Reaction Mechanism Research Articles

Co-pyrolyzed biochar derived from microplastics and microalgae as peroxymonosulfate activator: Influence of microplastic types and analysis of systemic causes

This work investigated the catalytic activity of co-pyrolyzed biochar (MP-SBC) from microplastic (MP) and Spirulina biomass and its activation mechanism for peroxymonosulfate (PMS). Given that different types of MPs had varied effects on the properties of biochar, polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS), and polylactic acid (PLA) were chosen as MP feedstocks. The results showed that the four kinds of MP-SBCs activated PMS more efficiently than the pristine algal-based biochar (SBC), with 100 % of the acetaminophen (ACT) degraded within 20 min. Based on the reaction mechanism analysis, the main pathways for the degradation of ACT by SBC and MP-SBC activated PMS were both non-radical pathways, and ACT was also efficiently degraded by the synergistic effect of 1O2 and electron transport pathway (ETP). Moreover, it was found that the microplastic modification could significantly enhance the efficacy of SBCs in triggering the non-radical pathway. Establishing the correlation between the structural features of BC and the degradation mechanism (active species contribution) revealed that the persistent free radicals (PFRs), defective structures, CO, and graphite N are all potential active sites. Thereinto, PFRs are the active sites for radicals, defects are the active sites for 1O2 production, and CO, defects, and graphitic N are the active sites for ETP. Overall, this work provides an innovative approach for designing efficient biochar-based catalysts for environmental remediation.

Synthesis of Saxitoxin Biosynthetic Intermediates: Reveal the Mechanism for Formation of its Tricyclic Skeleton in Biosynthesis.

The synthesis and biosynthesis of the complex saxitoxin (STX) structure have garnered significant interest. Previously, we hypothesized that the tricyclic skeleton of STX originates from the monocyclic precursor 11-hydroxy-IntC'2 during biosynthesis, although direct evidence has been lacking. In this study, we identified conditions to synthesize a proposed tricyclic biosynthetic intermediate, 12,12-dideoxy-decarbamoyloxySTX (dd-doSTX), along with its 6-epimer (6-epi-dd-doSTX) and a bicyclic compound, in a single step from di-Boc protected 11-hydroxy-IntC'2. The reaction mechanism involves successive aza-Michael addition of a guanidino amine to the conjugated olefin. Notably, both dd-doSTX and 6-epi-dd-doSTX were detected in a toxin-producing cyanobacterium, suggesting that the biosynthetic enzymes may generate these compounds via similar mechanisms.

Construction of Spiro Systems from Tetrathiafulvalene Derivatives by a Pinacol‐like Rearrangement

An efficient and generalized pinacol‐like rearrangement of tetrathiafulvalene (TTF) derivatives has been achieved using 2, 2, 6, 6‐tetramethylpiperidine oxide (TEMPO) as a key reagent, in place of a traditional metal catalyst. Examination of numerous TTF derivatives demonstrates the reaction's exceptional tolerance to a variety of substituents, achieving an overall yield of up to 97%. The optimization of reaction conditions and evaluation of reaction applicability were achieved by varying factors such as the redox potential (E11/2) of the substrate molecule, substituent type, substituent position, number of substituents, and structural symmetry. Additionally, the reaction mechanism was explored using isotopic labeling, real‐time monitoring UV‐Vis absorption spectroscopy, and X‐ray diffraction (XRD) analysis. Specifically, TTF is oxidized to TTF+• by p‐toluenesulfonic acid (TsOH·H2O). TTF+• subsequently reacts with TEMPO and H2O to form a pinacol‐like intermediate, which undergoes a rearrangement to release a 2, 2, 6, 6‐tetramethylpiperidin‐1‐ol (TEMPOH) molecule, forming the rearranged product as a hydrogenated cation, this intermediate undergoes deprotonation, leading to the formation of the final spiro product. This investigation led to the identification of a class of reactions for the efficient conversion of TTF derivatives into their spiro products via pinacol‐like rearrangement reaction.

Revealing the flame inhibition effect of phytic acid (PA) by PIV measurements and detailed chemical kinetic modeling of counterflow CH4/PA/air flames

As industrialization continues to deepen, polymers have become ubiquitous in daily life. However, their flammable characteristics pose significant safety risks. Therefore, supporting the global goal of sustainable development necessitates the development of high-performance, environmentally friendly flame retardants. Biomass phytic acid (PA) has emerged as a promising option because of its high phosphorus content and excellent biocompatibility. However, its combustion behaviors and chemical kinetic mechanisms remain unclear. In this study, quantum chemical calculation methods were used to construct a detailed PA chemical reaction kinetic model. A series of experiments were conducted to validate the model and evaluate PA's flame suppression effect. Utilizing a counterflow flame burner and particle image velocimetry (PIV), the inhibitory effect of various PA concentrations was examined based on the laminar flame speed of CH4/PA/Air mixture. The results revealed that a merely 0.2 % addition of PA could reduce the laminar flame speed by 38.9 %, demonstrating its significant flame suppression effect. Building on the foundational GRI-Mech 3.0 and integrating PA's pyrolysis and reaction mechanism, this study developed for the first time a detailed chemical model of CH4/PA/Air combustion. This model integrated PA's thermal decomposition module and thermodynamic data via ab-initio quantum chemical calculations, thereby accurately predicting global kinetic indicators such as laminar flame speed. Results suggested that the key reactions, such as PO2+H + M→HOPO + M, HOPO2+H→PO2+H2O, and HOPO + OH→PO2+H2O primarily influenced the laminar flame speed. Moreover, the CFD simulation elucidated the complex interaction between PA and flame structures. A detailed analysis of the spatial distribution of key parameters such as temperature, combustion radicals, and effective inhibition radicals unveiled the PA's flame suppression mechanism in support of the practical application of this eco-friendly flame retardant.

Practical Considerations for Understanding Surface Reaction Mechanisms Involved in Heterogeneous Catalysis

Practical Considerations for Understanding Surface Reaction Mechanisms Involved in Heterogeneous Catalysis

Crystal Structure and Mutagenesis of an XYP Subfamily Cyclodipeptide Synthase Reveal Key Determinants of Enzyme Activity and Substrate Specificity.

Cyclodipeptide synthases (CDPSs) catalyze the synthesis of diverse cyclodipeptides (CDPs) by utilizing two aminoacyl-tRNA (aa-tRNA) substrates in a sequential ping-pong reaction mechanism. Numerous CDPSs have been characterized to provide precursors for diketopiperazines (DKPs) with diverse structural characteristics and biological activities. BcmA, belonging to the XYP subfamily, is a cyclo(l-Ile-l-Leu)-synthesizing CDPS involved in the biosynthesis of the antibiotic bicyclomycin. The structural basis and determinants influencing BcmA enzyme activity and substrate selectivity are not well understood. Here, we report the crystal structure of SsBcmA from Streptomyces sapporonensis. Through structural comparison and systematic site-directed mutagenesis, we highlight the significance of key residues located in the aminoacyl-binding pocket for enzyme activity and substrate specificity. In particular, the nonconserved residues D161 and K165 in pocket P2 are essential for the activity of SsBcmA without significant alteration of the substrate specificity, while the conserved residues F158 as well as F210 and S211 in P2 are responsible for determining substrate selectivity. These findings facilitate the understanding of how CDPSs selectively accept hydrophobic substrates and provide additional clues for the engineering of these enzymes for synthetic biology applications.

Electrochemical Deconstructive Methoxylation of Arylalcohols-A Synthetic and Mechanistic Investigation.

Herein, we report a mechanistic investigation of a recently developed electrochemical method for the deconstructive methoxylation of arylalcohols. A combination of synthetic, electroanalytical, and computational experiments have been performed to gain a deeper understanding of the reaction mechanism and the structural requirements for fragmentation to occur. It was found that 2-arylalcohols undergo anodic oxidation to form the corresponding aromatic radical cations, which fragment to form oxocarbenium ions and benzylic radical intermediates via mesolytic cleavage, with further anodic oxidation and trapping of the benzylic carbocation with methanol to generate the observed methyl ether products. It was also found that the electrochemical fragmentation of 2-arylalkanols is promoted by structural features that stabilize the oxocarbenium ions and/or benzylic radical intermediates formed upon mesolytic cleavage of the aromatic radical cations. With an enhanced understanding of the reaction mechanism and the structural features that promote fragmentation, it is anticipated that alternative electrosynthetic transformations will be developed that utilize this powerful, yet underdeveloped, mode of substrate activation.

Staggered distribution structure Cu-Mn catalysts for mitigating smoke and gas toxicity in combustion: Unravelling mechanistic insight through operando studies

The integration of flame retardancy and environmental friendliness can be achieved by designing cost-effective, stable, and efficient catalysts to reduce smoke and toxicity during the combustion of polymeric materials. This work reports the development of non-precious metal catalysts for thermoplastic polyurethanes (TPU), which exhibit a significant reduction in smoke and gases toxicity while providing flame retardancy. The use of MgB2 as a support enables the in-situ growth of highly efficient Cu-Mn based catalysts, resulting in a remarkable 51.5 % decrease in total smoke release and a 49.1 % reduction in peak rate of CO generation of TPU according to cone calorimeter test results. Furthermore, Cu-Mn/MgB2 demonstrates an impressive 83.1 % reduction in total CO production rate during the steady-state tube furnace test. Additionally, density functional theory is employed to analyze the binding energy between catalysts and TPU as well as the adsorption energy of gases. This elucidates the rational reaction mechanism behind the catalyst and smoke inhibiting process. By combining transition metal oxide catalyzed CO oxidation reaction with polymeric material combustion, this study presents a promising approach for efficient smoke suppression with potential applications.

Levofloxacin degradation in electro-Fenton system with FeMn@GF composite electrode

In this work, a one-step solvent-thermal approach was used to synthesize an Mn-doped Fe3O4 modified graphite felt (GF) composite electrode material (FeMn@GF), which was then used as the cathode in an Electro-Fenton (EF) system. The levofloxacin (LEV) in wastewater can be successfully removed by the EF system, which can produce and activate H2O2 in situ. The successful fabrication of the FeMn@GF composite electrode was confirmed by employing the characterization techniques of Scanning Electron Microscope, X-ray Diffraction, and X-ray Photoelectron Spectroscopy. Additionally, the electrochemical performance test was conducted. The FeMn@GF composite electrode demonstrated a greater electrochemical activity and a more robust electronic transmission ability. The LEV degradation experiment demonstrated reached 98.9 % that under ambient temperature conditions, within 120 minutes, given initial LEV concentration of 20 mg·L −1, Na2SO4 concentration of 50 mM, applied voltage of 3.0 V, initial pH value of 3, and aeration rate of 3.0 L·min −1.The highest leaching quantities of Fe and Mn were 1.294 mg·L−1 and 0.675 mg·L−1, respectively, while the removal effectiveness of LEV remained at 85.2 % after five cycles. Experiments using radical quenching revealed that the main active species were ·OH. The reaction mechanism of the EF system with FeMn@GF as the cathode (FeMn@GF-EF) and the degradation pathway of LEV were investigated.

Alkylsulfonic acid functionalized aluminoborate: A highly efficient and regioselective solid acid catalyst for ring-opening addition of epoxide under solvent-free condition

Functionalized solid acid material has more accessible active surface and therefore is usually considered as an important substitute for conventional liquid mineral acid. In this work, a novel alkylsulfonic acid functionalized porous aluminoborate molecular sieve (PKU-1) has been prepared through 3-step post-synthetic method, and the high-density acidic sites were tailored and comprehensively characterized by various measurements. These acidity-controllable active sites exhibit high activity and specific regioselectivity towards alcoholysis reaction for the solvent-free production of methoxyl alcohol, and turnover frequency reaches ∼1000 h–1, which is much superior to previous reports. Comprehensive characterizations indicate catalytic centers exclusively come from –SO3H acid sites, rather than other type of Brönsted or Lewis acid sites. A plausible reaction mechanism was proposed to interpret the key role of –SO3H active sites on alcoholysis reaction based on the related experimental results. This work offers a promising solution to generate the controllable acidity and provides an available candidate in the environmentally benign catalysis for selective synthesis of some value-added compounds.

A Review on the Gas‐Phase Modeling Study of Aluminum Combustion in Various Environments

AbstractAluminum combustion is an area of intense research due to its wide‐ranging applications in the aerospace, automotive, energy storage carrier and defense industries. Gas‐phase reaction mechanism plays an important role on the prediction of the combustion intermediates and final products, which can significantly affect the combustion heat releases and combustion organization forms. In recent years, researchers have developed some gas‐phase reaction mechanisms to predict the combustion phenomenon and behavior of aluminum in different environments. This review aims to provide an overview of the current state of the art in gas‐phase modeling study on aluminum combustion with various oxidizers, including oxygen, steam, carbon dioxide and so on. The primary oxidation reactions of aluminum were concluded, and the rate coefficients of these reactions were also reviewed and compared in this work. Besides, the simulations by using the gas‐phase reaction mechanisms were reviewed and the main oxidation reaction pathways of aluminum with various oxidizers were analyzed based on modeling analysis results. Combining phase change reactions and surface reactions, gas‐phase reaction mechanism will become more important for prediction the combustion speed, combustion temperature and combustion mode of aluminum in future.

Nighttime chemistry of furanoids and terpenes: Temperature dependent kinetics with NO3 radicals and insights into the reaction mechanism

In this study, the gas phase reaction of NO3 radical with three furanoids, furan (F), 2-methylfuran (2-MF) and 2,5-dimethylfuran (2,5-DMF) were investigated using a relative rate method in a temperature regulated atmospheric simulation chamber (THALAMOS). As part of this study, the temperature dependence of two monoterpenes, α-pinene (α-P) and 2-carene (2-C), that were used as reference molecules, is also reported. The kinetic measurements were performed in the range of 263–373 K, atmospheric pressure using zero air as bath gas. The reaction was followed using Selected ion flow tube mass spectrometry (SIFT-MS) to monitor in real time the mixing ratios of the investigated species. The corresponding Arrhenius expressions obtained were:kα−P+NO3(263−378K)=(1.32±0.16)×10−12×e462±70Tcm3molecule‐1s‐1.k2−C+NO3296–433K=8.77±2.71×10−13×e904±96Tcm3molecule‐1s‐1.kF+NO3263−353K=7.55±1.96×10−13×e254±79Tcm3molecule‐1s‐1.k2−MF+NO3263−373K=7.76±2.62×10−13×e922±262Tcm3molecule‐1s‐1.k2,5−DMF+NO3298–353K=2.58±0.77×10−13×e1692±136Tcm3molecule‐1s‐1.Where the estimated uncertainties include the 1σ precision of the fit and the estimated uncertainty in the precision of the Arhenius fit of the reference compound. In the case of furanoids, the negative temperature-dependence of the rate coefficients shows that the reaction mechanism is complex, indicating that the reaction involves the formation of an adduct that could lead either to NO3 addition to the double bond, as well as, in the case of 2-MF and 2,5-DMF, the H-abstraction from the methyl group attached to the ring. In addition to the kinetics measurements, the major products formed from the reaction of furan and 2,5-DMF with NO3 were studied. The two identified products from the reaction of furan with NO3, were 3H-furan-2-one (C4H4O2) and 2-butenedial (C4H4O2), formed by NO3 addition to the double bond of the furan ring. 3-Hexene-2,5-dione (C6H8O2) and 5-methylfurfural (C6H6O2) are the two major products of 2,5-DMF reaction with NO3, linked to the addition and abstraction pathways, respectively. Considering that 5-methylfurfural is the only primary product of the H elimination pathway of 2,5-DMF, the determination of its formation yields as a function of temperature, allowed us to extract the temperature dependence of the rate coefficients of the abstraction and addition pathways.Overall, the NO3 oxidation of the studied furanoids, is expected to be the dominant tropospheric loss process, in the studied temperature range.

Visible‐Light‐Mediated Selective Fluorine Incorporation by Anthraquinone‐Based Covalent Organic Framework as Recyclable Photocatalyst

Covalent organic frameworks (COFs) serve as an excellent foundation for heterogeneous photocatalysis. Herein, we synthesized an anthraquinone‐based COF (TpAQ) on a gram scale via a mechanochemical grinding pathway. This COF was employed as a visible‐light‐harvesting photocatalyst for selective fluorination of benzylic C‐H bonds and perfluoroalkylation of arenes. The carbonyl core in the anthraquinone linker facilitated benzylic fluorination through a hydrogen atom transfer (HAT) pathway. Control experiments and photophysical analysis were conducted to gain deeper insight into the reaction mechanism. The recyclability up to 5th cycle without significant loss of the yield (> 90%) highlighted the robustness of the catalyst. This reaction strategy was also executed on a gram scale to validate the scalability of the protocol.

Comparison of the Reaction Characteristics of Different Fuels in the Supercritical Multicomponent Thermal Fluid Generation Process

Supercritical multicomponent thermal fluid technology is a new technology with obvious advantages in offshore heavy oil recovery. However, there is currently insufficient understanding of the generation characteristics of the supercritical multicomponent thermal fluid, which is not conducive to the promotion and application of this technology. In order to improve the economic benefits and applicability of the supercritical multicomponent thermal fluid thermal recovery technology, this article reports on indoor supercritical multicomponent thermal fluid generation experiments and compares the reaction characteristics of different fuels in the supercritical multicomponent thermal fluid generation process. The research results indicate that the main components of the products obtained from the supercritical water–crude oil/diesel reaction are similar. Compared to the supercritical water–crude oil reaction, the total enthalpy value of the supercritical multicomponent thermal fluid generated by the supercritical water–diesel reaction is higher, and the specific enthalpy is lower. When the thermal efficiency of the boiler is the same, the energy equilibrium concentration of crude oil is lower than that of diesel. The feasibility of using crude oil instead of diesel to prepare supercritical multicomponent thermal fluids is analyzed from three aspects: reaction mechanism, economic benefits, and technical conditions. It is believed that using crude oil instead of diesel to prepare supercritical multicomponent thermal fluids has good feasibility.

In situ Cyclization of Aromatic Thioethers in Emissive Materials to Generate Phosphorescent Dibenzothiophenes

AbstractIn this contribution, we explored the photocyclization of thioethers to highly substituted dibenzothiophenes (DBT) using solely UV‐light without any need for additives. This cost‐effective, robust and environmentally friendly approach yielded phosphorescent compounds, which were characterized by X‐ray crystallography and state‐of‐the‐art photophysical methods. The resulting DBTs feature ultralong photoluminescence lifetimes and quantum yields close to unity in frozen glassy matrices. The reaction mechanism was elucidated in detail through a combination of quantum chemical calculations and experimental results, providing evidence that triplet states are involved in the cyclization process. Additionally, the photoreaction can also be induced within materials. For this purpose, the precursors were integrated into polymer films or polymer resins suitable for 3D printing. Irradiation of these polymeric objects allows motifs with ultralong phosphorescence to be irreversibly inscribed through the proceeding photocyclization. The in situ photogeneration of DBTs from aromatic thioethers overcomes the observed incompatibilities regarding solubility in polymer resins for 3D printing.

Capture and in-situ conversion of low-concentration CO2 over robust poly(ionic liquid)@porous carbon nanocomposites under green, co-catalyst- and solvent-free conditions

The development of advanced materials with dual functionalities for the capture of low-concentration CO2 and its in-situ conversion into value-added chemicals under mild and green conditions holds significant practical importance. In this study, we present a facile pyrolysis of fluid precursors followed by an in-situ polymerization strategy for preparing poly(ionic liquid)@porous carbon nanocomposites (PIL-Brx@Zn-CTM), which possess multiple active sites including Lewis acidic Zn2+, Lewis basic N, and nucleophilic Br– groups. Subsequently, we investigate their potential application in the efficient capture and conversion of low-concentration CO2 into cyclic carbonates. The influence of PIL-Brx@Zn-CTM structures and technological conditions on the cycloaddition reaction between low-concentration CO2 (15 % CO2 and 85 % N2) and epichlorohydrin was examined. The PIL-Br1.0@Zn-CTM nanocomposite was determined to be the most suitable catalyst, resulting in a 94 % yield of chloropropene carbonate with 99 % selectivity under mild, co-catalyst-, and solvent-free conditions. Furthermore, the reusability of PIL-Br1.0@Zn-CTM and its substrate scope were investigated. The PIL-Br1.0@Zn-CTM exhibited sustained high activity without a significant decrease after seven cycles of reuse, and it also demonstrated excellent catalytic activity for cycloaddition reactions involving low-concentration CO2 with various substituted epoxides. Finally, a mechanism for the cycloaddition reaction catalyzed by the PIL-Brx@Zn-CTM nanocomposite was proposed.

Enhancing the high temperature resistance of nanocomposite materials through dimethyl methyl phosphate impregnation‐coating treatment

AbstractIn order to enhance the thermal stability of polyvinyl alcohol (PVA), a modification scheme involving a dimethyl methyl phosphate (DMMP) impregnation‐coating treatment was adopted in this article. Initially, the interfacial compatibility of DMMP with PVA was characterized using scanning electron microscopy (SEM), inductively coupled plasma spectroscopy, elemental analysis and Fourier transform infrared spectroscopy (FTIR). Subsequently, the pyrolysis and combustion properties of DMMP‐coated PVA were evaluated via non‐isothermal thermogravimetric experiments and cone calorimeter tests. The pyrolysis products were then analyzed using a combination of thermogravimetric infrared chromatography and pyrolysis gas chromatography/mass spectrometry (Py‐GC/MS). Finally, a reaction model function closer to the actual co‐pyrolysis mechanism at high temperatures was established through thermal kinetics. The results indicated that the impregnation‐coating treatment could effectively distribute the DMMP molecules on the surfaces of PVA particles. Meanwhile, the DMMP coating could clearly slow the peak degradation rate of PVA grains and inhibit the combustion of PVA under fire conditions. Furthermore, the pyrolysis of DMMP‐coated PVA resulted in the formation of over 40 distinct compounds. The kinetic analysis revealed that the reaction model function established in this article could better characterize the actual reaction mechanism of the co‐pyrolysis of DMMP and PVA.

Onset Reaction Mechanism of Cr and S Poisoning on Perovskite Oxide Surfaces

Onset Reaction Mechanism of Cr and S Poisoning on Perovskite Oxide Surfaces

Oxidative degradation of chitosan by Fe-MCM-41 heterogeneous Fenton-like system

We herein disclosed an efficient multiphase Fenton-like catalytic system for oxidative degradation of chitosan. By utilizing Fe-MCM-41, featured with regular mesoporous structure and high specific surface area, the activation efficiency of H2O2 was significantly enhanced and the chitosan degradation efficiency proved by 28.1% higher than the conventional system using H2O2 alone. Under optimized conditions (5 g/L chitosan, 0.5 g/L Fe-MCM-41, 0.16 mol/L CH3COOH, 0.86 mol/L H2O2, 50 °C, 140 min), the viscosity reduction rate of chitosan reached an impressive 98.2%. Among the catalysts tested, Fe-MCM-41 with a loading factor of x = 0.12 demonstrated optimal degradation performance. After four recycles, the degradation efficiency maintained > 93.6%, demonstrating its excellent stability and recyclability for potential industrial applications. Kinetic studies provided further elucidation of the reaction mechanism, which indicated that the degradation process of chitosan followed a first-order kinetic model, with an apparent activation energy (Ea) of 48.91 kJ/mol. This novel and efficient strategy for chitosan degradation, addressed the challenges of catalyst recovery and secondary pollution typically associated with traditional Fenton systems, and posed broad application potential for polysaccharide material processing.

Recent Advances in Photocatalytic Degradation of Tetracycline Antibiotics

China is a significant global producer and consumer of pesticides and antibiotics, with their excessive use leading to substantial water pollution that poses challenges for subsequent treatment. Photocatalytic degradation, leveraging renewable solar energy, presents an effective approach for decomposing organic pollutants and reducing residual contaminant levels in water bodies. This approach represents one effective way for addressing environmental challenges. This paper classifies representative photocatalytic materials by structural design and degradation principles including MOFs (Metal–Organic Frameworks), metal- and nonmetal-doped, mesoporous material-loaded, carbon quantum dot-modified, floatation-based, and heterojunction photocatalysts. We also discuss research on degradation pathways and reaction mechanisms for antibiotics. Of particular importance are several key factors influencing degradation efficiency, which are summarized within this work. These include the separation and charge transfer rate of catalyst surface carriers, and the wide-spectrum response capabilities of photocatalysts, as well as persulfate activation efficiency. Furthermore, emphasis is placed on the significant role played by intrinsic driving forces such as built-in electric fields within catalytic systems. Moreover, this paper introduces several promising composite-structure photocatalytic technologies from both composite-structure perspectives (e.g., Aerogel-based composites) and composite-method perspectives (e.g., the molecularly imprinted synthesis method). We also discuss their latest development status, along with future prospects, presenting valuable insights for pollutant degradation targets. This work aims to facilitate the design of efficient photocatalytic materials, while providing valuable theoretical references for environmental governance technologies.