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.

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.

Application of cobalt-cerium-iron ternary layered double hydroxide for extraction of perfluorooctane sulfonate followed by HPLC-MS/MS analysis.

Herein, Ce-doped CoFe layered double hydroxide (LDH), noted as CoCeFe ternary LDH, was prepared using the co-precipitation route. Prosperous synthesis of CoFe LDH and successful partial replacement of iron cations with cerium cations in CoCeFe ternary LDH were confirmed by X-ray diffraction patterns, energy-dispersive X-ray spectroscopy, and elemental dot-mapping images. Nanosheet morphology was recognized for both CoFe LDH and CoCeFe ternary LDH from scanning electron microscopy and transmission electron microscopy micrographs. In the following, a dispersive solid phase extraction (DSPE) method was developed using the synthesized CoCeFe ternary LDH as a sorbent for extracting perfluorooctanesulfonic acid (PFOS) from wastewater samples. For the selective analysis of PFOS, high-performance liquid chromatography-tandem mass spectroscopy (HPLC-MS/MS) in multiple reaction monitoring mode was used. Analytical parameters such as the limit of detection equal to 0.02 µg/L, with a linear range of 0.05-300 µg/L, the limit of quantification equal to 0.05 µg/L, and an enrichment factor equal to 23.3 were achieved for PFOS at the optimized condition (sorbent: 5 mg of CoCeFe ternary LDH, eluent type and volume: 150 µL mobile phase, pH: 3, adsorption time: 3 min, and desorption time: 5 min). The developed strategy for the analysis of PFOS was tested in real wastewater samples, including copper mine and petrochemical wastewater. The amount of analytes in real samples was calculated using the standard addition method, and good relative recovery in the range of 86%-105% was obtained. The main novelty of this research is the application of CoCeFe ternary LDH to extract the PFOS from wastewater using the DSPE method for determination by HPLC-MS/MS.

An enzyme-free sensor based on La-doped CoFe-layered double hydroxide decorated on reduced graphene oxide for sensitive electrochemical detection of urea.

The successful synthesis of La-doped CoFe LDH@rGO nanocomposite is reported combining the advantages of LDH and rGO and shows promising performances in electrochemical sensors. The structure of the obtained nanocomposite was investigated using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction pattern (XRD), and field emission scanning electron microscope images (FE-SEM). Then, it was directly utilized to construct a carbon paste electrode (CPE) for urea detection. The electrochemical performance of the sensor was evaluated by various electrochemical methods. The La-CoFe LDH@rGO electrode exhibited excellent electrocatalytic properties, including a wide linear working range of 0.001-23.5 mM, very high sensitivity of 1.07 ± 0.023 µA µM-1 cm-2, a low detection limit of 0.33 ± 0.11 µM, and rapid response time of 5 s towards urea detection at the working potential of 0.4 V. Furthermore, the sensor displayed a high selectivity in different matrices, appropriate reproducibility, and long shelf life without activity loss during 3 months of storage under ambient conditions. Further tests were performed on serum and milk samples to confirm the capability of the proposed sensor for practical applications, demonstrating a reasonable recovery of 94.8 to 102% with an RSD value below 3%. Consequently, the synergistic effect of each component led to the good electrocatalytic activity of the modified electrode towards urea.

Insights into engineered graphitic carbon nitride quantum dots for hazardous contaminants degradation in wastewater.

Increased environmental pollution is a critical issue that must be addressed. Photocatalytic, adsorption, and membrane filtration methods are suitable in environmental governance because of their high selectivity, low cost, environment-friendly nature, and excellent treatment efficiency. Graphitic carbon nitride (g-C3N4) quantum dots (QDs) have been considered as photocatalysts, adsorbents, and membrane materials for wastewater treatments, owing to their stability, adsorption capacity, photochemical properties, and low toxicity and cost. This review summarizes g-C3N4 QD synthesis techniques, operating parameters affecting the removal performance in the treatment process, modification effects with other semiconductors, and benefits and drawbacks of g-C3N4 QD-based materials. Furthermore, this review discusses the practical applications of g-C3N4 QDs as adsorbents, photocatalysts, and membrane materials for organic and inorganic contaminant treatments and their value-added product formation potential. Modified g-C3N4 QD-based material adsorbents, photocatalysts, and membranes present potentially applicable effects, such as removal of most waterborne contaminants. Excellent results were obtained for the reduction of methyl orange, bisphenol A, tetracycline, ciprofloxacin, phenol, rhodamine B, E. coli, and Hg. Overall, this paper provides comprehensive background on g-C3N4 QD-based materials and their diverse applications in wastewater treatment, and it presents a foundation for the enhancement of similar unique materials in the future.

Bamboo-derived adsorbents for environmental remediation: A review of recent progress.

The bamboo family of plants is one of the fastest-growing species in the world. As such, there is an abundance of bamboo residues available for exploitation, especially in southeast Asian, central African and south American regions. The preparation of efficient adsorbents from bamboo residues is an emerging exploitation pathway. Biochars, activated carbons or raw bamboo fibers embedded with nanoparticles, each class of materials has been shown to be highly efficient in adsorption processes. This review aims to summarize recent findings in the application of bamboo-based adsorbents in the removal of organic, inorganic, or gaseous pollutants. Therefore, this review first discusses the preparation methods and surface modification methodologies and their effects on the adsorbent elemental content and other basic properties. The following sections assess the recent progress in the adsorption of heavy metals, organics, and gaseous substances by bamboo-based adsorbents, focusing on the optimum adsorption capacities, adsorption mechanisms and the optimum-fitting kinetic models and isotherms. Finally, research gaps were identified and directions for future research are proposed.

Self-assembled monolayer-assisted label-free electrochemical genosensor for specific point-of-care determination of Haemophilus influenzae.

For sensitive detection of the L-fuculokinase genome related to the Haemophilus influenzae (H. influenzae), this research work demonstrates the label-free electrochemical-based oligonucleotide genosensing assay relying on the performing hybridization process. To enhance the electrochemical responses, multiple electrochemical modifier-tagged agents were effectively utilized. For attaining this goal, NiCr-layered double hydroxide (NiCr LDH) has been synthesized and combined with biochar (BC) to create an efficient electrochemical signal amplifier that has been immobilized on the surface of the bare Au electrode. Low detection and quantification limits (LOD and LOQ) associated with the designed genosensing bio-platform to detect L-fuculokinase have been achieved to 6.14 fM and 11 fM, respectively. Moreover, the wide linear range of 0.1 to 1000 pM demonstrates the capability of the designed platform. Investigated were the 1-, 2-, and 3-base mismatched sequences, and the negative control samples clarified the high selectivity and better performance of the engineered assay. The values of 96.6-104% and 2.3-3.4% have been obtained for the recoveries and RSDs, respectively. Furthermore, the repeatability and reproducibility of the associated bio-assay have been studied. Consequently, the novel method is appropriate for rapidly and quantitatively detecting H. influenzae, and is considered a better candidate for advanced tests on biological samples such as urine samples.

Degradation of emerging pollutants on bifunctional ZnFeV LDH@graphite felt cathode through prominent catalytic activity in heterogeneous electrocatalytic processes.

The heterogeneous Electro-Fenton (EF) process is a promising wastewater treatment technology that can generate onsite H2O2, and operate in a wide pH range without generating a metal sludge. However, the heterogeneous EF process needs bifunctional cathode electrodes that can have high activity in 2e- oxygen reduction reaction and H2O2 decomposition. Herein, ZnFeV layered double hydroxide (LDH), as a heterogeneous catalyst, was coated on the graphite felt (ZnFeV LDH@GF) cathode using the electrophoretic deposition method. ZnFeV LDH@GF cathode was able to generate 59.8 ± 5.9 mg L-1 H2O2 in 90 min under a constant supply of O2. EF process with ZnFeV LDH@GF cathode exhibited 89.8 ± 6.8% removal efficiency for pharmaceutical (ciprofloxacin) at neutral pH. Remarkably, the apparent reaction rate constant (kapp) of the ZnFeV LDH@GF-EF was 2.14 times that of the EF process with pristine GF. ZnFeV LDH coating increased the hydroxyl radical (•OH) production of the EF process from 1.74 mM to 3.65 mM. The pathway of •OH production is thought to be a single electron transfer from redox couples of Fe2+/Fe3+ and [Formula: see text] to H2O2. After 10 reuse cycles, the ZnFeV LDH@GF cathode retained 90.2% of its efficiency. Eight intermediate compounds were identified by GC-MS including cyclic compounds and aliphatic compounds.

Modification of reinforced hollow fiber membranes with WO3 nanosheets for treatment of textile wastewater by membrane bioreactor.

In this study, performance of braid reinforced hollow fiber membrane containing polyvinylidene fluoride (PVDF) embedded with tungsten trioxide (WO3) nanosheets in a membrane bioreactor (MBR) was examined for textile wastewater treatment. The WO3 nanosheets was synthesized and blended at different concentrations (0.1-0.02 wt%) in casting solutions of the membranes. The WO3 nanosheets characterized using various tests such as XRD, FTIR, SEM, EDS, dot-mapping, and TEM. Furthermore, the effects of the increased WO3 nanosheets into the PVDF matrix on the membrane morphology, hydrophilicity, permeability, antifouling, and COD and color removal efficiency was investigated. The addition of 0.1 wt% of the nanosheets reduces the water contact angle from 69.3° to 62.5° while increasing overall porosity from 37.5 to 43.2%. COD and color removal for PVDF/0.10 wt% WO3 membrane was between 86-89% and 72-76%, respectively. While the TMP of modified WO3 membranes did not significantly increase due to antimicrobial properties of the WO3 nanosheets, the TMP of the pure PVDF membrane increase, indicating considerable cake layer fouling. The results of this study showed that modification of PVDF braid reinforced hollow fiber membrane using WO3 nanosheets is promising membrane for MBR systems.

Patulin and Trichothecene: characteristics, occurrence, toxic effects and detection capabilities via clinical, analytical and nanostructured electrochemical sensing/biosensing assays in foodstuffs.

Patulin and Trichothecene as the main groups of mycotoxins in significant quantities can cause health risks from allergic reactions to death on both humans and animals. Accordingly, rapid and highly sensitive determination of these toxics agents is of great importance. This review starts with a comprehensive outlook regarding the characteristics, occurrence and toxic effects of Patulin and Trichothecene. In the following, numerous clinical and analytical approaches have been extensively discussed. The main emphasis of this review is placed on the utilization of novel nanomaterial based electrochemical sensing/biosensing tools for highly sensitive determination of Patulin and Trichothecene. Furthermore, a detailed and comprehensive comparison has been performed between clinical, analytical and sensing methods. Subsequently, the nanomaterial based electrochemical sensing platforms have been approved as reliable tools for on-site analysis of Patulin and Trichothecene in food processing and manufacturing industries. Different nanomaterials in improving the performance of detecting assays were investigated and have various benefits toward clinical and analytical methods. This paper would address the limitations in the current developments as well as the future challenges involved in the successful construction of sensing approaches with the functionalized nanomaterials and also allow exploring into core-research works regarding this area.[Formula: see text].

Emerging electrochemical sensing and biosensing approaches for detection of Fumonisins in food samples.

Fumonisins (FBs) can be found extensively in feedstuffs, foodstuffs, and crops. The consumption of the fumonisin-contaminated corn can result in esophageal cancer. In addition, the secondary metabolites of fungi termed mycotoxins may have some adverse effects on animals and humans such as estrogenicity, immunotoxicity, teratogenicity, mutagenicity, and carcinogenicity. Hence, developing sensitivity techniques for mycotoxins determination is of great importance. This paper reports the latest developments of nanomaterial-based electrochemical biosensing, apta-sensing, sensing, and immunosensing analyses to detect fumonisins. A concise study of the occurrence, legislations, toxicity, and distribution of FBs in levels monitoring was done. The techniques, different detection matrices, and approaches to highly selective and sensitive sensing methods were reviewed. The review also summarizes the salient features and the necessity of biosensing assessments in FBs detection, and diverse immobilization techniques. Furthermore, this review defined the performance of various electrochemical sensors using different detection elements couples with nanomaterials fabricated applying different detection elements coupled with nanomaterials (metal oxide nanoparticles (NPs), metal NPs, CNT, and graphene), the factors limiting progress, and the upcoming tasks in successful aptasensor fabrication with the functionalized nanomaterials.

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.

Nanoarchitecture of graphene nanosheets decorated with NiCr layered double hydroxide for sonophotocatalytic degradation of refractory antibiotics.

Highly efficient and durable catalysts for wastewater treatment are urgently required to tackle critical environmental issues. In this regard, NiCr LDH (NC), NiCr LDH-GO (NC-GO), and NiCr LDH-rGO (NC-rGO) nanocomposites were synthesized. The results of XRD, EDX, and FTIR analyses not only explored the crystallographic and chemical structures of catalysts but also confirmed the successful synthesis. Further morphological, physical, chemical, and optical characteristics of the catalysts were evaluated more by SEM, HRTEM, BET, DRS, and XPS techniques. The as-synthesized catalysts were used for the efficient mineralization of rifadin under 50 W LED visible light irradiation and the ultrasonic power of 150 W. Amongst, 0.75 g L-1 of NC-rGO demonstrated high sonophotocatalytic efficiency (88%) in natural pH (pH = 8) of 15 mg L-1 of rifadin. The introduced system is also powerful for the decontamination of pharmaceutical-containing wastewater as well as other refractory antibiotics. Moreover, the radical trapping experiments demonstrated that the main reactive species involved in the degradation of rifadin are •OH, h+, and O2•-. The possible intermediates were thoroughly investigated using GCMS analysis. Also, NC-rGO demonstrated superior antibacterial activity in comparison with NC, NC-GO samples.

Electrochemical removal of fluoxetine via three mixed metal oxide anodes and carbonaceous cathodes from contaminated water.

In this work, the fluoxetine (FLX) removal has been studied via the anodic oxidation (AO) process. Anode electrodes were Ti/RuO2, Ti/RuO2-IrO2, and Ti/RuO2-IrO2-SnO2, and cathode electrodes were graphite and carbon nanotubes (CNTs). The performances of electrodes were compared in terms of FLX removal efficiency. As a result, Ti/RuO2-IrO2-SnO2 and CNTs were the optimal anode and cathode, respectively. The properties of the optimal electrodes were investigated using scanning electron microscopy, atomic force microscopy and X-ray diffraction spectroscopy. Cyclic voltammetry analysis was performed to study the electrochemical behavior of electrodes. The effect of current intensity (mA), initial pH, initial FLX concentration (mg/L) and process time (min) on the FLX removal efficiency was investigated and the response surface methodology was applied for the optimization of the AO process. The results showed that at current intensity, pH, initial FLX concentration and process time of 500 mA, 6, 25 mg/L and 160 min, maximum FLX removal efficiency was observed, which was 96.25%. Gas Chromatography-Mass Spectrometry (GC-MS), and total organic carbon (TOC) analysis was determined to evaluate the intermediates, and mineralization efficiency. The TOC removal efficiency was reached 81.51% after 6 h under optimal experimental conditions, indicating the successful removal of the FLX.

An electrochemical sensor for detection of trace-level endocrine disruptor bisphenol A using Mo2Ti2AlC3 MAX phase/MWCNT composite modified electrode.

Bisphenol A (BPA) is an industrially preferred material for the production of plastic and polycarbonate as well as a used material for the interior of food and beverage cans. In this study, synthesis and electrochemical sensor application of Mo2Ti2AlC3/MWCNT (multi-walled carbon nanotube) nanocomposite for BPA sensing was evaluated. Mo2Ti2AlC3 was used as MAX phase material in the design of the sensor, and MWCNT was preferred to increase conductivity and sensitivity. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to determine Mo2Ti2AlC3/MWCNT nanocomposite's electrochemical sensor performances which had LOD of 2.7 nM and LOQ of 8.91 nM in the linear working range of 0.01-8.50 µM calculated from DPV. The composite showed a single oxidation step against BPA which is diffusion-controlled and irreversible. The sensor was successfully applied for the determination of BPA in milk pack, plastic bottle, and can with recoveries ranging from 95.67% to 100.60%. In addition, sensor performance was examined through selectivity, repeatability, and reusability studies. HPLC as a standard determination method was carried out for accuracy of the voltammetric determination method in the real samples. The developed sensor could be applied to different areas from industry quality control to clinical analysis for the detection of BPA.

Tungsten disulfide (WS2)/fluorescein ratiometric fluorescent probe for detection of cefixime residues in milk.

In this research work, it has been reported a ratiometric fluorescent sensor based on tungsten disulfide quantum dots (WS2 QDs) and fluorescein for the determination of Cefixime (CEF). When excited by radiation of 400 nm wavelength the probe illustrates dual emissions centered at 460 nm and 510 nm. CEF quenches the fluorescence (FL) intensity of fluorescein (510 nm), while it doesn't affect the FL emission of WS2 QDs at 460 nm. The change in the ratio of the two peaks (F460/F510) of the prepared sensor (WS2 QDs/fluorescein) is linearly proportional to the CEF concentration in the range of 200-2.500 ng/mL with a limit of detection (LOD) of 45 ng/mL. Hence, the proposed probe can be successfully used for CEF quantification in the milk samples.

State-of-the-art progress of metal-organic framework-based electrochemical and optical sensing platforms for determination of bisphenol A as an endocrine disruptor.

Considering the low concentration levels of bisphenol compounds present in environmental, food, and biological samples, and the difficulty in analyzing the matrices, the main challenge is with the cleanup and extraction process, as well as developing highly sensitive determination methods. Recent advances in the field of metal-organic frameworks (MOFs) due to their large surface area, low weight, and other extraordinary physical, chemical, and mechanical features have made these porous materials a crucial agent in developing biosensing assays. This review focuses on MOFs across their definition, structural features, various types, synthetic routes, and their significant utilization in sensing assays for bisphenol A (BPA) determination. Additionally, recent improvements in characteristics and physio-chemical features of MOFs and their functional applications in developing electrochemical and optical sensing assays via different recognition elements for detecting BPA are comprehensively discussed. Finally, the existing boundaries of the current advances including future challenges concerning successful construction of sensing approaches by employing functionalized MOFs are addressed.

Recent trends in layered double hydroxides based electrochemical and optical (bio)sensors for screening of emerging pharmaceutical compounds.

The rapid expansion of the human population has given rise to new environmental and biomedical concerns, contributing to different advancements in the pharmaceutical industry. In the field of analytical chemistry over the last few years, layered double hydroxides (LDHs) have drawn significant attention, owing to their extraordinary properties. Furthermore, the novel advancement of LDH-based optical and electrochemical platforms to detect different pharmaceutical materials has acquired substantial attention because of their outstanding specificity, actual-time controlling, and user-friendliness. This review aims to recapitulate advanced LDHs-based optical and electrochemical sensors and biosensors to identify and measure important pharmaceutical compounds, such as anti-depressant, anti-inflammatory, anti-viral, anti-bacterial, anti-cancer, and anti-fungal drugs. Additionally, fundamental parameters, namely interactions between sensor and analyte, design rationale, classification, selectivity, and specificity are considered. Finally, the development of high-efficiency techniques for optical and electrochemical sensors and biosensors is featured to deliver scientists and readers a complete toolbox to identify a broad scope of pharmaceutical substances. Our goals are: (i) to elucidate the characteristics and capabilities of available LDHs for the identification of pharmaceutical compounds; and (ii) to deliver instances of the feasible opportunities that the existing devices have for the developed sensing of pharmaceuticals regarding the protection of ecosystems and human health at the global level.

Recent advances in the highly sensitive determination of zearalenone residues in water and environmental resources with electrochemical biosensors.

Zearalenone (ZEN), a significant class of mycotoxin which is considered as a xenoestrogen, permits, similar to natural estrogens, it's binding to the receptors of estrogen resulting in various reproductive diseases especially, hormonal misbalance. ZEN has toxic effects on human and animal health as a result of its teratogenicity, carcinogenicity, mutagenicity, nephrotoxicity, genotoxicity, and immunotoxicity. To ensure water and environmental resources safety, precise, rapid, sensitive, and reliable analytical and conventional methods can be progressed for the determination of toxins such as ZEN. Different selective nanomaterial-based compounds are used in conjunction with different analytical detection approaches to achieve this goal. The current review demonstrates the state-of-the-art advances of nanomaterial-based electrochemical sensing assays including various sensing, apta-sensing and, immunosensing studies to the highly sensitive determination of various ZEN families. At first, a concise study of the occurrence, structure, toxicity, legislations, and distribution of ZEN in monitoring has been performed. Then, different conventional and clinical techniques and procedures to sensitive and selective sensing techniques have been reviewed and the efficient comparison of them has been thoroughly discussed. This study has also summarized the salient features and the requirements for applying various sensing and biosensing platforms and diverse immobilization techniques in ZEN detection. Finally, we have defined the performance of several electrochemical sensors applying diverse recognition elements couples with nanomaterials fabricated using various recognition elements coupled with nanomaterials (metal NPs, metal oxide nanoparticles (NPs), graphene, and CNT) the issues limiting development, and the forthcoming tasks in successful construction with the applied nanomaterials.

Hard-templated metal-organic frameworks for advanced applications.

Template-directing strategies for synthesising metal-organic frameworks (MOFs) have brought about new frontiers in materials chemistry due to the possibility of applying control over crystal growth, morphology and secondarily generated pores. In particular, hard templates have resulted in performance breakthroughs in catalysis, secondary ion batteries, supercapacitance, drug delivery and molecular sieving by offering facile routes for maximising the surface areas of shape-directed MOFs. In this tutorial review, a variety of hard templates employed to direct MOFs' growth into superior nano-architectures with enhanced functionalities are discussed. Hard templates discussed here include polymers, silica nanostructures, metal oxides, layered metal hydroxides, noble metals, graphene, zeolites and MOFs themselves. These templates can be divided into three broad categories: sacrificial, semi-sacrificial and non-sacrificial templates. We elaborate on the rationale behind the choice of nanomaterials as hard templates, how hard templates direct the synthesis of MOFs, how sacrificial hard templates can be removed from the final product and what the enhanced functionalities of hard-templated MOFs are. In the case of non-sacrificial hard-templates, synergistic effects arising from the coexistence of the MOF and the hard template will also be reviewed.