Degradation Efficiency Of Pollutants Research Articles

Boron functionalized carbon-based metal-free catalyst for efficient photoelectrocatalytic degradation of pollutants

Boron functionalized carbon-based metal-free catalyst for efficient photoelectrocatalytic degradation of pollutants

Advanced oxidation processes (AOPs): Navigating from MOS to COS and X-COS systems - Unraveling strategies, tackling challenges, and pioneering advances

This article presents a significant advancement in the field of photocatalysis through the synthesis of a MSO(Metal oxide semiconductor), COS (coupled oxide semiconductor) and X-COS(doped coupled oxide semiconductor) nanocomposite systems with diverse morphologies, including nanoflowers, nanorods, nanosheets, nanotubes and spherical shapes. In this particular study, we propose a hybrid methodology that amalgamates the coupling of CuO and ZnO oxides and the doping of various elements resulting in a comprehensive study of the relationship between morphology and photocatalysis. The degradation efficiency for various pollutants, including Methylene Blue (MB), Methyl Orange (MO), Green Malachite (GM), and Rhodamine B (RhB), was systematically investigated, employing distinct degradation mechanisms. Our study reveals that X-COS materials exhibit superior surface area, heightened porosity, and elevated specific capacitance, higher light absorption while minimizing energy and surface losses (VELF and SELF), accompanied by a well-suited morphology. These distinctive structural features of X-COS contribute to its enhanced photocatalytic efficiency when compared to MOS and COS systems. Our research not only consolidates the fundamental principles governing the photocatalytic properties of materials but also unveils critical strategies for fabricating highly efficient catalysts. In conclusion, this work significantly contributes to the evolving landscape of photocatalysis, offering a nuanced understanding of the synergistic relationship between morphology and catalytic efficiency. The findings not only broaden the scope of fundamental principles but also pave the way for the development of highly effective catalytic materials with diverse morphologies for environmental remediation applications.

Biocatalytic Functionalities of Lignin Peroxidase-Based Systems in Lignin Depolymerization and Pollutants Removal from Environmental Matrices

Abstract Purpose of Review In the presented review, we have summarized and highlighted recent developments in the use of lignin peroxidase (LiP) to remove a variety of pollutants from water matrices. The high redox potential of LiP is underlined by its excellent catalytic functionalities in the elimination of pharmaceuticals, phenolics, dyes, polycyclic aromatic hydrocarbons (PAHs), endocrine-disrupting chemicals (EDCs), and other miscellaneous pollutants. LiP-based computational frameworks for theoretical bioremediation of multiple pollutants have also been discussed, which have prompted a rise in scientific interest. Recent Findings According to current studies, both free and immobilized LiPs are biocatalysts capable of efficient pollutant degradation and LMW transformation. Some immobilized LiP preparations demonstrated excellent recyclability, enabling its reusability in multiple catalytic cycles. Additionally, computational degradability makes it easier to comprehend the mechanisms underlying the degradation of recalcitrant pollutants. Summary The capacity of LiP to cleave C–C and C–O–C bonds has led to its widespread application as a biocatalyst. Its outstanding potential to catalyze oxidative cleavage has been effectively used in the remediation of pollutants without needing mediators. Nevertheless, we brought attention to the current LiP system in pollutants remediation and computational framework, which has generated a significant rise in scientific interest.

Expansion-flow-modulated 3D printing of vertically aligned graphene photofuel cell

Channel-aligned regulation of photoelectrode within the bulk structure to generate eminent light absorbance and high-level pollutant adsorption is pivotal but challenging for realizing high-performance photofuel cell (PFC) system. Herein, we demonstrated an effective and scalable expansion-flow-modulated direct ink writing (DIW) 3D printing strategy for controllably constructing microlattice photoelectrode, with multiscale well-interconnected oriented channels built by layer-by-layer highly-regular assembly of filaments and vertical alignment of graphene nanosheets within filaments as well as uniform coupling of abundant photoactive nanoparticles to highly ordered channel walls. The unique architectural features enabled high-speed and effective diffusion/trapping of wastewater pollutants throughout the entire photoelectrode, and meanwhile facilitated ready spreading of incident light into the photoelectrode interior to yield high light absorption. As a result, an integrated 3D-printed vertically-aligned PFC (3DP VAPFC) assembled with as-fabricated photoelectrode exhibited its powerful capability for efficiently converting wastewater pollutants into electric energy under sunlight, with remarkable cycling stability and maximum power density of 0.11 mW cm−2. This work opens a promising route for architecting advanced photoelectrode toward PFC devices with highly efficient degradation and electricity generation of pollutants.

Controlled synthesis of CoFe@TiN composites and their rapid and efficient degradation of emerging organic pollutants: RhB as an example

Fast removal of emerging organic pollutants (EOPs) is very important for the remediation of the water environment. Therefore, in this study, we used a simple grinding-calcined assembly method to prepare CoFe@TiN metallic composite, which possessed superb peroxy disulfate (PDS) activation ability with efficient pollutant degradation and excellent cyclic utilization. Rhodamine B, a highly representative and extensively used EOP, was adopted as a model pollutant, showing that it was completely degraded within only 9min by the CoFe@TiN/PDS. During the degradation, superoxide radical (O2•−) were the main active oxygen species responsible for pollutant degradation. Further analysis showed that the synergistic effect of Fe(III)/Co(II) effectively activated the PDS to degrade the pollutant. In practical applications, the CoFe@TiN/PDS system can resist the influence of complex matrix in water and effectively remove EOPs in real water bodies. This study comprehensively evaluates the ability of the CoFe@TiN/PDS system to remove EOPs and thus provides a new scenario or pathway for the removal of EOPs in real contaminated water bodies.

Photo-assisted Natural Chalcopyrite Activated Peracetic Acid for Efficient Micropollutant Degradation

The effective activation of natural chalcopyrite (CuFeS2) on peracetic acid (PAA) to remove organic micropollutants was studied under visible light irradiation. Results showed than an effective sulfamethoxazole (SMX) degradation (95.0%) was achieved under visible light irradiation for 30 min at pH 7.0. Quenching experiments, electron spin resonance analysis, and LC/MS spectrum demonstrated that HO• and CH3C(O)OO• were the main reactive species for SMX degradation, accounting for 43.3% and 56.7% of the contributions, respectively. Combined with X-ray photoelectron spectroscopy analysis, the photoelectrons generated on CuFeS2 activated by visible light enhanced the Fe3+/Fe2+ and Cu2+/Cu+ cycles on the surface, thereby activating PAA to generate HO•/CH3C(O)OO•. The removal rate of SMX decreased with the increase in wavelengths, due to the formation of low energy photons at longer wavelengths. Besides, the optimal pH for degradation of SMX by CuFeS2/PAA/Vis-LED process was neutral, which was attributed to the increasing easily activated anionic form of PAA during the increase in pH and the depletion of Fe species at alkaline conditions. Cl−, HCO3−, and HA slightly inhibited SMX degradation because of reactive species being quenched and/or shielding effect. Furthermore, the degradation efficiency of different pollutants by CuFeS2/PAA/Vis-LED was also measured, and the removal efficiency was different owing to the selectivity of CH3C(O)OO•. Finally, the process exhibited good applicability in real waters. Overall, this study provides new insight into visible light-catalyzed activation of PAA and suggests on further exploration of the intrinsic activation mechanism of PAA.

Construction of a direct Z-scheme Cs3Bi2Cl9/g-C3N4 heterojunction composite for efficient photocatalytic degradation of various pollutants in water: Performance, kinetics and degradation mechanism

The use of emerging composite materials has been booming to remove environmental pollutants. The aim of this research is to develop a new composite based on Cs3Bi2Cl9 perovskite and graphitic carbon nitride (g-C3N4) to investigate the photocatalytic performance under visible light irradiation. To achieve this, we produce the Cs3Bi2Cl9/g-C3N4 heterojunctions through a simple self-assembly synthesis. The as-synthesized composites are characterized using XRD, FTIR, FESEM, TEM, BET and EDX techniques. The photocatalytic performance of Cs3Bi2Cl9/g-C3N4 is examined in the degradation of various water contaminants, including 4-nitrophenol (4-NP), tetracycline antibiotic (TC), methylene blue (MB) and methyl orange (MO). The experimental results indicate the superior photocatalytic performance of the composites in the degradation of pollutants compared to pure Cs3Bi2Cl9 and g-C3N4. The 10% Cs3Bi2Cl9/g-C3N4 composite achieves the optimal degradation efficiency of 100, 92, 98.7, and 85.1% of 4-NP, TC, MB, and MO, respectively. This superior photocatalytic activity attributes to improved optical and electrochemical properties, including enhanced absorption ability, narrowing band gap, promoted separation efficiency of photogenerated carriers, and a high redox potential, which is confirmed by UV–vis DRS, PL, EIS, and CV analyses. The 10% Cs3Bi2Cl9/g-C3N4 composite also demonstrates high photocatalytic stability after four consecutive cycles. Radical trapping tests show that superoxide radicals (•O2−), holes (h+), and hydroxyl radicals (•OH) contribute to the photocatalytic process. Based on the obtained data, a direct Z-scheme heterojunction mechanism is proposed. Overall, this research offers a new stable photocatalyst with excellent prospect for photocatalytic applications.

Methyl contributes to the directed phosphorus doping of g-C3N4: pH-dependent selective reactive oxygen species enable customized degradation of organic pollutants

In the photocatalytic degradation process, constructing a controllable composite oxidation system with radicals and nonradicals to meet the requirement for efficient and selective degradation of diverse pollutants is significant. Herein, a methylated and phosphorus-doped g-C3N4 (NPEA) can exhibit selective radical and nonradical species formation depending on the pH values. The NPEA can spontaneously switch the production of active species according to the pH value of the reaction system, exhibiting steady-state concentrations of ·O2− for 11.83 × 10−2 µmol L−1 s−1 (with 92.7 % selectivity) under alkaline conditions (pH = 11), and steady-state concentrations of 1O2 for 5.18 × 10−2 µmol L−1 s−1 (with 88.7 % selectivity) under acidic conditions (pH = 3). The NPEA exhibits stability and universality in the degradation of pollutants with rate constant for sulfamethazine (k = 0.261 min−1) and atrazine (k = 0.222 min−1). Moreover, the LC-MS and Fukui function demonstrated that the NPEA can tailor degradation pathways for pollutants, achieving selective degradation. This study offers a comprehensive insight into the mechanism of the photocatalytic oxidation system, elucidating the intricate interplay between pollutants and reactive oxygen species.

Highly efficient activation of peroxymonosulfate by calcinated construction & demolition waste powder with free radical generation for organic pollutant degradation

BackgroundA simple, efficient and cost-efficiency peroxymonosulfate (PMS) oxidation process for organic pollutant removal is expected. This research aims to investigate the feasibility of construction & demolition waste (C&D waste) as recycled material for organic pollutant degradation. MethodsC&D waste was novelty introduced into the advanced oxidation process for organic pollutant removal. Taking phenol as the target pollutant, the effects of C&D waste loading, PMS concentration, particle diameter and solution pH were all investigated in this study by a series of batch tests and spectrometry measurements. Significant findingsBoth the intrinsic oxidation power of PMS and the adsorption of the pretreated C&D waste were negligible under this CDW/PMS system. However, calcinated C&D waste, with calcium silicate generation, enhanced the degradation efficiency of target organic pollutant by promoting the decomposition of PMS to generate •OH and SO4•−. Both •OH and SO4•− had been detected through the free radicals quenching tests and electron paramagnetic resonance (EPR) spectrometry. Except for high temperature pretreatment, the micro C&D waste after mechanical treatment could also improve the organic pollutant degradation efficiency with a high kinetic rate as a bonus especially for the introduced powder at low doses.

Biotechnological Breakthroughs: Paving the Path to Cleaner and More Productive Agriculture through Bioremediation

In recent years, biotechnological advancements have played a pivotal role in transforming traditional agricultural practices into sustainable and environmentally conscious systems. This article explores the revolutionary concept of bioremediation and its potential to address soil pollution, enhance crop productivity, and mitigate the environmental impact of conventional farming methods. Bioremediation involves harnessing the power of microorganisms, plants, or enzymes to detoxify or remove pollutants from soil, presenting a promising solution to the challenges posed by agrochemicals and industrial wastes. The first section of this abstract delves into the current state of agriculture, highlighting the widespread use of chemical fertilizers, pesticides, and herbicides, which has led to soil degradation, water contamination, and loss of biodiversity. These issues necessitate a paradigm shift towards sustainable agricultural practices that prioritize soil health and ecosystem balance. The second section explores the fundamental principles of bioremediation, emphasizing its versatility in addressing a wide range of pollutants, including heavy metals, pesticides, and organic contaminants. Through the use of genetically engineered microorganisms or naturally occurring plant-microbe partnerships, bioremediation offers a targeted and eco-friendly approach to soil restoration. Moving forward, the paper examines specific biotechnological breakthroughs that have propelled the field of bioremediation. From the development of genetically modified crops with enhanced phytoremediation capabilities to the use of engineered microbes for efficient pollutant degradation, these innovations showcase the potential of biotechnology in revolutionizing agriculture. Furthermore, the paper explores the economic and environmental benefits associated with the adoption of bioremediation techniques in agriculture. By reducing the reliance on synthetic chemicals, farmers can lower production costs, while simultaneously preserving soil fertility and safeguarding water resources. The potential for increased crop yields and improved food quality further underscores the positive impact of bioremediation on agricultural productivity.

Complexation between butyl xanthate and Cu enhanced peroxydisulfate activation and cation redox cycle by Fe-Cu-LDH/biochar

Butyl xanthate (BX) is one of the most widely used collector in sulfide flotation. It is harmful to human health but its degradability has not been addressed in depth. In this study, Fe-Cu-Layered double hydroxides/Biochar composites (Fe-Cu-LDH/BC) were prepared and firstly used to activate peroxydisulfate (PDS) for degradation of butyl xanthate. More than 90 % of BX could be completely degraded within 10 min under conditions of 20 mg/L BX, 0.2 g/L LDH/BC and 0.1 mM PDS. The high degradation efficiency was owing to the complex formation between catalyst and contaminant molecule by a coordination bond of the Cu in Fe-Cu-LDH/BC and the S in BX. Through DFT calculations, it could be found that this complexation enhanced the adsorption efficiency of LDH/BC on PDS and the reactivity of the Cu site. EPR was applied to analyze the reactive substances in the reaction, and various reactive oxygen species such as O2•−, •OH and SO4•− were detected in the process. In addition, LC-MS was used to analyze and speculate the intermediates and degradation pathways of BX. In conclusion, this material can promote the degradation of BX in water under different conditions and has great potential in treating mine wastewater. Meanwhile, this study proposes new ideas for the synthesis of new catalysts for the efficient degradation of pollutants.

Discriminating the Active Ru Species Towards the Selective Generation of Singlet Oxygen from Peroxymonosulfate: Nanoparticles Surpass Single-Atom Catalysts.

Singlet oxygen (1 O2 ) is an exceptional reactive oxygen species in advanced oxidation processes for environmental remediation. Despite single-atom catalysts (SACs) representing the promising candidate for the selective generation of 1 O2 from peroxymonosulfate (PMS), the necessity to meticulously regulate the coordination environment of metal centers poses a significant challenge in the precisely-controlled synthetic method. Another dilemma to SACs is their high surface free energy, which results in an inherent tendency for the surface migration and aggregation of metal atoms. We here for the first time reported that Ru nanoparticles (NPs) synthesized by the facile pyrolysis method behave as robust Fenton-like catalysts, outperforming Ru SACs, towards efficient activation of PMS to produce 1 O2 with nearly 100 % selectivity, remarkably improving the degradation efficiency for target pollutants. Density functional theory calculations have unveiled that the boosted PMS activation can be attributed to two aspects: (i) enhanced adsorption of PMS molecules onto Ru NPs, and (ii) decreased energy barriers by offering adjacent sites for promoted dimerization of *O intermediates into adsorbed 1 O2 . This study deepens the current understanding of PMS chemistry, and sheds light on the design and optimization of Fenton-like catalysts.

Discriminating the Active Ru Species Towards the Selective Generation of Singlet Oxygen from Peroxymonosulfate: Nanoparticles Surpass Single‐Atom Catalysts

AbstractSinglet oxygen (1O2) is an exceptional reactive oxygen species in advanced oxidation processes for environmental remediation. Despite single‐atom catalysts (SACs) representing the promising candidate for the selective generation of 1O2 from peroxymonosulfate (PMS), the necessity to meticulously regulate the coordination environment of metal centers poses a significant challenge in the precisely‐controlled synthetic method. Another dilemma to SACs is their high surface free energy, which results in an inherent tendency for the surface migration and aggregation of metal atoms. We here for the first time reported that Ru nanoparticles (NPs) synthesized by the facile pyrolysis method behave as robust Fenton‐like catalysts, outperforming Ru SACs, towards efficient activation of PMS to produce 1O2 with nearly 100 % selectivity, remarkably improving the degradation efficiency for target pollutants. Density functional theory calculations have unveiled that the boosted PMS activation can be attributed to two aspects: (i) enhanced adsorption of PMS molecules onto Ru NPs, and (ii) decreased energy barriers by offering adjacent sites for promoted dimerization of *O intermediates into adsorbed 1O2. This study deepens the current understanding of PMS chemistry, and sheds light on the design and optimization of Fenton‐like catalysts.

Switching reactive oxygen species reactions derived from Mn–Pt anchored zeolite for selective catalytic ozonation

Rationally switching reactive oxygen species (ROS) reactions in advanced oxidation processes (AOPs) is urgently needed to improve the adaptability and efficiency for the engineering application. Herein we synthesized bimetallic Mn–Pt catalysts based on zeolite to realize the switching of ROS reactions in catalytic ozonation for sustainable degradation of organic pollutants from water. The ROS reactions switched from singlet oxygen (1O2, 71.01%) to radical-dominated (93.79%) pathway by simply introducing defects and changing Pt/Mn ratios. The oxygen vacancy induced by anchoring Mn–Pt species from zeolite external surface (MnPt/H-Beta) to internal framework (MnPt@Si-Beta) exposes more electron-rich Pt2+/Pt4+ redox sites, accelerating the decomposition of O3 to generate •OH via electron transfer and switching ROS reactions. The Mn site acted as a bridge plays a critical role in conducting electrons from organic pollutants to Pt sites, which solidly solves the electron loss of catalysts, facilitating the efficient degradation of pollutants. A 34.7-fold increase in phenol degradation compared with the non-catalytic ozonation and an excellent catalytic stability are achieved by MnPt@Si-Beta/O3. The 1O2-dominated ROS reaction originated from MnPt/H-Beta/O3 exhibits superior performances in anti-interference for Cl−, HCO3−, NO3−, and SO4−. This work establishes a novel strategy for switching ROS reactions to expand the targeted applications of O3 based AOPs for environmental remediation.

Insight into the activation of periodate by Mn(II) for rapid degradation of sulfadiazine: Performance and mechanisms

The present study investigated the mechanism of manganese ion (Mn(II))-activated periodate (PI) for rapid removal of sulfadiazine (SDZ). The Mn(II)/PI system showed excellent SDZ degradation results with 99.8 % degradation efficiency within 2 min at pH = 5.5. Mechanism study reveals that the degradation of SDZ in the Mn(II)/PI system takes place mainly through an electron transfer process. Mn(II) can be oxidized by PI to formed the in-situ MnO2, followed by the generation of MnO2-PI complex. Electrochemical methods have confirmed that the generated MnO2-PI complex significantly contributes to the degradation of pollutants. MnO2-PI mediates the transfer of electrons from SDZ to PI surface through surface vacancies, thereby achieving efficient degradation of pollutants. p-methoxyphenyl sulfone (PMSO) is used as a probe compound, and almost 90 % of PMSO is converted into PMSO2 in the Mn(II)/PI/SDZ system, manifesting that excessive PI may oxidize active Mn(IV) to Mn(V). And the generated Mn(V) also contributes to the SDZ degradation. The SDZ degradation pathway is proposed and the transformation of iodine species is detected. The final iodine species in the system are iodate. The chloride culture experiment has confirmed that the production of organic iodine is very low, indicating no significant health risks. This study reveals mechanism of periodate-based process, providing theoretical and technical implementation guidelines of periodate in water treatment.

Enhanced advanced oxidation treatment through the synergy of chloride ion activation and electro-Fenton process

A photoelectrocatalytic system has been developed utilizing the WO3@BiVO4 photoanode and the oxidized carbon black (CB) cathode, enabling the synergistic advanced oxidation treatment by combining chlorine radicals and hydroxyl radicals. The WO3@BiVO4 heterojunction is prepared through hydrothermal growth of BiVO4 onto the surface of WO3 synaptic structure. The as-prepared WO3@BiVO4|Pt system demonstrates a remarkable degradation efficiency of organic pollutants with 97.1 % in 30 min under visible light irradiation with a 1.2 V bias, which is 1.24 times higher compared to the WO3|Pt system. Furthermore, even when utilizing actual seawater as the electrolyte, the treatment efficacy remains high at 92.8 % within 20 min. The oxidized CB cathode is obtained by calcining commercial CB in the air atmosphere. The WO3@BiVO4|CB system achieves the degradation efficiency of 85.9 % within 10 min in simulated seawater, utilizing the electro-Fenton process at 0.2 V. The WO3@BiVO4|CB system effectively removes organic pollutants through the synergistic effect of combining the WO3@BiVO4 photoanode with CB-A cathode. Additionally, impressive degradation efficiency of 97.8 % is achieved in 15 min when using simulated seawater as the electrolyte. The •OH, •Cl, and •Cl2− play the key role in the WB|CB-A synergistic system. The combined action of anodic active chlorine radicals and cathodic electro-Fenton process in the WO3@BiVO4|CB system demonstrates effective microorganism sterilization, resulting in a 92.5 % reduction within 15 min

Fabrication of MXene-derived TiO2/Ti3C2 integrated with a ZnS heterostructure and their synergistic effect on the enhanced photocatalytic degradation of tetracycline

Developing innovative photocatalysts for the efficient degradation of pharmaceutical pollutants is crucial in environmental remediation. In this study, we investigate the synthesis of TiO2 nanosheets derived from MXene, specifically integrated onto highly conductive Ti3C2 MXene, and subsequently combined with zinc sulfide (ZnS) to form a heterojunction. This integration process is accomplished using a hydrothermal approach followed by a self-assembly method. We aim to assess the effectiveness of this integrated system in enhancing the photocatalytic degradation of tetracycline (TC). TiO2/Ti3C2 (TT) synthesized in situ exhibits high-energy lattice facets (001) of TiO2 nanosheets, thereby contributing to an exclusive heterojunction within the TiO2/Ti3C2/ZnS (ZTT) heterostructure. The loading of ZnS nanoparticles significantly increases the surface area with a narrow band gap, enhancing the potential for light emission within the visible region. Consequently, ZnS synergistically affects the ZTTx (where x = wt% of ZnS on TT) heterostructure matrix, notably promoting the separation and transfer abilities of the photogenerated carriers. The ZTT5 heterostructure exhibits remarkable adsorption and photoreduction efficiencies, achieving a 97.1% TC removal in 60 min under UV light. Moreover, under simulated solar light, the ZTT5 heterostructure exhibits an impressive TC removal rate of ∼93.8% in 90 min. These results highlight the effective performance of the ZTT5 heterojunction catalyst in facilitating photogenerated charge carriers, leading to improved photocatalytic capabilities. Furthermore, the band structure and density of states of TiO2 (101), Ti3C2 (002), and ZnS (111) were investigated using density functional theory. In addition, a photoreduction mechanism was proposed for TC, involving the transfer of electrons from TiO2 to the MXene surface. After the transfer, the electrons react with O2 to generate •O2−, attributed to the high electron mobility of MXene. The results of this study emphasize the significant potential of the ZTT5 heterostructure for efficiently degrading pharmaceutical pollutants from wastewater.

Directional charge transfer modulation in ultrathin polyporous carbon nitride nanotubes for enhanced peroxymonosulfate activation

Achieving enhanced degradation efficiency of the legacy pesticidal persistent organic pollutants in a photocatalysis coupling peroxymonosulfate activation (PC-PMS) system by boosting photogenerated carrier separation, remains considerable challenges. Herein, we delved into the directional charge transfer modulation of built-in electric field (BEF) within polyporous ultrathin carbon nitride nanotubes for strengthened PC-PMS mediated pesticide degradation. The ultrathin polyporous tubular nanostructure, are critical in shortening the diffusion pathways for the transport of photogenerated electron-hole pairs to the reaction interface, while simultaneously ensuring the abundant contact sites for the reaction medium. Additionally, the heptazine units containing amino groups served as oxidation centers under visible light, targeting the generation of reactive oxygen species of h+, O2•−, 1O2. While the heptazine units containing cyano groups and boron dopants acted as reduction centers, activating PMS and O2 to produce SO4•−, •OH and O2•−. The efficient generation of the radical species contributed to the ultrafast imidacloprid degradation in PC-PMS system. This study demonstrates that the combination of morphology and BEF engineering is a promising strategy for enhanced degradation efficiency of pesticide pollutants in the PC-PMS system.

Highly Effective Fe-Doped Nano Titanium Oxide for Removal of Acetamiprid and Atrazine under Simulated Sunlight Irradiation

Pesticides are widely detected in large quantities in the environment, posing an ecological threat to the human body and ecology. Semiconductor nanomaterials such as nano-titania (nTiO2) have strong photocatalytic degradation efficiency for pollutants. However, the wide bandgap and limited light absorption range inhibit nano-titania’s practical application. Therefore, nTiO2 was modified by Fe3+ doping using the microwave hydrothermal method to improve its photocatalytic performance in this study. Fe-nTiO2 doped with a 1.0% mass ratio was used due to its high photocatalytic performance. Its maximum degradation efficiencies for ACE and ATZ under a 20 W xenon lamp were 88% and 88.5%, respectively. It was found that Fe3+ doping modification distorted the spatial morphology of nTiO2 and shortened the bandgap to facilitate the photocatalytic reaction. The electron paramagnetic resonance results showed that the reactive radicals (1O2, ·OH) produced by photogenerated electrons (e−) and holes (h+) of Fe-nTiO2 were the main active species in the degradation of ACE and ATZ. Additionally, the application of Fe-nTiO2 significantly enhanced the growth of lettuce under sunlight; the degradation efficiencies of ACE and ATZ in lettuce were 98.5% and 100%, respectively. This work provides new insights into the removal of organic contaminants by photocatalysts under sunlight in agriculture.

Efficient activation of peroxymonosulfate for trichloroethylene degradation by cobalt ferrites anchored on CeO2 surfaces: Radical to non-radical pathway shift

This research investigates the unique configuration of cobalt ferrite (Co1.5Fe1.5O4) anchored onto the surface of cerium dioxide (CeO2), which effectively activates peroxymonosulfate (PMS) to degrade trichloroethylene (TCE). Co1.5Fe1.5O4-CeO2/PMS was able to completely degrade 5 mg/L of TCE by comparison between PMS and the components of the prepared composites. In addition, the Co1.5Fe1.5O4-CeO2/PMS system was highly adaptable to pH and aqueous substrates. Quenching experiments combined with ESR spectroscopy results demonstrated that ·OH, SO4·-, O2·-, and 1O2 in the system play an important role in degrading TCE. The Co1.5Fe1.5O4-CeO2/PMS system can maintain 90% degradation efficiency for various pollutants (TCE, carbon tetrachloride (CT), dichloromethane (DCM), 2,4-dichlorophenoxyacetic acid (2,4-D)) as well as the actual wastewater, and the multiple cycling experiments have verified that the Co1.5Fe1.5O4-CeO2/PMS has a good stability. XPS comparisons before and after the reaction revealed that cobalt ferrite exhibited a unique transition from the radical pathway to the non-radical pathway during TCE degradation after the introduction of CeO2. This pathway shift can be attributed to the synergistic interaction between cobalt ferrite and CeO2, which adjusts the electronic structure, facilitates the activation of PMS, and generates more reactive oxygen species to decompose TCE. This research offers valuable insights into the design of efficient advanced oxidation catalysts for the removal of organic pollutants from water and the optimization of degradation pathways.