Facile fabrication of amorphous Al/Fe based metal-organic framework as effective heterogeneous fenton catalyst for environmental remediation.

This study presents a facile preparation and durable amorphous Fe and Al-based MOF nanoplate (AlFe-BTC MOFs) catalyst with notable stability in Fenton reactions. Rigorous characterization using XRD, HR-TEM, and BET confirms the amorphous nature of the synthesized AlFe-BTC MOFs, revealing mesopores (3.4 nm diameter), a substantial surface area (232 m2/g), and a pore volume of 0.69 cc/g. XPS analysis delineates distinct Al2p and Fe2p binding energy values, signifying specific chemical bonding. FE-SEM elemental mapping elucidates the distinctive distribution of Fe and Al within the framework of AlFe-BTC MOFs. In catalytic activity testing, the amorphous AlFe-BTC MOFs exhibited outstanding performance, achieving complete degradation of Methylene blue (MB) dye and 78% TOC removal over 45 min of treatment under mild reaction conditions. The catalyst's durability was assessed, revealing about 75% TOC removal and complete dye decomposition over five successive recycles, with less than 1 mg/L of Fe and Al leaching. UV-Vis spectra revealed the destruction of MB dye over multiple recycling studies. Based on this finding, the amorphous AlFe-BTC MOF nanoplates emerge as a promising solution for efficient dye removal from industrial wastewater, underscoring their potential in advanced environmental remediation processes.

Graphene materials in pollution trace detection and environmental improvement.

Water scarcity is a pressing issue experienced in numerous countries and is expected to become increasingly critical in the future. Anthropogenic activities such as mining, agriculture, industries, and domestic waste discharge toxic contaminants into natural water bodies, causing pollution. Addressing these environmental crises requires tackling the challenge of removing pollutants from water. Graphene oxide (GO), a form of graphene functionalized with oxygen-containing chemical groups, has recently garnered renewed interest due to its exceptional properties. These properties include a large surface area, mechanical stability, and adjustable electrical and optical characteristics. Additionally, surface functional groups like hydroxyl, epoxy, and carboxyl groups make GO an outstanding candidate for interacting with other materials or molecules. Because of its expanded structural diversity and enhanced overall properties, GO and its composites hold significant promise for a wide range of applications in energy storage, conversion, and environmental protection. These applications encompass hydrogen storage materials, photocatalysts for water splitting, the removal of air pollutants, and water purification. Serving as electrode materials for various lithium batteries and supercapacitors. Graphene-based materials, including graphene, graphene oxide, reduced graphene oxide, graphene polymer nanocomposites, and graphene nanoparticle metal hybrids, have emerged as valuable tools in energy and environmental remediation technologies. This review article provides an overview of the significant impact of graphene-based materials in various areas. Regarding energy-related topics, this article explores the applications of graphene-based materials in supercapacitors, lithium-ion batteries, and catalysts for fuel cells. Additionally, the article investigates recent advancements in detecting and treating persistent organic pollutants (POPs) and heavy metals using nanomaterials. The article also discusses recent developments in creating innovative nanomaterials, nanostructures, and treatment methods for addressing POPs and heavy metals in water. It aims to present the field's current state and will be a valuable resource for individuals interested in nanomaterials and related materials.

A novel approach to environmental pollution management/remediation techniques using derived advanced materials.

The carbon dioxide (CO2) crisis is one of the world's most urgent issues. Meeting the worldwide targets set for CO2 capture and storage (CCS) is crucial. Because it may significantly reduce energy consumption compared to traditional amine-based adsorption capture, adsorption dependant CO2 capture is regarded as one of the most hopeful techniques in this paradigm. The expansion of unique, critical edge adsorbent materials has received most of the research attention to date, with the main objective of improving adsorption capacity and lifespan while lowering the temperature of adsorption, thereby lowering the energy demand of sorbent revival. There are specific materials needed for each step of the carbon cycle, including capture, regeneration, and conversion. The potential and efficiency of metal-organic frameworks (MOFs) in overcoming this obstacle have recently been proven through research. In this study, we pinpoint MOFs' precise structural and chemical characteristics that have contributed to their high capture capacity, effective regeneration and separation processes, and efficient catalytic conversions. As prospective materials for the next generation of energy storage and conversion applications, carbon-based compounds like graphene, carbon nanotubes, and fullerenes are receiving a lot of interest. Their distinctive physicochemical characteristics make them suitable for these popular study topics, including structural stability and flexibility, high porosity, and customizable physicochemical traits. It is possible to precisely design the interior of MOFs to include coordinatively unsaturated metal sites, certain heteroatoms, covalent functionalization, various building unit interactions, and integrated nanoscale metal catalysts. This is essential for the creation of MOFs with improved performance. Utilizing the accuracy of MOF chemistry, more complicated materials must be built to handle selectivity, capacity, and conversion all at once to achieve a comprehensive solution. This review summarizes, the most recent developments in adsorption-based CO2 combustion capture, the CO2 adsorption capacities of various classes of solid sorbents, and the significance of advanced carbon nanomaterials for environmental remediation and energy conversion. This review also addresses the difficulties and potential of developing carbon-based electrodes for energy conversion and storage applications.

A review on bismuth-based nanocomposites for energy and environmental applications.

Bismuth, a heavy metal which is found to be inexpensive and at a reduced cost, is utilized in the synthesis of different nanomaterials with novel structure, remarkable physical and chemical properties, adjustable bandgap, notable efficiency for photothermal conversion. These characteristics have made this element desirable for various applications such as storage and conversion of energy, electronics, sensors, photocatalysis, and other biomedical applications. These review papers are the vital points for the students, this report guides them to the research papers which focus on the impressive development in the area of bismuth and similar nanostructures. The purpose of the present review is to discuss the various synthesis routes of bismuth-based nanomaterials along with green synthesis, different nanostructures of bismuth, their significant properties, diverse applications and directions for the upcoming research. Therefore, with these different tuneable synthesis methods of bismuth-based nanomaterials combined with their novel properties, would elucidate on the future devices based on various nanostructures of bismuth.

CuO-NiO binary transition metal oxide nanoparticle anchored on rGO nanosheets as high-performance electrocatalyst for the oxygen reduction reaction.

To replace the existing noble-metal-based catalysts, developing highly efficient, stable electrocatalysts for oxygen reduction reactions for the increased current generation with lower overpotential is a demanding undertaking. In the present work, CuO-NiO/rGO nanocomposites were prepared using simple, cost-effective Co-precipitation methods. They act as highly effective electrocatalysts for oxygen reduction reactions in an alkaline medium. The structural characterizations demonstrate that prepared nanoparticles (≈13 nm) are tightly and effectively organized on reduced graphene oxide sheets. The electrochemical properties of the CuO, NiO nanoparticles and CuO-NiO, CuO-NiO/rGO nanocomposites were investigated. The results of the CuO-NiO/rGO nanocomposites revealed the high current density (2.9 × 10-4 mA cm-2), lower Tafel slope (72 mV dec-1) and low hydrogen peroxide yield (15%) when compared to other prepared materials (CuO, NiO, and CuO-NiO). The reduced graphene oxide increases an electron transfer during the ORR process, while the CuO-NiO has variable oxidation states that promote electro-rich features. With the combination of CuO-NiO and rGO, the hybrid electrocatalysts specific surface area and charge transfer rate drastically increase. The investigations of the rotating ring-disk electrodes experiments indicate that the oxygen reduction process takes place on CuO-NiO/rGO through an efficient four-electron pathway. Our results propose a new approach to creating highly efficient and long-lasting electrocatalysts.

Electrocatalytic detection of noxious antioxidant diphenylamine in fruit samples with support of Cu@nanoporous carbon modified sensor.

Herein, the facile synthesis of copper(II) and benzene-1,3,5-tricarboxylate (Cu-BTC) and copper nanoporous carbon (Cu@NPC) for the electrochemical detection of diphenylamine (DPA) was systematically investigated. The Cu-BTC and Cu@NPC materials structural, morphological, and thermal stability were evaluated and confirmed using FE-SEM, HR-TEM, XRD, FT-IR, and TGA. The electrocatalytic behavior of sensor materials was examined by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). It is presumed that the structural stability and synergic effect exhibited in Cu@NPC are favorable for enhanced sensitivity and selectivity towards the detection of DPA. The Cu@NPC exhibited a wide linear range (0.09-396.82 µM) and the lowest limit of detection (5 nM). Furthermore, the real sample analysis of the sensor for the detection of DPA in apples and pears confirms its potential capability in practical application.

Enhanced photocatalytic activities of facile auto-combustion synthesized ZnO nanoparticles for wastewater treatment: An impact of Ni doping.

In the current work, we present the facile one-pot synthesis of 0.0, 0.5, 1.0, 2.0 and 3.0 wt% of Ni doped ZnO nanoparticles (Ni:ZnO NPs) through combustion route at 550 °C. Structural and vibrational studies approve the synthesis of monophasic hexagonal Ni:ZnO NPs. The crystallite size was calculated to be in the range of 36-60 nm for pure and doped samples. The composition of all elements in the final product along with their homogeneity, was approved through EDX/FESEM e-mapping analysis. The morphology and phase confirmation of the prepared samples was investigated through FESEM and TEM/HRTEM analyses. TEM/HRTEM study shows that the size of grains is within the range of 100 nm and grown along the c-axis as the lattice spacing is found ∼2.6005 Å. Diffused reflectance study was used to estimate the energy gap for all samples and found to reduce from 3.287 eV for pure to 3.258 eV for 3.0 wt% Ni doping. From an applications point of view, the photocatalytic performance of Ni:ZnO NPs was studied, and with 3.0 wt% of Ni doping in ZnO the degradation of methylene blue (MB) and tetracycline (TCN) pollutants were found to be remarkably improved.

Morphology-dependent MoO3/Ni-F nanostructures with enhanced electrochemical hydrogen peroxide detection.

The present report investigates the various MoO3 morphologies prepared via different approaches such as morphologies are cubic sheet, ribbon, and hexagonal sheet. These prepared nanostructures are modified as a MoO3/Ni-F electrode used to detect hydrogen peroxide (H2O2). The influence of the morphology on the microstructural, morphological, electronic state, optical and electrochemical properties of MoO3 nanostructures are systematically studied. The recorded XRD spectra confirmed that the good crystalline nature with the orthorhombic crystal structure. The FESEM analysis shows that preparation approaches strongly influenced the MoO3 morphology. The elemental mapping and XPS analysis confirm the formation of MoO3. The obtained optical band gap values show that the MoO3 morphology-based bandgap values are 3.38, 3.17, and 2.94 eV. The modified MoO3/Ni-F electrode electrochemical impedance spectra show the CP-MoO3 has good conductivity. Moreover, the CP-MoO3/Ni-F electrode has a wide detection window, long-term stability, reproducibility, and a low detection limit is 1.2 µM. Hence, the CP-MoO3/Ni-F electrode electrochemical results suggest that the modified electrode has offered a good matrix for toxic contaminants sensing applications.

Ultrasensitive electrochemical detection of furazolidone in biological samples using 1D-2D BiVO4@MoS2 hierarchical nano-heterojunction composites armed electrodes.

In this work, the hydrothermally synthesized of BiVO4@MoS2 hierarchical nano-heterojunction composite is employed as a novel electrocatalyst for electrochemical sensing of Furazolidone (FZE) drug by modifying the glassy carbon electrodes (GCE). The Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and transmission electron microscopy are used to thoroughly investigate the functional groups, vibrational modes, crystal structure, elemental composition and surface topography of the heterojunction composite. The physical characterization results revealed the successful construction of 1D-2D BiVO4@MoS2 hierarchical nano-heterojunction composite. When these unique architectures are reinforced on GCE surface, we achieved an enhanced electroactive surface area of 0.154 cm2. The electrochemical performance of 1D-2D BiVO4@MoS2 is examined though cyclic voltammetry and differential pulse voltammetry (DPV) analysis. The BiVO4@MoS2 composites exhibited an excellent electrocatalytic activity in sensing of FZE with superior linear detection ranges of 0.01-14 and 14-614 µM. The limit of detection (LOD) of the BiVO4@MoS2 based sensor is determined to be 2.9 nM which is far superior than other reported FZE sensors. Consequently, it is evident from the investigation that the BiVO4@MoS2 based FZE sensor can be recommended for analyzing real time samples like human urine and blood serum with appreciable recovery.

Fast-response liquid crystal lens with doping of organic N-benzyl-2-methyl-4-nitroaniline.

In this study, a large-aperture hole-patterned liquid crystal (LHLC) lens was prepared from a mixture of nematic liquid crystal (NLC, E7) and organic material (N-benzyl-2-methyl-4-nitroaniline, BNA). The electro-optic properties of doped and undoped samples were measured, compared, and analyzed. The doped sample exhibited a response time that was ∼6 times faster than that of the undoped sample because BNA doping decreased the rotational viscosity of the NLC. BNA dopant effectively suppressed the RMS error of LHLC lens addressed at the high voltage. Furthermore, the BNA dopant revealed a considerable absorbance for short wavelengths (< 450 nm), automatically providing the LHLC lens with a blue light filtering function for ophthalmic applications.