Incorporation of Cu5FeS4 QDs with Abundant Oxygen Vacancy TiO2 QDs/TiO2 OVs: Double S-Scheme Photocatalysts for Effectual N2 Conversion to NH3 under Simulated Solar Light.

Photocatalytic N2 conversion to NH3 is a green, sustainable pathway with renewable energy sources and carbon neutrality. In this research, ternary TiO2 QDs/TiO2 OVs/Cu5FeS4 nanocomposites were prepared by an easy and affordable procedure and utilized to produce clean ammonia energy without a sacrificial agent. The amount of produced green ammonia by the optimum nanocomposite achieved was 17,274 µmol L-1 g-1, which was approximately 20.9, 6.48, 4.45, 2.26, and 1.45 times higher than those of commercial TiO2, TiO2 QDs, TiO2 OVs, Cu5FeS4, and TiO2 QDs/TiO2 OVs photocatalysts, respectively. Lattice compatibility through the developed homojunction within TiO2 QDs/TiO2 OVs and the integration of Cu5FeS4 nanoparticles led to the establishment of a double S-scheme homo/heterojunction system, which improved the photocatalytic activity by maintaining electrons and holes with high oxidation and reduction power and greatly reduced the recombination of charges, which led to the acceleration of charge transfer and migration. Besides, the promoted surface area compared to the pure components, introducing oxygen vacancies, and reducing the particle size boosted the photocatalytic N2 conversion to NH3. The results of this research are a basis for the rational design of homojunction/heterojunction visible-light-responsive systems for photocatalytic nitrogen fixation reactions.

Decoration of Carbon Dots on Oxygen-Vacancy-Enriched S-Scheme TiO2 Quantum Dots/TiO2 Oxygen Vacancies Photocatalysts: Impressive Quantum-Dot-Sized Photocatalysts for Remediation of Antibiotics, Bacteria, and Dyes.

Today, cleaning the environment using photocatalytic technology is one of the main research activities. In this study, carbon dots (C-dots) were anchored on oxygen-vacancy-enriched TiO2 quantum dots (QDs)/TiO2 oxygen vacancies (OVs) using a facile procedure. The resultant ternary TiO2 QDs/TiO2 OVs/C-dots photocatalysts with a quantum dot size of almost 4.55 nm were used for detoxification of aqueous solutions containing four antibiotics and three organic dyes as well as inactivation of two pathogenic bacteria, including Escherichia coli and Staphylococcus aureus, upon visible light. The degradation constant of tetracycline over the optimized TiO2 QDs/TiO2 OVs/C-dots nanocomposite reached 714 × 10-4 min-1, which was 17.3, 12.1, and 2.92 times higher than TiO2 QDs, TiO2 OVs, and TQDs/TOVs (1:1) materials, respectively. Effective separation of electron-hole pairs between TiO2 QDs and TiO2 OVs counterparts through decorated C-dots by an established S-scheme system was the main reason for boosted photocatalytic activity. With regard to the facile growth of wheat and lentil seeds in the treated solutions, it is hoped that the TiO2 QDs/TiO2 OVs/C-dots nanocomposite with significant stability could be used to clean up wastewaters.

Floating photocatalysts as promising materials for environmental detoxification and energy production: A review.

The oxygenation process of the catalyst surface, the incident-light harvesting capability, and facile recycling of utilized photocatalysts play key role in the outstanding photocatalytic performances. The typical existing photocatalysts in powder form have many drawbacks, such as difficult separation from the treated water, insufficient surface oxygenation, poor active surface area, low incident-light harvesting ability, and secondary pollution of the environment. A great number of scientific works introduced novel and fresh ideas related to designing floating photocatalytic systems by immobilizing highly active photocatalysts onto a floatable substrate. Thanks to direct contact with the illuminated light and oxygen molecules in the interface of water/air, the photocatalytic performance is maximized through production of more reactive species, employed in the photocatalytic reactions. Furthermore, facile recovering of the utilized photocatalysts for next processes avoids secondary pollution as well as diminishes the process's price. This review highlights the performance of developed floating photocatalysts for diverse applications. Furthermore, different floating substrates and possible mechanisms in floating photocatalysts are briefly mentioned. In addition, several emerging self-floating photocatalytic systems are taken attention and discussed. Specially, coupling photo-thermal and photocatalytic effects seems to be a good strategy for introducing a new class of floating photocatalyst to utilize the free, abundant, and green sunlight energy for the aims of water desalination and purification. Despite of a large number of attempts about the floating photocatalysts, there are still plenty of rooms for more in-depth research to be carried out for attaining the required characteristics of the large scale utilizations of these materials.

Modification of PAN electrospun nanofiber membranes with g-C3N4 nanotubes/carbon dots to enhance MBR performance.

This study is dedicated to the enhancement of electrospun polyacrylonitrile (PAN) nanofiber membranes for their application in membrane bioreactor (MBR) processes. The improvement is achieved through the incorporation of graphitic carbon nitride nanotubes/carbon dots (g-C3N4 NT/CDs) and subsequent heat post-treatments at varying temperatures. Notably, the hot-pressing methodology effectively mitigates surface roughness and significantly reduces issues related to peeling during nanofiber experimentation. Our results demonstrate that the introduction of 0.5 wt% of g-C3N4 NT/CDs leads to a substantial enhancement in water flux. In particular, nanocomposite membranes subjected to hot-pressing at 90 °C for 10 min exhibited an impressive flux recovery ratio (FRR) of 70%. Furthermore, the heat-treated nanocomposite membranes exhibited remarkable antifouling properties and significantly reduced fouling rates when compared to their heat-treated bare counterparts. This study underscores the noteworthy potential of g-C3N4 NT/CDs-modified PAN nanofiber membranes to substantially elevate MBR performance, firmly positioning them as highly promising candidates for critical applications in the domains of water and wastewater treatment. However, it is imperative to underscore that the existing written material necessitates a comprehensive overhaul to align with the provided structural framework.

Oxygen vacancy-rich CeO2 decorated with Cu3BiS3 nanoparticles: Outstanding visible-light photocatalytic performance towards tetracycline degradation.

Recently, the degradation of antibiotics has attracted a lot of attention all over the world, because the accumulation of these recalcitrant compounds in the environment, and their entry into the food chain have severely affected on human health. Herein, oxygen vacancy-rich CeO2 was decorated with Cu3BiS3 nanoparticles to fabricate Z-scheme CeO2-x/Cu3BiS3 photocatalysts with a simple procedure. Intriguingly, photocatalytic ability of CeO2-x/Cu3BiS3 (30%) nanocomposite in the detoxification of tetracycline hydrochloride, cephalexin, azithromycin, and rhodamine B was elevated 31.3, 28.2, 45.2, and 10.1-folds as much as CeO2, and 5.19, 5.97, 32.2, and 4.69-folds compared with the CeO2-x photocatalyst, respectively. The admirable activity of CeO2-x/Cu3BiS3 (30%) nanocomposite was ascribed to the production of many charge carriers, efficacious segregation and transfer of charges, and improved textural features, which were confirmed by UV-vis DRS, EIS, photocurrent density, PL, and BET analyses. In addition, the TC degradation pathway was investigated with LC-MS analysis, and also the biocompatibility of the purified solution was displayed with wheat seed cultivation. Regarding outstanding activity and facile synthesis, the CeO2-x/Cu3BiS3 (30%) photocatalyst could be utilized for wastewater treatment.

Preparation of TiO2/Fe-MOF n‒n heterojunction photocatalysts for visible-light degradation of tetracycline hydrochloride.

Visible-light-assisted photocatalysis has been recognized as an effective solution to the degradation of various pollutants including antibiotics, pesticides, herbicides, microplastics, and organic dyes. Herein, an n-n heterojunction TiO2/Fe-MOF photocatalyst is reported, designed via solvothermal synthesis route. TiO2/Fe-MOF photocatalyst was characterized by XPS, BET, EIS, EDS, DRS, PL, FTIR, XRD, TEM, SEM and HRTEM techniques. Inspired by XRD, FTIR, XPS, EDS, TEM, SEM, and HRTEM analyses, the successful synthesis of n-n heterojunction TiO2/Fe-MOF photocatalysts was proved. The migration efficiency of the light-induced electron-hole pairs was confirmed by the PL and EIS tests. TiO2/Fe-MOF exhibited a significant performance for tetracycline hydrochloride (TC) removal under visible light irradiation. TC removal efficiency for TiO2/Fe-MOF (15%) nanocomposite reached 97% within 240 min, ca. 11 times higher than pure TiO2. The photocatalytic enhancement of TiO2/Fe-MOF could be attributed to the broadening the light response range, forming an n-n junction between Fe-MOF and TiO2 components, suppressing charge recombination. Based on recycling experiments, TiO2/Fe-MOF had a good potential to be used in consecutive TC degradation tests.

Retraction: Polyethylene glycol-doped BiZn2VO6 as a high-efficiency solar-light-activated photocatalyst with substantial durability toward photodegradation of organic contaminations.

[This retracts the article DOI: 10.1039/C8RA06896H.].

Outstanding photocatalytic nitrogen fixation performance of TiO2 QDs modified by Bi2O3/NaBiS2 nanostructures upon simulated sunlight.

Nowadays, a promising material for NH3 production under mild and safe conditions using heterogeneous photocatalysts is very important. In this regard, Bi2O3 and NaBiS2 nanoparticles were combined with TiO2 quantum dots (QDs) through a facile hydrothermal process. The TiO2 QDs/Bi2O3/NaBiS2 nanocomposites displayed excellent performance in the photofixation of nitrogen upon simulated sunlight. The NH3 generation rate constant over the optimum nanocomposite was 10.2 and 3.3-folds higher than TiO2 (P25) and TiO2 QDs photocatalysts, respectively. The spectroscopic and electrochemical studies affirmed more effective segregation and transfer of photo-induced charge carriers within ternary nanocomposite, due to the developing tandem n-n-p heterojunctions, which led to more lifetime of charges. Moreover, the impacts of solvent, pH, electron scavenger, and lake of nitrogen molecules on the NH3 generation were investigated. Finally, it was concluded that the TiO2 QDs/Bi2O3/NaBiS2 nanocomposite, with appealing features of more activity, high stability, and a facile one-pot synthesis method, is a promising photocatalyst in nitrogen fixation technology.

N-doped graphene for electrocatalytic O2 and CO2 reduction.

The electrocatalytic CO2 reduction reaction (CO2RR) and oxygen reduction reaction (ORR) are important approaches to realize energy conversion and sustainable development. However, sluggish reaction kinetics severely hinders the practical application of devices related to these reactions. N-doped graphene (NG) with unique properties exhibits great potential in catalyzing the CO2RR and ORR, which is attributed to the electron redistribution. In this review, we start from the fundamental properties of NG, especially emphasizing the changes caused by N doping. Then the synthetic methods are summarized by classifying them into top-down strategies and bottom-up strategies. Subsequently, the applications of NG in the ORR and CO2RR are discussed and the effects of electronic structure on the electrocatalytic activity are highlighted. Finally, we give our own perspective on the future research direction of NG in the applications of the ORR and CO2RR.

Design of TiO2/Ag3BiO3 n-n heterojunction for enhanced degradation of tetracycline hydrochloride under visible-light irradiation.

Pharmaceutical residual contaminants in aquatic ecosystems have caused severe risks to human health. Affordable, eco-friendly and effective photocatalysts to deal with these pollutants has become a hot topic in the scientific community. In this research, Ag3BiO3 nanoparticles were embedded on TiO2 to form n-n heterojunction through a facile hydrothermal method. According to scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FT-IR), brunauer emmett teller (BET), electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), photoluminescence (PL), X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV-vis diffuse reflectance spectroscopy (UV-vis DRS) tests, the successful construction of TiO2/Ag3BiO3 heterojunction is proved. TiO2/Ag3BiO3 heterojunctions were employed as photocatalysts to remove tetracycline hydrochloride (TCH) under visible light irradiation in aqueous solution. Optimum TCH photodegradation efficiency was observed for TiO2/Ag3BiO3 (10%), 15.4 times superior to that of TiO2. The enhanced TCH photodegradation efficiency of TiO2/Ag3BiO3 results from improved light absorption capacity and the reduction of recombination of photogenerated charge carriers via generation of n-n heterojunctions. The mechanism of increasing the photodegradation efficiency of TCH was determined by employing reactive species quenching experiments. TiO2/Ag3BiO3 (10%) also exhibited an acceptable stability.

Antifungal Activities of Pure and ZnO-Encapsulated Essential Oil of Zataria multiflora on Alternaria solani as the Pathogenic Agent of Tomato Early Blight Disease.

The utilization of plant essential oils (EOs) and nanomaterials due to their safety compared with synthetic chemicals has been considered in the management of plant diseases. In this study, the inhibitory effects of Zataria multiflora, Nepeta haussknechtii, Artemisia sieberi, and Citrus aurantifolia EOs in pure and Zinc Oxide (ZnO) nanocapsulated formulations were evaluated on the mycelial growth of Alternaria solani to find a suitable alternative for synthetic chemicals. The crystal structure and morphological properties of the fabricated nanomaterials were assessed via X-ray diffraction (XRD) and scanning electron microscope (SEM) analyses. The textural features of the prepared nanoparticles were investigated with Brunauer-Emmett-Teller (BET) analysis, and the presence of elements in the samples was studied with energy-dispersive X-ray (EDX) technique. The mycelial growth inhibitory (MGI) was performed in the laboratory by mixing with potato dextrose agar (PDA) medium at concentrations of 100, 300, 600, 1,000, 1,500, and 2,000 ppm. Based on the results, major differences were monitored between different concentrations. At the highest studied concentration, the inhibition of Z. multiflora EO was 100%, which was 43.20, 42.37, and 21.19% for N. haussknechtii, A. sieberi, and C. aurantifolia, respectively, and the inhibition of their nanocapsules was 100, 51.32, 55.23, and 26.58%, respectively. In the greenhouse study, Z. multiflora EO and its nanocapsule (ZnO-ZmEO) were compared with the ZnO and chlorothalonil fungicide based on the highest inhibitory of Z. multiflora in vitro. The highest antifungal effect was related to the ZnO-ZmEO by 53.33%. Therefore, the ZnO-ZmEO formulation can be recommended as a biofungicide for managing and controlling tomato early blight disease after further research.

Nanoarchitecturing TiO2/NiCr2O4 p-n heterojunction photocatalysts for visible-light-induced activation of persulfate to remove tetracycline hydrochloride.

Herein, TiO2/NiCr2O4 nanocomposites with p-n heterojunctions were synthesized via a refluxing method and used with peroxydisulfate (PDS) to produce extensive reactive radicals. Textural, optical, photoelectrochemical, structural, and morphological properties of the prepared materials were extensively investigated. After adding 1.48 mM PDS, the removal rate constant of tetracycline hydrochloride (TH) over the TiO2/NiCr2O4 (20%)/PDS system was almost 20.5, 7.24, and 5.91-times as high as the pristine TiO2, TiO2/PDS, and TiO2/NiCr2O4 (20%) samples, respectively. Therefore, the synergistic effect of PDS and heterogeneous photocatalysis remarkably impacted the degradation reaction of TH. It was proposed that all h+, •O2-, •OH, and SO4•- contributed to the degradation reaction. According to the formation of heterojunction between n-TiO2, and p-NiCr2O4 semiconductors, a plausible mechanism for removal of different contaminants in the TiO2/NiCr2O4/PDS system was discussed.

Ultrasonic-assisted decoration of Ag2WO4, AgI, and Ag nanoparticles over tubular g-C3N4: Plasmonic photocatalysts for impressive removal of tetracycline under visible light.

The development of an efficient, eco-friendly, and low-cost photocatalyst is essential for addressing environmental and energy crises. In this regard, we report novel plasmonic photocatalysts through adorning tubular g-C3N4 with Ag2WO4, Ag, and AgI nanoparticles (TGCN/Ag/Ag2WO4/AgI) fabricated via a facile ultrasonic-irradiation procedure. The TGCN/Ag/Ag2WO4/AgI (20%) nanocomposite presented the excellent photocatalytic ability for removal of tetracycline hydrochloride under visible light, which was almost 45.6, 4.03, and 1.32 times more than GCN, TGCN, and TGCN/Ag/Ag2WO4 (20%) photocatalysts, respectively. Interestingly, the photocatalyst displayed impressive ability for the degradations of amoxicilline, rhodamine B, methyl orange, fuchsine, and methylene blue, which was 14.7, 52.2, 9.8, 13.2, and 7.46 times as much as pure GCN. The outcomes of DRS, PL, EIS, and photocurrent density analyses proved that the impressive activity could be related to the highly promoted harvesting of visible light, segregation of charge carriers, and improved charge migrations. In addition, trapping tests exhibited that •O2- and h+ were active species in the photocatalysis process.

Antifungal activity of TiO2/AgBr nanocomposites on some phytopathogenic fungi.

TiO2/AgBr composites were synthesized by a simple ultrasonic strategy. Various instruments such as SEM, EDX, XRD, and FT-IR were exploited to investigate their characteristics. Antifungal activities of the as-obtained samples were assessed through the inactivation of Fusarium graminearum in the spore suspension method and mycelial growth inhibition of F. graminearum, Botrytis cinerea, and Sclerotinia sclerotiorum in the microdilution method. The results represented that the TiO2/AgBr samples possess higher antifungal activities on F. graminearum spores than the pure TiO2. The sample with 20 wt% silver bromide represented the highest inhibitory effect on the growth of F. graminearum so that all fungal spores were degraded in the initial times of the treatment process. The inactivation of fungal spores after 60 min was 35.2%, 97.8%, 98.9%, and 98.7%, in respect, for 5, 10, 20, and 30 weight percent of AgBr in the binary nanocomposites, while the inhibition rate was 13.4% for the pure TiO2. With increasing ultrasound irradiation time for more than 30 min, the inactivation rate constant decreased. It was also found that the antifungal activity of the nanocomposites without calcination was higher than those of the calcined materials. Considering the antifungal potential against phytopathogenic fungi and advantages such as simple synthesis and eco-friendly nature, it seems that TiO2/AgBr nanocomposites can be used instead of synthetic chemicals after additional field investigations and mass production.

Hydrogen peroxide treated g-C3N4 as an effective hydrophilic nanosheet for modification of polyethersulfone membranes with enhanced permeability and antifouling characteristics.

In this study, first, graphitic carbon nitride was treated with hydrogen peroxide (abbreviated as H2O2-g-C3N4), then was used as a new hydrophilic nanomaterial in the fabrication of polyethersulfone (PES) mixed matrix membrane (MMM) for improving flux, protein and dye separation efficiency and antifouling properties. The H2O2-g-C3N4 nanosheet was inserted into the doping solution to fabricate PES/H2O2-g-C3N4 nanocomposite membrane with the non-solvent induced phase inversion procedure. The results of the SEM and AFM images and also porosity and contact angle analysis were indicated that the modified membranes with H2O2-g-C3N4 had more porosity, smoother surface and more hydrophilic. Also, the influence of various weight percentage of H2O2-g-C3N4 was investigated systematically on the membrane performance. By blending of H2O2-g-C3N4 nanosheet in the membrane matrix, the permeability was raised from 4.1 (for bare membrane) to 30.1 L m-2 h-1 bar-1. Additionally, the effect of the H2O2-g-C3N4 material on the antifouling features indicated that the flux recover ratio of the H2O2-g-C3N4 MMMs was improved and the resistance parameters were reduced. Also, the effect of the H2O2-g-C3N4 material on the antifouling features indicated that the flux recover ratio of the H2O2-g-C3N4 MMMs was improved and the resistance parameters were reduced. Finally, the dye rejection efficiency of the nanocomposite membranes for Orange II and Reactive Yellow 168 was improved. As a result, it could be mentioned that the mixing low amount of H2O2-g-C3N4 in the membrane structure could significantly improve the membrane flux and antifouling properties without reduction in membrane rejection efficiency.

Review on the hazardous applications and photodegradation mechanisms of chlorophenols over different photocatalysts.

Chlorophenols are very important environmental pollutants, which have created huge problems for both aquatic and terrestrial lives. Therefore, their removal needs urgent, effective, and advanced technologies to safeguard our environment for future generation. This review encompasses a comprehensive study of the applications of chlorophenols, their hazardous effects and photocatalytic degradation under light illumination. The effect of various factors such as pH and presence of different anions on the photocatalytic oxidation of chlorophenols have been elaborated comprehensively. The production of different oxidizing agents taking part in the photodegradation of chlorophenols are given a bird eye view. The photocatalytic degradation mechanism of different chlorophenols over various photocatalyts has been discussed in more detail and elaborated that how different photocatalysts degrade the same chlorophenols with the aid of different oxidizing agents produced during photocatalysis. Finally, a future perspective has been given to deal with the effective removal of these hazardous pollutants from the environment.

Correction: Facile preparation of novel quaternary g-C3N4/Fe3O4/AgI/Bi2S3 nanocomposites: magnetically separable visible-light-driven photocatalysts with significantly enhanced activity.

[This corrects the article DOI: 10.1039/C6RA12414C.].

Biologically-synthesised ZnO/CuO/Ag nanocomposite using propolis extract and coated on the gauze for wound healing applications.

Wound healing has long been recognised as a major clinical challenge for which stablishing more effective wound therapies is necessary. The generation of metallic nanocomposites using biological compounds is emerging as a new promising strategy for this purpose. In this study, four metallic nanoparticles (NPs) with propolis extract (Ext) and one without propolis including ZnO/Ext, ZnO/Ag/Ext, ZnO/CuO/Ext, ZnO/Ag/CuO/Ext and ZnO/W were prepared by microwave method and assessed for their wound healing activity on excision experimental model of wounds in rats. The developed nanocomposites have been characterised by physico-chemical methods such as X-ray diffraction, scanning electron microscopy, diffuse reflectance UV-vis spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis and Brunauer-Emmett-Teller analyses. The wounded animals treated with the NPs/Ext in five groups for 18 days. Every 6 days, for measuring wound closure rate, three samples of each group were examined for histopathological analysis. The prepared tissue sections were investigated by haematoxylin and Eosin stainings for the formation of epidermis, dermis and muscular and Masson's trichrome staining for the formation of collagen fibres. These findings toughly support the probability of using this new ZnO/Ag/Ext materials dressing for a wound care performance with significant effect compared to other NPs.

Co-regulative effects of chitosan-fennel seed extract system on the hormonal and biochemical factors involved in the polycystic ovarian syndrome.

There is a renewed interest in the application of chitosan-based drug delivery systems over the last few years. In this study, the ionic gelation method was used to prepare chitosan-engaged tripolyphosphate ions, as the cross-linking molecule, (Chit-TPP) and concurrent loading of the biomolecules of the ethanolic extract of fennel, Foeniculum vulgare, seed (FEC@NBC). The samples were characterized by SEM, DLS, TGA, FTIR, XRD, GC-MS, and zeta potential, and their effects on the related hormonal and biochemical factors of the rats with polycystic ovarian syndrome (PCOS) were assessed. The estradiol valerate-induced PCOS in female rats was confirmed by vaginal smear test and subsequent histological screening. The PCOS-induced rats were treated by fennel seed extract (FSX), Chit-TPP, and FEC@NBC. The process of treatment was monitored by measuring the serum levels of testosterone, luteinizing hormone, follicle-stimulating hormone, insulin, glucose, high-density lipoprotein cholesterol, total cholesterol, and total triglyceride after 16 days of treatment and compared with healthy control and untreated PCOS-control groups. The FEC@NBC administration contributed to the remarkable hormonal, glucose, and lipid profile regulation in the rats with PCOS. The significance of FEC@NBC performance in dealing with PCOS complications compared to that of the only extract could be resulted from the effective targeted delivery and stability of phytomolecules when encapsulated in Chit-TPP.