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In recent years, the primary power sources for portable electronic devices are lithium ion batteries. However, they suffer from many of the limitations for their use in electric means of transportation and other high level applications. This mini-review discusses the recent trends in electrode materials for Li-ion batteries. Elemental doping and coatings have modified many of the commonly used electrode materials, which are used either as anode or cathode materials. This has led to the high diffusivity of Li ions, ionic mobility and conductivity apart from specific capacity. Many of the newly reported electrode materials have been found to deliver a better performance, which has been analyzed by many parameters such as cyclic stability, specific capacity, specific energy and charge/discharge rate. Hence, the current scenario of electrode materials of Li-ion batteries can be highly promising in enhancing the battery performance making it more efficient than before. This can reduce the dependence on fossil fuels such as for example, coal for electricity production. Keywords: Li-ion, Battery, Cathode, Anode, Electrode

In an effort to produce new lead antimycobacterial compounds, herein we have reported the synthesis of a sequence of new pyrrolyl benzamide derivatives. The new chemical entities were screened to target enoyl-ACP reductase enzyme, which is one of the key enzymes of M. tuberculosis that are involved in type II fatty acid biosynthetic pathway. Compound 3q exhibited H-bonding interactions with Tyr158, Thr196 and co-factor NAD+ that binds the active site of InhA. All the pyrrolyl benzamide compounds were evaluated as inhibitors of M. tuberculosis H37Rv as well as inhibitors of InhA. Among them, few representative compounds were tested for mammalian cell toxicity on the human lung cancer cell-line (A549) and MV cell line that presented no cytotoxicity. Five of these compounds exhibited a good activity against InhA.

Solid membranes for degradation of emerging contaminants such as atrazine is of significant interest for water engineering applications. In this study, nanocatalyst particles have been anchored on vertically-aligned carpet-like arrays of carbon nanotubes (CNT) grown on porous carbon foams. This hierarchical architecture combines the advantages of highly surface-active nanoparticles with the robust and reusable structural advantage of porous solid membranes suitable for water treatment devices. Three types of palladium-based nano-catalytic surfaces have been investigated: metallic palladium (Pd), Pd nanoparticle with a layer of oxide (PdO-coated Pd), and Pd nanoparticle coated with thin film of silver (Ag-Pd). Their catalytic activities have been compared by analysing the degradation rate of atrazine in water. It is noted that all three catalysts show high levels of atrazine degradation, with the PdO-coated nanoparticles showing the highest kinetics. These results demonstrate that hierarchical hybrid architectures can provide compact and powerful surface-active materials such as adsorbents and catalytic degradation devices in future water treatment applications.

Per- and polyfluoroalkyl substances (PFAS) are a large group of perfluorinated organic molecules that have been in use since the 1940s for industrial, commercial, and consumer applications. PFAS are a growing concern because some of them have shown persistent, bioaccumulative and toxic effects. Herein, we demonstrate an innovative technology of UV-vis/Zn

This investigation is first to elucidate the synthesis of mono-dispersed ZnS/NiO-core/shell nanostructures with a uniform thin layer of NiO-shell on the ZnS-nanospheres as a core under controlled thermal treatments. NiO-shell thickness varied to 8.2, 12.4, 18.2, and 24.2 nm, while the ZnS-core diameter remained stable about 96 ± 6 nm. The crystalline phase and core/shell structure of the materials were confirmed using XRD and HRTEM techniques, respectively. Optical properties through UV-vis spectroscopy analysis revealed the manifestation of red-shift in the absorption spectrum of core/shell materials, while the XPS analysis of elements elucidated their stable oxidation states in ZnS/NiO core/shell structure. The optimized ZnS/NiO-core/shell showed 1.42 times higher H

Following a pH reduction in their drinking water over a span of more than 20 years, the City of Newark, New Jersey, has struggled with elevated lead (Pb) release from Pb service lines and domestic plumbing in the zone fed by the Pequannock Water Treatment Plant. In response, Newark initiated orthophosphate addition and provided faucet-mounted point-of-use (POU) filters and pitcher filters certified for Pb and particulate reduction under NSF/ANSI Standards 53 and 42 to residential homes in that zone. Water chemistry analysis and size fractionation sampling were performed at four of these houses. Analysis of the particulate material retained by the fractionation filters revealed that Pb was dominantly present in the water as fine Pb(II) orthophosphate particles. A considerable amount of the particulates occurred as a nanoscale fraction that sometimes passed through the POU faucet or pitcher filtration units. Scanning electron microscopy, transmission electron microscopy, and energy-dispersive spectroscopy analyses showed that the nanoparticles (

The ubiquitous presence of poly- and perfluoroalkyls (PFAS) is a severe concern in view of their bioaccumulation and persistence in the environment because of strong C − F bonds (485 kJ/mol) that are recalcitrant towards thermal, chemical, and biological decomposition. The predominance of PFAS having toxicological effects can be quite hazardous to environment, wildlife, and human beings, especially the children. Efforts are continuously pursued to investigate complete mineralization of PFAS to detect and destroy these chemicals from the environment. Of all the many methods used, electrochemical approach is promising. This review explores the latest advances and limitations of the electrochemical treatment methods of PFAS. Recent findings emphasize the use of boron-doped diamond (BDD) anodes and titanium sub-oxide ceramic anodes, specifically Magneli phase Ti4O7 electrode as these can achieve almost ∼ 99% of PFAS removal with the least energy requirement compared to other existing anodes. The influence of design parameters and electrode materials are considered and the mechanisms of electro-oxidation of PFAS onto anodic surface degradation, besides the various side-products formed after the process are analyzed. The viability of macroscale application of electrochemical treatment faces some obstructions because of the concentration effects and mass transfer limitations. Reactive electrochemical membrane operation could facilitate inter-phase mass transfer through the filtration of contaminated samples over the porous materials that can act as a membrane plus anode all at once. Adopting different techniques such as nanofiltration, ion exchange resin, and reverse osmosis with electro-oxidation may boost the system effectiveness to reduce the overall expenses as well as alleviate the concentration of unfavorable and harmful side products after the degradation of PFAS. Nonetheless, an assessment of different electrode materials, consideration of realistic conditions, and implementation of feasible and workable approaches are essential for the scalability of laboratory research to large-scale applications.

Graphitic carbon nitride supported palladium nanoparticles, Pd@g-C3N4, have been synthesized and utilized for the direct oxidative esterification of alcohols using atmospheric oxygen as a co-oxidant via photocatalytic C H activation.

Graphitic carbon nitride supported palladium nanoparticles, Pd@g-C(3)N(4), have been synthesized and utilized for the direct oxidative esterification of alcohols using atmospheric oxygen as a co-oxidant via photocatalytic C-H activation.

Degradation of atrazine, a widely-used herbicide, by a novel advanced oxidation process was investigated through photo-catalyzing sulfite, the precursor of sulfate radical (SO4 −) in this study, by zinc-copper ferrites (ZnxCu1−xFe2O4) under UV–vis light irradiation. The ZnxCu1−xFe2O4 with different ratios of Zn to Cu was synthesized through a facile sol-gel combustion method, and characterized by X-ray powder diffractometry, scanning electron microscopy, transmission electron microscopy, porosimetry, and UV–vis diffuse reflectance spectroscopy, and by a vibrating sample magnetometer and Mossbauer spectrometer. The Zn0.8Cu0.2Fe2O4 demonstrated the highest photocatalytic ability to activate sulfite for the degradation of atrazine under current experimental conditions. The sulfate radical generated in the UV–vis light/Zn0.8Cu0.2Fe2O4/sulfite system was identified as the main reactive species through radical quenching experiments and measuring two important byproducts (atrazine-desethyl and atrazine-desisopropyl). The XPS spectra of fresh and used catalysts were analyzed to further elucidate the reaction mechanisms. There are two possible approaches to produce SO4 −: the oxidation of sulfite by photo-generated holes and the accelerated decomposition of metal-sulfito complexes (Fe(III)-sulfito and Cu(II)-sulfito) on the surface of Zn0.8Cu0.2Fe2O4. Based on the detected byproducts, the transformation pathways of atrazine by UV–vis light/Zn0.8Cu0.2Fe2O4/sulfite were proposed as well. After the complete decomposition of atrazine, the used catalysts could be magnetically recovered using a magnet and no sulfite remained in the system. The results suggest that the UV–vis light/Zn0.8Cu0.2Fe2O4/sulfite system is a “green” advanced oxidation technology for future application in wastewater treatment.

Magnetic spinel cobalt ferrite nanoparticles with variable composition (CoxFe3-xO4; x = 0.1, 0.5, 0.7 and 1.0) were synthesized. The nanoparticles were characterized by various surface techniques. Average sizes and surface areas of ferrites were determined in the ranges of 11–34 nm and 18.5–49.1 m2/g, respectively. Surface analysis of the nanoparticles confirmed the spinel type structures in which Co(II) incorporated into the crystal lattice. The synthesized catalysts were used to dissociate peroxomonosulphate (PMS) into reactive sulfate radicals ( SO 4 • − ) and further into hydroxyl radicals ( H O • ) to degrade a target pollutant, 2-phenylbenzimidazole-5-sulfonic acid (PBSA) in absence of heat and light. As the molar ratio of cobalt (i.e., x) in the ferrite catalyst increased from 0.1 to 1.0, PBSA degradation enhanced from 24 to 75% in 240 min. The removal of PBSA increased significantly with the increase in PMS concentration up to 0.1 mM, followed by a decrease at PMS levels of >0.1 mM. Nitrogen content in PBSA was mineralized by the cobalt ferrite-PMS system mostly into NO3− and NH4+ ions with minor formation of NO2−. Only 32% TOC removal was observed over a 240 min reaction time, indicating carbon content in PBSA was not completely mineralized. A chemical probe method, based on free radical scavenging, revealed the contribution of both SO 4 • − and H O • species in PBSA degradation. Fifteen reaction intermediates were identified using LC/Q-TOF-ESI–MS analysis. Hydroxylation, elimination of sulfonate moiety, and ring cleavage processes were involved in the major degradation pathways. Catalyst reuse experiments demonstrated PBSA degradation efficiency either retained or increased with each subsequent reuse. The magnetic spinel Co-ferrite nanoparticles can be applied effectively to activate PMS without energy aiding for degrading harmful emerging organic contaminants in water.

Goethite with protuberant lychee morphology has been synthesized that accomplishes C-H activation of N-methylanilines to generate α-aminonitriles; the catalyst takes oxygen from air and uses it as a co-oxidant in the process.

Photocatalytic CO2 reduction is the key strategic factor to mitigate the detrimental consequences arising from greenhouse gases (predominantly anthropogenic CO2). Products (CH4, C2H6, CH3OH, C2H5OH, etc.,) that are derived from the reduction of CO2 could be promising alternatives to petro-derived fuel/chemicals. Even though a great deal of efforts has been devoted to increase the conversion efficiency of CO2, the technical readiness level (TRL) has not yet been fully matured. This review emphasizes on the emerging functional material ultrathin two-dimensional (2D) nanosheet graphitic carbon nitride (g-C3N4) for the reduction of CO2 into value-added products. Physico-chemical properties of 2D-cabon nitride (sizeable surface-to-volume ratio, supplementary active sites onto the surface, shorter diffusion length, bandgap tuning, atomic thickness, and bulk to surface charge transportation) governing the photocatalytic activity are discussed. This review provides recent advances in 2D-carbon nitride photocatalysts to highlight the ongoing challenges and new strategies to optimize their functionality for improved selectivity for CO2 conversion.

Over the past decade, anthropogenic CO2 emission is among one of the foremost concerns of the environmental issues. Numerous efforts have been focused on utilizing visible-light active emerging graphene-based catalysts since recently these nanomaterials are being widely explored for the generation of solar fuels, a step towards sustainability. Tuning between the band gaps, metal-free nature, high surface area leading to higher dispersion, and promoting high CO2 adsorption made graphene as the material of choice. However, its shortcomings, such as faster recombination rate and photo-corrosion, have slightly hindered its growth. The role of 2D graphene and its various modifications as well as heterojunctions is thoroughly discussed in this review. Opportunities and challenges on CO2 transformation with low selectivity and reactivity are covered. Mainly, the review contributes towards the expansion of emerging graphene-based semiconductors as the budding candidates for solar fuel conversion to improved outlooks for researchers working in this area.

Microplastics (MPs) and nanoplastics (NPs) have gained much attention in recent years because of their ubiquitous presence, which is the widely acknowledged threat to the environment. MPs can be

Per- and polyfluoroalkyl substances (PFAS) are a large group of perfluorinated organic molecules that have been in use since the 1940s for industrial, commercial, and consumer applications. PFAS are a growing concern because some of them have shown persistent, bioaccumulative and toxic effects. Herein, we demonstrate an innovative technology of UV–vis/ZnxCu1-xFe2O4/oxalic acid for the degradation of perfluorooctanoic acid (PFOA) in water. The magnetically retrievable nanocrystalline heterogeneous ferrite catalysts, ZnxCu1-xFe2O4 were synthesized using a sol-gel auto-combustion process followed by calcination at 400 °C. The combination of ZnxCu1-xFe2O4 and oxalic acid generate reactive species under UV light irradiation. These reactive species are then shown to be capable of the photodegradation of PFOA. The degree of degradation is tracked by identifying transformation products using liquid chromatography coupled with quadrupole time-of-flight mass spectroscopy (LC-QTOF-MS).

Nonselective oxidation of organic chemicals during TiO2 photocatalytic water treatment significantly prohibits decomposition of toxic target contaminants, particularly in the presence of naturally abundant less toxic natural organic matter (NOM). To minimize the adverse effect of NOM, the authors have investigated physical size exclusion of large NOM onto mesoporous TiO2 photocatalysts, which allows small target contaminants to selectively access the porous structure for subsequent chemical reaction. Various treatment scenarios tested with different targets (ibuprofen, microcystin-LR) and competitors (humic acid, polyethylene glycol), and a series of mesoporous TiO2 materials proved the size exclusion mechanism. Discussion was made on the impact of the porous structure of TiO2 on selectivity and reactivity, considering size difference among targets < TiO2 pores < competitors as well as mass transfer limitation of even a target to small pores. This simple approach would greatly improve the photocatalytic treatment of toxic chemicals in water containing NOM.

Rapidly developing polymeric micelles as potential targeting carriers has intensified the need for better understanding of the underlying principles related to the selection of suitable delivery materials for designing, characterizing, drug loading, improving stability, targetability, biosafety and efficacy. The emergence of advanced analytical tools such as fluorescence resonance energy transfer and dissipative particle dynamics has identified new dimensions of these nanostructures and their behavior in much greater details. This review summarizes recent efforts in the development of polymeric micelles with respect to their architecture, formulation strategy and targeting possibilities along with their preclinical and clinical aspects. Literature of the past decade is discussed critically with special reference to the chemistry involved in the formation and clinical applications of these versatile materials. Thus, our main objective is to provide a timely update on the current status of polymeric micelles highlighting their applications and the important parameters that have led to successful delivery of drugs to the site of action.

Chitosan-derived, porous nitrogen-enriched carbonaceous carbon nitride catalyst (PCNx) has been synthesized from marine waste and its use demonstrated in a metal-free heterogeneous selective oxidation of 5-hydroxymethyl-furfural (HMF) to 2,5-furandicarboxylic acid (FDCA) using aerial oxygen under mild reaction conditions.

This investigation is first to elucidate the synthesis of mono-dispersed ZnS/NiO-core/shell nanostructures with a uniform thin layer of NiO-shell on the ZnS-nanospheres as a core under controlled thermal treatments. NiO-shell thickness varied to 8.2, 12.4, 18.2, and 24.2 nm, while the ZnS-core diameter remained stable about 96 ± 6 nm. The crystalline phase and core/shell structure of the materials were confirmed using XRD and HRTEM techniques, respectively. Optical properties through UV–vis spectroscopy analysis revealed the manifestation of red-shift in the absorption spectrum of core/shell materials, while the XPS analysis of elements elucidated their stable oxidation states in ZnS/NiO core/shell structure. The optimized ZnS/NiO-core/shell showed 1.42 times higher H2 generation (162.1 mmol h−1 g−1cat) than the pristine ZnS-core (113.2 mmol h−1 g−1cat), and 64.5 times higher than the pristine NiO-shell (2.5 mmol h−1 g−1cat). The quantum efficiency at wavelengths of 420, 365 nm, and 1.5 G air mass filters was found to be 13.5%, 25.0%, and 45.3%, respectively. Water splitting experiments was also performed without addition of any additives, which showed enhanced H2 gas evolution of 1.6 mmol h−1 g−1cat under the sunlight illumination. Photoelectrochemical measurements revealed the stable photocurrent density and minimized charge recombination in the system. The performed recyclability and reusability tests for five recycles demonstrated the excellent stability of the developed photocatalysts.

The availability of organic matters in vast quantities from the agricultural/industrial practices has long been a significant environmental challenge. These wastes have created global issues in increasing the levels of BOD or COD in water as well as in soil or air segments. Such wastes can be converted into bioenergy using a specific conversion platform in conjunction with the appropriate utilization of the methods such as anaerobic digestion, secondary waste treatment, or efficient hydrolytic breakdown as these can promote bioenergy production to mitigate the environmental issues. By the proper utilization of waste organics and by adopting innovative approaches, one can develop bioenergy processes to meet the energy needs of the society. Waste organic matters from plant origins or other agro-sources, biopolymers, or complex organic matters (cellulose, hemicelluloses, non-consumable starches or proteins) can be used as cheap raw carbon resources to produce biofuels or biogases to fulfill the ever increasing energy demands. Attempts have been made for bioenergy production by biosynthesizing, methanol, n-butanol, ethanol, algal biodiesel, and biohydrogen using different types of organic matters via biotechnological/chemical routes to meet the world's energy need by producing least amount of toxic gases (reduction up to 20-70% in concentration) in order to promote sustainable green environmental growth. This review emphasizes on the nature of available wastes, different strategies for its breakdown or hydrolysis, efficient microbial systems. Some representative examples of biomasses source that are used for bioenergy production by providing critical information are discussed. Furthermore, bioenergy production from the plant-based organic matters and environmental issues are also discussed. Advanced biofuels from the organic matters are discussed with efficient microbial and chemical processes for the promotion of biofuel production from the utilization of plant biomasses.

Edible crops are widely used as biomass feedstocks for the production of liquid biofuels (bioethanol and biodiesel). However, the use of edible crops as feedstocks for the biofuels causes global food supply issues and ethical dilemma. Livestock waste materials, specifically animal manures, contain all the available feedstocks (carbohydrate, lipid, and protein) for the production of diverse biofuels. In addition, the massive production of livestock manures offers their potential use as plentiful feedstocks for biofuels. Nevertheless, they are used for only limited applications such as soil amendment and combustion. In this review, the suitability of livestock manures to be used as different biofuels is comprehensively discussed comparing to the current technical development for bioenergy synthesis processes. The economic feasibility of manure derived biofuels is compared with that from the other biomass resources. Lastly, the challenges of current technical developments and the future research directions for biofuel production from the livestock manures are provided.

A flexible, durable, and reusable nanocatalyst system was fabricated by anchoring palladium nanoparticles on carbon nanotube (CNT) carpets covalently attached to carbon cloth. These hierarchical hybrid materials were tested for catalytic degradation of triclosan (TCS), an emerging contaminant. Materials were characterized using scanning & transmission electron microscopy techniques (SEM and TEM), X-Ray Diffraction (XRD), and X-Ray Photoelectron Spectroscopy (XPS). The reaction kinetics was studied using HPLC and reaction pathways proposed based on LC-MS/GC-MS analyses. In the presence of hydrogen, complete step-wise chlorine removal was seen until complete dechlorination was accomplished. The pseudo-first-order rate constant was measured to be orders of magnitude higher than earlier reported values. Moreover, the same material was usable for multiple cycles in flowing water. This study demonstrates that robustness and reusability of larger structural materials can be combined with the ultra-high surface activity of nanocatalysts to provide practical and eco-friendly solutions for water sustainability.

Magnetic calcium (Ca) and magnesium (Mg)-modified iron oxide adsorbents were synthesized using CaCl 2 , CaCO 3 , MgCl 2 , or MgCO 3 by a simple combustion method for the remediation of phosphate. Modification with Ca and Mg significantly improved the phosphate adsorption capacity of the magnetic iron oxide adsorbents. Additionally, polyvinyl alcohol (PVA) was incorporated during synthesis to aid in the magnetism of the samples, making the adsorbents easy to separate from solutions. Physicochemical properties of the adsorbents were determined by characterization with X-ray diffraction (XRD), particle analyzer, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high resolution TEM (HR-TEM). Batch adsorption experiments were carried out to gain insight on the materials' ability to remove phosphate from water supplies. Samples without the addition of PVA had higher phosphate capacities (ranging from 16.92 to 16.97 mg g −1 ) compared to PVA-containing samples (ranging from 12.39 to 16.74 mg g −1 ), yet the PVA-containing samples were magnetic and thus, easily separable.

This paper proposes a robustness analysis based on Multiple Criteria Decision Aiding (MCDA). The ensuing model was used to assess the implementation of green chemistry principles in the synthesis of silver nanoparticles. Its recommendations were also compared to an earlier developed model for the same purpose to investigate concordance between the models and potential decision support synergies. A three-phase procedure was adopted to achieve the research objectives. Firstly, an ordinal ranking of the evaluation criteria used to characterize the implementation of green chemistry principles was identified through relative ranking analysis. Secondly, a structured selection process for an MCDA classification method was conducted, which ensued in the identification of Stochastic Multi-Criteria Acceptability Analysis (SMAA). Lastly, the agreement of the classifications by the two MCDA models and the resulting synergistic role of decision recommendations were studied. This comparison showed that the results of the two models agree between 76% and 93% of the simulation set-ups and it confirmed that different MCDA models provide a more inclusive and transparent set of recommendations. This integrative research confirmed the beneficial complementary use of MCDA methods to aid responsible development of nanosynthesis, by accounting for multiple objectives and helping communication of complex information in a comprehensive and traceable format, suitable for stakeholders and/or decision-makers with diverse backgrounds. (C) 2017 The Authors. Published by Elsevier Ltd.

Harmful algal blooms (HABs) found in various water bodies worldwide have been a huge concern due to their adverse impacts on human health and ecosystems. In particular, HABs associated with cyanobacteria have been of great interest because of their potential to generate and release biological toxins, especially, lethal microcystins (MCs). The overall goal of this study was to develop a new sustainable approach to decompose MCs, preferably on-site and in real-time with minimal effort, fewer chemicals, and low energy inputs. To achieve the goal, a high efficiency nitrogen-doped TiO2 photocatalytic film immobilized onto a glass substrate was fabricated via integrated sol-gel synthesis employing nitrogen-containing surfactants as pore-templating agent and nitrogen-dopant. The film exhibited visible light-activated, nanoporous, and transparent properties. Effects of surfactant type, calcination temperature, coating layers, and reaction pH on the photocatalytic decomposition of microcystin-LR (MC-LR) were investigated under visible light. Eventually, the TiO2 film was able to successfully decompose MC-LR on-site in a lake under solar radiation in real-time. This study implies the high potential of the TiO2 film for on-site and real-time decomposition of many organic contaminants in water by using sustainable solar energy.

A photoactive bimetallic CuAg@g-C3N4 catalyst system has been designed and synthesized by impregnating copper and silver nanoparticles over the graphitic carbon nitride surface. Its application has been demonstrated in the hydroxylation of benzene under visible light.

Organochlorine pesticides (OCPs) are toxic and the most potent endocrine disrupting chemicals in the environment. Most OCPs are resistant towards oxidation by OH due to presence of electron-withdrawing chlorine group in their molecular structures. Here, we investigated a visible and simulated solar light-assisted sulfur doped TiO2 (S-TiO2)/peroxymonosulfate (HSO5−) process to eliminate a selected OCP, lindane. Initially, visible and simulated solar light-assisted S-TiO2 photocatalysis resulted in 31.0 and 63.4% removal of lindane (C0 = 1.0 μM), respectively in 6 h. The photocatalytic activity of S-TiO2 was dramatically increased in the presence of 0.2 mM HSO5−, leading to 68.2 and 99.9% lindane removal under visible and simulated solar light illumination, respectively in 6 h. The observed pseudo first-order rate constant for simulated solar light-assisted S-TiO2/HSO5− decreased with increasing initial concentration of lindane, corresponding to 8.98 × 10−1, 6.58 × 10−1 and 3.84 × 10−1 h−1 at [lindane]0 of 0.5, 1.0 and 2.0 μM, respectively. The degradation kinetics were significantly affected by solution pH, leading to 88.2, 99.9 and 71.4% removal of lindane in 6 h at pH 4.0, 5.8 and 8.0, respectively. S-TiO2 film exhibited a high mechanical strength with only 3.3% loss of efficiency after four repeated cycles. Based on the detected reaction intermediates, a possible reaction mechanism was proposed, suggesting dechlorination, dehydrogenation, and hydroxylation via OH, SO4 − and O2 − attack. The results suggest that visible and simulated solar light-assisted S-TiO2/HSO5− is a promising alternative for treatment of water contaminated with most OCPs.

Nanomaterials have been extensively studied for heavy metal ions and dye removals from wastewater. This article reviews the role of nanomaterials as effective adsorbents for wastewater purification. In recent years, numerous novel nanomaterial adsorbents have been developed for enhancing the efficiency and adsorption capacities of removing contaminants from wastewater. The innovation, forthcoming development, and challenges of cost-effective and environmentally acceptable nanomaterials for water purification are discussed and reviewed in this article. This review concludes that nanomaterials have many unique morphological and structural properties that qualify them to be used as effective adsorbents to solve several environmental problems.

In efforts to develop lead anti-TB compounds, a novel series of 19 pyrrolyl benzohydrazides were synthesized and screened to target enoyl-ACP reductase enzyme, which is one of the important enzymes involved in type II fatty acid biosynthetic pathway of M. tuberculosis. Pharmacophores were constructed using GALAHAD to generate alignment of data sets and calculated by Pareto ranking. The pharmacophore features were then filtered by Surflex-dock study using enoyl ACP reductase from M. tuberculosis. Compounds 5b and 5d showed H-bonding interactions with Tyr158, Thr196 and co-factor NAD+ that fitted well within the binding pocket of InhA. All the synthesized compounds were screened for preliminary antibacterial activities against Gram-positive S. aureus and Gram-negative E. coli and M. tuberculosis H37Rv to evaluate their antitubercular activities. Some representative compounds were further tested for mammalian cell toxicity using human lung cancer cell-line (A549) that was found to be nontoxic. These compounds exhibited moderate inhibition activities against InhA.

Fenton processes are promising wastewater treatment alternatives for bio-recalcitrant compounds. Three different methods (i.e., reverse microemulsion, sol-gel, and combustion) were designed to synthesize environmentally friendly ferrites as magnetically recoverable catalysts to be applied for the decomposition of two pharmaceuticals (ciprofloxacin and carbamazepine) that are frequently detected in water bodies. The catalysts were used in a heterogeneous solar photo-Fenton treatment to save the cost of applying high-energy UV radiation sources, and was performed under a slightly basic pH to avoid metal leaching and adding salts for pH adjustment. All the developed catalysts resulted in the effective treatment of ciprofloxacin and carbamazepine in both synthetic and real domestic wastewater. In particular, the sol-gel synthesized ferrite was more magnetic and more suitable for reuse. The degradation pathways of both compounds were elucidated for this treatment. The degradation of ciprofloxacin involved attacks to the quinolone and piperazine rings. The degradation pathway of carbamazepine involved the formation of hydroxyl carbamazepine and dihydroxy carbamazepine before yielding acridine by hydrogen abstraction, decarboxylation, and amine cleavage, which would be further oxidized.

The potential emerging pollutants (PEPs) such as hazardous chemicals, toxic metals, bio-wastes, etc., pose a severe threat to human health, hygiene and ecology by way of polluting the environment and water sources. The PEPs are originated from various industrial effluent discharges including pharmaceutical, food and metal processing industries. These PEPs in contact with water may pollute the water and disturb the aquatic life. Innumerable methods have been used for the treatment of effluents and separating the toxic chemicals/metals. Of these methods, membrane-based separation processes (MBSPs) are effective over the conventional techniques for providing clean water from wastewater streams at an affordable cost with minimum energy requirement. Microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), reverse osmosis (RO), and forward osmosis (FO) methods as well as hybrid technologies are discussed citing the published results of the past decade.

In recent years, various facile and low-cost methods have been developed for the synthesis of advanced nanostructured photocatalytic materials. These catalysts are required to mitigate the energy crisis, environmental deterioration, including water and air pollution. Among the various semiconductors explored, recently novel classes of polymeric graphitic carbon nitride (g-C

Copper doped‐TiO2 (P25) nanomaterials have been intensively studied as promising catalysts for H2 production by photo‐reforming of selected organic compounds. However, the role of copper oxidation states on the improvement of photocatalytic activity is still debated. In this work, CuOx‐impregnated P25‐TiO2 catalysts were used for photocatalytic production of hydrogen from methanol. Copper species/oxidation states both in the as‐prepared catalysts and after the photocatalytic process were investigated. To this purpose, H2 production rates were correlated to physico‐chemical properties of the samples, both before and after photocatalytic process, by means of Raman, X‐Ray Diffraction, Electron Paramagnetic Resonance spectroscopy, X‐Ray Photoelectron Spectroscopy, Temperature‐Programmed Reduction and High Resolution Transmission Electron Microscope techniques. Results revealed the presence of both Cu2O and CuO deposits on the samples surface after calcination. Notably, under near‐UV irradiation, the fraction of highly dispersed CuO particles undergo a partial dissolution process, followed by reduction to metallic copper Cu(s) by photogenerated electrons, boosting H2 production rate. Our findings indicate that both Cu2O and Cu(s) act as co‐catalysts for H2 generation, yet by different mechanisms. Overall this study, provides the basis to enhance catalytic performance of red‐ox active systems through UV‐irradiation approach.

Significant research has been conducted on copper corrosion and solubility in drinking water, including the establishment of the “cupric hydroxide model”. The model describes the temporal aging and associated solubility changes of copper minerals beginning with the most soluble solid, cupric hydroxide. Although the model explains copper levels in field observations well, there are aspects of the model that are not well understood, including a lack of evidence of the presence of cupric hydroxide in drinking water distribution systems. This study aimed to understand the effect of water chemistry on the solubility and properties of newly precipitated cupric solids, including mineral identification. Bench-scale copper precipitation tests were performed in water under a matrix of pH and dissolved inorganic carbon conditions. Copper solids were analyzed using a combination of materials analysis tools including XRD, FT-IR, TGA, and inorganic carbon analyses. Copper solids were X-ray amorphous, isotropic, and were light blue to blue. Based on repeated analysis, georgeite (Cu(2)(CO(3))(OH)(2)·6H(2)O) was conclusively identified as the solid at all test conditions. Georgeite is an extremely rare, amorphous malachite analog, and because of its rarity, very little has been reported on its presence in any environment.

Substituted phenylthiazolyl benzamide and pyrrolyl benzamide derivatives were developed using molecular hybridization technique to create novel lead antimycobacterial molecules used to fight against Mycobacteriumtuberculosis. The newly synthesized molecules have inhibited InhA, the enoyl-ACP reductase enzyme from the mycobacterial type II fatty acid biosynthetic pathway. Of these, compound 3b showed H-bonding interactions with Tyr158 and co-factor NAD+ that binds the active site of InhA. All the molecules were screened for in vitro antitubercular activity against M. tuberculosis H37Rv, as well as some representative molecules as the inhibitors of InhA. Thirteen compounds exhibited good anti-TB activities (MIC = 1.6 μg/mL), but only few representative molecules showed the moderate InhA enzyme inhibition activity.

Alcohols are the essential chemicals used in a variety of pharmaceutical and chemical industries. The extreme purity of alcohols in many of such industrial applications is essential. Though distillation is one of the methods used conventionally to purify alcohols, the method consumes more energy and requires carcinogenic entertainers, making the process environmentally toxic. Alternatively, efforts have been made to focus research efforts on alcohol dehydration by the pervaporation (PV) separation technique using polymeric membranes. The present review is focused on alcohol dehydration using PV separation technique, which is the most efficient and benign method of purifying alcohols that are required in fine chemicals synthesis and developing pharmaceutical formulations. This review will discuss about the latest developments in the area of PV technique used in alcohol dehydration using a variety of novel membranes.

Phosphorus is an essential and limited nutrient that is supplied by a depleting resource, mineral phosphate rock. Eutrophication is occurring in many water bodies which provides an opportunity to recover this nutrient from the water. One method of recovery is through adsorption; this study focused on fabricating a porous and granular adsorptive material for the removal and recovery of phosphate. Magnesium carbonate was combined with cellulose in varying weight ratios (0, 5, 10, 15, 20%) to synthesize pellets, which were then calcined to increase internal surface area. Physiochemical properties such as surface area, surface morphology, elemental composition, and crystal structure of the materials were characterized using Brunauer, Emmett, and Teller (BET) surface area analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The pellet proved to be uniform in composition and an increase in BET surface area correlated with an increase in cellulose content until pellet stability was lost. Phosphate adsorption using the pellets was studied via batch kinetics and sorption isotherms. The pseudo-second-order kinetics model fits best suggesting that the adsorption occurring was chemisorption. The isotherm model that fit best was the Langmuir isotherm, which showed that the maximum equilibrium adsorption capacity increased with an increase in cellulose content between 10% and 20%. The average adsorption capacity achieved in the triplicate isotherm study was 96.4 mg g(−1) for pellets synthesized with 15% cellulose. Overall, using cellulose and subsequent calcination created an additional internal surface area for adsorption of phosphate and suggested that granular materials can be modified for efficient removal and recovery of phosphate from water.

An organic sulfonated graphitic carbon nitride is synthesized and its application has been demonstrated in the conversion of carbohydrates into furanics and related value-added products. The most important feature of the material is the stability and acidity, which could be utilized at elevated temperatures for cleaving carbohydrates and converting them into biologically important scaffolds and platform chemicals.

Microplastics (MPs) with sizes < 5 mm are found in various compositions, shapes, morphologies, and textures that are the major sources of environmental pollution. The fraction of MPs in total weight of plastic accumulation around the world is predicted to be 13.2% by 2060. These micron-sized MPs are hazardous to marine species, birds, animals, soil creatures and humans due to their occurrence in air, water, soil, indoor dust and food items. The present review covers discussions on the damaging effects of MPs on the environment and their removal techniques including biodegradation, adsorption, catalytic, photocatalytic degradation, coagulation, filtration and electro-coagulation. The main techniques used to analyze the structural and surface changes such as cracks, holes and erosion post the degradation processes are FTIR and SEM analysis. In addition, reduction in plastic molecular weight by the microbes implies disintegration of MPs. Adsorptive removal by the magnetic adsorbent promises complete elimination while the biodegradable catalysts could remove 70–100% of MPs. Catalytic degradation via advanced oxidation assisted by [Formula: see text] or [Formula: see text] radicals generated by peroxymonosulfate or sodium sulfate are also adequately covered in addition to photocatalysis. The chemical methods such as sol–gel, agglomeration, and coagulation in conjunction with other physical methods are discussed concerning the drinking water/wastewater/sludge treatments. The efficacy, merits and demerits of the currently used removal approaches are reviewed that will be helpful in developing more sophisticated technologies for the complete mitigation of MPs from the environment.

Nanomaterials (NMs), both natural and synthetic, are produced, transformed, and exported into our environment daily. Natural NMs annual flux to the environment is around 97% of the total and is significantly higher than synthetic NMs. However, synthetic NMs are considered to have a detrimental effect on the environment. The extensive usage of synthetic NMs in different fields, including chemical, engineering, electronics, and medicine, makes them susceptible to be discharged into the atmosphere, various water sources, soil, and landfill waste. As ever-larger quantities of NMs end up in our environment and start interacting with the biota, it is crucial to understand their behavior under various environmental conditions, their exposure pathway, and their health effects on human beings. This review paper comprises a large portion of the latest research on NMs and the environment. The article describes the natural and synthetic NMs, covering both incidental and engineered NMs and their behavior in the natural environment. The review includes a brief discussion on sampling strategies and various analytical tools to study NMs in complex environmental matrices. The interaction of NMs in natural environments and their pathway to human exposure has been summarized. The potential of NMs to impact human health has been elaborated. The nanotoxicological effect of NMs based on their inherent properties concerning to human health is also reviewed. The knowledge gaps and future research needs on NMs are reported. The findings in this paper will be a resource for researchers working on NMs all over the world to understand better the challenges associated with NMs in the natural environment and their human health effects.

A novel microwave (MW)-based method was developed for in-situ cross-linking/polymerization of polyacrylic acid (PAA) onto hydrophilic polyvinylidene fluoride (PVDF) membrane for preparation of PVDFMW catalytic-membrane system. Unlike traditional thermal techniques, the use of MW radiation provided faster PAA polymerization and synthesis of PVDFMW membranes with excellent mechanical stability and high permeability. Air cooling and the dose-wise application of MW were the most influential parameters on the quality of PAA grafting and on the physical properties of PVDFMW membranes. Detailed surface characterization of PVDFMW revealed pores of the upper surface were occupied with PAA molecules. Nano zero-valent-iron (nZVI)-decorated PVDFMW membranes (nZVI-PVDFMW) were prepared and their catalytic activities were tested for the degradation of bisphenol A (BPA) in a cross-flow system. The nZVI-PVDFMW system demonstrated 52% ± 0.5 of BPA removal under low permeate flux (50 L/m2. h) in the presence of 10 mM of H2O2. The current study demonstrated MW is an advantageous technique for the preparation of composite membranes with ultra-fine morphology and improved physical properties for use in water treatment applications.

The current study investigates a novel redox technology based on synthetic franklinite-like zinc-ferrite nanomaterial with magnetic properties and redox nature for potential use in water treatment. Physicochemical characterization revealed the nanoscale size and AB(2)O(4) spinel configuration of the zinc-ferrite nanomaterial. The redox activity of nanoparticles was tested for degradation of diclofenac (DCF) pharmaceutical in water, without any added external oxidants and under dark experimental conditions. Results revealed ~90% degradation in DCF (10 μM) within 2 min of reaction using 0.17 g/L Zn(1.0)Fe(2.0)O(4). Degradation of DCF was due to chemical reduction by surface electrons on zinc-ferrite and oxidation by oxygen-based radicals. Three byproducts from reduction route and eight from oxidation pathways were identified in the reaction system. Reaction pathways were suggested based on the identified byproducts. Results demonstrated the magnetic zinc-ferrite is a standalone technology that has a great promise for rapid degradation of organic contaminants, such as DCF in water.

A novel magnetically recoverable, visible light active TiO2-WO3 composite (Fe3O4@SiO2@TiO2-WO3) was prepared to enable the photocatalyst recovery after the degradation of bisphenol A (BPA) under simulated solar light. For comparison, the photocatalytic activity of other materials such as non-magnetic TiO2-WO3, Fe3O4@SiO2@TiO2, TiO2, and the commercial TiO2 P25 was also evaluated under the studied experimental conditions. The structure and morphology of the synthesized materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), and electron dispersion spectroscopy (EDS). Moreover, Brunauer-Emmett-Teller (BET) surface area and magnetic properties of the samples were determined. The Fe3O4@SiO2@TiO2-WO3 and TiO2-WO3 led to a BPA degradation of 17.50 and 27.92 %, respectively, after 2 h of the simulated solar light irradiation. Even though their activity was lower than that of P25, which degraded completely BPA after 1 h, our catalysts were magnetically separable for their further reuse in the treatment. Furthermore, the influence of the water matrix in the photocatalytic activity of the samples was studied in municipal wastewater. Finally, the identification of reaction intermediates was performed and a possible BPA degradation pathway was proposed to provide a better understanding of the degradation process.

The relationship between microbe populations that are active on engineered-product surfaces and their relationship to surface corrosion or human health is increasingly being recognized by the materials engineering community as a critically important study-direction. Microbial contamination from biofilms and germ colonies leads to costs that are reported to be extremely high every year in infection control, epidemics, corrosion loss and energy/infrastructure materials loss throughout the world. Nanostructured surfaces, particularly those that are hard-surface nanoporous (pore radii between 2 and 1000 nm), are an emerging class of surfaces that have recently been recognized as important for the prevention of microbial colony growth and biofilm formation. Such nanostructured/nanoporous surfaces, whether made with deposited nanoparticles (welded nanoparticles), or formed by ion-assisted growth on a surface have been found to display biocidal activity with varying efficacy that depends on both the microbe and the nanosurface features. The rate of mortality from common pathogens that are resident in ubiquitous bio-films when attached to common engineering surfaces made of steels, titanium and zirconium appears to be increasing. In this short review, we look at methods of manufacture of durable (i.e., highly scratch resistant) nanostructuring on commonly used engineering surfaces. The microstructures, energy dispersive X-ray analysis, X-ray photo-electron spectroscopy and other types of characterization of a few such surfaces are presented. Simple tests are required by the surface engineering community for understanding the efficacy of a surface for antimicrobial action. These are reviewed. The surface drying rate and the dynamics of the droplet spread have been proposed in the literature as quick methods that correlate well with the residual antimicrobial activity efficacy even after some surface abrasion of the nanostructured surface. A categorization of a surface against short-term antimicrobial action and long-term action is proposed in this review article. Test periods that span time-frames greater than 5 years have demonstrated a high efficacy of the nanoporous nanostructures for preventing bio-film formation. New comparative results for diamond- and graphite-containing surfaces are presented. A brief discussion on a recently developed plasma application technique for creating durable nanoporous surfaces is presented. Although considerable information is now available regarding tunable surface nanofeatures for antimicroabial efficacy, there is a need for more research activity, particularly directed toward the low cost manufacture and rapid characterization of durable (wear and chemical resistant) surfaces that display permanent antimicrobial behavior.