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As the population increases and manufacturing grows, greenhouse gas and other harmful emissions increase. Contaminated with chemicals such as dyes, pesticides, pharmaceuticals, oil, heavy metals or radionuclides, wastewater purification has become an urgent issue. Various technologies exist that can remove these contaminants from wastewater sources, but they often demand high energy and/or high cost, and in some cases produce contaminant laden sludge that requires safe disposal. The need for methods which are less capital intensive, less operationally costly and more environmentally friendly is suggested. Cellulose-based materials have emerged as promising candidates for wastewater treatment due to their renewability, low cost, biodegradability, hydrophilicity, and antimicrobial property. In this review article, we focussed on developing sustainable and biodegradable cellulose-based materials for wastewater treatment. This article deals with cellulose-based materials’ scope and their conversion into valuable products like hydrogel, aerogel, cellulose composites, and nanocellulose. The cellulose-based materials have no harmful environmental impact and are plentiful. The modified cellulose-based materials applying as membrane, adsorbent, sorbent, and beads to purify the wastewater were discussed. Finally, the challenges and future prospects of cellulose-based materials for wastewater treatment were considered, emphasizing their potential to be sustainable and eco-friendly alternatives to traditional materials used in wastewater treatment.

Desalination brine can negatively impact the marine environment in several ways, although there are ongoing discussions regarding the severity and magnitude of environmental effects. A fascinating strategy to lessen any adverse effects is to undertake resource recovery from the brine, which also has the potential for additional revenue generation. More recently, the increasing demand for secure and less geographically restricted sources of precious or rare earth minerals, integrated with growing awareness of waste management and environmental sustainability, is driving the development of economically viable technologies to recover valuable materials from waste streams. This article provides an overview of different methods and technologies, including reverse osmosis (RO), electrodialysis (ED), and distillation, that can be used to recover precious materials, including Li, Mg, Na, and Rb and valuable blends from various waste sources and thus create a more sustainable and circular economy. The mechanisms are discussed in detail, including electrochemical processes (electrolysis, ED, and capacitive deionization), thermal desalination (multistage flash distillation and membrane distillation), pressure‐driven desalination (RO and nanofiltration), and microbial desalination cells. Challenges associated with recovering precious materials from waste streams, such as fouling, scaling, and environmental impact, along with further research directions and potential applications of desalination technologies, are also addressed.

This study investigates the development of sustainable multifunctional foams utilizing hemp stalk waste, lignin, xylan, pectin, glycerol, and citric acid. Using the freeze-drying method for foam formation in combination with industrial waste products and renewable resources, we emphasize a green, scalable material development approach. In total, 25 distinct formulations were prepared and methodically examined, mainly focusing on the roles of citric acid, pectin, and glycerol. Thermal crosslinking, conducted at 140°C, was analyzed using FTIR, confirming the formation of ester bonds. The microstructural characterization of the foams revealed distinct variations from nanofibrillar to microfibrillar structures based on composition. The bulk density of the foams ranged from 13 to 152 mg/cm3, and porosity values varied from 97 % to 99 % for most of the compositions. Foams showed up to 50 g/g water, 51 g/g rapeseed oil, and 46 g/g kerosine absorption. Foam absorption capacity changes were examined through 10 iterative cycles in water, demonstrating that most compositions retained near-original absorption capacities. Adding glycerol conferred exceptional hydrophobic properties to the foam surfaces, as evidenced by water contact angles ranging between 140° and 150°. The thermal conductivity of foams ranged from 0.040 to 0.046 W/mK. The mechanical properties of foams were assessed using compression testing, which showed highly tunable structures ranging from soft to rigid. This study illustrates the broad applicability of these foams, emphasizing their utility in thermal insulation, filtration systems, and environmental cleanup, among other potential uses.

Abstract Synthetic polymers have shown a great impact on every aspect of our life and attained an exponential rise in their production and utilization in the past decades due to their durability, flexibility, moldability, and inexpensive nature. However, the use of natural polymers or development of safe and environment-friendly synthetic bio-based polymers is continuously undergoing for a sustainable future owing to the exhaustion of petroleum-based resources or fossil-based materials, disposal and economical concerns, including government guidelines. In this regard, the development of new sustainable polymers or materials will step up and build a genuinely circular economy by decreasing manufacture or utilization of fossil-based materials as limited reserves.

Highlights Safer and biodegradable nano/micro-supramolecular biopolymers transform farming practices. Supramolecular biopolymers improve soil structure, water retention, and plant nutrient uptake. Encapsulation of bioactive compounds and their controlled release by nano/micro-supramolecular biopolymers enables targeted delivery. Biopolymer networks can potentially be embedded in biosensors for crop protection goals.

Direct ethanol fuel cells (DEFCs) are better than others in commercially used FCs due to easy availability, less toxicity, and C‐2‐type alcohol. Ethanol has a high theoretical efficiency of 97% and is a safe, plentiful, and renewable resource that can be stored and controlled using the infrastructure that is in place now. Nevertheless, low functional efficiencies and the release of carbon dioxide (CO2), acetaldehyde, and byproducts of acetic acid must be addressed if DEFCs are to grow and become more commercially viable. To overcome these problems, new anode and cathode catalysts are needed, so this review article discusses the introduction of FCs with their structure, working and mechanism. Further, the report covers various types of FC catalysts, and their application in FC technology is explained. The role of the catalyst (such as anode and cathode), similarities and differences between Pt/Pd‐based catalysts, and the importance of supporting materials (such as carbon, transition metal dichalcogenides, MXene, and black phosphorus‐based materials) in DEFCs are described. In addition, the applications, advantages, and disadvantages of the DEFCs are discussed. Finally, the proposed theme is concluded with the existing challenges in this field and the future prospect of DEFCs.

Two novel two-dimensional (2D) supramolecular organic frameworks were fabricated in water based on the encapsulation-enhanced donor-acceptor interaction between the methyl viologen (MV) units, methoxy naphthyl (MN) units, and CB [8]. The tetraphenylethylene (TPE) derivatives 1 with four MV units were employed as rigid building blocks and the two MN units modified oligoethylene glycol derivatives 2 and 3 served as flexible edges, respectively. The obtained two SOFs have obvious sheet-like structures and exhibit fluorescence emission at 350–500 ​nm. In addition, these two SOFs were employed for the luminescent detection of Cr(VI) and Mn(VII) in aqueous solutions, and the detection limits of CrO42−, Cr2O72−, and MnO4− were calculated in a very low concentration range, indicating that these two SOFs can serve as a potential sensor for Cr(VI) and Mn(VII) detection in water. This work constructs two SOFs in an aqueous solution through a facile method and further enriches the applications of SOFs.

Abstract Surface modification is an important approach to modify the properties of materials. Numerous approaches have been adopted to tailor the properties of such materials, which have been proven successful at many scales and parameters. However, most of these techniques are often tedious, poorly adhesive, costly, sometimes hazardous, and surface‐specific, hence cannot be extended on a large scale and all kinds of surfaces. These shortcomings have led to the emergence of new dopamine (DA) based green surface modification technique where a thin polydopamine (PDA) layer is deposited on surfaces through a facile polymerization of DA under alkaline conditions to enable the surface for various applications. This surface modification strategy has several advantages over other techniques in deposition processing under mild conditions, cost‐effective and straightforward ingredients, and applicability to all kinds of surfaces regardless of their sizes, shapes, and types. Moreover, the PDA layer enhances the surface functionality. Therefore, it can serve as a versatile platform for various secondary reactions for a wide range of applications. Herein, the chemistry of DA is summarized and its polymerized form PDA for the modification of different families of materials’ surfaces with an emphasis on energy, environmental and biological applications.

The disposal of textile waste has become a growing issue worldwide. The rising consumption of clothing and textile materials has resulted in high waste generation. This could adversely impact environmental health, including humans, animals and plants. The three textile recycling methods can be divided into mechanical, chemical, and biological processes. There has been a focus on mechanical and chemical processes, pyrolysis, enzymatic hydrolysis, biological recycling, and microbial engineering in the area of textile waste managment. This review highlight the important parameters that affect the textile recycling performance and are significant for the success of the transformation process. To reach the zero-waste goal, textile recycling and converting this waste into value-added bioproducts are the necessary steps. The present review addresses the current status of textile recycling strategies, and the valorisation processes for converting textile waste materials into value-added products like biofuels, bioplastics, and others sustainable materials.

Ultra-high molecular weight polyethylene (UHMWPE) fiber is a new kind of high-performance fiber. Due to its excellent physical and chemical characteristics, it is widely used in various fields. However, the surface UHMWPE fiber is smooth and demonstrates no-polar groups. The weak interfacial adhesion between fiber and resin seriously restricts the applications of UHMWPE fiber. Therefore, the surface modification treatments of UHMWPE fiber are used to improve the interfacial adhesion strength. The modified method by adding nanomaterials elucidates the easy fabrication, advanced equipment and proper technology. Thus, the progress of UHMWPE nanocomposite fibers prepared via adding various nanofillers are reviewed. Meanwhile, the effects of other various methods on surface modification are also reviewed. This work advances the various design strategies about nano technologies on improving interfacial adhesion performance via treatment methodologies.

MXenes are emerging transition metal carbides and nitrides-based 2D conductive materials. They have found wide applications in sensors due to their excellent valuable properties. This paper reviews the recent research status of MXene-based electrochemical (bio) sensors for detecting biomarkers, pesticides, and other aspects. The first part of this paper introduced the synthesis strategy and the effect of surface modification on various properties of MXenes. The second part of this paper discussed the application of MXenes as electrode modifiers for detecting pesticides, environmental pollutants, and biomarkers such as glucose, hydrogen peroxide, etc. Hope this review will inspire more efforts toward research on MXene-based sensors to meet the growing requirements.

Nanotechnology has revolutionized cancer drug delivery, and recent research continues to focus on the development of “one-size- fits-all,” i.e., “all-in-one” delivery nanovehicles. Although nanomedicines can address significant shortcomings of conventional therapy, biological barriers remain a challenge in their delivery and accumulation at diseased sites. To achieve long circulation time, immune evasion, and targeted accumulation, conventional nanocarriers need modifications, e.g., PEGylation, peptide/aptamer attachment, etc. One such modification is a biomimetic coating using cell membrane (CM), which can offer long circulation or targeting, or both. This top-down CM coating process is facile and can provide some advantageous features over surface modification by synthetic polymers. Herein, an overview is provided on the engineering of CM camouflaged polymer nanoparticles. A short section on CM and the development of CM coating technology has been provided. Detailed description of the preparation and characterization of CM camouflaged polymer NPs and their applications in cancer treatment has been reported. A brief comparison between CM coating and PEGylation has been highlighted. Various targeting approaches to achieve tumor-specific delivery of CM coated NPs have been summarized here. Overall, this review will give the readers a nice picture of CM coated polymer NPs, along with their opportunities and challenges.

The burgeoning energy demand necessitates the demand for alternative sources of energy worldwide. The development and enhancement of energy storage devices are the main focus of researchers for sustainable energy production. Carbon supercapacitors have the potential applicability as a commercial source of power. Carbon‐based materials have been synthesized by utilization of ionic liquids (ILs). ILs exhibit unique properties, making them valuable materials to be utilized as a precursor, template, reaction media, and electrolytes for forming carbon‐based materials and enhancing supercapacitors (SCs) performance. This review article provides detailed information about ILs in the field of SCs. First, different attractive properties are illustrated, and then the role of ILs in producing carbon‐based materials in the SCs field is described. The next part provides detailed information regarding the utilization of ILs as electrolytes in carbon‐based SCs. Further, the implementations of ILs as electrolytes in different carbon‐based materials (such as activated carbon, graphene carbon nanotubes, and carbon nanofibers) in SCs are listed. Lastly, the importance of IL‐based materials from other materials and future prospects are provided to the readers, which helps further improve the sustainable development of SCs.

After the first visible photoluminescence (PL) from porous silicon (pSi), continuous efforts are made to fabricate Si‐based compound nanomaterials embedded in matrices such as oxide, nitride, and carbide to improve optical performance and industrial acceptability. These nanomaterials’ functional and desired properties (nanoparticles and quantum dots embedded in matrices) can vary significantly when embedded in technologically relevant matrices. However, exploring the exact emission mechanisms is one of the remaining challenges from the past few decades. To cover this gap, this review discusses the morphological and optoelectronic properties of Si‐based compound nanomaterials and their correlation with the quantum confinement effect and different surface states to find precise emission mechanisms. One of the biggest challenges of using silicon nanomaterials in the biological sector is the development of sensitive materials of low/acceptable toxicity for identifying target analytes either inside/outside the biological platforms. In this scenario, silicon‐based compound matrices can offer different characteristics and advantages depending on their size configurations and PL emission mechanisms. On the other hand, a proper understanding of these multifaceted silicon nanomaterials’ optical properties (emission mechanisms) can be exploited for pathogen detection and in situ applications in cells and tissues, embarking on a new era of bioimaging technology.

Abstract A novel castor oil‐based multifunctional polyol (CM) is fabricated through mild thiol‐ene photo induced reactions using castor oil (CO) and 1‐thioglycerol (MPD) as building blocks. The effect of the reaction time, molar ratio of thiol to carbon–carbon double bond, and the loadings of photo‐initiator are optimized. The resulting CM is combined with CO and employed as cross‐linkers to prepare castor oil‐based water‐borne polyurethane emulsion with desirable mechanical properties and water resistance. Owing to the incorporation of CM cross‐linker with high hydroxyl value of 371 mg KOH/g (which is 2.27 times higher than that of the CO), the prepared castor oil‐based waterborne polyurethane (CMWPU) possesses compacted 3D network structure with high cross‐linking degree, leading to improved glass transition temperature (45 °C), tensile strength (10.8 MPa), water contact angle (87.4°), and decreased water absorption rate (16.12%) with 20% CM additions. Overall, this work illustrates the feasibility of introducing bio renewable CM combined with CO to develop castor oil‐based WPU employing a sustainable development strategy.

Abstract Polybenzoxazines are high‐performance materials capable of replacing conventional thermosets such as phenolics, epoxies, and bismaleimides in composites manufacturing due to their excellent thermomechanical and chemical behavior. Their versatility and compatibility with biobased precursors make them an attractive option as composite matrices. Like other thermosets, polybenzoxazines are not recyclable and cannot be reprocessed. Incorporating dynamic bonds in benzoxazine monomers can produce vitrimeric polybenzoxazines, which can potentially overcome this limitation and can be tuned to exhibit smart functionalities such as self‐healing and shape memory. Dynamic bond exchange mechanisms for vitrimer development such as transesterification, imine bond, disulfide exchange, transamination, transcarbamoylation, transalkylation, olefin metathesis, transcarbonation, siloxane‐silanol exchange, boronic ester, silyl ether exchange, and dioxaborolane metathesis are potentially applicable to benzoxazine chemistry, with disulfide bond and transesterification having successfully vitrimerized benzoxazines with topological transitions at −8.5 and 88 °C, respectively. Benzoxazine vitrimers featuring glass transitions of 193, 224, and 222–236 °C are now known. These place polybenzoxazines at the forefront of the development of reprocessable and recyclable thermosetting polymers and composite matrices.

In the present era, different allotropes of carbon have been discovered, and graphene is the one among them that has contributed to many breakthroughs in research. It has been considered a promising candidate in the research and academic fields, as well as in industries, over the last decade. It has many properties to be explored, such as an enhanced specific surface area and beneficial thermal and electrical conductivities. Graphene is arranged as a 2D structure by organizing sp2 hybridized C with alternative single and double bonds, providing an extended conjugation combining hexagonal ring structures to form a honeycomb structure. The precious structure and outstanding characteristics are the major reason that modern industry relies heavily on graphene, and it is predominantly applied in electronic devices. Nowadays, lithium-ion batteries (LIBs) foremostly utilize graphene as an anode or a cathode, and are combined with polymers to use them as polymer electrolytes. After three decades of commercialization of the lithium-ion battery, it still leads in consumer electronic society due to its higher energy density, wider operating voltages, low self-discharge, noble high-temperature performance, and fewer maintenance requirements. In this review, we aim to give a brief review of the domination of graphene and its applications in LIBs.

Abstract Green chemistry has been a growing multidisciplinary field in recent years showing great promise in biomedical applications, especially for cancer therapy. Chitosan (CS) is an abundant biopolymer derived from chitin and is present in insects and fungi. This polysaccharide has favorable characteristics, including biocompatibility, biodegradability, and ease of modification by enzymes and chemicals. CS‐based nanoparticles (CS‐NPs) have shown potential in the treatment of cancer and other diseases, affording targeted delivery and overcoming drug resistance. The current review emphasizes on the application of CS‐NPs for the delivery of a chemotherapeutic agent, doxorubicin (DOX), in cancer therapy as they promote internalization of DOX in cancer cells and prevent the activity of P‐glycoprotein (P‐gp) to reverse drug resistance. These nanoarchitectures can provide co‐delivery of DOX with antitumor agents such as curcumin and cisplatin to induce synergistic cancer therapy. Furthermore, co‐loading of DOX with siRNA, shRNA, and miRNA can suppress tumor progression and provide chemosensitivity. Various nanostructures, including lipid‐, carbon‐, polymeric‐ and metal‐based nanoparticles, are modifiable with CS for DOX delivery, while functionalization of CS‐NPs with ligands such as hyaluronic acid promotes selectivity toward tumor cells and prevents DOX resistance. The CS‐NPs demonstrate high encapsulation efficiency and due to protonation of amine groups of CS, pH‐sensitive release of DOX can occur. Furthermore, redox‐ and light‐responsive CS‐NPs have been prepared for DOX delivery in cancer treatment. Leveraging these characteristics and in view of the biocompatibility of CS‐NPs, we expect to soon see significant progress towards clinical translation.

MXene‐based nanomaterial is a revolution 2D material achieving outstanding scientific attention owing to its universal characteristics for different applications (such as electronic appliances, power production, sensors, drug transfer, and biomedical). Although, the cytotoxic consequences of MXene have a considerable circumstance. Thus, rigorous investigation of the biocompatibility of MXene is a crucial prerequisite, formerly the preface to the human biological approach. Literature reveals functional outcomes wherever MXenes are used in vitro and in vivo cancer representatives. It affects drug transfer methods, sensoring electrodes, and assisting mechanisms for photothermal treatment and hyperthermy techniques. In this review, the synthesis process (such as top‐down and bottom‐up approaches) and properties (such as mechanical, electrical, optical, oxidative/thermal stability, and magnetic) of MXene‐based nanomaterials (NMs) are discussed. In addition, the different applications (such as tissue engineering, cancer theranostic, and other biomedical [such as drug delivery biosensors and surface‐enhanced Raman spectroscopy substrates for biomedical applications], antiviral, and immunomodulatory properties against SARS‐CoV‐2) of MXene‐based NMs are discussed in detail. Finally, the conclusion, existing challenges, and future outlooks are highlighted for more scope in this field.

Abstract Current interest toward ionic liquids (ILs) stems from some of their novel characteristics, like low vapor pressure, thermal stability, and nonflammability, integrated through high ionic conductivity and broad range of electrochemical strength. Nowadays, ionic liquids represent a new category of chemical‐based compounds for developing superior and multifunctional substances with potential in several fields. ILs can be used in solvents such as salt electrolyte and additional materials. By adding functional physiochemical characteristics, a variety of IL‐based electrolytes can also be used for energy storage purposes. It is hoped that the present review will supply guidance for future research focused on IL‐based polymer nanocomposites electrolytes for sensors, high performance, biomedicine, and environmental applications. Additionally, a comprehensive overview about the polymer‐based composites’ ILs components, including a classification of the types of polymer matrix available is provided in this review. More focus is placed upon ILs‐based polymeric nanocomposites used in multiple applications such as electrochemical biosensors, energy‐related materials, biomedicine, actuators, environmental, and the aviation and aerospace industries. At last, existing challenges and prospects in this field are discussed and concluding remarks are provided.

Carbon dots (CDs), an emerging category of carbon nanomaterials, have bright destiny in a vast diversity of engineering areas due to their great variety in design, arrangement, and characteristics. Their possible implementations have recently traversed from electrochemical energy storage (EES), fluorescent probing, and catalysis, particularly as materials into the critical elements of the electrochemical system. Herein, the current investigation based upon the preface of CDs in batteries, supercapacitors, hydrogen/oxygen evolution reaction, oxygen reduction reaction, electromagnetic interference shielding, and solar‐assisted energy generation used as electrode materials integrated with an active substance as an auxiliary mechanism is shown. Different aspects conferred upon selected illustrations outline the electrochemical activity, and eventually, current issues and future viewpoints are recollected toward the following optimization method of electrode substances. This review article is anticipated to demand broad attention within active CD materials and encourage the growth of high‐performance EES systems.

Despite metal oxides offer excellent characteristics in the field of photocatalysis, they often suffer from charge carrier recombination as well as limited visible response, which indeed reduce the charge kinetics process and ultimately reduce the photocatalytic output. Defect engineering is a sophisticated technique to manufacture defects and alter the geometric structure and chemical environment of the host. The present study provides an all-inclusive outline of recent developments on the classification of metal oxide defects based on the dimensions of a host crystal lattice. Precisely, surface modification of metal oxides through 0D (point), 1D (line), 2D (planar), and 3D (volume) defects with their subsequent mechanism and impact on photocatalytic performance are presented. By wisely amending the morphology (cores along with the shells) and electronic structure of metal oxide photocatalysts (TiO2, ZnO, Bi2O3, Fe2O4 etc.) through different attuned and veritable approaches, their photocatalytic activity can be substantially improved. Optimal studies on defect engineering not only expose the altered physicochemical features but also modulate the electron-hole pair dynamics, stability, and active radical production for various photoredox reactions. Altered atomic, as well as electronic configuration, facilitated a photocatalyst material to have different optical features, adsorption properties along with improved carrier transfer as well as isolation rate. Thus, the systematic exploration of photocatalytic rudiments of defect rich metal oxide for various applications such as H2 evolution, CO2 reduction, pollutant degradation, and bacterial disinfection could bring significant research advancement in this field.

Abstract Rhamnolipids (RLs) are surface-active compounds and belong to the class of glycolipid biosurfactants, mainly produced from Pseudomonas aeruginosa. Due to their non-toxicity, high biodegradability, low surface tension and minimum inhibitory concentration values, they have gained attention in various sectors like food, healthcare, pharmaceutical and petrochemicals. The ecofriendly biological properties of rhamnolipids make them potent materials to be used in therapeutic applications. RLs are also known to induce apoptosis and thus, able to inhibit proliferation of cancer cells. RLs can also act as immunomodulators to regulate the humoral and cellular immune systems. Regarding their antimicrobial property, they lower the surface hydrophobicity, destruct the cytoplasmic membrane and lower the critical micelle concentration to kill the bacterial cells either alone or in combination with nisin possibly due to their role in modulating outer membrane protein. RLs are also involved in the synthesis of nanoparticles for in vivo drug delivery. In relation to economic benefits, the post-harvest decay of food can be decreased by RLs because they prevent the mycelium growth, spore germination of fungi and inhibit the emergence of biofilm formation on food. The present review focuses on the potential uses of RLs in cosmetic, pharmaceutical, food and health-care industries as the potent therapeutic agents.

In this work, we report for the first time the clean manufacturing of cellulose nanopapers by a green path of mixing nanocellulose suspension in water with lignin and xylan. The procedure involves grinding the old wastepaper, microfluidizing, casting, and water evaporation. The introduction of lignin and xylan with various loadings from 1 to 30 wt% showed that properties could be significantly tuned. Moreover, lignin and xylan loadings introduced into these nanopapers endow them with improved mechanical and structural properties, as evidenced by tensile tests and scanning electron microscopy analysis (SEM). Xylan strongly promotes the transparency of nanopapers. Even at low loadings, the addition of xylan and lignin enhanced specific strength by 1.3-fold, while specific elastic modulus was found to exhibit a a 2-fold enhancement. Mathematical modeling complemented the analysis of tensile properties. Thermogravimetric analysis testified that the wastepaper is made of highly purified cellulose. Furthermore, thermal properties analysis shows that the modified nanopapers have higher thermal conductivity and diffusivity than the unmodified ones. Thermal conductivity was found to improve 3.5-fold for compositions with 30 wt% loading of modifiers corresponding to the developed denser structure as revealed by SEM. The introduced crosscut and surface structure changes enable functional applications to obtain packaging, filtering, biomedical, and sensor materials.

Abstract Over 80% of wastewater worldwide is released into the environment without proper treatment. Whilst environmental pollution continues to intensify due to the increase in the number of polluting industries, conventional techniques employed to clean the environment are poorly effective and are expensive. MXenes are a new class of 2D materials that have received a lot of attention for an extensive range of applications due to their tuneable interlayer spacing and tailorable surface chemistry. Several MXene‐based nanomaterials with remarkable properties have been proposed, synthesized, and used in environmental remediation applications. In this work, a comprehensive review of the state‐of‐the‐art research progress on the promising potential of surface functionalized MXenes as photocatalysts, adsorbents, and membranes for wastewater treatment is presented. The sources, composition, and effects of wastewater on human health and the environment are displayed. Furthermore, the synthesis, surface functionalization, and characterization techniques of merit used in the study of MXenes are discussed, detailing the effects of a range of factors (e.g., PH, temperature, precursor, etc.) on the synthesis, surface functionalization, and performance of the resulting MXenes. Finally, the limits of MXenes and MXene‐based materials as well as their potential future research directions, especially for wastewater treatment applications are highlighted.

Abstract Background Integrated management of hemicellulosic fraction and its economical transformation to value-added products is the key driver towards sustainable lignocellulosic biorefineries. In this aspect, microbial cell factories are harnessed for the sustainable production of commercially viable biochemicals by valorising C5 and C6 sugars generated from agro-industrial waste. However, in the terrestrial ecosystem, microbial systems can efficiently consume glucose. On the contrary, pentose sugars are less preferred carbon source as most of the microbes lack metabolic pathway for their utilization. The effective utilization of both pentose and hexose sugars is key for economical biorefinery. Results Bioprospecting the food waste and selective enrichment on xylose-rich medium led to screening and isolation of yeast which was phylogenetically identified as Pichia fermentans. The newly isolated xylose assimilating yeast was explored for xylitol production. The wild type strain robustly grew on xylose and produced xylitol with > 40% conversion yield. Chemical mutagenesis of isolated yeast with ethyl methanesulphonate (EMS) yielded seven mutants. The mutant obtained after 15 min EMS exposure, exhibited best xylose bioconversion efficiency. This mutant under shake flask conditions produced maximum xylitol titer and yield of 34.0 g/L and 0.68 g/g, respectively. However, under the same conditions, the control wild type strain accumulated 27.0 g/L xylitol with a conversion yield of 0.45 g/g. Improved performance of the mutant was attributed to 34.6% activity enhancement in xylose reductase with simultaneous reduction of xylitol dehydrogenase activity by 22.9%. Later, the culture medium was optimized using statistical design and validated at shake flask and bioreactor level. Bioreactor studies affirmed the competence of the mutant for xylitol accumulation. The xylitol titer and yield obtained with pure xylose were 98.9 g/L and 0.67 g/g, respectively. In comparison, xylitol produced using non-detoxified xylose rich pre-hydrolysate from sugarcane bagasse was 79.0 g/L with an overall yield of 0.54 g/g. Conclusion This study demonstrates the potential of newly isolated P. fermentans in successfully valorising the hemicellulosic fraction for the sustainable xylitol production.

Abstract Background Xylose is the most prevalent sugar available in hemicellulose fraction of lignocellulosic biomass (LCB) and of great interest for the green economy. Unfortunately, most of the cell factories cannot inherently metabolize xylose as sole carbon source. Yarrowia lipolytica is a non-conventional yeast that produces industrially important metabolites. The yeast is able to metabolize a large variety of substrates including both hydrophilic and hydrophobic carbon sources. However, Y. lipolytica lacks effective metabolic pathway for xylose uptake and only scarce information is available on utilization of xylose. For the economica feasibility of LCB-based biorefineries, effective utilization of both pentose and hexose sugars is obligatory. Results In the present study, succinic acid (SA) production from xylose by Y. lipolytica was examined. To this end, Y. lipolytica PSA02004 strain was engineered by overexpressing pentose pathway cassette comprising xylose reductase (XR), xylitol dehydrogenase (XDH) and xylulose kinase (XK) gene. The recombinant strain exhibited a robust growth on xylose as sole carbon source and produced substantial amount of SA. The inhibition of cell growth and SA formation was observed above 60 g/L xylose concentration. The batch cultivation of the recombinant strain in a bioreactor resulted in a maximum biomass concentration of 7.3 g/L and SA titer of 11.2 g/L with the yield of 0.19 g/g. Similar results in terms of cell growth and SA production were obtained with xylose-rich hydrolysate derived from sugarcane bagasse. The fed-batch fermentation yielded biomass concentration of 11.8 g/L (OD600: 56.1) and SA titer of 22.3 g/L with a gradual decrease in pH below 4.0. Acetic acid was obtained as a main by-product in all the fermentations. Conclusion The recombinant strain displayed potential for bioconversion of xylose to SA. Further, this study provided a new insight on conversion of lignocellulosic biomass into value-added products. To the best of our knowledge, this is the first study on SA production by Y. lipolytica using xylose as a sole carbon source.

Advances in noble metal mediated Z-scheme photocatalytic system have ushered in a climax on environmental remediation. Herein, graphitic carbon nitride (GCN) and phosphorus sulphur co-doped graphitic carbon nitride (PSCN) were synthesized via calcination process. GCN, PSCN and Z-scheme visible light driven (VLD) ternary BiOBr/PSCN/Ag/AgCl nanophotocatalyst were characterized by X-ray diffraction pattern (XRD), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV–visible diffuse reflectance spectra (UV–vis DRS). BiOBr/PSCN/Ag/AgCl nanocomposite exhibited superior visible light driven photocatalytic ability as compared to pristine PSCN, AgCl and BiOBr towards degradation of phenol. The results explicated promising photocatalytic activity along with space separation of photocarriers caused via formation of BiOBr/PSCN/Ag/AgCl Z-scheme heterojunction. The visible light absorption efficacy of BiOBr/PSCN/Ag/AgCl photocatalyst was confirmed by photoluminescence (PL) spectra. Finally, recycling experiments were explored for the mechanistic detailing of phenol photodegradation employing BiOBr/PSCN/Ag/AgCl photocatalyst. After seven successive cycles photodegradation efficacy of photocatalyst was reduced to 90% from 98%. Proposed mechanism of BiOBr/PSCN/Ag/AgCl nanophotocatalyst for degradation of phenol was discussed. OH· and O2·− radicals were main reactive species responsible for photocatalytic phenol degradation. Keywords: BiOBr, Ag/AgCl, P and S co-doped g-C3N4, Dual Z-scheme approach, Enhanced photocatalysis, Phenol degradation

Advanced oxidation processes (AOPs) counting heterogeneous photocatalysis has confirmed as one of the preeminent method for waste water remediation. In the present work, we have successfully fabricated novel visible-light-driven nitrogen-doped graphene (NG) supported magnetic ZnO/ZnFe2O4 (ZnO/ZF/NG) and ZnO/CoFe2O4 (ZnO/CF/NG) nanocomposites. ZnO synthesized via direct precipitation method. Hydrothermal method was used for the preparation of nitrogen-doped graphene supported magnetic ZnO/ZF (ZnO/ZnFe2O4) and ZnO/CF (ZnO/CoFe2O4) nanocomposites. The procured materials were scrutinized by assorted characterizations to acquire information on their chemical composition, crystalline structure and photosensitive properties. The absorption and photocatalytic performance of photocatalysts were studied via UV–Visible spectra. Photodegradation performance of the synthesized nanocomposites was estimated toward mineralization of methyl orange (MO) and malachite green (MG) dyes in aqueous solution. The high surface area of ZnO/ZF/NG and ZnO/CF/NG was suitable for adsorptive removal of MO and MG dyes. The photodegradation performance of heterojunction photocatalysts was superior to bare photocatalyst in 140 min under visible-light irradiation. Spectrophotometer, GC–MS (Gas chromatography–mass spectrometry) elucidation was carried out to expose the possible intermediates formed. Both ZnO/ZF/NG and ZnO/CF/NG were rapidly isolated from the aqueous phase by applying an external magnetic field in 20 sec and 2 min, respectively. The photocatalytic performance and stability of ZnO/ZF/NG and ZnO/CF/NG nanocomposites were confirmed by conducting 10 consecutive regeneration cycles. Owing to recyclability of ZnO/ZF/NG and ZnO/CF/NG, these heterogeneous nanocomposites might be used as cost-effective for treatment of discarded water. The observations endorse that the synthesized ternary heterogeneous nanocomposites facilitates wastewater decontamination using photocatalytic technology. Keywords: ZnFe2O4, CoFe2O4, Nitrogen doped graphene, Supported photocatalysis Magnetic separation, Dye mineralization, Recycle efficiency

The unique attributes, biodegradability, biocompatibility, perfect accessibility, and low production costs led to the use of natural gums in a different section of our lives. Among them, we can mention gums obtained from microorganisms (xanthan gum and gellan gum), plant tissues (Arabic gum and gum tragacanth), seeds (konjac gum and guar gum), seaweeds (alginates, agar gum, and carrageenans). Gums have essential applications in the medical and pharmaceutical, food, biotechnology, and critical agricultural industries. Encapsulation is one of the new methods to increase the stability of bioactive compounds during processing and storage. Encapsulation technology using natural gums is a new way to improve the performance of microbial agents in various sciences, especially agriculture, which represents a bright future in this field.

Viruses are widely recognized as the primary cause of infectious diseases around the world. The ongoing global pandemic due to the emergence of SARS-CoV-2 further added fuel to the fire. The development of therapeutics becomes very difficult as viruses can mutate their genome to become more complex and resistant. Medicinal plants and phytocompounds could be alternative options. Isoquinoline and their related alkaloids are naturally occurring compounds that interfere with multiple pathways including nuclear factor-κB, mitogen-activated protein kinase/extracellular-signal-regulated kinase, and inhibition of Ca2+-mediated fusion. These pathways play a crucial role in viral replication. Thus, the major goal of this study is to comprehend the function of various isoquinoline and related alkaloids in viral infections by examining their potential mechanisms of action, structure-activity relationships (SAR), in silico (particularly for SARS-CoV-2), in vitro and in vivo studies. The current advancements in isoquinoline and related alkaloids as discussed in the present review could facilitate an in-depth understanding of their role in the drug discovery process.

Abstract Piezoelectric materials are widely referred to as “smart” materials because they can transduce mechanical pressure acting on them to electrical signals and vice versa. They are extensively utilized in harvesting mechanical energy from vibrations, human motion, mechanical loads, etc., and converting them into electrical energy for low power devices. Piezoelectric transduction offers high scalability, simple device designs, and high‐power densities compared to electro‐magnetic/static and triboelectric transducers. This review aims to give a holistic overview of recent developments in piezoelectric nanostructured materials, polymers, polymer nanocomposites, and piezoelectric films for implementation in energy harvesting. The progress in fabrication techniques, morphology, piezoelectric properties, energy harvesting performance, and underpinning fundamental mechanisms for each class of materials, including polymer nanocomposites using conducting, non‐conducting, and hybrid fillers are discussed. The emergent application horizon of piezoelectric energy harvesters particularly for wireless devices and self‐powered sensors is highlighted, and the current challenges and future prospects are critically discussed.

The rapid e-waste volume is generating globally. At the same time, different recycling technologies, mainly the mechanical and chemical methods well studied, while the biological method is the most promising approach. Therefore, this article provides a comprehensive information about extracting valuable metals from e-waste. In addition, this article outlines the process and key opportunity for extraction of metals, identifies some of the most critical challenges for e-waste environmentally sound management practices, and opinions on possible solutions for exiting challenges, and emphasis on importance of advanced recycling technologies that can be utilized, in order to minimize the environmental impact causes due to improper recycling of e-waste.

The Zinc-doped cerium oxide nanocomposite (ZnO/CeO2 NC) was synthesized using a metal-organic framework as a precursor through the combustion method. It was characterized by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), field emission electron microscopy (FESEM), energy dispersive analysis (EDX), transmission electron microscopy (TEM), dynamic light scattering (DLS), and ξ-potential. The PXRD demonstrated the successful synthesis of ZnO/CeO2 NC with a crystallite size of 31.9 nm. FESEM and TEM images displayed hexagonal and spherical morphologies, and the solid-phase size was 65.03 ± 30.86 nm for ZnO/CeO2 NCs. DLS, TEM, and FESEM showed that the NCs have a high tendency for agglomeration/aggregation in both aqueous media and solid phase. The anticancer attributes of ZnO/CeO2 NC were investigated against Liver cancer cells (HepG2), which showed inhibition of cancer cell growth on a concentration-dependent gradient. The cell toxicity effects of ZnO/CeO2 nanocomposites were also studied toward NIH-3T3, in which the data displayed the lower toxicity of NC compared to the HepG2 cell line.

In the present study, nickel ferrite (NiFe2O4)-based smart magnetic nanoparticles were fabricated and coated with methionine. Physiochemical characterization of the obtained Met-NiFe2O4 nanoparticles revealed the presence of methionine coating over the nanoparticle surface. Drug release study indicated that Tet-Met-NiFe2O4 nanoparticles possess pH-responsive controlled drug release behavior for tetracycline (Tet). The drug loading content for Tet was found to be 0.27 mg/L of nanoparticles. In vitro cytotoxicity test showed that the Met-NiFe2O4 nanoparticles is biocompatible. Moreover, this magnetic nanostructured material shown strong anticancer property as these nanomaterials significantly reduced the viability of A375 cells when compared to free Tet solution. In addition, Tet-Met-NiFe2O4 nanoparticles also showed strong antibacterial activity against different bacterial pathogens.

Fluoroquinolones are of pivotal interest for scientists because of their excellent pharmacological and pharmacokinetic profiles. They have a broad spectrum of antimicrobial activity and show several promising features such as, greater bioavailability, admirable tissue penetration and comparatively lower incidence of antagonistic and lethal effects. These have made the compounds highly desirable to combat several infectious diseases. Various synthetic conventions have been established to hasten the fluoroquinolone’s amination rate and to improve yield. Such methods have significant disadvantages including, costly reagents, usage of vast quantities of harmful solvents, excessive heat and sideways reactions. These drawbacks aren’t appropriate in current pharmaceutical market. Hence, it is highly desirable to develop a newer green and more efficient process for fluoroquinolones synthesis. Green chemistry methodology endeavours to achieve sustainability at the molecular level. The field of green chemistry has shown how chemists can design next-generation products and processes to make them more cost-effective while being virtuous for human health and the environment. This graphical review demonstrates the current developments in the synthesis of fluoroquinolones employing the principles of green chemistry by using the novel, recyclable and environmental-friendly catalysts and solvents.

There has been a growing concern for safety and precautions in the wake of coronavirus SARS-CoV2 pandemic also dubbed as COVID-19, which has caused a major impact at a global scale. This has resulted in many industries accelerating at fast pace new biosafety technologies and improving the already existing ones to deal with this highly contagious virus. Most governments across the globe are also mandating policies focusing on increased biosafety to prevent further spread of the virus and protect key workers such as healthcare agents, store employees and police. The COVID-19 pandemic has exposed huge gaps in the healthcare industry that include lack of effective vaccines and medicines, testing of infection, real-time monitoring of the spread of the virus, inadequate protective equipment, and scarcity of protective and intensive care of patients. Some of these may be attributed to a lack of focused research in biosafety materials. As a consequence of the pandemic, a significant body of research activities has therefore focused on biosafety materials that possess unique properties needed for biosafety applications. This graphical review aims to provide a perspective on the usage of bio-based materials to handle the imposing challenges in biosafety. This review investigates existing developments in bio-based antimicrobial encapsulations as an effective measure to deter the growth of COVID-19 virus on surfaces and minimize its spread through surface contact. This will help researchers develop further strategies in material science to focus on contagious pathogens in the future.

After the eruption of the most deadly influenza flu pandemic in 1918, also known as Spanish flu, infected about 500 million people with a death toll of approximately 50 million globally, the second most devastating pandemic flu emerged in December 2019 ​at Wuhan (Hubei Province) of China. This viral disease caused by a novel coronavirus SARS-COV-2 was named COVID-19 by World Health Organization (WHO). The COVID-19 virus affected 213 countries globally with 5.6 million cases and 353,373 deaths as of May 28, 2020 [1] Fig. 1. Still, there is no promising solution known to tackle this severe epidemic disease worldwide. For protecting the global population from COVID-19, we must follow three steps – early detection, monitoring, and treatment. At the same time, it is important to follow WHO guidelines on preventive measures. Many countries have restricted the movement of people completely and lockdown was enforced to maintain social distancing. But lockdown alone is insufficient to prevent resurgence, can upend economies and roil society. People need to step out to perform essential tasks and may get exposed to this deadly virus. Learnings from previous outbreaks suggest the usage of nanotechnology as an important avenue to develop antiviral drugs and materials. So, to effectively minimize the acquired infection of COVID-19 in public places like hospitals, transport, schools, worship places, stores, malls, etc. Antimicrobial nanocoatings at these places and development of targeted antiviral drugs through capped nanoparticles will be a major effective option to tackle the spread of this disease.

Thiazolidin-4-one has been known as a powerful moiety present in various approved medications. Thiazolidin-4-ones are amongst the most effective and actively explored fields of current antimicrobial and antiviral chemotherapy that portray broad spectrum and potent activity. The wide range of medicinal properties of thiazolidin-4-one related drugs encourages the medicinal chemists to synthesize a significant variety of new medicinal substances. Microwave induced organic reactions earned substantial coverages in recent years due to many advantages such as ease of work, cost-effectiveness, short reaction time and excellent yield. Microwave radiations provide a substitute for traditional heating by incorporating energy to the reactions. The usage of microwave irradiation has contributed to the emergence of innovative ideas in chemistry, as energy absorption and propagation in microwave irradiation is entirely dissimilar to the traditional heating method. In synthetic chemistry, microwave heating is a rapidly growing area of research. This review cover organic synthesis of thiazolidin-4-one analogues via the use of microwave irradiation as an effective technique and the antiviral and antimicrobial action of thiazolidin-4-one based compounds.

Bio-based aerogels with customizable porosities and functionalities constitute a significant potential for CO2 capture. Developing bio-based aerogels from different polysaccharides and proteins is a safe, economical, and environmentally sustainable approach. Polysaccharides are biodegradable, sustainable, renewable, and plentiful in nature. Because of these advantages, the use of bio-based aerogels with porosity and amine functionality has attracted considerable interest. In this review, we have discussed the recent development in the synthesis of bio-based aerogels and their application in CO2 capture.

The aim of the present study is to examine the effect of the addition of carbon nanoparticles (σsp2 hybridization) on the mechanical properties of foamed polystyrene. In this work, we focus on the study of the impact of compressive stress, tensile strength, bending strength, thermal conductivity ratio (λ), and water absorption of expanded polystyrene (EPS) reinforced with reduced graphene oxide and graphite. The results were compared with pristine EPS and reduced graphene oxide-reinforced EPS. All the nanocomposite specimens used for testing had a similar density. The study reveals that the nanocomposites exhibit different thermal conductivities and mechanical properties in comparison to pristine EPS. The enhancement in the properties of the nanocomposite could be associated with a more extensive structure of elementary cells of expanded polystyrene granules.

Bone marrow-derived mesenchymal stem cells (MSCs) offer a promising therapeutic method for cardiac tissue regeneration. However, to monitor the fate of MSCs for tissue repair, a better stem cell delivery carrier is needed. Developing a unique injectable and shear-thinning dual cross-linked hybrid hydrogel for MSC delivery for cardiac tissue engineering is highly desirable. This hydrogel was synthesised using guest: host reaction based on alginate-cyclodextrin (Alg-CD) and adamantane-graphene oxide (Ad-GO). Here, the role of macromere concentration (10 and 12%) on the MSC function is discussed. Our hybrid hydrogels reveal a suitable oxygen pathway required for cell survival. However, this value is strongly dependent on the macromere concentrations, while the hydrogels with 12% macromere concentration (2DC12) significantly enhanced the oxygen permeability value (1.16-fold). Moreover, after two weeks of culture, rat MSCs (rMSCs) encapsulated in Alg-GO hydrogels expressed troponin T (TNT) and GATA4 markers. Noticeably, the 2DC12 hydrogels enhance rMSCs differentiation markers (1.30-times for TNT and 1.21-times for GATA4). Overall, our findings indicate that tuning the hydrogel compositions regulates the fate of encapsulated rMSCs within hydrogels. These outcomes may promote the advancement of new multifunctional platforms that consider the spatial and transient guidelines of undifferentiated cell destiny and capacity even after transplantation for heart tissue regeneration.

Research progress on sustainable and renewable biofuel has gained motion over the years, not just due to the rapid reduction of dwindling fossil fuel supplies but also due to environmental and potential energy security issues as well. Intense interest in microalgae (photosynthetic microbes) as a promising feedstock for third-generation biofuels has grown over recent years. Fuels derived from algae are now considered sustainable biofuels that are promising, renewable, and clean. Therefore, selecting the robust species of microalgae with substantial features for quality biodiesel production is the first step in the way of biofuel production. A contemporary investigation is more focused on several strategies and techniques to achieve higher biomass and triglycerides in microalgae. The improvement in lipid enhancement in microalgae species by genetic manipulation approaches, such as metabolic or genetic alteration, and the use of nanotechnology are the most recent ways of improving the production of biomass and lipids. Hence, the current review collects up-to-date approaches for microalgae lipid increase and biodiesel generation. The strategies for high biomass and high lipid yield are discussed. Additionally, various pretreatment procedures that may aid in lipid harvesting efficiency and improve lipid recovery rate are described.