Facile fabrication of ZnO nanoparticles via non-thermal plasma technique and their anti-corrosive effects on X60 API 5L steel in 1M HCl solution.

This work aims to explore the efficiency of ZnO nanoparticles synthesized via the non-thermal gliding arc discharge-assisted plasma (NT-GAD) technique for inhibiting the corrosion of X60 API 5L steel in a 1M HCl environment. The XRD pattern revealed that the ZnO nanoparticles exhibit hexagonal wurtzite structure with average particle size of ∼24 nm. UV-visible spectroscopy analysis revealed an absorption peak centering at 365 nm, corresponding to an energy band gap of 3.29 eV. SEM and TEM analysis revealed that the nanoparticles exhibit an agglomerated and irregular morphology. The corrosion inhibition of ZnO NPs was investigated via the electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization tests (PDP), while varying both concentration and temperature. The results revealed that the increase in inhibitor concentration resulted in a higher activity at ambient temperature, with an optimal efficiency of 93 % at a concentration of 100 mg/L. However, the increase in temperature remarkably reduced the inhibition efficiency, suggesting a physisorption behavior of ZnO NPs onto the steel surface. AFM and FE-SEM analysis confirmed the formation of a protective layer on the X60 API 5L steel surface. This study emphasizes the significant potential of ZnO NPs synthesized via the NT-GAD assisted plasma technique as corrosion inhibitor for X60 API 5L carbon steel in 1M HCl corrosive media.

Molecularly imprinted polymer composite membranes: From synthesis to diverse applications.

This review underscores the fundamentals of MIP-CMs and systematically summarizes their synthetic strategies and applications, and potential developments. MIP-CMs are widely acclaimed for their versatility, finding applications in separation, filtration, detection, and trace analysis, as well as serving as scaffolds in a range of analytical, biomedical and industrial contexts. Also characterized by extraordinary selectivity, remarkable sensitivity, and outstanding capability to bind molecules, those membranes are also cost-effective, highly stable, and configurable in terms of recognition and, therefore, inalienable in various application fields. Issues relating to the potential future for the paper are discussed in the last section with the focus on the improvement of resource practical application across different areas. Hence, this review can be seen as a kind of cookbook for the design and fabrication of MIP-CMs with an intention to expand the scope of their application.

Metal/Covalent Organic Framework Encapsulated Lead-Free Halide Perovskite Hybrid Nanocatalysts: Multifunctional Applications, Design, Recent Trends, Challenges, and Prospects.

Perovskites are bringing revolutionization in a various fields due to their exceptional properties and crystalline structure. Most specifically, halide perovskites (HPs), lead-free halide perovskites (LFHPs), and halide perovskite quantum dots (HPs QDs) are becoming hotspots due to their unique optoelectronic properties, low cost, and simple processing. HPs QDs, in particular, have excellent photovoltaic and optoelectronic applications because of their tunable emission, high photoluminescence quantum yield (PLQY), effective charge separation, and low cost. However, practical applications of the HPs QDs family have some limitations such as degradation, instability, and deep trap states within the bandgap, structural inflexibility, scalability, inconsistent reproducibility, and environmental concerns, which can be covered by encapsulating HPs QDs into porous materials like metal-organic frameworks (MOFs) or covalent-organic frameworks (COFs) that offer protection, prevention of aggregation, tunable optical properties, flexibility in structure, enhanced biocompatibility, improved stability under harsh conditions, consistency in production quality, and efficient charge separation. These advantages of MOFs-COFs help HPs QDs harness their full potential for various applications. This review mainly consists of three parts. The first portion discusses the perovskites, halide perovskites, lead-free perovskites, and halide perovskite quantum dots. In the second portion, we explore MOFs and COFs. In the third portion, particular emphasis is given to a thorough evaluation of the development of HPs QDs@MOFs-COFs based materials for comprehensive investigations for next-generation materials intended for diverse technological applications, such as CO2 conversion, pollutant degradation, hydrogen generation, batteries, gas sensing, and solar cells. Finally, this review will open a new gateway for the synthesis of perovskite-based quantum dots.

Effective Removal of Nile Blue Dye from Wastewater using Silver-Decorated Reduced Graphene Oxide.

Nile blue (NB) dye is a highly toxic substance that when discharged into sewage presents a significant risk to the environment and human health. Carbon-based nanomaterials, such as graphene oxide (GO), reduced graphene oxide (rGO), and their nanocomposites, offer considerable potential for eliminating hazardous pollutants from aqueous systems. In this study, we have successfully fabricated bare GO and rGO, and then, the rGO was decorated with silver (Ag) nanoparticles to develop the Ag-rGO composite. The as-prepared materials were characterized by various techniques, such as UV-visible (UV-vis) and Fourier transform infrared (FTIR) spectroscopies, X-ray diffraction (XRD), energy-dispersive X-ray (EDX), and scanning electron microscopy (SEM) to elucidate their structure, morphology, and chemical composition. The pollutant removal performance of the as-prepared materials was evaluated through a batch approach under the effect of various experimental variables for removal of NB dye from wastewater. As obvious, the Ag-rGO composite revealed exceptional performance for NB dye removal from wastewater, with a maximum removal percentage of 94% within 60 min, which is remarkably higher than those of the rGO (i.e., 59%) and GO (i.e., 22%), under the same experimental conditions. The adsorption data was analyzed with thermodynamics, isotherms, and kinetics models to better understand the physicochemical mechanisms driving the effective removal of the NB dye. The results reveal that Ag-rGO nanocomposite exhibit excellent adsorption ability as well as favorable thermodynamic and kinetic parameters for NB dye removal. It was also found that the presence of light enhanced the adsorptive removal of NB while using Ag-rGO as an adsorbent. The present study noted significant reusability of the Ag-rGO nanocomposite, likely due to minimal Ag leaching and/or the robust stability of the Ag-rGO. It is suggested that Ag-rGO-based hybrid materials could serve as promising candidates for efficiently adsorbing and catalytically removing various toxic pollutants from wastewater.

Environmental Implications Associated with the Development of Nanotechnology: From Synthesis to Disposal.

Nanotechnology remains under continuous development. The unique, fascinating, and tunable properties of nanomaterials make them interesting for diverse applications in different fields such as medicine, agriculture, and remediation. However, knowledge about the risks associated with nanomaterials is still poorly known and presents variable results. Furthermore, the interaction of nanomaterials with biological systems and the environment still needs to be clarified. Moreover, some issues such as toxicity, bioaccumulation, and physicochemical transformations are found to be dependent on several factors such as size, capping agent, and shape, making the comparisons even more complex. This review presents a comprehensive discussion about the consequences of the use and development of nanomaterials regarding their potential risks to the environment as well as human and animal health. For this purpose, we reviewed the entire production chain from manufacturing, product development, applications, and even product disposal to raise the important implications at each stage. In addition, we present the recent developments in terms of risk management and the recycling of nanomaterials. Furthermore, the advances and limitations in the legislation and characterization of nanomaterials are also discussed.

Efficient Mesoporous MgO/g-C3N4 for Heavy Metal Uptake: Modeling Process and Adsorption Mechanism.

Removing toxic metal ions arising from contaminated wastewaters caused by industrial effluents with a cost-effective method tackles a serious concern worldwide. The adsorption process onto metal oxide and carbon-based materials offers one of the most efficient technologies adopted for metal ion removal. In this study, mesoporous MgO/g-C3N4 sorbent is fabricated by ultrasonication method for the uptake Pb (II) and Cd (II) heavy metal ions from an aqueous solution. The optimum conditions for maximum uptake: initial concentration of metal ions 250 mg g-1, pH = 5 and pH = 3 for Pb++ and Cd++, and a 60 mg dose of adsorbent. In less than 50 min, the equilibrium is reached with a good adsorption capacity of 114 and 90 mg g-1 corresponding to Pb++ and Cd++, respectively. Moreover, the adsorption isotherm models fit well with the Langmuir isotherm, while the kinetics model fitting study manifest a perfect fit with the pseudo-second order. The as fabricated mesoporous MgO/g-C3N4 sorbent exhibit excellent Pb++ and Cd++ ions uptake and can be utilized as a potential adsorbent in wastewater purification.

The Cytotoxic Effectiveness of Thiourea-Reduced Graphene Oxide on Human Lung Cancer Cells and Fungi.

This study demonstrated the effective reduction of graphene oxide (GO) by employing thiourea as a reducing and stabilizing agent. Two fungi (Aspergillus flavus and Aspergillus fumigatus) were used for anti-fungal assay. Cell viability, cell cycle analysis, DNA fragmentation, and cell morphology were assessed to determine the toxicity of thiourea-reduced graphene oxide (T-rGO) on human lung cancer cells. The results revealed that GO and T-rGO were hazardous to cells in a dose-dependent trend. The viability of both A. fumigatus and A. flavus was affected by GO and T-rGO. The reactive oxygen species produced by T-rGO caused the death of A. flavus and A. fumigatus cells. This study highlighted the effectiveness of T-rGO as an antifungal agent. In addition, T-rGO was found to be more harmful to cancer cells than GO. Thus, T-rGO manifested great potential in biological and biomedical applications.

Investigation of the survival viability of cervical cancer cells (HeLa) under visible light induced photo-catalysis with facile synthesized WO3/ZnO nanocomposite.

The photo catalytic degradation, a proven chemical process used for the decontamination of organic/inorganic pollutants and microorganisms in water was implemented. In this work for the selective killing of cervical cancer cells (HeLa cells) by using nano-composite of ZnO (Zinc Oxcide), WO3 (tungsten oxide) and (n-WO3/ZnO) as a photo-catalyst under the irradiation of visible light. All the three nanostructured semiconducting materials (WO3, ZnO and n-WO3/ZnO) were synthesized by facile chemical precipitation method and their morphological and optical characterization studies were carried out to elucidate the observed enhancement in the photo-catalytic killing of HeLa cancer cells with n-WO3/ZnO as a photo-catalyst. After 60 min of photo-catalytic reaction with n-WO3/ZnO as a photo-catalyst, a survival viability of HeLa cancer cells as low as 15% was achieved (nearly 85% of killing), as compared to 65% of HeLa cancer cell survival viability (nearly 35% of killing) with individual use of WO3 and ZnO as photo-catalysts under the same irradiation and experimental conditions. This improved photo-catalytic killing of HeLa cancer cells using n-WO3/ZnO in the visible spectral region is attributed to the enhanced visible light absorption and reduced electron hole recombination, characteristically brought about in the n-WO3/ZnO composite material. As photo-catalytic killing of the cancer cells can be selective, localized and reasonably efficient, in principle, this method can be considered as a non-invasive targeted treatment option for killing any type of cancer cells. HeLa cells, in particular are the cervical cancer cell and the tumors in and around cervix, containing HeLa cells can be non-surgically accessed and photo-catalytically treated with appropriate photo-catalyst and light source.

Photo-catalytic Killing of HeLa Cancer Cells Using Facile Synthesized Pure and Ag Loaded WO3 Nanoparticles.

Chemotherapy, the most commonly used therapeutic method for cancer, has the inherent constraint of low bioavailability. A number of physical cancer therapeutic treatments like radiation, ultrasound, photo-acoustic/photo thermal, microwave therapies are based on locating the afflicted sites with the help of imaging, but the serious drawbacks of these treatment options are that they damage the neighboring normal tissues and/or induce undesired cancer metastasis. In addition, these methods of treatment are very expensive and not in the reach of a common man especially in the developing countries. Therefore, innovative, less invasive and cost effective treatment methods with the help of less toxic drugs have been sought for treating cancer. In this work, photo-catalytic method of killing cancer cells, using the nanostructured silver loaded tungsten oxide (Ag/WO3) as photo-catalysts, in conjunction with broadband UV radiation is presented. Ag/WO3with two different mass ratios of Ag and WO3 (1% Ag/WO3 and 3% Ag/WO3) were synthesized, characterized and these nanostructured materials served as photo-catalysts in the process of killing cancer cells by photo-catalytic method. The advantage of loading Ag in WO3 is quite evident from the observed increase in the photo-catalytic killing of the HeLa cells. This photo-catalytic enhancement was effectively caused by the development of Schottky junction between Ag in WO3, which led to a substantial inhibition of photo-generated charge recombination and also by the stimulation of surface plasmon resonance in silver nanoparticles, which led to the enhanced visible light absorption by the material.