Formation Of Functional Groups Research Articles

Synthesis of nitrogen-doped hierarchical porous carbons from peanut shell as a promising electrode material for high-performance supercapacitors

Abstract A synthetic strategy for preparing nitrogen (N)-doped porous carbons with high electrochemical performance is proposed using peanut shell as the raw material and melamine as the dopant. The as-prepared activated carbons exhibit a hierarchical porous structure with abundant micropores and mesopores, and the mesopores are mainly in the pore size range of 2 and 5 nm. The N-doping leads to the formation of nitrogen-containing functional groups on the surface of the activated carbons. The optimum sample in this work is obtained at a melamine to activated carbon mass ratio of 2:1 (NHAC-2), which possesses a high surface area of 2014.6 m2/g. The assembled NHAC-2 based electrode delivers a high specific capacitance of 310.59 F/g at the current density of 0.5 A/g in the three-electrode system. In the two-electrode system, the symmetric supercapacitor assembled by NHAC-2 demonstrates a high specific capacitance of 300.6 F/g at 0.5 A/g and 246.4 F/g at 10 A/g, exhibiting high capacitance retention. NHAC-2 also exhibits excellent cycle stability with the capacitance retention of 90.14% after 5,000 cycles at the current density of 2 A/g.

Glassy Carbon Electrode Electromodification in the Presence of Organic Monomers: Electropolymerization versus Activation.

Several reports in the literature deal with the modification of glassy carbon electrode (GCE) surface via electropolymerization of some organic monomers, particularly p-aminobenzenesulfonic acid (p-ABSA) and l-cysteine using intensive oxidative conditions, and attributed the improved electrocatalytic activities toward various analytes to the formation of the electropolymerized layer. What is the real cause for this improvement in electrocatalytic activity? Is it because of the electrochemical activation process of GCE or electropolymerization? Combining a set of surface and electrochemical characterization techniques, we first showed that the electrochemical peaks previously assigned in many reports to electropolymerization processes at the surface of GCE correspond to electrochemical activation of the GCE surface. We further demonstrated that the anodization of GCE at high voltage causes activation of its surface and the formation of surface functional groups (SFGs). In fact, those SFGs are found to be the main reason for the enhancement in electrocatalytic activity of the activated GCE (AGCE). The surface features of the modified electrodes were characterized by Raman spectroscopy, attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The electrochemical behavior was investigated using cyclic voltammetry (CV). The analytical performance of AGCE toward dopamine (DA) was assessed using differential pulse voltammetry (DPV). As compared to the previously reported dopamine electrochemical sensors assuming such electropolymerization processes, the AGCE showed analytical performance practically similar to that of these sensors. This further confirms that the enhancement in electrocatalytic activity is due to the electrochemical activation of the GCE surface.

Ability of Trichoderma hamatum Isolated from Plastics-Polluted Environments to Attack Petroleum-Based, Synthetic Polymer Films

Microorganisms colonizing plastic waste material collected in composting-, landfill-, and anaerobic digestion plants were isolated to obtain novel strains maximally adapted to the degradation of plastics due to long-term contact with plastic polymers. Twenty-six bacterial strains were isolated and identified by the 16 S rRNA method, and eighteen strains of yeasts and fungi using 18 S rRNA and the internal transcribed spacer ITS sequencing of the 18 S rRNA gene. In selected strains, the ability to degrade linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), polystyrene (PS), and polyvinyl chloride (PVC) was tested in aerobic liquid-medium cultures. An oxidative, two-step pretreatment of LLDPE and LDPE using γ- or UV-irradiation followed by a high-temperature treatment was carried out, and the pretreated plastics were also included in the degradation experiments. The respective weight losses after biodegradation by Trichoderma hamatum were: virgin and γ/T90-pretreated LLDPE (2.2 ± 1.2 and 3.9 ± 0.5%), virgin and UV/T60-pretreated LDPE (0.5 ± 0.4 and 1.3 ± 0.4%), and virgin PS (0.9 ± 0.4%). The Fourier transform infrared spectroscopy (FTIR) analysis showed that during the treatment of pretreated LLDPE, T. hamatum attacked low molecular weight LLDPE oligomers, reducing the functional groups (carbonyl C = O), which was paralleled by a slight increase of the molar mass of pretreated LLDPE and a decrease of the dispersity index, as demonstrated by gel permeation chromatography (GPC). Thermogravimetric analysis (TGA) highlighted the formation of functional groups on LLDPE due to polymer pretreatment that favored fungal attack at the polymer surface. The results provide insight into microbial consortia that spontaneously colonize the surface of plastics in various environments and their capability to attack plastic polymers.

Alterations of asphaltenes chemical structure due to carbon dioxide injection

Asphaltenes precipitation during carbon dioxide injection to enhance recovery has been considered as one of the major challenges in the tertiary production phase. The effects of CO2 injection on asphaltenes chemical structure and stability in the matrix has not been fully understood yet. The present study aims to characterize asphaltenes structural alterations in the presence of CO2 at high temperature and pressure and then elaborates the mechanism in which these changes affect asphaltenes stability in the matrix. The chemical structure of four precipitated asphaltenes in the presence and absence of CO2 were characterized and compared. These results were coupled with the results of the stability assessment to determine the effects of structural alteration on asphaltenes stability in crude oil. Infrared (IR) spectroscopy results demonstrated the formation of amide functional group upon CO2 injection to the model oil. The precursor of such an observation is characterized to be the reaction of CO2 with amine functional group of the asphaltenes sample. Such a reaction led to the decrease of asphaltenes stability in the model oil sample. The results of the present study suggest that asphaltenes can be destabilized in the oil matrix through both chemical reactions and physical interactions. The presence of chemical functional groups that can react with CO2 in the reservoir conditions is the primary trigger to initiate asphaltenes destabilization. These findings can be used to further research asphaltenes disturbing mechanisms at the molecular level and scale them up to understand asphaltenes physical behaviors during CO2 injection.

Influence of Biochar Composition and Micro-Structure on the Denitration of Flue Gases at High Temperature

Biochar materials are good reducers of nitrogen oxides. The composition and structure of biochar affect significantly its ability to reduce C–NO. In order to study the denitration of flue gases by biochar at high temperature, three kinds of biochar (bamboo charcoal (BC), rice husk ash (RHA), and straw charcoal (SC)) were mixed with cement raw meal in a fixed-bed quartz reactor at the temperature of 800–900 °C and O2 concentration of 0.5%–2%. The results showed that the initial denitration rate of BC was higher than that of RHA, and that of SC was the lowest. RHA had the largest specific surface area, and BC the smallest. The elements C, N, and O and the functional groups of the three types of biochar had a greater influence on the denitration rate than their structures. The denitration rate decreased faster as the O/C ratio increased, and the increase in the relative content of the N element induced the formation of nitrogen-containing functional groups catalyzing C–NO reduction. The content of the C–C bond affected directly the rate of denitration, and both (NCO)x and C–O bonds had a positive effect on the reduction capability of biochar. It can be concluded that the composition of biochar has an important effect on the reduction of C–NO.

Roles of oxygen and Mn (IV) oxide in abiotic formation of humic substances by oxidative polymerization of polyphenol and amino acid

Abstract The metal oxide-facilitated transformation of polyphenols and amino acids to humic substances (HS) is an essential process in soil and compost maturing processes. The objective of this research was to examine the specific roles of MnO2 and O2 in the formation of HS by oxidative polymerization of catechin (a polyphenol) and glycine (an amino acid). The results demonstrated that large amounts of fulvic acid (FA) and humic acid (HA) only formed in the presence of O2, while the presence of both O2 and MnO2 significantly enhanced HA formation, demonstrating their synergistic effects. The size of HA only increased in the presence of MnO2, but MnO2 without O2 was unable to convert FA to HA. Two-dimensional correlation spectroscopy results suggested that the sequence of the formation of HA functional groups was: C–OH in carboxylic acids >C–O in phenolic-OH > amide II and aromatic C–C > amide and carboxylate C=O > COO− >NH > hydrogen bond. Finally, XPS spectra of the MnO2 before and after the reaction showed that the Mn(IV) content decreased from >99% to 89.98% and 80.89% while the Mn(III) content increased from

Phosphorus-modulated controllably oxidized carbon nanotube architectures for the ultrahigh energy density of pseudocapacitive capacitors

Construction of heteroatoms modification of carbon nanotubes (CNT) is an attractive strategy to improve the stability and the energy density of advanced supercapacitors. Herein, the hierarchical phosphorus (P) -doped and ozonized CNT architectures (POCA) are prepared by the combination of simple ozonation, self-assembly and thermal activation approaches. The highly oxidative ozone gas would continuously etch unstable oxygen species and weaken the p-type effect of carbon nanotubes; while P atoms doping further modulates the electronic structure. As confirmed by spectroscopic and microscopic analysis, POCA exhibits a macroporous structure for fast ion diffusion and the formation of new functional groups (P–O, C–P) as the dominant active-sites for energy storage. The specific capacitance for POCA is reached up to 185.4 F g−1 at 0.5 A g−1 in a three-electrode configuration, which is superior to other control samples due to the additionally pseudocapacitive contribution. Furthermore, the symmetric POCA//POCA supercapacitor yields a high energy density of 19.2 Wh kg−1 in 1 M Na2SO4 with a wide potential window of 1.8 V due to the synergistic effect of the hierarchical architecture and modulated surface chemistry.

The Effect of Waste Engine Oil and Waste Polyethylene on UV Aging Resistance of Asphalt

Waste engine oil (WEO) and waste polyethylene (WPE) are two common wastes, which are easy to pollute the environment. As the primary material in road construction, natural asphalt is a non-renewable energy source and asphalt is vulnerable to ultraviolet (UV) radiation during the service life. It results in degradation of asphalt pavement performance. In this paper, 2 wt % to 8 wt % of WEO and WPE were used to modify asphalts and the UV aging simulation experiment was carried out. The physical parameters of asphalts before the UV aging experiment show that the asphalt containing 4 wt % WPE and 6 wt % WEO mixture (4 wt % WPE + 6 wt % WEO) has similar physical properties with that of the matrix asphalt. Besides, gel permeation chromatography (GPC) verifies that the molecular weight distribution of the asphalt containing 4 wt % WPE + 6 wt % WEO is close to that of the matrix asphalt. The storage stability test shows that 4 wt % WPE + 6 wt % WEO has good compatibility with the matrix asphalt. The functional groups and micro-morphology of asphalts before and after the UV aging experiment were investigated by Fourier transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM). FTIR results display that 4 wt % WPE + 6 wt % WEO can effectively reduce the formation of carbonyl and sulfoxide functional groups. AFM shows that 4 wt % WPE + 6 wt % WEO can also retard the formation of a “bee-like” structure in asphalt after the UV aging experiment. Based on the above results, it can be concluded that WEO and WPE mixture can replace part of asphalt and improve the UV aging resistance of asphalt.

ZnO/Carbon xerogel photocatalysts by low-pressure plasma treatment, the role of the carbon substrate and its plasma functionalization

ZnO is known to be photocatalytic, but with limited performances due to the strong electron-hole recombination after irradiation. The integration of ZnO nanomaterials on a conductive and high surface area carbon substrate is thus a potential alternative to obtain a significant improvement of the photocatalytic performance. Moreover, the carbon functionalization is expected to have a significant role in the adsorption/degradation mechanisms of dye, due to the difference in wettability or surface charge.In this view, ZnO photocatalytic nanoparticles have been deposited on high surface area carbon xerogel substrate (CXG), using a new and original plasma process, consisting in the degradation of a solid organometallic directly on the carbon substrate (no gaseous precursor). In addition to the ZnO nanoparticle formation, the plasma treatment allows the carbon functionalization. The ZnO/CXG composite has been tested for the degradation of Rhodamine B (RhB) in aqueous media and compared with and O2 or NH3 plasma-treated xerogels (without nanoparticles) to identify the significant role of the substrate and its modification in the RhB adsorption and degradation mechanism.The high photocatalytic activity of ZnO/CXG composite is attributed to (i) the formation of small (8–10 nm) and well-crystallized ZnO nanoparticles anchored to the carbon substrate and (ii) to the modification of the xerogel surface chemistry. Indeed, O2 plasma treatment of the CXG promotes the generation of hydroxyl, carbonyl and carboxyl surface functional groups, which are polar and acidic, while the NH3 plasma treatment mainly leads to the formation of polar and basic amino groups. While both plasma treatments promote the formation of polar functional groups, which enhance the CXG wettability, the formation of acidic groups is identified as beneficial for the adsorption of the RhB dye, while basic groups are detrimental.

Enhanced adsorption of sulfamethoxazole from aqueous solution by Fe-impregnated graphited biochar

An increasing amount of antibiotics has been released into the aquatic environment and caused a serious threat to public health. In this study, a series of magnetic biochars (MBCs) were prepared via one-step graphitization and magnetization for sulfamethoxazole (SMX) removal. The effects of pyrolysis temperature and impregnated FeCl3 concentration on SMX adsorption were investigated. Characterization of MBC were carried out through SEM, BET, XRD, FTIR, Raman and XPS analyses. The performance for sulfamethoxazole removal was evaluated with the adsorption kinetics and isotherms studies, and the influence of pH, temperature, ion and NOM on SMX adsorption capacity was also examined in batch studies. The results show that the physicochemical properties of the MBCs were dominated by the pyrolysis temperatures and the iron weight ratio. The iron species in MBCs contributed significantly to the enhancement of SMX adsorptive capacity, including increasing the carbonization degree, promoting the formation of oxygen-rich functional groups and providing more adsorption sites. The prepared MBCs was proved to be highly efficient for SMX removal, and the 300-MBC800 was the optimal sorbent with the maximum adsorption capacity of 187.31 mg g−1, which was 5.3 times of the pristine biochar. The primary mechanisms for SMX adsorption include electrostatic interaction, π-π electron-donor-acceptor (EDA) interaction, hydrogen bonding, and Lewis acid-base electron interactions, mainly resulting from the graphitized structures and enriched functional groups on MBCs. This study demonstrated promise of MBC as an effective and environmentally friendly sorbent for removing SMX from wastewater with high adsorption capacity and cost effectiveness.

Revisiting the Oxidation of Graphite: Reaction Mechanism, Chemical Stability, and Structure Self-Regulation.

To fully understand the chemical structure of graphene oxide and the oxidation chemistry of sp2 carbon sites, we conducted a practical experiment and density functional theory combined study on the oxidation process of graphite. The nuclear magnetic resonance, thermogravimetric analysis, and X-ray photoelectron spectroscopy results of unhydrolyzed oxidized graphite indicate that the oxidation process involves the intercalating oxidation, where electrically neutral species is the oxidizing agent, and the diffusive-oxidation, where MnO3+ is the oxidizing agent. An intrinsic formation and conversion path of oxygen-containing functional groups is proposed based on the experimental results and further interpreted with the aid of frontier molecular orbital theory and density functional theory. Meanwhile, the two unique features of the oxidation process of graphite, the chemistry stability of oxygen-containing functional groups in the strong oxidizing medium, and the self-regulation of the oxidation process are theoretically reasoned.

CeO2 nano-hexagons decorated rGO/CNT heterostructure for high-performance LPG sensing

This paper reports, the improved sensitivity and selectivity of liquefied petroleum gas (LPG) sensing at room temperature based on ternary heterostructure nanocomposite (CeO2–rGO/CNT). Detection of LPG is required for proper environment monitoring to avoid any health hazards in the household and industrial areas. Towards this, a low-cost, high performance, and high stable room temperature gas sensor was fabricated. CeO2 nanopuzzles was synthesized by Eggshell membrane template assisted hydrothermal method and nanocomposites by sono-chemical route. As-synthesized materials and nanocomposites were analyzed by employing characterizations like XRD, Raman, FT-IR, FESEM, and TEM, which confirmed the formation of shape, size, structure, and functional groups involved. The current study focuses on the fabrication of room temperature LPG sensor based on hybrid nanocomposites coated on flexible polyethylene terephthalate substrate working electrodes for In-house chemiresistive LPG detection unit to study response, stability, and selectivity parameters. The ternary heterostructure nanocomposite gas sensor exhibited good selectivity to LPG at room temperature. This sensor showed the response of 42% at 400 ppm of LPG, which is 2.21 times than pure CeO2 sensor with a short response time 26 s and recovery time of 98 s, and gained 99% response after bending with 95.2% stability and 85.7% periodic stability of the sensor.

Atmospheric air plasma jet for improvement of paint adhesion to aluminium surface in industrial applications

Improvement of paint adhesion to aluminium surfaces is one of the main challenges in many industrial applications. In this paper, we introduce the atmospheric pressure air plasma jet as an appropriate candidate for preparation of 5052 aluminium surface alloy to improve paint adhesion in the industrial level. The employed plasma jet can promote paint adhesion to aluminium surface at the treatment velocity of 2 m/min and plasma size of 10 mm. Based on the cross-cut test, adhesion of polyurethane paint to the surface greatly increases from 1B to 5B level due to the plasma treatment. According to the results, the surface wettability increases under the influence of the plasma treatment so that water droplet contact angle reduces from 79.0°±2.0°–27.5°±2.0° after the treatment. Dyne test ink also denotes the increment of surface energy to the greater than 72 mN/m. Besides, we employ various analytical methods to investigate the physical and chemical changes arise from the plasma processing to the surface. Atomic force microscopy (AFM) results show a twofold increase in the roughness parameters of plasma treated surface which can result in a stronger paint and surface interlocking. Chemical analysis of the surface reveals that plasma treatment of the aluminium surface leads to the surface cleaning and formation of hydrophilic functional groups that attract much more water towards the surface and improves the paint adhesion.

Electrical Properties of Newly Calcified Tissues on the Surface of Silver Ion Administrated Hydroxyapatite Scaffolds

The application of electric field to graft materials has significant contribution in bone healing mechanism. Hence, the aim of this study is to develop conductive hydroxyapatite (HAp) scaffolds by introducing different concentrations of silver ion into its structure and demonstrate its impact on in vitro bioactivity and electrical properties. Hydroxyapatite was synthesized by wet chemical method and calcium ions from HAp structure have been partially replaced by silver ions. The HAp and Ag-HAp nanocomposites were characterized by Fourier-transform infrared, Raman spectroscopy, XRD and EDAX for functional group and phase formation analysis as well as to confirm existence of silver ions in HAp structure respectively. Bioactivity of these scaffolds was assessed by using simulated body fluid. The surface morphology, structural analysis and electrical properties of scaffolds before and after formation of newly calcified tissues on its surface were examined via scanning electron microscopy (SEM), XRD, FTIR, dielectric and impedance spectroscopy techniques. Overall, our finding suggests that the administration of silver ions in HAp scaffold boosts bioactivity and has strong correlation with electrical properties.

Enhanced adsorption of aqueous acetone by modified powdered activated carbon

ABSTRACT Acetone, a small molecule organic compound, is freely soluble and volatile. To improve the removal rate of acetone, three different types of powdered activated carbon (PAC) were compared and then modified with formic acid and NaOH to optimize the adsorption capacities of PAC. The adsorption mechanism and the effect of physical–chemical properties of PAC to the adsorption were clarified. Results show that PAC produced from wood performed best adsorption capacities. The pseudo-second-order model and the Freundlich model accurately described the adsorption behaviour, while lower temperature was more conducive to the adsorption process. PAC giving a higher acetone adsorption capacity had a larger specific surface area, a richer micropore structure, a larger micropore volume, a smoother surface, with more acidic, oxidizing functional groups. The adsorption removal efficiency of modified PACs with formic acid was improved from 60.89% to 82.93%, while NaOH modification decreased the adsorption capacity. The positive effect of formic acid was attributed to the formation of novel acidic oxygen-containing functional groups, which was supported from the NaOH treatment that removed original acidic oxygen-containing functional groups, contrarily the formation of novel alkaline reducing functional groups did not restore the acetone adsorption capacity. We conclude that wooden PAC is a suitable adsorbent for acetone, in particular after pretreatment with formic acid.

Effect of Acid Treatment on the Functionalization of Surface, Structural and Textural Properties of Carbon Nanotubes Taunit

The role of acid treatment of Taunit carbon nanotubes in the formation of oxygen-containing functional groups on its surface as well as morphological and textural properties was studied. Acid treatment was carried out in an HNO3 solution or its mixture with H2SO4 under mild conditions (85 °C/1 h) with subsequent washing with distilled water or without washing. Properties of the initial and oxidized samples were investigated using elemental carbon, hydrogen, nitrogen, oxygen (CHNO) analysis, BET (Brunauer-Emmett-Teller) determination of surface area, X-ray diffraction, Raman and Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy, and hydrogen temperature-programmed reduction. Treatment with HNO3 and HNO3/H2SO4 mixture was shown to be efficient for the formation of various oxygen-containing groups on the Taunit surface; therewith, the water washing step also contributed to functionalization of the surface. Depending on the oxidant, acid treatment increased graphite and oxygen content in the samples by a factor of 3‒4.5. Treatment with HNO3 without water washing exerted a weak effect on the graphite structure ordering, the concentration of aliphatic groups was high as compared to other oxidation conditions. Treatment of Taunit with the HNO3/H2SO4 mixture, on the contrary, increased the number of defects in graphite layers and decreased the concentration of aliphatic structures.

Investigation on the effect of transition metal chloride on anthracite combustion

In recent years, the international community has paid more attention to environmental pollution and climate change caused by the use of fossil fuels. How to strengthen the efficient use of coal has become a problem that must be solved. This work aims to study the effect of transition metal chlorides (CuCl2, FeCl3 and ZnCl2) on the promotion of “burn off” reaction and the improvement of anthracite heat release efficiency by using TG-DSC, FTIR and EPR. The effect of adding three transition metal chlorides on oxygen absorption and heat release of anthracite was studied by TG-DSC. Results show that the addition of CuCl2, FeCl3 and ZnCl2 can promote the “burn off” reaction, thereby increasing the heat release efficiency of anthracite. Specifically, the addition of CuCl2 increases the heat release of the anthracite by 15%. FTIR was used to study the structural changes during the heating process of raw coal and coal with transition metal chlorides. Results show that CuCl2 can effectively promote the direct pyrolysis of aliphatic functional groups and reduce the formation of oxygen-containing functional groups. In addition, the mechanism of CuCl2 promoting the “burn off” reaction was studied by ESR spectra analyses. It is found that the free radical concentration of the coal with CuCl2 is higher than that of the raw coal, which indicating that the “burn off” reaction is an oxidation reaction dominated by free radical. This work may have a guiding significance for the efficient utilization of anthracite.

Direct functionalizing of acrylonitrile-butadiene rubber surfaces through different peroxide curing

This study focuses on the influence of peroxide type on the chemical composition, curing properties, and free-radical reactions of peroxide cured acrylonitrile-butadiene rubber (NBR). A novel perspective regarding peroxide curing as a surface modification method to control the formation of functional groups on cured rubber surfaces via the primary curing process is provided. During curing, the peroxide acts as a useful curing agent and as an efficient controller of functional group formation on rubber surfaces. Surface functionalization of NBR cured using peroxides containing structures such as alkyl, phenyl, and both groups was examined by X-ray photoelectron spectroscopy (XPS). The effects of different curing temperatures were also studied. Oxygen-containing functional groups were obtained on the cured NBR surfaces. Notably, NBR surfaces cured by the peroxide containing phenyl groups showed an increased abundance of oxygen-containing functional groups compared to those cured by the peroxide containing alkyl groups. The functional group formation mechanism on rubber surfaces is also discussed herein. This strategy offers opportunities for large-scale fabrication of versatile functional surfaces and thin films on rubber for various applications.

Environmental behavior of engineered biochars and their aging processes in soil

In recent years, due to the broad application of biochars, the preparation, environmental behavior and aging processes of biochars have attracted wide attention globally, especially the modification of biochars. However, most of the studies only consider the improvement of biochar properties right after the modification, but neglect a complete evaluation of the long-term stability and eco-toxicity of these newly developed materials after entering the environment. With the development and utilization of biochars, engineered biochars (EngBCs) will soon enter the market, but its environmental risk still remains unclear. The literature does not provide adequate information on how aging of EngBCs will affect their properties, and indirectly impact the properties of soils (cycle of elements and organic matter). Therefore, this review paper summarizes the aging process and environmental risk of biochars, aiming at better understanding the interactions between EngBCs and soil components or pollutants. More importantly, this review is to point out the contradictory speculations of environmental behavior of EngBCs studied at the present stage. Due to the modification, the EngBCs stability may be significantly reduced. However, the formation of functional group on EngBCs will enhance their interaction with soil minerals to form biochars–mineral complex, and thus EngBCs could be protected. The impacts of EngBCs after entering the environment are also ambiguous. Therefore, understanding EngBCs environmental behavior is critical, which is helpful to reduce the potential risk and to produce EngBCs following the rule of sustainable development and safety to the environment.

Fabrication and Photodegradation Application of Isopropanol-Functionalized Poly (Triazine Imide)

This study reported the fabrication and photodegradation application of surface-functionalized poly (triazine imide) (PTI). PTI was obtained through a single-step thermal decomposition process, followed by mild isopropanol (IPA) oxidation treatments at various temperatures. The PTI structure was retained after the surface functionalization; however, the crystallinity deteriorated. The IPA-treated samples exhibited carbon-to-nitrogen ratios similar to those exhibited by pristine PTI. Furthermore, they displayed the morphology of tetragonal tubes and layered nanosheets. Triazine units were confirmed by conducting Fourier transform infrared spectroscopy. The analyses of 13C cross-polarization magic angle spinning solid-state nuclear magnetic resonance and x-ray photoelectron spectroscopy validated the formation of functional groups of C=O and –COOH or –COOR on the PTI surface. After IPA oxidation at 120°C (IPA-120), the sample exhibited reliable photodegradation of methylene blue with a degradation rate constant (k) of approximately 0.01 min−1, which was almost 2.5 times higher than that of pristine PTI. Our study revealed that a low recombination of photogenerated electron–hole pairs was crucial to induce synergistic photocatalysis; however, the sample also exhibited a high specific surface area, enhanced visible light absorption, and a reduced band gap (approximately 2.3 eV). Furthermore, the constructed energy band diagram supported the observations in the photodegradation and scavenger studies.