Covalent organic frameworks (COFs) are class of porous coordination polymers made up of organic building blocks joined together by covalent bonding through thermodynamic and controlled reversible ...polymerization reactions. This review discussed versatile applications of COFs for remediation of wastewater containing dyes, emphasizing the advantages of both pristine and modified materials in adsorption, membrane separation, and advanced oxidations processes. The excellent performance of COFs towards adsorption and membrane filtration has been centered to their higher crystallinity and porosity, exhibiting exceptionally high surface area, pore size and pore volumes. Thus, they provide more active sites for trapping the dye molecules. On one hand, the photocatalytic performance of the COFs was attributed to their semiconducting properties, and when coupled with other functional semiconducting materials, they achieve good mechanical and thermal stabilities, positive light response, and narrow band gap, a typical characteristic of excellent photocatalysts. As such, COFs and their composites have demonstrated excellent potentialities for the elimination of the dyes.
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•Dyes as hazardous pollutants in wastewater.•Recent advancements in COFs applications for dyes remediation.•Perspectives and challenges of COFs for dyes remediation.
The presence of Methyl Orange, a hazardous organic compound typically found in industrial wastewater, presents a significant environmental challenge, necessitating the development of effective ...strategies for its removal to mitigate adverse impacts on aquatic ecosystems and human health. In this work, we utilized 60-watt continuous-wave (CW) and high-power CO2 laser with 10.6 μm wavelength to synthesize Zinc Oxide nanoparticles (ZnO NPs) doped with 1% Cerium (Ce) as photocatalyst at standard laboratory conditions through Laser-Assisted Chemical Bath Synthesis (LACBS) technique. The synthesized nanostructures were thoroughly characterized using UV–vis spectroscopy, field-emission scanning electron microscopy (FESEM), and X-ray diffraction (XRD) techniques. Subsequently, their efficiency in degrading Methyl Orange (MO) dye was evaluated under UV and sunlight irradiation. The findings revealed that the 1% Ce-doped ZnO sample exhibited enhanced photocatalytic efficiency under both UV and sunlight irradiation, as well as active adsorption capabilities in the absence of light. Notably, the most effective photodegradation performance was achieved under solar radiation, with an impressive 95% of MO dye degradation observed after just 90 min of exposure.
Frequent detection of terbutaline in wastewater highlights its potential risks to human health associated in the environment. Exposure to terbutaline through contaminated water sources or food chain ...have adverse effects to human health. This work emphasized on the removal of terbutaline from wastewater using adsorption technology. Mechanochemically synthesized Cu(INA)2 metal-organic frameworks (MOFs) and its magnetic composite (Cu(INA)2-MOF@Fe3O4) are designed with higher specific surface areas and tailored features to accommodate the molecular size and structure of terbutaline. Thus, batch experiment has been conducted using the Cu(INA)2-MOF and Cu(INA)2-MOF@Fe3O4 for the terbutaline adsorption. The adsorption efficiency achieved by the MOFs was 91.8% and 99.3% for the Cu(INA)2-MOF and Cu(INA)2-MOF@Fe3O4 respectively. The optimum for the adsorption study included terbutaline concentration of 40 mg/L, adsorbent dose of 5 mg/L, pH of 11, temperature of 25 °C and equilibrium time of 40 min. The kinetics and isotherms have been described by pseudo-second order and Langmuir models, while the thermodynamics revealed the exothermic and spontaneous nature of the process. The promising performance of the MOFs is manifested on the ease of regeneration and reusability, achieving adsorption efficiency of 85.0% and 94.7% by the Cu(INA)2-MOF and Cu(INA)2-MOF@Fe3O4, respectively at five consecutive cycles. The higher performance of the MOFs demonstrates their excellent potentialities for the terbutaline adsorption from the aqueous solution.
•Effective mechanochemical synthesis of Cu(INA)2-MOFs and Cu(INA)2-MOFs@Fe2O3.•High performance of MOFs to remove terbutaline β-agonists via adsorption process.•Optimization of adsorptive parameters to enhance removal of terbutaline β-agonists.•Kinetic, isotherm, and thermodynamic studies of terbutaline β-agonists adsorption.•Facile regeneration and effective reusability of spent MOFs for recyclable use.
Environmental pollution has been increasing since last decade due to increasing industrialisation and urbanisation. Various kinds ofenvironmental pollutants including carbon dioxide (CO2), dyes, ...pharmaceuticals, phenols, heavy metals along with many organic and inorganic species have been discovered in the various environmental compartments which possess harmful impacts tox human health, wildlife, and ecosystems. Thus, various efforts have been made through regulations, technological advancements, and public awareness campaigns to reduce the impact of the pollution. However, finding suitable alternatives to mitigate their impacts remained a challenge. Metal-organic frameworks (MOFs) are one of the advanced materials with unique features such as high porosity and stability which exhibit versatile applications in environmental remediation. Their composites with titanium oxide nanoparticles (TiO2) have been discovered to offer potential feature such as light harvesting capacity and catalytic activity. The composite integration and properties have been confirmed through characterization using surface area analysis, scanning electron/transmission electron microscopy, atomic force microscopy, fourier transformed infrared spectroscopy, X-ray diffraction analysis, X-ray photoelectron spectroscopy, thermogravimetric analysis, and others. Thus, this work rigorously discussed potential applications of the MOF@TiO2 nanomaterials for the CO2 capture and effective utilization in methanol, ethanol, acetone, acetaldehyde, and other useful products that served as fuel to various industrial processes. Additionally, the work highlights the effective performance of the materials towards photocatalytic degradation of both organic and inorganic pollutants with indepth mechanistic insights. The article will offer significant contribution for the development of sustainable and efficient technologies for the environmental monitoring and pollution mitigation.
ZnO microrods (ZnO-MRs) have unique properties that make them highly attractive for applications such as optoelectronics, electronics, and sensors. This work demonstrates the successful synthesis of ...high-quality ZnO-MRs using a laser-assisted chemical bath deposition method. The optimal growth temperature for high-quality ZnO-MRs was found to be 61.10 °C, considerably lower than that required for conventional chemical methods. Various characterization techniques, including X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy Dispersive X-ray (EDX), and UV-Vis spectrometry, confirmed the structural and optical properties of the synthesized ZnO-MRs. The UV detection potentialities of the fabricated ZnO-MRs were investigated. All samples exhibited good UV detection capabilities with the sample grown at 61.10 °C showing the best performance with fast response and recovery times of 1.260 s and 1.398 s, respectively. These findings hold immense potential for developing more efficient methods for synthesizing ZnO-MRs for use in various applications.
This study introduces a novel nanocomposite coating composed of PANI/CeO2 nanocomposite films, aimed at addressing corrosion protection needs. Analysis through FTIR spectra and XRD patterns confirms ...the successful formation of the nanocomposite films. Notably, the PANI/CeO2 nanocomposite films exhibit a hydrophilic nature. The bandgap energy of the PANI composite film is measured to be 3.74 eV, while the introduction of CeO2 NPs into the PANI matrix reduces the bandgap energy to 3.67 eV. Furthermore, the electrical conductivity of the PANI composite film is observed to be 0.40 S·cm−1, with the incorporation of CeO2 NPs leading to an increase in electrical conductivity to 1.07 S·cm−1. To evaluate its efficacy, electrochemical measurements were conducted to assess the corrosion protection performance. Results indicate a high protection efficiency of 92.25% for the PANI/CeO2 nanocomposite film.
Laser-induced breakdown spectroscopy (LIBS) is a technique that allows quantitative and qualitative analysis of many materials. In this study, the LIBS analysis options for strontium mixture powders ...is expanded by increasing the number of usable strontium atomic transitions to avoid incorrect results due to spectral congestion or high strontium concentrations. The research employs double-sided tape affixed to a glass slide to hold the sample where the powder is poured onto one surface of the tape and excess dust that has not adhered is removed. This method minimizes the sample quantity needed and keeps the sample on the slide during experimentation, which also reduces costs. Herein, LIBS was used to detect and quantify the level of metal concentrations in used engine oil samples to provide valuable information about the composition of the selected material in a liquid sample. Data were obtained using multivariate analysis to develop calibration curves using LIBS spectra, which was employed for the quantification of the elements Al, Ca, Fe, Mg, and Mn. The relationship between the peak intensity of the metals in new engine oil samples and the metal concentrations in used engine oil samples were analyzed to minimize the matrix effect and the interference of element lines after which the atomic emission observed in LIBS spectra of used engine oil and new engine oil were compared. C2 molecular band emissions were also used to determine the degree of the engine oil degradation. Next, calibration models were developed for samples with high species concentrations. A partial least squares regression model was developed for calibration models to overcome matrix effect problems of some lines of each metal. This research successfully used the LIBS technique to determine the degree of engine oil degradation. This study established that used engine oil analysis using the LIBS technique can be utilized to maintain engines in good condition and to prevent engine failure. This paper presents the key findings and conclusions regarding the application of LIBS. Finally, although this technique shows many benefits and reliable results, challenges remain in terms of matrix effects, spectral pre-processing, model calibration, and instrumentation.
The present study employs a cost-effective laser ablation technique in combination with the RF sputtering method to successfully synthesize silver nanoparticles encapsulated by zinc oxide on a ...silicon (Si) substrate. This synthesis approach aims to enhance the efficiency of photodetector devices while concurrently reducing material expenses, thereby promoting advancements in photodetector applications. The incorporation of various plasmonic nanoparticles (NPs) into the photodetector's architecture is demonstrated as a means to substantially improve the photoresponse of UV photodetectors. Three distinct samples, denoted as AgNPs/Si, AgNPs/ZnO/Si, and ZnO/AgNPs/Si, underwent comprehensive analysis and characterization of their morphological attributes, crystal structures, elemental composition, and optical properties. The UV photodetection efficacy of these samples was evaluated by subjecting them to 385 nm UV light at different bias voltages. The current-voltage (I-V) characteristics of the ZnO/AgNPs/Si photodetector revealed significantly enhanced conductivity in comparison to the AgNPs/Si and AgNPs/ZnO/Si counterparts. Remarkably, the ZnO/AgNPs/Si photodetector exhibited the highest responsivity value of 132 A/W, accompanied by quantum efficiency of 429.88, sensitivity of 31,400%, gain of 315, detectivity of 18 × 1010 Jones, and a noise equivalent power (NEP) of 0.556 × 10–13 W. These findings underscore the efficacy of our innovative broadband photodetector, highlighting its potential for practical implementation. This research offers valuable insights into the enhancement of photodetector performance and its applicability in real-world scenarios.
•Synthesized AgNPs encapsulated by ZnO on a Si substrate.•Plasmonic NP are incorporated to enhance the response of UV photodetectors.•UV detection efficacy is evaluated under 385 nm UV light at different bias voltages.•The ZnO/AgNPs/Si photodetector demonstrated enhanced conductivity.
Laser-induced breakdown spectroscopy (LIBS) is a technique that allows quantitative and qualitative analysis of many materials. In this study, the LIBS analysis options for strontium mixture powders ...is expanded by increasing the number of usable strontium atomic transitions to avoid incorrect results due to spectral congestion or high strontium concentrations. The research employs double-sided tape affixed to a glass slide to hold the sample where the powder is poured onto one surface of the tape and excess dust that has not adhered is removed. This method minimizes the sample quantity needed and keeps the sample on the slide during experimentation, which also reduces costs.Herein, LIBS was used to detect and quantify the level of metal concentrations in used engine oil samples to provide valuable information about the composition of the selected material in a liquid sample. Data were obtained using multivariate analysis to develop calibration curves using LIBS spectra, which was employed for the quantification of the elements Al, Ca, Fe, Mg, and Mn. The relationship between the peak intensity of the metals in new engine oil samples and the metal concentrations in used engine oil samples were analyzed to minimize the matrix effect and the interference of element lines after which the atomic emission observed in LIBS spectra of used engine oil and new engine oil were compared. C2 molecular band emissions were also used to determine the degree of the engine oil degradation. Next, calibration models were developed for samples with high species concentrations. A partial least squares regression model was developed for calibration models to overcome matrix effect problems of some lines of each metal.This research successfully used the LIBS technique to determine the degree of engine oil degradation. This study established that used engine oil analysis using the LIBS technique can be utilized to maintain engines in good condition and to prevent engine failure. This paper presents the key findings and conclusions regarding the application of LIBS. Finally, although this technique shows many benefits and reliable results, challenges remain in terms of matrix effects, spectral pre-processing, model calibration, and instrumentation.
This study introduces a novel nanocomposite coating composed of PANI/CeO
nanocomposite films, aimed at addressing corrosion protection needs. Analysis through FTIR spectra and XRD patterns confirms ...the successful formation of the nanocomposite films. Notably, the PANI/CeO
nanocomposite films exhibit a hydrophilic nature. The bandgap energy of the PANI composite film is measured to be 3.74 eV, while the introduction of CeO
NPs into the PANI matrix reduces the bandgap energy to 3.67 eV. Furthermore, the electrical conductivity of the PANI composite film is observed to be 0.40 S·cm
, with the incorporation of CeO
NPs leading to an increase in electrical conductivity to 1.07 S·cm
. To evaluate its efficacy, electrochemical measurements were conducted to assess the corrosion protection performance. Results indicate a high protection efficiency of 92.25% for the PANI/CeO
nanocomposite film.
