Carbon Monoxide Generation Research Articles

Biological treatment of biowaste as an innovative source of CO-The role of composting process.

Carbon monoxide (CO) is an essential "building block" for producing everyday chemicals on industrial scale. Carbon monoxide can also be generated though a lesser-known and sometimes forgotten biorenewable pathways that could be explored to advance biobased production from large and more sustainable sources such as bio-waste treatment. Organic matter decomposition can generate carbon monoxide both under aerobic and anaerobic conditions. While anaerobic carbon monoxide generation is relatively well understood, the aerobic is not. Yet many industrial-scale bioprocesses involve both conditions. This review summarizes the necessary basic biochemistry knowledge needed for realization of initial steps towards biobased carbon monoxide production. We analyzed for the first time, the complex information about carbon monoxide production during aerobic, anaerobic bio-waste treatment and storage, carbon monoxide-metabolizing microorganisms, pathways, and enzymes with bibliometric analysis of trends. The future directions recognizing limitations of combined composting and carbon monoxide production have been discussed in greater detail.

Renal Clearable Catalytic 2D Au-Porphyrin Coordination Polymer Augmented Photothermal-Gas Synergistic Cancer Therapy.

As a gasotransmitter, carbon monoxide (CO) possesses antitumor activity by reversing the Warburg effect at higher concentrations. The targeted delivery of carbon monoxide-releasing molecules (CORMs) using nanomaterials is an appealing option for CO administration, but how to maintain CO above the threshold concentration in tumor tissue remains a challenge. Herein, a nanozyme-catalyzed cascade reaction is proposed to promote CO release for high-efficacy photothermal therapy (PTT)-combined CO therapy of cancer. A gold-based porphyrinic coordination polymer nanosheet (Au0 -Por) is synthesized to serve as a carrier for CORM. It also possesses excellent glucose oxygenase-like activity owing to ultrasmall zero-valent gold atoms on the nanosheet. The catalytically generated H2 O2 can efficiently catalyze CORM decomposition, which enables in situ generation of sufficient CO for gas therapy. In vivo, the Au0 -Por nanosheets-enhanced photoacoustic imaging (PAI) and fluorescence imaging collectively demonstrate high tumor-targeting efficiency and nanomaterial retention. Proven to have augmented therapeutic efficacy, the nanoplatform can also be easily degraded and excreted through the kidney, indicating good biocompatibility. Thus, the application of rational designed Au0 -Por nanosheet with facile approach and biodegradable property to PAI-guided synergistic gas therapy can provide a strategy for the development of biocompatible and highly effective gaseous nanomedicine.

A photocatalytic carbon monoxide-generating effervescent microneedle patch for improved transdermal chemotherapy.

Carbon monoxide (CO) is regarded as a promising therapeutic agent for chemotherapy sensitization. To simultaneously achieve controllable in situ CO production and efficient chemotherapeutics delivery is of great significance. Here, we presented a polyvinylpyrrolidone (PVP) core-shell microneedle (MN) system that encapsulated the effervescent component, photocatalyst, and doxorubicin hydrochloride (Dox·HCl) for CO-sensitized chemotherapy. Upon the insertion of MNs, the effervescent component, composed of sodium bicarbonate and tartaric acid, was exposed to interstitial fluid, leading to the burst release of carbon dioxide (CO2). The generated gas not only enhanced the diffusion of Dox·HCl but also served as a substrate for the photocatalytic generation of CO. From the experimental results, the photocatalyst CuS atomic layers (CAL) displayed an effective CO2 photoreduction performance, which could realize an irradiation time/intensity-dependent CO-controlled release. Ex vivo permeation studies demonstrated that effervescent CO2 production markedly enhanced the intradermal diffusion of Dox·HCl. Eventually, the robust antitumor efficacy of this versatile MN platform was proved in B16F10-bearing nude mice. This CO-sensitized chemotherapeutic MN system offered a novel strategy for transdermal gas/drug delivery, which might provide a new direction in tumor suppression.

Microwave Assisted Solvent Free Catalytic Amino-Carbonylation of Aryl Bromide by Using μ-Dichloro-bis(benzylidene aniline)palladium(II) Complex as Catalyst

Solvent-free aminocarbonylation (Heck carbonylation) of aryl halide, catalyzed by μ-dichloro-bis(benzylidene aniline)palladium(II) complex yields dimethyl benzamide and their substitutes, has several useful industrial applications. In present work, dimethylformamide (DMF) serves as an effective in situ supplier of dimethyl amine and carbon monoxide. Bromobenzene along with more electron-rich aryl bromide generally undergo these reactions very smoothly, but the yield of respective products is less. To increase the yields of aryl amide, it is needed to be add amines from the external sources to the reaction mixture. Imidazole and aniline were used as good reaction partners, or amines, in this experiment. For obtaining the best results, several reactions were conducted in the presence of base i.e. potassium tert-butoxide. Potassium tert-butoxide was responsible for the better decomposition of DMF and imidazole as an additive. The carbonylation reactions described here depend on the efficiency of in situ generation of carbon monoxide, which can be a suitable unconventional route to traditional carbonylation procedures for small-scale operation when a quick reaction time is sought where direct use of CO gas is not possible.

A Pd-Sn heterobimetallic catalyst for carbonylative Suzuki, Sonogashira and aminocarbonylation reactions using chloroform as a CO surrogate.

Herein, we report a heterobimetallic Pd-Sn catalyst for the carbonylative Suzuki coupling, aminocarbonylation reaction, and carbonylative Sonogashira coupling of aryl halides with boronic acids, amines, and aromatic alkynes leading to a three-component coupling reaction using in situ generated carbon monoxide. Under the optimized reaction conditions, a variety of bisaryl ketones, amides, and aromatic ynones have been synthesized in moderate to good yields in a one-pot fashion. The reported catalyst has wide reaction scope with good functional group tolerance.

Selection justification of the wood pulp and crown combustion parameters for the calculation of the crown forest fires impact on Vietnamese energy facilities

The selection of specific carbon monoxide generation rate and specific mass gasification rate values is necessary for mathematical modeling of crown forest fires and their thermal effects on Vietnamese energy facilities. The study presents results from experiments on burning trunk wood pulp and crown samples of the most common deciduous and coniferous trees in Vietnam. Specific carbon monoxide generation rate and specific mass gasification rate were measured for wood and crown samples under flame combustion mode. The experimental results were compared with literature values, and it was found that the time-average experimental values of specific mass gasification rate fell within the range specified in the fire load database by Koshmarov 2000 for both coniferous and deciduous trees.

Electrocatalytic CO 2 Reduction over Bimetallic Bi-Based Catalysts: A Review

Electrocatalytic CO ₂ Reduction over Bimetallic Bi-Based Catalysts: A Review

An electro-hydrogen cogeneration system combining compressed air energy storage and methanol cracking reaction

In order to solve the problems of insufficient utilization of compression heat in compressed air energy storage (CAES) system and the need for supplementary heat in methanol cracking reaction (MCR) for hydrogen production, an electro-hydrogen cogeneration system combining CAES and MCR was proposed in this study. The energy storage module of this system consists of two parts: adiabatic compression and near-isothermal compression. The heat generated by adiabatic compression is used to preheat methanol, and carbon monoxide generated by methanol cracking is used to supplement the heat of the cracker and the energy release module of the CAES system, respectively. The proposed system makes full use of low-grade compression heat while consuming the generated carbon monoxide to output hydrogen to the outside. By constructing a systematic thermodynamic model of the system, the effects of the key parameters on the system performance were investigated in depth. The results show that the energy efficiency and exergy efficiency of the system can reach 85.71 % and 80.94 %, respectively. When the suction pressure of the water-air coexisting tank is increased from 5 atm to 20 atm, the air storage mass increases by 33.96 %. At the cracking temperature of 708 K, the energy storage density can reach 12.37 kWh/m3, the hydrogen production mass is 3113.38 kg, and the relative energy saving rate is 54.38 %. The system performance can be improved by increasing the turbine inlet temperature of the first section and decreasing the turbine pressure ratio of the first section while keeping the total pressure ratio constant. The combustion chamber, cracking reactor and heat exchanger are the main factors that cause the exergy loss, accounting for 46.54 %, 30.16 % and 6.67 % of the total, respectively.

Kinetic, products distribution, and mechanism analysis for the pyrolysis of polyglycolic acid toward carbon cycle

Present investigation was aimed at exploring the pyrolysis kinetics, product distribution, and mechanisms of polyglycolic acid (PGA) via experiments and reactive force field molecular dynamic (ReaxFF-MD) simulations to establish a foundation for the recycling of raw materials in the future. The kinetic analysis presented that the PGA pyrolysis belonged to the contracting cylinder model with the apparent activation energy ranged from 138.1 to 141.7 kJ/mol. The gaseous product was determined to contain carbon dioxide, carbon monoxide, and formaldehyde through TG-IR and TG-MS, and Py-GC/MS results showed that the yield of glycolide reached the maximum at 450 °C. The ReaxFF-MD simulation revealed that the initial pyrolysis pathway for PGA was the cleavage of alkoxy bond, followed by CC bond and acyloxy bond with the generation of carbon dioxide, carbon monoxide, formaldehyde, and ethenone. This study would provide comprehensive experiment data and meaningful guidance for recycling PGA to achieve a closed-loop economy.

Glucose oxidase-amplified CO generation for synergistic anticancer therapy via manganese carbonyl-caged MOFs

Carbon monoxide (CO) as one of the therapeutic gaseous molecules has been widely applied for treating various diseases, especially in cancer therapy. However, the in situ-triggered and efficient transport of CO to tumors are the primary obstacles that limit its clinical applicability. To address this obstacle, herein, a H2O2-triggered CO gas releasing nanoplatform has been designed by embedding manganese carbonyl (MnCO) into Zr (IV)-based metal-organic frameworks (MOFs). The porous structures of MOFs provide encapsulation capacity for glucose oxidase (GOx) loading, thereby catalyzing the endogenous glucose into gluconic acid and H2O2 to accelerate CO release and energy depletion. In the meantime, the Mn2+ produced by MnCO can react with intracellular H2O2 via the Fenton reaction to form cytotoxic •OH. Therefore, the synthesized gas nanogenerator demonstrated a synergistic efficacy of CO gas therapy, reactive oxygen species (ROS)-mediated therapy, and energy starvation to prevent tumor growth. Both in vitro and in vivo studies indicated that this multifunctional nanoplatform not only successfully inhibited tumors through a synergistic effect, but also provided a new technique for the creation of starvation/gas/chemodynamic combination therapy in a single material. Statement of significanceIn this study, we developed a H2O2 responsive CO gas nanogenerator to augment the in-situ generation of CO gas for combined modality therapy of tumors. The nanogenerator was constructed by encapsulating glucose oxidase (GOx) and manganese carbonyl (MnCO) into UiO-67-bpy, which can catalyze the conversion of intracellular glucose to H2O2 for cutting off energy supply of cancer cells. Meanwhile, the cumulated H2O2 can trigger the release of CO for gas therapy and generation of •OH for chemodynamic therapy (CDT) via the Fenton-like reaction, thereby resulting in apoptosis of the cancer cells. Collectively, our designed nanotherapeutic agent not only displays the synergistic therapy efficacy of starvation-enhanced CO gas therapy and CDT, but also provides an efficient strategy for developing the intelligent nanocarrier for CO gas delivery and release.

Effect of Coal Dust Content on the Low-temperature Oxidation of Silo Coal.

Coal’s low-temperature oxidation (LTO) poses a significant threat to the safety of storing coal in silos. This study investigates the impact of coal dust content on the LTO characteristics of silo coal samples. The results indicate that the larger the coal dust content the higher the oxygen (O2) consumption rate and carbon monoxide (CO) generation rate and the stronger the LTO capacity. To clear the mechanism of the impact, the thermal physical characteristics were studied and thermogravimetric and differential thermal analysis (TG-DTA) experiments were performed on various coal samples. The results show that, first, with the increase of coal dust content, the thermal conductivity of the silo coal samples initially increased and then decreased, whereas the thermal diffusion and heat capacity decreased and increased linearly, respectively. This indicates that the heat storage capacity of the silo coal sample is enhanced with the increase of the coal dust content. Second, the maximum oxygen absorption rate and differential thermal reduction value of the coal samples increased linearly with the decrease in their particle size; this result verifies that decreasing the particle size of silo coal can advance its LTO process. The study findings indicate that the risk of LTO and spontaneous combustion of silo coal can be effectively reduced by controlling the coal dust content (fine coal particles).

Rhodium(I)-Catalyzed [2+2+1]-Carbonylative Cycloaddition of Diynes with Anthracene α-Diketone as the Source of CO

AbstractWe report on the use of anthracene α-diketone as a source of carbon monoxide (CO) in carbonylation reactions. Photoirradiation by a 5 W blue LED of a diyne in the presence of anthracene α-diketone and a rhodium(I) catalyst resulted in a [2+2+1]-carbonylative cycloaddition of the diyne to CO released from the anthracene α-diketone to give a high yield (up to 99%) of the corresponding cyclopentadienone. This is the first demonstration of a CO-gas-free carbonylation reaction using anthracene α-diketone. Light irradiation was a major factor both in the generation of CO from anthracene α-diketone and in the catalytic activity. A halogen lamp, a fluorescent lamp, or sunlight also served as a light source for this reaction. With this system, there is no need for an additional reagent for generating CO.

Palladium-Catalyzed Aminocarbonylation of Isoquinolines Utilizing Chloroform-COware Chemistry.

The carbonyl group forms an integral part of several drug molecules and materials; hence, synthesis of carbonylated compounds remains an intriguing area of research for synthetic and medicinal chemists. Handling toxic CO gas has several limitations; thus, using safe and effective techniques for in or ex situ generation of carbon monoxide from nontoxic and cheap precursors is highly desirable. Among several precursors that have been explored for the generation of CO gas, chloroform can prove to be a promising CO surrogate due to its cost-effectiveness and ready availability. However, the one-pot chloroform-based carbonylation reaction requires strong basic conditions for hydrolysis of chloroform that may affect functional group tolerability of substrates and scale-up reactions. These limitations can be overcome by a two-chamber reactor (COware) that can be utilized for ex situ CO generation through hydrolysis of chloroform in one chamber and facilitating safe carbonylation reactions in another chamber under mild conditions. The versatility of this "Chloroform-COware" technique is explored through palladium-catalyzed aminocarbonylation of medicinally relevant heterocyclic cores, viz., isoquinoline and quinoline.

Heme Oxygenase-1 as Therapeutic Target for Diabetic Foot Ulcers.

A diabetic foot ulcer (DFU) is one of the major complications of diabetes. Wound healing under diabetic conditions is often impaired. This is in part due to the excessive oxidative stress, prolonged inflammation, immune cell dysfunction, delayed re-epithelialization, and decreased angiogenesis present at the wound site. As a result of these multifactorial impaired healing pathways, it has been difficult to develop effective therapeutic strategies for DFU. Heme oxygenase-1 (HO-1) is the rate-limiting enzyme in heme degradation generating carbon monoxide (CO), biliverdin (BV) which is converted into bilirubin (BR), and iron. HO-1 is a potent antioxidant. It can act as an anti-inflammatory, proliferative, angiogenic and cytoprotective enzyme. Due to its biological functions, HO-1 plays a very important role in wound healing, in part mediated through the biologically active end products generated by its enzymatic activity, particularly CO, BV, and BR. Therapeutic strategies involving the activation of HO-1, or the topical application of its biologically active end products are important in diabetic wound healing. Therefore, HO-1 is an attractive therapeutic target for DFU treatment. This review will provide an overview and discussion of the importance of HO-1 as a therapeutic target for diabetic wound healing.

Me-N-C Electrocatalysts for Electrochemical CO2 Reduction to High-Value Products

The development of sustainable carbon-neutral energy technologies to mitigate greenhouse gas emissions has become imperative and urgent. Of special interest and importance in this context is the use of electricity from intermittent renewable energy sources (wind, solar) for electrochemical conversion of carbon dioxide (CO2) to easily storable and transportable value-added products: fuels and feedstock chemicals. Nanoparticles of non-precious metals, e.g., Cu, Sn, Co, show high activity for electrochemical CO2 reduction reaction (CO2RR) but suffer from poor selectivity, resulting in a mixture of products that require tedious and costly separation. Recently, transition metal- and nitrogen-doped carbon (Me-N-C) materials have been emerged as promising CO2RR catalysts thanks to their well-defined structures and good activity. However, their selectivity, while respectable for the generation of carbon monoxide (CO), is low for high energy-content products. A limited understanding of reaction pathways and degradation mechanism of Me-N-C catalysts for CO2RR has additionally stemmed a rational design of these materials.In this presentation, we summarize our study of the activity, selectivity, and stability of Me-N-C (Me = Fe, Co, Ni, or Cu, etc.) catalysts for the CO2RR, focusing on the role of the local coordination environment at metal centers and metal-carbon substrate interactions. We also report the obtained bimetallic M1M2-N-C catalysts, designed to enable the formation of multi-carbon products through CO2RR and utilizing high surface-area three-dimensional carbon matrix as support for metal sites with improved CO2RR activity. The main objective of this work is to use Me-N-C catalysts to produce high energy-density chemicals, enhance mechanistic understanding, and bring CO2RR closer to practical applications.

Conditional over-expression of heme-oxygenase 1 in myelomonocytic cells reduces hypertension and vascular inflammation

Abstract Background Arterial hypertension is one of the most important modifiable risk factors for all-cause morbidity and mortality worldwide. Angiotensin II (Ang II) plays a pathogenic role in the development of hypertension, vascular dysfunction, inflammation and tissue damage. In the context of hypertension, heme-oxygenase 1 (HO-1) gene expression is upregulated as an antioxidant defense system in response to AngII through its action on heme catabolism, which generates carbon monoxide (CO), ferritin and biliverdin, which is reduced to bilirubin by biliverdin reductase A (BLVRA). Previous studies have shown the important role of HO-1 in the maturation and migration of immune cells. Myeloid HO-1 modulates macrophage polarization and protects against ischemia-reperfusion damage. However, the role of myeloid cell specific HO-1 in the detrimental effects of AngII induced vascular dysfunction has not yet been explored. Objectives To investigate the potential vascular protection of myeloid cell specific overexpression of HO-1 in AngII-induced arterial hypertension. Methods Hypertension was induced in 8–13 weeks old male mice with selective over-expression of HO-1 (HO-1indLysMcre) in myelomonocytic cells versus LysMCre/wt by AngII infusion (1mg/kg/d). Blood pressure was recorded by tail-cuff. Bilirubin levels were quantified in plasma by High Performance Liquid Chromatography (HPLC). The quantification of adherent and rolling leukocytes in carotid arteries was detected by intravital video microscopy (IVM). Endogenuos Thrombin potential (ETP) was measured in platelet rich plasma (PRP) and platelets poor plasma (PPP) by Calibrated Automated Thrombogram (CAT) assay. Endothelium-dependent vasodilation was assessed in isolated aortic rings by concentration-relaxation curves in response to acetylcholine (ACh). Results AngII-infused HO-1indLysMcre had decreased blood pressure values and improved endothelial function as compared to LysMcre controls. IVM revealed reduced leukocyte rolling and adhesion to the vascular endothelium in AngII infused HO-1indLysMcre mice compared to controls, paralleled by reduced expression of NOX-2 mediated oxidative stress and vascular inflammation in AngII-induced arterial hypertension by decreasing VCAM-1, CCR2 and MCP-1 expression. mRNA analysis revealed an increased expression of BLVRA in liver, spleen, heart and aortic tissues in response to AngII, which was higher in HO-1indLysMcre mice than in controls. By CAT assay we registered a decrease ETP in PPP and PRP in HO-1ind mice infused with AngII compatible with less abundance of inflammatory platelets, potentially regulated by BLVRA activity. This was supported by increased in bilirubin levels in response to AngII, which was higher in HO-1indLysMcre mice than in controls. Conclusion Myeloid cell specific overexpression of HO-1 confers anti-inflammatory protection to the vasculature in AngII induced hypertension. This effect is, at least in part, mediated by BLVRA. Funding Acknowledgement Type of funding sources: None.

Structure, conformational landscape and UV-induced selective rotamerization of 2-aminoacetanilide

The molecular structure, conformational space and UV-induced rotamerization and decarbonylation of 2-aminoacetanilide (2AA) were investigated by matrix isolation infrared spectroscopy and quantum chemical electronic structure calculations. The compound was isolated in a cryogenic (15 K) argon matrix, and four conformers were spectroscopically identified: two trans-amide (OCNH dihedral ∼ 180°) conformers (trans-I and trans-II), and two higher-energy cis-amide (OCNH dihedral ∼ 0°) conformers (cis-I and cis-II). These four conformers were found to be present in the as-deposited matrix of 2AA in a population ratio matching well that predicted by the calculations for the gas-phase equilibrium at the temperature of the vapor of the compound before deposition (60 °C = 333.15 K). The calculations predicted also the existence of an additional higher-energy trans-amide conformer (trans-III) which was not observed experimentally. In situ broadband UV irradiation (λ > 235 nm) of the matrix-isolated compound was found to induce selective conversion of conformer trans-I into conformer trans-II, in a few minutes (55 % after 2 min. of irradiation; 70 % after 10 min.), while the populations of the cis-amide conformers did not change. Prolonged UV irradiation was found to result in decomposition of the compound, leading to generation of carbon monoxide and 2-amine-N-methylaniline. The infrared spectra of the experimentally relevant conformers of 2AA were interpreted and assigned with help of normal coordinate analysis, and the different behavior of the conformers of 2AA upon UV-irradiation of the argon matrix was explained with help of time-dependent DFT (TD-DFT) calculations.

The Nuclear Translocation of Heme Oxygenase-1 in Human Diseases.

Heme oxygenase-1 (HO-1) is a rate-limiting enzyme in the degradation of heme to generate carbon monoxide (CO), free iron and biliverdin, which could then be converted to bilirubin by biliverdin reductase. HO-1 exhibits cytoprotective effects of anti-apoptosis, anti-oxidation, and anti-inflammation via these byproducts generated during the above process. In the last few years, despite the canonical function of HO-1 and possible biological significance of its byproducts, a noncanonical function, through which HO-1 exhibits functions in diseases independent of its enzyme activity, also has been reported. In this review, the noncanonical functions of HO-1 and its translocation in other subcellular compartments are summarized. More importantly, we emphasize the critical role of HO-1 nuclear translocation in human diseases. Intriguingly, this translocation was linked to tumorigenesis and tumor progression in lung, prostate, head, and neck squamous cell carcinomas and chronic myeloid leukemia. Given the importance of HO-1 nuclear translocation in human diseases, nuclear HO-1 as a novel target might be attractive for the prevention and treatment of human diseases.

Novel Function for Bilirubin as a Metabolic Signaling Molecule: Implications for Kidney Diseases.

Bilirubin is the end product of the catabolism of heme via the heme oxygenase pathway. Heme oxygenase generates carbon monoxide (CO) and biliverdin from the breakdown of heme, and biliverdin is rapidly reduced to bilirubin by the enzyme biliverdin reductase (BVR). Bilirubin has long been thought of as a toxic product that is only relevant to health when blood levels are severely elevated, such as in clinical jaundice. The physiologic functions of bilirubin correlate with the growing body of evidence demonstrating the protective effects of serum bilirubin against cardiovascular and metabolic diseases. Although the correlative evidence suggests a protective effect of serum bilirubin against many diseases, the mechanism by which bilirubin offers protection against cardiovascular and metabolic diseases remains unanswered. We recently discovered a novel function for bilirubin as a signaling molecule capable of activating the peroxisome proliferator-activated receptor α (PPARα) transcription factor. This review summarizes the new finding of bilirubin as a signaling molecule and proposes several mechanisms by which this novel action of bilirubin may protect against cardiovascular and kidney diseases.

Conversion of carbon dioxide to carbon monoxide: Two-step chemical looping dry reforming using Ca2Fe2O5–Zr0.5Ce0.5O2 composite oxygen carriers

In this study, Zr0.5Ce0.5O2 (ZC) was used to improve the reactivity of Ca2Fe2O5 (CF) oxygen carriers (OCs) and alleviate sintering. The reactivity of modified OCs in Chemical looping dry reforming (CLDR) was explored using a thermogravimetric analyzer and a fixed-bed reactor, and the fresh and reacted OCs were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results revealed that CF6 (60 wt% CF + 40 wt% ZC) had the best reactivity. Owing to the addition of ZC, the carbon monoxide (CO) yield of CF6 was twice that of CF during carbon dioxide (CO2) oxidation, increasing from 72.3 mL/g to 138 mL/g. In the cyclic experiments, the CO yield from CO2 oxidation decreased from 138 mL/g in the first cycle to 34.3 mL/g in the fifth cycle and subsequently stabilized over the next 15 cycles. The decrease in cyclic performance is related to the sintering of the sample and the formation of a new phase, CaZrO3, which hindered the redox reaction in the sample. Although CF6 had a decreased cyclic performance, it still had a better reactivity than CF, which had a CO yield that was about 20% lower than that of CF6. The reason for the improvement is that ZC improved the dispersibility of CF. After 20 cycles, the generation of CO was facilitated by extending the reduction time of the OC, and the CO yield increased from 35 mL/g to 60 mL/g when the reduction time was doubled.