Synthesis, characterization and adsorption optimization of bimetallic La-Zn metal organic framework for removal of 2,4-dichlorophenylacetic acid.

To eliminate the hazardous pesticide 2,4-dichlorophenylacetic acid (2,4-D) through aqueous solutions, stacked nanorods known as hetero bimetallic organic frameworks (MOFs) of 2-methyl imidazole based on lanthanum and zinc are created. The research's convincing discoveries displayed that La/Zn-MOF is an actual adsorbent for the removal of 2,4-D through aqueous solutions. The La/Zn-MOF was investigated using a variability of techniques, with scanning electron microscope (SEM), powered X-ray diffraction (PXRD), and Brunauer-Emmett-Teller (BET) investigation. La/Zn-MOF has a significant pore capacity of 1.04 cm³/g and a comparatively large surface area of 897.69 m2/g. Our findings, which are quite intriguing, demonstrate that adsorption behavior is pointedly wedged by variations in pH. A pH 6 dose of 0.02 g was shown to be the optimal setting for the greatest capacity for adsorption. Because adsorption is an endothermic process, temperature variations affect its capability. The adsorption method was fit both isothermally and kinetically using the Langmuir isotherm classical. It was created that the entire process made use of a chemisorption mechanism. Solution pH, temperature, adsorbent dosage, and time were all improved using the Box-Behnken design (BBD) and Response Surface Methodology (RSM). We were able to accurately calculate the values of ΔHo, ΔSo, and ΔGo for 2,4-D by following the guidelines. These results demonstrated the spontaneous and endothermic character of the adsorption procedure employing La/Zn-MOF as an adsorbent. Adsorption-desorption cycles can be carried out up to five times. With the synthesized La/Zn-MOF adsorbent due to its exceptional reusability. Many processes, such π-π interaction, pore filling, H-bonding, or electrostatic contact, were postulated to explain the connection between La/Zn-MOF and 2,4-D after extra research to appreciate well the link was conducted. This is the first study to demonstrate the effectiveness of utilizing La/Zn-MOF as an adsorbent to eliminate 2,4-D from wastewater models. The results display that a pH of 6 is required to achieve the maximal 2,4-D adsorption capability on La/Zn-MOF, which is 307.5 mg/g.

Facile synthesis of new metal-organic framework/chitosan composite sponge for Hg(II) removal: Characterization, adsorption efficiency, and optimization using Box-Behnken design.

The objective of this research was to develop a novel adsorbent to eliminate mercury (Hg(II)) from water. A unique citrate-crosslinked La-MOF/citrate crosslinked chitosan composite sponge (La-MOF@CSC composite sponge) was successfully synthesized in an acidic environment using a one-step technique. Modifying the composition of adsorbent materials is a commonly employed strategy to enhance adsorption capacity, particularly for materials composed of metal-organic frameworks. The study investigated the impact of the composite sponge on the adsorption and removal of Hg(II). The composite sponge exhibited a maximum adsorption capacity (qmax) for Hg(II) at 765.22 mg/g and an impressive high surface area of 1208 m2/g. Various factors influencing the adsorption capacity were taken into account in this study. The adsorption isotherm and kinetics were modeled using Langmuir and pseudo-second-order equations, respectively. Consistent with thermodynamics, the adsorption process was identified as spontaneous and endothermic. The quantities of adsorbed substances increased with rising temperature. The La-MOF@CSC composite sponge demonstrated the ability to be reused up to five times with satisfactory efficiency, retaining its chemical composition and exhibiting similar XRD and XPS data before and after each reuse. The interaction between heavy metals and the La-MOF/CSC composite sponge was examined. Optimization of the adsorption outcomes was conducted using the Box-Behnken design (BBD).

Adsorption of Azorubine E122 dye via Na-mordenite with tryptophan composite: batch adsorption, Box-Behnken design optimisation and antibacterial activity.

In the current investigation, we have reported on the preparation of Na-Mordenite (MOR) modified by tryptophan (MOR-NH2) nanocomposite was synthesized and characterized using FT-IR, XRD, SEM, XPS, and BET that represented that the MOR-NH2 has high surface area 288 m2/g and pore volume 0.38 cm3/g. This composite represented high efficiency in removal of food dye Azorubine (E122) was 1043 mg/g. Study all the factors that affected on the adsorption such as pH, dose, salinity, E122 dye concentration as well as study the adsorption isotherm models that represented that was fitted to Langmuir. Moreover, study the effect of time according to it the adsorption process was fitted to Pseudo-second-order, and the effect of temperature that approved that the reaction was endothermic, spontaneous, and chemisorption process. The MOR-NH2 nanocomposite was tested and proven to effectively inhibit the growth of Escherichia coli ATCC® 25922™ and Staphylococcus aureus ATCC® 25923™ at low concentrations. To the best of our knowledge, this work is the first to report the usage of MOR-NH2 adsorbents for the removal of E122 dye in wastewater samples. The mechanism of interaction between MOR-NH2 and E122 dye was determining as it could be through Hydrogen bonding, pore filling, or through π-π interaction. This research offers a promising solution for purifying water sources that are contaminated with a variety of chemicals, microorganisms, and other contaminants.

Preparation of photoluminescent nanocomposite ink for detection and mapping of fingermarks.

Simple and efficient detection and mapping method based on a strong turn-on fluorescent pigment was developed for fingerprint analysis. We present a phosphor powder characterized by strong emission which is useful to achieve better fingerprint detection on multicolored or photoluminescent surfaces, such as currency notes characterized by optically changeable inks and highly fluorescent positions, because it offers better contrast and reduce the difficulty of background interference. Novel photochromic ink was prepared to establish a fingerprinted colorless film onto cellulose documents with green emission for anticounterfeiting applications as illustrated by photoluminescence spectra. Inorganic/organic nanoscale composite ink was prepared from rare-earth doped aluminate phosphor nanoparticles (PNPs; 27-49 nm) dispersed in a polyacrylic acid binding agent. PNPs were dispersed efficiently in polyacrylic acid to generate a colorless mark. The produced photochromic inks were spray-coated onto off-white paper sheets enclosing invisible fingermarks, and then exposed to thermofixation. Photochromic film was detected on paper surface presenting a transparent appearance under visible daylight and switchable to green under UV light. The CIE Lab parameters and photoluminescence spectra were studied under visible light and ultraviolet irradiation. The fingerprinted sheets showed fluorescence band at 517 nm upon excitation at 366 nm, showing a bathochromic shift and reversible photochromism without fatigue. The morphologies of pigment phosphor particles and fingerprinted sheets were inspected. The rheological properties of ink and mechanical behavior of the fingerprinted paper samples were explored. HIGHLIGHTS: Novel smart ink with alkaline-earth aluminate and polyacrylic acid was developed. Dual-mode fluorescent photochromism was presented for latent fingerprint analysis. Off-white fingerprinted films under daylight showed color change to green under UV. Fluorescence band monitored at 517 nm upon excitation at 366 nm. Fluorescent fingermark on paper sheets demonstrated good photostability.

Simple preparation of novel photochromic polyvinyl alcohol/carboxymethyl cellulose security barcode incorporated with lanthanide-doped aluminate for anticounterfeiting applications.

Forgery and low-quality products pose a danger to society. Therefore, there are increasing demands for the production of easy-to-recognize and difficult-to-copy anticounterfeiting materials. Products with smart photochromic and fluorescence properties can change colour and emission spectra responding to a light source. In this context, we devised a straightforward preparation of a luminescent polyvinyl alcohol/carboxymethyl cellulose (PVA/CMC) nanocomposite to function as a transparent labelling film. The lanthanide-doped aluminate (LdA) was prepared in the nanoparticle form to indicate diameters of 35-115 nm. Different ratios of the LdA were physically dispersed in the PVA/CMC nanocomposite label film to provide photochromic, ultraviolet protection, antimicrobial activity, and hydrophobic properties. Fluorescence peaks were detected at 365 and 519 nm to indicate a colour change to green. As a result of increasing the phosphor ratio, improved superhydrophobic activity was achieved as the contact angle was increased from 126.1° to 146.0° without affecting the film's original physical and mechanical properties. Both ultraviolet (UV) light protection and antibacterial activity were also investigated. The films showed a quick and reversible photochromic response without fatigue. The current strategy reported the development of a photochromic smart label that is transparent, cost effective, and flexible. As a result, numerous anticounterfeiting products can benefit from the current label for a better market. LdA-loaded PVA/CMC films demonstrated antibacterial activity between poor, good, very good, and outstanding as the percentage of LdA in the film matrix increased. The current film can be applied as a transparent photochromic security barcode for anticounterfeiting applications and smart packaging.

Development of silica-coated rare-earth doped strontium aluminate toward superhydrophobic, anti-corrosive and long-persistent photoluminescent epoxy coating.

Long-persistent phosphorescent smart paints have the ability to continue glowing in the dark for a prolonged time period to function as energy-saving products. Herein, new epoxy/silica nanocomposite paints were prepared with different concentrations of lanthanide-doped aluminate nanoparticles (LAN; SrAl2 O4 :Eu2+ ,Dy3+ ). The LAN pigment was firstly coated with silicon dioxide (SiO2 ) utilizing the heterogeneous precipitation technique to provide LAN-encapsulated between SiO2 nanoparticles (LAN@SiO2 ). The epoxy/silica/lanthanide-doped aluminate nanoparticles (ESLAN) nanocomposite paints were coated on steel. The prepared ESLAN paints were studied by transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray fluorescence (XRF) analysis, and energy-dispersive X-ray spectroscopy (EDS). The transparency and coloration properties of the nanocomposite coated films were explored by CIE Lab parameters and photoluminescence spectra. The ultraviolet-induced luminescence properties of the transparent coated films demonstrated greenish phosphorescence at 518 nm upon excitation at 368 nm. Both hardness and hydrophobic activities were investigated. The anticorrosion activity of the nanocomposite films coated onto mild steel substrates immersed in aqueous sodium chloride (NaCl(aq) ) (3.5%) was studied by electrochemical impedance spectroscopy (EIS). The silica-containing coatings were monitored to exhibit anticorrosion properties. Additionally, the nanocomposite films with LAN@SiO2 (25%) exhibited the optimized long-lasting luminescence properties in the dark for 90 min. The nanocomposite films showed highly reversible and durable long-lived phosphorescence.