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Highlights: [•] A Ca-montmorillonite was modified with DDTMA and HDTMA through direct ion exchange. [•] The prepared organoclays were characterized by XRD and BET instruments. [•] The adsorption conditions for BPA of organoclays were systematically studied. [•] The study provides a pathway for the removal of BPA from contaminated waters. [ABSTRACT FROM AUTHOR]

• The development and progression of NAFLD by common pollutants in water is reviewed. • Features in response to each environmental contaminant are elucidated. • The new perspective of joint toxicity of pollutants in water bodies is put forward. The global prevalence of nonalcoholic fatty liver disease (NAFLD) has been increasing rapidly in recent years, which is now estimated to be over 25%. NAFLD is one of the most common chronic liver diseases in the world. At present, with the rapid development of economy and industrialization, many chemicals are released into the environment. These chemical contaminants in the environment might cause harm to human health and result in lipid metabolism disorder during long-term exposure. Moreover, the incentive of many NAFLD cases is unknown, and the environmental risk factors of NAFLD need to be urgently identified. Hence, we focus on the impacts of several popular environmental contaminants in water environment on the development and progression of NAFLD. These contaminants mainly include microcystins (MCs), disinfection by-products (DBPs), heavy metals (HMs), dioxins and polychlorinated biphenyls (PCBs). Through analyzing a great many epidemiological and toxicological studies, we have found positive associations between NAFLD and chronic exposure to these contaminants at the environmental levels. This review may enhance the understanding of liver damage caused by environmental pollutants, which are considered as tangible environmental risk factors for NAFLD. [ABSTRACT FROM AUTHOR]

[Display omitted] • The synergistic effect of natural minerals for persulfate activation were reviewed. • The mechanism of persulfate activation and contaminants degradation were summarized. • We pointed out that the major challenges and direction of mineral-based catalysts. • This review is meaningful for the high-value-added application and functional specialization of minerals. The severity of environmental pollution poses a serious threat to human health, and especially organic pollution is more complex and difficult to treat compared to heavy metal pollution. Nowadays, the persulfate-based advanced oxidation processes receive more and more attention due to high efficiency, strong controllability, easy operation, and economic competitiveness, which is generally employed for the efficient degradation of organic contaminants. Natural minerals possess the characteristics of low-cost, easy availability, environmental friendliness, non-toxic, special structural effects, etc., which have played a critical role and could be the promising alternative to traditional catalysts for persulfate activation. First, this review retrospects the research status of natural minerals and mineral-based catalysts for persulfate activation to degrade organic contaminants, i.e., pyrite, mackinawite, copper sulfide, kaolinite, and montmorillonite. Then, the mechanisms of persulfate activation by natural minerals and mineral-based catalysts to generate the reactive oxygen species including SO 4 •−, •OH, •O 2 −, 1O 2 , and surface reactive complex for contaminants degradation are systematically summarized. Finally, we discussed the further application of natural minerals in activating persulfate as well as the future research frontiers for practical environmental remediation, i.e., the synthesis and characterization of mineral-based catalysts dominated by non-radical pathway, the large-scale application of PDS with low-cost, the surface modification of mineral-based catalysts with amphiphilicity, as well as the more efficient catalysts possessing nano-restricted domain catalytic effect. The development and expansion of novel and efficient mineral-based catalysts with enhanced synergistic effects would provide new opportunities for persulfate activation in environmental remediation. [ABSTRACT FROM AUTHOR]

Highlights: [•] We have prepared three amorphous silica minerals as supports for TiO2 catalysis. [•] We characterized by XRD, SEM, FT-IR, TEM and XPS. [•] We investigated the UV-assisted degradation of Rhodamine B (RhB). [•] TiO2/DE photocatalyst exhibits better catalytic performance at different calcined temperatures. [ABSTRACT FROM AUTHOR]

The catalytic membrane, which combines the physical barrier and peroxymonosulfate (PMS)/visible light (Vis)-induced catalytic oxidation functionalities while minimizing biofouling, exhibits great promise as a material for the removal of persistent organic pollutants from wastewater. In this study, three catalytic membranes composed of 2D/2D hybrid g-C 3 N 4 /kaolinite with nitrogen vacancies and modified with different iron species (γ-FeOOH nanosheets, Fe 2 O 3 quantum dots, and Fe single atoms) were prepared via vacuum filtration. Evaluation of the catalytic performance demonstrated that γ-FeOOH nanosheets-modified sample exhibited a relatively higher water flux (258.13 L m-2 h-1). In contrast, Fe single atom-modified sample achieved improved bisphenol A removal efficiency (97.39%) under the PMS/Vis synergetic system. Interestingly, the Fe 2 O 3 quantum dots-modified sample exhibited the highest rate constant based on the retention time. Furthermore, the Fe single atom-modified sample showed consistent removal of bisphenol A, reaching nearly 100% during continuous-flow operation for 180 min, while maintaining a flux of approximately 200 L m-2 h-1. Quenching experiments suggested that •O 2 −, 1O 2 , and h+ were the most important oxidizing species involved in the reaction of the three membranes. Statistical analysis indicated that variations in the average pore size of the membranes were key factors influencing the catalytic activity. Overall, this study offers an in-depth insight into the systematic and quantitative assessment of 2D/2D hybrid g-C 3 N 4 /layered clay-based catalytic membranes for wastewater treatment. [Display omitted] • The catalytic performance of three iron species-based membranes for bisphenol A removal were compared. • Fe single atom modified membrane showed more superior catalytic performance. • Fe 2 O 3 quantum dots modified membrane possessed the largest rate constant. • The catalytic performance was significantly correlated with surface area and average pore size. [ABSTRACT FROM AUTHOR]

• CuFe 2 O 4 was uniformly anchored on kaolinite to activate peroxymonosulfate (PMS). • Sulfate radicals are the primary radical species in CuFe 2 O 4 /kaolinite/PMS system. • CuFe 2 O 4 /kaolinite exhibited high catalytic activity and low leaching of metal ions. • More hydroxyl groups and accessible reactive sites enhanced its catalytic activity. • Low leaching of metal is ascribed to Fe O Al bond between CuFe 2 O 4 and kaolinite. In this study, CuFe 2 O 4 /kaolinite catalysts were fabricated through a facile citrate combustion method and were evaluated for their efficiency to activate peroxymonosulfate (PMS) towards the destruction of bisphenol A (BPA). The prepared catalysts were systematically characterized to explore the relationship between their characteristics and catalytic activities. In general, higher specific surface area, larger pore volume, more hydroxyl groups, and more accessible reactive sites of 40%-CuFe 2 O 4 /kaolinite contributed to the greater catalytic activity in peroxymonosulfate activation for BPA degradation compared to bare CuFe 2 O 4. Monodispersed CuFe 2 O 4 nanoparticles were uniformly anchored on the surface of kaolinite with Fe O Al bond, which prevented leaching of metal ions and contributed to the excellent reusability. The sulfate radicals produced in the CuFe 2 O 4 /kaolinite/PMS system were proved as the predominant radical species through electron spin resonance (ESR) and radical quenching experiments. Based on the results of X-ray photoelectron spectroscopy (XPS) and attenuated total reflectance – Fourier transform infrared spectra (ATR-FTIR), two main possible pathways of sulfate radicals generation were proposed: the generation and decomposition of Cu(II)-(HO)OSO 3 − (Cu(II)/Cu(III) and Cu(III)/Cu(II) redox reaction) and the oxidation of Fe(II). Moreover, the BPA degradation pathway was proposed through the identification of transformation products. This work provides an interesting insight for PMS activation by the high-efficient natural mineral-based catalysts for wastewater reclamation. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Natural kaolinite was used to activate peroxymonosulfate for the first time. • Surface-bonded and structural hydroxyl groups are responsible for PMS activation. • Kaolinite can be continuously reused to activate PMS without recovery. • OH and SO 4 − were identified as the primary reactive species. • The H 2 PO 4 − enhanced PMS decomposition and increased atrazine degradation. Abstract In this study, natural kaolinite, an abundant, low cost, thermally and chemically stable, and easily recyclable material was evaluated for the performance to activate peroxymonosulfate (PMS) by the degradation of atrazine. Based on radical quenching experiments and electron spinning resonance (ESR) spectra, hydroxyl radical (OH) and sulfate radical (SO 4 −) were identified to be the primary reactive species. The effects of catalyst loading, initial reaction pH, PMS dosage, initial atrazine concentration, and the presence of inorganic ions (Cl−, NO 3 −, HCO 3 − and H 2 PO 4 −) were also investigated in this work. Interestingly, the presence of H 2 PO 4 − enhanced the degradation efficiency of atrazine via promoting the decomposition of PMS. The transformation products were detected on a quadrupole time-of-flight liquid chromatography/mass spectrometer (Q-TOF-LC-MS) and the possible degradation pathway of atrazine was proposed. Based on comprehensive characterizations of crystal phase and crystallinity, porosity and pore structure, surface morphology, functional groups, and valence state of specific elements, the catalytic ability of natural kaolinite towards PMS is attributed to the abundant surface-bonded and structural hydroxyl groups. This study provides new insights of PMS activation by natural minerals for the degradation of refractory and deleterious contaminants in wastewater treatment. [ABSTRACT FROM AUTHOR]

Natural minerals are generally accepted as one of the most suitable carriers to support TiO 2 in photocatalytic and other applications because of their abundance, low cost, large surface area, and easy recyclability. Hence, in this work, a novel 0D/2D TiO 2 /kaolinite composite endowed with presence of oxygen vacancies and surface defect sites was synthesized through a mild sol-gel method combining with nitrogen induction. Ciprofloxacin (CIP) was taken as the main target organic pollutant to study the photocatalytic performance of the synthesized catalyst. The results showed that the nitrogen treated TiO 2 /kaolinite composite exhibited improving degradation performance for adsorption-photocatalytic elimination of CIP within broad radiation spectrum (200–800 nm). The synthesized composite exhibited enhanced reaction rate constant which is nearly 7.00, 2.54 and 3.13 times higher than that of bare TiO 2 treated with air under UV, solar, and visible light, respectively. Moreover, the newly prepared composite also exhibited significant enhancement towards the removal of formaldehyde under both UV and visible light. Radical scavenger experiments and ESR results indicated that holes should be the main oxidizing species within broad spectrum in the degradation system. The enhanced activity of nitrogen treated composite is mainly attributed to the induced oxygen vacancies as well as the intimate interface contact between TiO 2 and kaolinite, resulting in smaller grain size, higher light absorption ability, and faster carrier separation efficiency. It is expected that this high-efficiency composite photocatalyst based on natural minerals will be a promising candidate for the elimination of pharmaceutical and personal care products and volatile organic compounds within broad radiation spectrum. [ABSTRACT FROM AUTHOR]

Organo-rectorites (ORts) modified with different quaternary ammonium salts were prepared to remove polar mycotoxin aflatoxin B 1 (AFB 1 ) and weak polar, hydrophobic mycotoxin zearalenone (ZER). The structural and surface properties of the prepared ORts were studied. The intercalation of organic cationic surfactants expanded the interlayer of rectorite and increased the hydrophobicity. In vitro adsorption experiments were carried out to simulate the in vivo conditions of gastrointestinal tract of animals by a batch mode. The prepared ORts showed super enhanced adsorption capacities towards AFB 1 and ZER compared with raw rectorite, indicating the effectiveness of the prepared ORts as mycotoxins adsorbents. The ORts modified with longer chain surfactant molecules possessed a higher adsorption capacity towards mycotoxins. In addition, with increasing the modifier dosage, the adsorption capacity increased first and then decreased. The best adsorption capacity was achieved when the dosage of the modifier increased to 2.0CEC. The adsorption of both AFB 1 and ZER onto ORts could be well described by Langmuir model. In the binary-contaminant system, the existence of AFB 1 would bring negative effect to the adsorption of ZER. On the other hand, the adsorption of ZER was in favor of the adsorption of AFB 1 molecules. The solution pH had negligible influence on the adsorption process of ORts both in single system and binary system, indicating no desorption occurred when the adsorbents pass through from stomach to intestine as animal feed. This study demonstrates that the received ORts could be a promising adsorbent for detoxication of different mycotoxins in real application. [ABSTRACT FROM AUTHOR]

A novel 3D heterogeneous g-C 3 N 4 /TiO 2 /kaolinite composite with enhanced visible light activity was fabricated via a mild sol-gel method associated with chemical stripping and self-assembly. Compared with bare photocatalysts, the g-C 3 N 4 /TiO 2 /kaolinite 3D structure exhibits enhanced adsorption-photocatalytic degradation ability for the removal of ciprofloxacin (CIP) under visible-light irradiation, and also facilitate the recyclability of the photocatalyst as demonstrated from the reusability test. The apparent rate constant of the composite is up to around 5.35 times, 6.35 times and 4.49 times that of bare TiO 2 , g-C 3 N 4 and P25, respectively, and a possible degradation pathway was also proposed. On the other hand, the as-received composite also exhibited enriched disinfection ability towards S. aureus . It is indicated that the superoxide radical ( O 2 − ) is the main active species in the degradation process, and the superior photocatalytic performance of composite should be mainly attributed to both the improvement of light harvesting as well as the enhanced separation and transfer efficiency. It is expected that this novel ternary visible-light responding composite would be a promising candidate material for the organic pollutants degradation and bacteria inactivation. [ABSTRACT FROM AUTHOR]

In today's world of antibiotic abuse and bacterial resistance, it is urgent to propose a non-antibiotic solution against bacterial wound infections. Hence, the present work prepared kaolinite (KAO)-based organic antibacterial material (CA/KAO) modified with chlorhexidine acetate (CA) via a dry process. And the potential of CA/KAO in the doping preparation of antibacterial wound dressings was evaluated with poly(vinyl alcohol) (PVA) as an organic matrix. The results demonstrated that a synergistic promotion system between CA and kaolinite was formed. Kaolinite optimized the thermal stability of CA and controlled it to achieve a demand-oriented release mode of "burst + slow" release. CA was mainly attached to the surface of kaolinite by hydrogen bonding to impart its antibacterial properties and enhanced organic compatibility. For Staphylococcus aureus (S. aureus), which is prone to induce wound infections, CA/KAO showed a low-level MIC of 11.72 mg/L and achieved a 98.37% antibacterial rate by contact inactivation and released CA sterilization. CA/KAO was homogeneously dispersed in PVA film and achieved inhibition zones of 15.393 mm and 12.663 mm against S. aureus and Escherichia coli (E. coli) , respectively, at 30 wt% doping. It is expected that CA/KAO would be an option for the mass production of antibacterial wound dressings. [Display omitted] • Chlorhexidine/kaolinite antibacterial material was prepared by a simple dry process. • A synergistic promotion system was formed between chlorhexidine and kaolinite. • Chlorhexidine/kaolinite-doped poly(vinyl alcohol) films prepared by solution-casting method. • Antibacterial material for manufacturing high-quality wound dressings was provided. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel nZVI/kaolinite composite was prepared by liquid-phase reduction method. • nZVI particles with oxide layer were embedded into kaolinite surface and edges. • nZVI/kaolinite exhibits high efficiency for BPA removal with PMS activation. • SO 4 •− and 1O 2 were proved to be the main active components. • The possible degradation pathways were well analyzed and illustrated. Nano-zero valent iron/kaolinite (nZVI/kaolinite) composite was prepared by liquid-phase reduction method in the presence of sodium borohydride. Transmission Electron Microscope images demonstrated that spherical nZVI particles with oxide layer were successfully engaged into the kaolinite surface and edges, which was beneficial to the peroxymonosulfate (PMS) activation and bisphenol A (BPA) degradation. The prepared nZVI/kaolinite composite was endowed with excellent performance in removing BPA with the assistance of PMS, namely more than 95% BPA could be eliminated in 15 min. In contrast with alkaline environment, weak acid and neutral environment were more advantageous to the BPA degradation. All the anions like Cl−, SO 4 2−, HCO 3 − and H 2 PO 4 − were adverse to the BPA degradation in nZVI/kaolinite/PMS system. Furthermore, EPR and radical quenching experiments proved that SO 4 •− and 1O 2 were the main active components during the series reactions. The possible degradation pathways were also inferred based on the liquid chromatography-mass spectrometry (LC-MS) results. Besides, the nZVI/kaolinite composite displayed good performance toward coking wastewater as well. This study is of great significance in designing of efficient persulfate activated materials and treating wastewater. [ABSTRACT FROM AUTHOR]

Based on the urgency of comprehensive utilization of large amount of coal gangue and the demand for the treatment of organic pollution in coal chemical sites and water bodies, novel coal gangue-based persulfate catalytic material (GCM) which can effectively activate peroxymonosulfate (PMS) were prepared by using coal gangue as raw material and adding activator under inert atmosphere. Under the optimized conditions, the degradation rate of GCM-ZnCl 2 material can reach 82.6% in 25min. Among different environmental impact factors, anions have little effect on the degradation rate of phenol, while the initial pH value has a greater impact. When the pH value is 9.0, it belongs to the synergistic effect of alkali activation, and the degradation effect of phenol is relatively better. The GCM-ZnCl 2 material can realize the efficient adsorption of phenol through its large specific surface area and pore volume, and provide more catalytic active sites. The oxygen-containing groups C O (carboxyl, ester, ketone, etc.) on its surface can react with PMS to produce free radical SO 4 •− or induce the production of non-free radical 1O 2 , so as to realize the efficient degradation of phenol. [Display omitted] • Novel coal gangue-based persulfate catalytic materials (GCM) were prepared. • The GCM-ZnCl 2 catalytic material has a large specific area of 141.4 m2/g. • The removal rate of phenol reached 82.6% within 25 min. • Both free radical (.•OH and SO 4 •−) and non-free radical (1O 2) involved in the reaction. • The possible degradation pathways were well analyzed and illustrated. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel γ-FeOOH/g-C 3 N 4 /kaolinite composite was fabricated via two-step strategy. • Efficient electron transfer induced by γ-FeOOH and N vacancies promote the separation and migration of photo-generated carriers. • γ-FeOOH/g-C 3 N 4 /kaolinite catalyst possessed good bisphenol A removal efficiency. • The potential synergistic enhancement mechanism was well proposed. A novel ternary composite with the flower-like structure was synthesized by integrating of γ-FeOOH and g-C 3 N 4 /kaolinite containing N vacancies (FNGK). The FNGK-10 composite exhibited the superiority of bisphenol A (BPA) degradation in the presence of peroxymonosulfate (PMS) under the visible-light irradiation with the outstanding reusability and universal applicability, in which the degradation rate constant of FNGK-10/PMS/Vis system was about 3.25 and 8.42 times higher than that of FNGK-10/PMS and FNGK-10/Vis system, respectively. Moreover, the introduction of kaolinite leads to the accelerated consumption of PMS. The FTIR, EPR and XPS spectra proved that the formation of Fe-N and cyano (C≡N) bonds induced the enhancement of the efficiency of electron transfer. The photo-generated carriers could be trapped by N vacancies and γ-FeOOH, which was favorable for the separation potency of photoexcited charge carriers and reduction efficiency of Fe(III) to Fe(II). This paper gave a new perspective on the coupling application of PMS activation and photocatalytic technology to efficiently degrade organic contaminants. [ABSTRACT FROM AUTHOR]

Abstract: This study presented a novel method for purification of three different grades of diatomite from China by scrubbing technique using sodium hexametaphosphate (SHMP) as dispersant combined with centrifugation. Effects of pH value and dispersant amount on the grade of purified diatomite were studied and the optimum experimental conditions were obtained. The characterizations of original diatomite and derived products after purification were determined by scanning electron microscopy (SEM), X-ray diffraction (XRD), infrared spectroscopy (IR) and specific surface area analyzer (BET). The results indicated that the pore size distribution, impurity content and bulk density of purified diatomite were improved significantly. The dispersive effect of pH and SHMP on the separation of diatomite from clay minerals was discussed systematically through zeta potential test. Additionally, a possible purification mechanism was proposed in the light of the obtained experimental results. [Copyright &y& Elsevier]

Over the past decades, inspired by the outstanding properties of clay minerals such as abundance, low-cost, environmental benignity, high stability, and regularly arranged silica-alumina framework, researchers put much efforts on the interface assembly and surface modification of natural minerals with bare photocatalysts, i.e. TiO 2 , g-C 3 N 4 , ZnO, MoS 2 , etc. The clay-based hybrid photocatalysts have resulted in a rich database for their tailor-designed microstructures, characterizations, and environmental-related applications. Therefore, in this study, we took a brief introduction of three representative minerals, i.e. kaolinite, montmorillonite and rectorite, and discussed their basic merits in photocatalysis applications. After that, we summarized the recent advances in construction of stable visible-light driven photocatalysts based on these minerals. The structure-activity relationships between the properties of clay types, pore structure, distribution/dispersion and light absorption, carrier separation efficiency as well as redox performance were illustrated in detail. Such representative information would provide theoretical basis and scientific support for the application of clay based photocatalysts. Finally, we pointed out the major challenges and future directions at the end of this review. Undoubtedly, control and preparation of novel photocatalysts based on clays will continue to witness many breakthroughs in the arena of solar-driven technologies. [Display omitted] • Kaolinite, montmorillonite and rectorite based photocatalysts were well reviewed. • The role of clay in composite photocatalysts was illustrated in detail. • We point out the major challenges and direction of clay based photocatalysts. • This review is meaningful for energy crisis and environmental remediation. [ABSTRACT FROM AUTHOR]

Developing low-cost, high-efficiency catalysts for advanced oxidation processes remain a key issue for the degradation of organic pollutants. In this study, a novel FeCo 2 O 4 /rectorite composite was synthesized via a facile combustion process and employed to activate peroxymonosulfate (PMS) for dealing with atrazine (ATZ). The addition of rectorite could result in higher specific surface area, smaller pore size and more hydroxyl groups, which were beneficial to enrich pollutants to the adsorption sites and provide sufficient reactive sites. After meticulous evaluation, the degradation efficiency of FeCo 2 O 4 /rectorite composite towards ATZ exhibited improved PMS activation efficiency which was about 2.6 times than that of pure FeCo 2 O 4. Based on the characterization results, the sulfate radicals and hydroxyl radicals were considered to be the main free radicals which were involved into the circulation of Co(II)–Co(III)–Co(II) as well as the oxidation of ≡Fe(II), which was responsible for the remarkable catalytic efficiency. In addition, the chemical stability and superior catalytic performance of FeCo 2 O 4 /rectorite should also be attributed to the chemical combination between metal ions and the surface hydroxyl groups of rectorite. Overall, these findings are beneficial for understanding the mechanism of PMS activation by natural mineral-based catalysts and contributing to the practical application of sulfate-based technology for organic wastewater treatment. Image 1 • In situ growth of FeCo 2 O 4 on natural rectorite for PMS activation was achieved. • FeCo 2 O 4 /rectorite composite exhibited higher PMS activation efficiency than pure FeCo 2 O 4. • Hydroxyl groups of rectorite accelerated PMS activation significantly via combining with metal oxide. • Both OH• and SO 4 •− were identified as main reactive species. [ABSTRACT FROM AUTHOR]

• Carbon doped TiO 2 /kaolinite composite was rationally designed and assembled. • The composite's reaction rate constant is about 25 times higher than that of pure TiO 2. • TiIII defects and localized occupied states are responsible for performance enhancement. • Kaolinite induced carrier effect plays important role in catalytic activity enhancement. • The composite material might be a promising candidate for degrading trace amounts of pollutants. In this work, kaolinite supported monodispersed TiO 2 with carbon regulation was prepared through rational design and different dimensions' assembly, leading to generation of TiIII species in carbon doped TiO 2 /kaolinite (C-TiO 2 /kaolinite) composite. The C-TiO 2 /kaolinite composite exhibited improved degradation performance towards ciprofloxacin under visible light, with a reaction rate constant of 0.00597 min−1, which is about 3.24 and 24.88 times higher than that of 2.0C-T (2.0% carbon-doped TiO 2) and pure TiO 2 , respectively. Based on various materials characterization methods and DFT calculations, it was indicated that the electronic structure was correlated with the changes in light absorption, charge carrier lifetime, and reactive oxygen species (ROS). The enhanced visible light responding ability could be attributed to the synergistic effect between natural kaolinite and nanosized TiO 2 , the formation of localized occupied states in the gap, and the formation of TiIII defects consisted of surface oxygen vacancies. All of them effectively increase the separation efficiency, migration velocity, and lifetime of the photoinduced charge carriers under visible-light irradiation. Overall, our study provides a promising candidate for effective degradation of trace amounts of pharmaceutical and personal care products and other highly toxic contaminants with the assistance of solar light. [ABSTRACT FROM AUTHOR]

A novel CoNi 3 O 4 /diatomite hybrid is constructed through vertically oriented growth of 2D CoNi 3 O 4 nanoribbons with atomic layer-thickness on cost-effective diatomite template. Distinct from stacked CoNi 3 O 4 with a large portion of "dead surface", diatomite derived CoNi 3 O 4 nanoribbons possess abundant exposed edges, sharp corners, and open diffusion channels. These unique characteristics offer CoNi 3 O 4 /diatomite hybrid excellent peroxymonosulfate activation efficiency in real water bodies. • 2D CoNi 3 O 4 nanoribbons were fabricated via vertically oriented growth on diatomite. • CoNi 3 O 4 /diatomite showed rich exposed edges, sharp corners and diffusion channels. • CoNi 3 O 4 /diatomite presented excellent PMS catalytic activity in real water bodies. • S O 4 - • , OH and 1O 2 were generated and functioned in CoNi 3 O 4 /diatomite/PMS system. • O 2 − contributed to reversible redox cycle of Co2+/Co3+ and Ni2+/Ni3+. The reactive oxygen radicals generated by peroxymonosulfate (PMS) activation exhibit great potential to deal with refractory contaminants of emerging concern. However, mass production of efficient and cost-effective catalysts for PMS activation is still a long-term goal for its widespread practical application. Herein, a novel CoNi 3 O 4 /diatomite hybrid is constructed through vertically oriented growth of 2D CoNi 3 O 4 nanoribbons with atomic layer-thickness on cost-effective diatomite template. Distinct from stacked CoNi 3 O 4 , CoNi 3 O 4 /diatomite composite possesses abundant exposed edges, sharp corners, and open diffusion channels. Abundant exposed edges and sharp corners create more open space and active sites for PMS activation. Open diffusion channels accelerate the migration of PMS and contaminants. Such characteristics offer CoNi 3 O 4 /diatomite hybrid excellent PMS activation efficiency. Furthermore, sulfate radical plays the dominant role in atrazine degradation. Superoxide radical contributes to reversible redox cycle of Co2+/Co3+ and Ni2+/Ni3+. This study provides a novel strategy for cost-effective mass production of various Fenton-like 2D catalysts. [ABSTRACT FROM AUTHOR]

• Diatomite and CoFe 2 O 4 was effectively assembled to activate peroxymonosulfate. • CoFe 2 O 4 /diatomite catalyst has lower metal dissolution rate. • Surface structure and crystallization dispersion improve activation performance. • The 1O 2 was the primary active substance for BPA degradation. • Weak basic condition enhanced PMS activation and increased BPA degradation. Porous magnetic CoFe 2 O 4 /diatomite catalyst (CFD) was rationally synthesized via a facile citrate combustion process. The relationship between catalytic performance and material properties of the prepared catalysts was comprehensively investigated by various characterizations, especially for the interface interaction between CoFe 2 O 4 and diatomite as well as crystallization regulation of CoFe 2 O 4. Overall, higher specific surface area, overspreading surface hydroxyl groups, better crystal dispersion and abundant surface-active sites make CFD have better degradation performance of bisphenol A (BPA) than pure CoFe 2 O 4 in the presence of peroxymonosulfate (PMS), and the pseudo-first-order reaction rate constant of 40-CFD (40% CoFe 2 O 4 /diatomite) is almost 5.32 times higher than that of pure CoFe 2 O 4. Besides, CFD has excellent magnetic properties, lower metal dissolution rate and good reusability. In addition, electron paramagnetic resonance (EPR) and radical quenching experiments show that sulfate radicals (SO 4 −) and singlet oxygen radicals (1O 2) generated from the electron transfer of BPA molecule and valence state change of transition metals should be the predominant oxidation species. Moreover, possible degradation pathways of BPA are determined by the detection of intermediates derived from the results of liquid chromatograph–mass spectrometer (LC–MS). In brief, it is indicated that the CoFe 2 O 4 /diatomite composite material is an efficient and environmentally friendly catalyst, which has a great potential application in wastewater treatment by activating PMS. [ABSTRACT FROM AUTHOR]

• Oxygen-vacancy-rich Co 3 O 4 /illite can activate peroxymonosulfate (PMS) efficiently. • Modulating crystallization of Co 3 O 4 by illite resulted in rich oxygen vacancies. • Theoretical calculations were employed to elucidate catalytic mechanism for PMS. • Rich oxygen vacancies accelerated electron-transfer and reduced adsorption energy. • S O 4 - • , OH and 1O 2 were generated and functioned in Co 3 O 4 /illite/PMS system. Natural illite microsheets were firstly utilized to induce oxygen vacancies into ultrafine cobalt oxide (Co 3 O 4) for highly efficient Fenton-like catalysis via activation of peroxymonosulfate (PMS). The results indicated that presence of illite microsheets regulated multi-directional crystallization of Co 3 O 4 nanospheres and resulted in reduced grain size and crystallinity. The smaller grain size provided more reactive edge sites for PMS catalysis. The numerous indistinct lattice boundaries caused by reduced crystallinity created abundant oxygen vacancies. Density functional theory (DFT) calculations illustrated that presence of oxygen vacancies significantly reduced adsorption energy and accelerated electron transfer, which further faciliated PMS activation. The oxygen vacancy-rich Co 3 O 4 /illite exhibited superior catalytic efficiency in real water matrix. Apart from sulfate and hydroxyl radicals, singlet oxygen generated from oxygen vacancy-based reaction pathway also played a significant role in atrazine degradation. This strategy provided a new insight for future designing of natural mineral-based catalysts for efficient wastewater treatment via Fenton-like process. [ABSTRACT FROM AUTHOR]