4 gH2/gcat/h, XCH4, from 33 to 45% at a reaction temperature of 750 °C without the stage of catalyst preliminary activation. During the reaction, the formation of multi-walled carbon nanotubes occurs.

Coating of Carbon Nanotubes Using Chemical Method to Enhance the Corrosion Protection of Copper and Aluminum Metals in Seawater Medium

In this study, carbon nanotubes were prepared using a pure chemical method modified similar to the Hummers method with simple changes in the work steps. The carbon nanotubes were then coated and reduced on copper and aluminum metals using the electrodeposition method (EDP) for corrosion protection application in seawater medium (NaCl 3.5%) at four different temperatures: 20, 30, 40, and 50 °C, which were studied using three electrode potentiostats. All corrosion measurements, thermodynamics, and kinetics parameters were nominated from Tafel plots. The films deposited by the carbon nanotubes were examined by the SEM technique, and this technique showed the formation of carbon nanotubes.

Carbon nanotube production from algal biochar using microwave irradiation technology

In this study, we evaluated the transformation of algal-based biochar into carbon nanotubes by irradiation in a microwave oven at low energies (100–300 W). Three species of algae (Macrocystis pyrifera, Sarcothalia crispata, and Scenedesmus almeriensis) were selected and pyrolyzed to obtain biochar for carbon nanotubes (CNTs) growth in the presence of ferrocene as the catalyst. The CNTs obtained were characterized by dynamic light scattering, UVVIS spectroscopy, Raman spectroscopy, transmission electron microscopy, X-ray diffraction, and electrical conductivity. The results indicate that algal biochar can be used for CNT growth. The heterogeneous structure of algal biochar can initiate the graphitization process for the formation of CNTs. The characteristics of synthesized CNTs vary with the biochar source used as a precursor. Thus, both the degree of graphitization of the wall and the content of nanotubes were higher using biochar with higher carbon content (from microalga Scenedesmus almeriensis); otherwise, the hydrodynamic diameter and electrical conductivity were higher using biochar with upper mineral ash content (from microalga Macrocystis pyrifera). Furthermore, it was found that a low catalyst concentration was required to promote growth due to the reactivity of the mineral ash of the biochar, and it was demonstrated that microwave heating conditions, such as microwave power and temperature, lead to variations in the optical properties of CNTs, such as the band gap energy, CNTs content, and measurement of the size such as the hydrodynamic diameter.

Synthesis of COx-free hydrogen via natural gas decomposition over titanium dioxide-supported bimetallic catalysts

Nickel and cobalt-based titania-supported bimetallic catalysts were synthesized using the co-precipitation technique. The total metal loading varied between 20 and 60 wt% while keeping nickel to cobalt ratio of unity. In comparison with low-loading catalysts i.e., 10 and 15 wt% each of nickel and cobalt supported over titania (10NCT and 15NCT), high-loading catalysts (20NCT, 25NCT, and 30NCT) have shown higher activity and stability performances. Among the high-loading catalysts, 25NCT catalyst outperformed the rest of the catalysts with the highest methane conversion and carbon yield. The higher specific surface area (115.1 m2/g), evaluated from physisorption, facilitates better metal particle dispersion; suitable metal-support interaction, and number of reducible species determined by temperature-programmed reduction, have played a vital role in enhanced activity of 25NCT. The morphological analysis revealed the formation of carbon nanotubes via following both tip-growth and base-growth mechanisms.

The Semi-Closed Molten Salt-Assisted One-Step Synthesis of N-P-Fe Tridoped Porous Carbon Nanotubes for an Efficient Oxygen Reduction Reaction

Transition metal and heteroatom co-doped carbon nanomaterials (TM-H-C) are considered to be the most promising candidates to replace the expensive platinum-based catalysts for oxygen reduction reactions (ORR). Herein, we report a semi-closed molten salt-assisted one-step strategy for fabricating N-P-Fe-tridoped porous carbon nanotube (CNT) catalysts by using the evaporation of ZnCl2 and the catalysis of iron ions to control the heteroatoms doping process and CNT formation. The resultant densely packed porous CNT structure imparts final catalysts with an enhanced mass transfer ability for electron and ORR-involved species, ensuring a high performance in catalyzing the ORR. Significantly, the optimal catalysts show a half-wave potential of 0.89 V (vs. RHE), which is better than commercial platinum-based catalysts and most reported TM-H-C ORR catalysts. Impressively, when applied to a primary inc-oxygen (Zn–O2) battery, the synthesized catalyst comprehensively outperforms the state-of-the-art platinum-based catalyst in both its maximum power density and specific capacity.

Effect of Fe on the pyrolysis products of lignin, cellulose and hemicellulose, and the formation of carbon nanotubes

In response to severe climate change on a global scale, a shift from fossil fuels to renewable energy is proposed, leading to the high utilization of biomass resources. The current study examined the characteristics of the pyrolysis products of lignin, cellulose and hemicellulose using different Fe contents, and carbon nanotubes (CNTs) were successfully prepared under conventional pyrolysis conditions. The results showed that the addition of 10% Fe significantly increased the content of H2, CH4, and CO in the pyrolysis gas and inhibited the release of CO2. The addition of 10% Fe inhibited the decomposition of lignin surface functional groups and promoted the decomposition of hemicellulose surface functional groups. At the same time, diffraction peaks due to carbon deposition can be observed on the surface of Fe powder. Lignin biochar contained a large number of pores, and the number of pores increased with an increase in the added Fe. The existence of CNTs was observed in the Fe of cellulose corresponding to a small quartz boat, and a mechanism for the preparation of CNTs by chemical vapor deposition using cellulose as raw material was proposed.

Synthesis of Carbon Nanotubes Using Modified Hummers Method for Cathode Electrodes in Dye-Sensitized Solar Cell

In this research, carbon nanotubes (CNTs) is prepared through the Hummers method with a slight change in some of the work steps, thus, a new method has been created for preparing carbon nanotubes which is similar to the original Hummers method that is used to prepare graphene oxide. Then, the suspension carbon nanotubes is transferred to a simple electrode position platform consisting of two electrodes and the cell body for the coating and reduction of the carbon nanotubes on ITO glass which represents the cathode electrode while platinum represents the anode electrode. The deposited layer of carbon nanotubes is examined through the scanning electron microscope technique (SEM), and the images throughout the research show the formation of carbon nanotubes. In the second part of the research, a dye-sensitized solar cell (DSSC) is prepared to utilize carbon nanotube as the cathode electrode, titanium oxide nanoparticles as the anode electrode by using a natural dye (pomegranate dye). The assembled dye-sensitized solar cell (DSSC) is tested by two electrodes potentiostat using Xenon light source and all parameters are established; Vocp, Imax, Vmax, Isc and calculated full factor and conversion efficiency.

Compatibilized polylactide/polyamide 11 blends containing multiwall carbon nanotubes: Morphology, rheology, electrical and mechanical properties

The effect of adding multiwall carbon nanotubes (CNTs) on the morphology and properties of reactively compatibilized polylactide/polyamide 11 (PLA/PA11) blends with a 75/25 wt% composition was evaluated. The PLA/PA11 blends were compatibilized using an epoxy-based chain extender. The blends and nanocomposites were prepared using an internal mixer. The effects of the chain extender concentration, mixing strategy, PLA molecular weight and CNT concentration on the morphology were evaluated in light of rheological, electrical and mechanical characterization. Upon pre-mixing CNTs with PLA the morphology of the dispersed phase evolved to connected non-spherical, non-coalescing PA11 domains bridged by CNTs at the interface. A network-like structure was formed in the nanocomposites containing 2–3 wt% of nanoparticles characterized by a transition from liquid-to solid-like behavior. The electrical conductivity remained in the insulating range, largely due to inadequate interconnectivity of PA11-CNT domains. The nanocomposites based on the lower molecular weight PLA displayed larger relative increase of the electrical conductivity and Young modulus, compared to the neat blend, indicative of a better CNT dispersion and formation of a more interconnected PA11-CNT network.

Microemulsion nanoreactor applied for the synthesis of iron-based catalysts for carbon nanotube formation

Catalysts play an important role in the production of carbon nanotubes, and the preparation of catalysts has always been a hot topic. In this study, microemulsion nanoreactor was constructed and applied for the first time to prepare carbon nanotube catalysts. The natural “pool” formed with the oil phase as an external substance and the surfactant as the boundary provides a reactor stable at the nanometer level for the co-precipitation reaction of Fe (NO3)3•9H2O and Al (NO3)3•9H2O, and the precipitation reaction is more uniform and sufficient. The active ingredient of the catalyst has better dispersion. Carbon nanotubes are nucleated with the active ingredient as the site and have a smaller and uniform diameter. Moreover, we want to control the size of the reactor by changing the surfactant concentration. The best performance was obtained when the surfactant content is 14 %, with the hydration diameter of microemulsion prepared of about 50 nm, the particle size and specific surface area of catalyst of about 60 nm and 255.97 m2/g. The diameter of carbon nanotubes grown under the catalyst was mainly distributed between 6 and 13 nm, with low defect degree. The results show that the reverse microemulsion method has unique advantages in the preparation of nano-scale materials, and this study provides a reference for the preparation of carbon nanotubes catalysts using microemulsion nanoreactor.

Optimizing barium promoter for nickel catalyst supported on yttria‐stabilized zirconia in dry reforming of methane

AbstractBarium doping effect on the activity and stability of nickel‐based catalysts, supported on yttria‐stabilized zirconia (Ni‐YZr), was investigated in dry reforming of methane. Catalysts were characterized by several techniques (nitrogen sorption, X‐ray diffraction [XRD], scanning electron microscopy with energy dispersive X‐ray, transmission electron microscopy [TEM], thermogravimetric analysis [TGA], temperature programmed oxidation, CO2‐TPD, H2‐TPR) and were tested in a fixed‐bed reactor at 800°C and 42,000 mL/h gcat. Barium played a crucial role in enhancing catalyst reducibility and CO2 adsorption at high temperatures, as indicated by the activity and stability of the Ni‐YZr catalyst. The addition of 4.0 wt% of barium appeared to be the optimal loading, allowing for CH4 conversion of 82%, which remained constant for 7 h of reaction, compared with 72% of barium‐unpromoted Ni‐YZr at 800°C. TEM images of the spent catalysts revealed the formation of multiwalled carbon nanotubes on all samples. The TGA analysis showed, however, that an increase in baria loading significantly reduced the coke formation amount, indicating the inhibition of coke formation and the enhancement of the catalytic activity. Such improvement in activity and stability was attributed to the incorporation of barium into YZr support, as revealed by XRD analysis, which inhibited the sintering of the catalysts support.

Carbon nanotubes production from catalytic pyrolysis of polyethylene over nickel-based catalysts: The influence of support materials

To understand the influence of support materials on the reactivity of catalysts, four nickel- based catalysts supported on different materials (ZrO2, TiO2, Nb2O5, and Al2O3) were developed and investigated in the carbon nanotubes production from catalytic pyrolysis of polyethylene using two-stage fixed bed reactor. The results showed that the Ni/Al2O3 catalyst generated the highest carbon material yield of 36.5 wt%, while the order of carbon material yield was Ni/Al2O3 > Ni/TiO2 > Ni/ZrO2 > Ni/Nb2O5. To explore the correlation between catalysts properties and carbon products, the essential structural characteristics of fresh catalyst and reacted catalyst were analyzed by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (TEM), temperature program oxidation (TPO), nitrogen adsorption measurements and Raman spectroscopy. The Ni/Al2O3 catalyst with the highest surface area, abundant pore structure, and moderate metal-support interaction promoted the decomposition of pyrolysis volatiles to produce carbon nanomaterials, which were consist of carbon nanotubes (CNTs). CNTs are the main component of carbon materials produced, accounting for a relatively high proportion. In comparison, the large metal active particles and weak metal-support interaction of Ni/TiO2 catalyst had a negative impact on the formation of CNTs, generating many fishbone like carbon nanofibers (CNFs). Moreover, the poor pore structure and larger metal active particles for Ni/ZrO2 and Ni/Nb2O5 catalyst led to a low carbon deposition yield and poor quality of CNTs. The results provide valuable data and theoretical support for the research on the preparation of valuable carbon nanotubes from waste plastics.

Direct formation of carbon nanotube wiring with controlled electrical resistance on plastic films

We have developed a simple method to fabricate multi-walled carbon nanotube (MWNT) wiring on a plastic film at room temperature under atmosphere pressure. By irradiating a MWNT thin film coated on a polypropylene (PP) film with a laser, a conductive wiring made of a composite of MWNT and PP can be directly fabricated on the PP film. The resistance of MWNT wiring fabricated using this method were ranging from 0.789 to 114 kΩ/cm. By changing the scanning speed of laser, we could fabricate various regions with different resistances per unit length even within a single wiring. The formation mechanism of the MWNT wiring with tunable resistance was discussed from both experimental results, such as microscopic structural observation using cross-sectional scanning electron microscopy and microscopic Raman imaging, and simulation results, such as heat conduction in the film during local laser heating. The results suggest that the MWNT wiring was formed by PP diffusion in MWNT at high temperature. We also demonstrated that excess MWNTs that were not used for wiring could be recovered and used to fabricate new wirings. This method could be utilized to realize all-carbon devices such as light-weight flexible sensors, energy conversion devices, and energy storage devices.

Co2P Nanoparticles Encapsulated in N-Doped Carbon Nanotubes as a Bifunctional Oxygen Catalyst for a High-Performance Rechargeable Zn–Air Battery

A significant but challenging task is the development of a rechargeable Zn–air battery bifunctional catalyst. Here, a supramolecular self-assembly of poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P123) was designed to construct Co2P nanoparticles encapsulated in N-doped carbon nanotubes (Co2P@NCNT-x). The results show that P123 is an important factor in the formation of N-doped carbon nanotubes coated with Co2P nanoparticles. The Co2P@NCNT-4 catalyst exhibits the maximum limiting diffusion current density (5.2 mA·cm–2 under 808.9 hPa) and a more positive onset potential (0.90 V vs RHE) and half-wave potential (0.84 V vs RHE) due to the greater specific surface area and higher graphitization degree. Its potential gap is only 0.87 V versus RHE which is between the half-wave potential of the oxygen reduction reaction and the Ej = 10 of the oxygen evolution reaction. The Co2P@NCNT-4-based rechargeable Zn–air battery shows the highest peak power density (217 mW·cm–2), the highest specific capacity (831.25 mA h·gZn–1 at 10 mA·cm–2), and remarkable cycle stability. This preparation method can provide ideas for designing other transition metal phosphide catalysts in the future.

Comparative studies on promotional effect of Pr6O11, Nd2O3 and Sm2O3 on Ni–SiO2 for pressurized carbon dioxide reforming of methane

The 7 wt% rare earth metal oxide promoted Ni–SiO2 catalysts of Ni–7Pr6O11–SiO2, Ni–7Nd2O3–SiO2, and Ni–7Sm2O3–SiO2 were prepared by the complex-decomposition method, and were comparatively evaluated for pressurized carbon dioxide reforming of methane (CRM) under severe conditions of 750 °C, 1.0 MPa, CH4/CO2 = 1, and gas hourly space velocity of 53200 mL/(g·h). The addition of rare earth metal oxide does not affect the Ni dispersion, and all of the catalysts show similarly high Ni dispersion of 16.0% ± 0.2%. As a result, all of the catalysts are highly active for pressurized CRM, the initial CH4 conversions of which approach the thermodynamic equilibrium (47.0% ± 0.2%). In contrast, a clearly favorable effect of the added rare earth metal oxide on the stability of Ni–SiO2 was revealed from the CRM results for a time-on-stream of 50 h, and the highest stability without an observable decrease in the conversions of CH4 and CO2 was obtained over Ni–7Sm2O3–SiO2. Based on the characterization results of thermogravimetric differential scanning calorimetry (TG-DSC) and transmission electron microscopy (TEM), the improved stability of Ni–7Pr6O11–SiO2, Ni–7Nd2O3–SiO2, and Ni–7Sm2O3–SiO2 for pressurized CRM was manifested mainly as the suppressed formation of carbon nanotubes over the catalyst surface, the extent of which is dependent on the specific rare earth metal oxide. Moreover, the consecutive temperature programmed surface reaction of CH4, CO2, and O2 over Ni–7Sm2O3–SiO2 vigorously reveals that the addition of Sm2O3 into Ni–SiO2 inhibits the CH4 decomposition but enhances the oxidization of the carbon species by CO2, leading to the well-balanced rates for forming and removing the coke over Ni–7Sm2O3–SiO2. These findings are not only beneficial to deeply understanding the promotional effect of rare earth metal oxides on Ni-based catalysts for CRM, but also important for extending the application of the less studied rare earth metal oxides as promoters for the metal-supported catalysts.

Synthesis and structural features of black TiO2 nanotubes after annealing in hydrogen

TiO2 nanotubes (TiO2 NTs) with a diameter of 60 nm, a wall thickness of 12 nm, and a length of 13 μm were synthesized by anodic oxidation of Ti plates in ethylene glycol with the addition of NH4F and H2O. The intense black color of TiO2 NTs is acquired after heating in hydrogen at 500 °C. The carbon content on the surface of the black TiO2 TNs is 20.1 ± 1 at.%, of which 13.8 at.% is graphite carbon. It was found that only 2.4 at.% of the titanium ions exist as Ti3+ ions. It has been concluded that carbon contributes to the black color of TiO2 NTs. The ordering in the arrangement of carbon networks of amorphous carbon in the black TiO2 NTs is revealed. There is an oriented arrangement of carbon rings along the walls of the black TiO2 NTs, which is similar to the formation of carbon nanotubes inside the pores of TiO2 NTs. The formation of graphitized carbon in a regular TiO2 nanoporous structure makes it possible to obtain intensely colored films.

Carbon nanotube-decorated hierarchical porous nickel/carbon hybrid derived from nickel-based metal-organic framework for enhanced methyl blue adsorption

This work reports the incorporation of coordinated water into Ni-BTC nanorods (Ni-BTC-O) which induces their structural transformation to Ni-BTC nanofibres (Ni-BTC-F). The carbonization of the Ni-BTC nanofibres at 600 °C results in the formation of carbon nanotube (CNT)-decorated hierarchical porous nickel/carbon hybrid (labelled as Ni/C-600) with enlarged pores. In contrast, the Ni/C hybrid obtained from the carbonization of the original (unmodified) Ni-BTC nanorods (Ni-BTC-O) at 600 °C (labelled as Ni-BTC-O-600) exhibits smaller pore size and does not show the formation of CNTs. The Ni/C-600 hybrid derived from Ni-BTC-F shows a very high adsorption capacity of 686.8 mg g−1 toward methyl blue (MB) dye. This is approximately 4.8 times higher than the adsorption capacity of Ni-BTC-O-600 (144.1 mg g−1). The higher adsorption performance of Ni/C-600 relative to Ni-BTC-O-600 can be attributed to its larger pore volume, hierarchical porosity, and additional adsorption sites provided by the CNTs. In addition, the Ni/C-600 hybrid can maintain 90% of its adsorption capacity after 5 consecutive cycles, demonstrating its potential as an efficient and recyclable adsorbent for MB dye.

Влияние шероховатости барьерного слоя на формирования наночастиц катализатора роста углеродных нанотрубок

This article compares TiN layers produced by electron beam evaporation (EBE) and atomic layer deposition (ALD) for the effect of barrier layer deposition technology on the formation of carbon nanotube (CNT) growth catalyst nanoparticles. The layers obtained by EBE have a roughness 1.5 times higher than the layers deposited by the ALD method (Ra = 1 nm and Ra = 0.6 nm). Nanoparticles formed on the surface of the EBE layer are characterized by a large average size (about 30 nm) and a 1.3 times greater dispersion of the distribution compared to nanoparticles formed on the ALD layer. TiN layers obtained by EBE are characterized by better surface wettability in comparison with ALD layers. The contact angle for catalyst nanoparticles on the surface of the EBE layer of TiN is about 30 degrees and approaches 90 degrees for ALD layers. Catalyst spreading is due to the Wenzel model. It is shown that the higher surface roughness of the EBE samples is associated with the crystallization of TiN, since the layer formation process proceeds at a higher temperature compared to the ALD process. For this reason, the use of barrier layers obtained by the ALD method is preferable for the formation of CNT growth catalyst nanoparticles on their surface.

Effect of Barrier Layer Roughness on the Formation of Nanoparticles of the Carbon Nanotube Growth Catalyst

This article compares TiN layers produced by electron beam evaporation (EBE) and atomic layer deposition (ALD) for the effect of barrier layer deposition technology on the formation of carbon nanotube (CNT) growth catalyst nanoparticles. The layers obtained by EBE have a roughness 1.5 times higher than the layers deposited by the ALD method (R a =1 nm and R a =0.6 nm). Nanoparticles formed on the surface of the EBE layer are characterized by a large average size (about 30 nm) and a 1.3 times greater dispersion of the distribution compared to nanoparticles formed on the ALD layer. TiN layers obtained by EBE are characterized by better surface wettability in comparison with ALD layers. The contact angle for catalyst nanoparticles on the surface of the EBE layer of TiN is about 30 degrees and approaches 90 degrees for ALD layers. Catalyst spreading is due to the Wenzel model. It is shown that the higher surface roughness of the EBE samples is associated with the crystallization of TiN, since the layer formation process proceeds at a higher temperature compared to the ALD process. For this reason, the use of barrier layers obtained by the ALD method is preferable for the formation of CNT growth catalyst nanoparticles on their surface. Keywords: electron beam evaporation, atomic layer deposition, roughness, wetting, catalyst nanoparticles.

Insights into the formation of multiwall carbon nanotubes using simple flame pyrolysis method

Herein, we discuss the formation of multiwall carbon nanotubes (MWCNTs) during the simple and effective flame pyrolysis of ferrocene solution in ethanol with the help of alcohol lamp. The method is unique and simple one to prepare impure MWCNTs in the best possible way. Systematic investigations showed that the in-situ generated maghemite plays an important role in the formation and development of the MWCNTs. The growth of the maghemite impregnated MWCNTs were thoroughly studied using sophisticated instruments viz. XRD, BET, HR-SEM, and TEM analysis in details and on the basis of these, the growth mechanism is discussed.

Autocatalytic formed bamboo-like N-doped carbon nanotubes encapsulated with Co nanoparticles as highly efficient catalyst for activation of peroxymonosulfate toward degradation of tetracycline

Co-based catalysts activated peroxymonosulfate (PMS) for organic pollutants degradation has been extensively studied. Co dissolution of Co-based catalysts would result in secondary environmental contamination. Co autocatalysis the formation of bamboo-like N-doped carbon nanotubes to confine Co nanoparticles (Co NPs). Herein, the N-doped carbon nanotubes encapsulated Co (Co@NCTs) were successfully synthesized through a one-step high-temperature calcination method at different temperatures. Co@NCTs-800 exhibited excellent catalytic performance, the degradation efficiency of tetracycline (TC) could reach 94.5% with only 0.05 g/L catalyst in activating PMS. In addition, the encapsulation of carbon nanotubes inhibits the dissolution of Co, the Co2+ dissolution was 0.0594 mg/L in 40 min in the system of Co@NCTs-800/PMS. Free radical quenching tests, electron paramagnetic resonance, and electrochemical measurements revealed that the non-radical route was dominated by tetracycline degradation, with singlet oxygen (1O2) and electron transfer as the principal active species. The N-doped carbon nanotubes can effectively encapsulate Co, which not only reduces the leaching of Co but also play a synergistic role with Co in degrading organic pollutants. In addition to this, the degradation mechanism and pathways of TC were further investigated. The Co@NCTs-800/PMS system was also able to successfully decompose a variety of organic contaminants, demonstrating that it has real application potential in wastewater.