Physicochemical Characterization Techniques Research Articles

Bifunctional Electrocatalysts for Overall and Hybrid Water Splitting.

Electrocatalytic water splitting driven by renewable electricity has been recognized as a promising approach for green hydrogen production. Different from conventional strategies in developing electrocatalysts for the two half-reactions of water splitting (e.g., the hydrogen and oxygen evolution reactions, HER and OER) separately, there has been a growing interest in designing and developing bifunctional electrocatalysts, which are able to catalyze both the HER and OER. In addition, considering the high overpotentials required for OER while limited value of the produced oxygen, there is another rapidly growing interest in exploring alternative oxidation reactions to replace OER for hybrid water splitting toward energy-efficient hydrogen generation. This Review begins with an introduction on the fundamental aspects of water splitting, followed by a thorough discussion on various physicochemical characterization techniques that are frequently employed in probing the active sites, with an emphasis on the reconstruction of bifunctional electrocatalysts during redox electrolysis. The design, synthesis, and performance of diverse bifunctional electrocatalysts based on noble metals, nonprecious metals, and metal-free nanocarbons, for overall water splitting in acidic and alkaline electrolytes, are thoroughly summarized and compared. Next, their application toward hybrid water splitting is also presented, wherein the alternative anodic reactions include sacrificing agents oxidation, pollutants oxidative degradation, and organics oxidative upgrading. Finally, a concise statement on the current challenges and future opportunities of bifunctional electrocatalysts for both overall and hybrid water splitting is presented in the hope of guiding future endeavors in the quest for energy-efficient and sustainable green hydrogen production.

Anticancer and Antibacterial Properties of Curcumin-Loaded Mannosylated Solid Lipid Nanoparticles for the Treatment of Lung Diseases.

Lung cancer and Mycobacterium avium complex infection are lung diseases associated with high incidence and mortality rates. Most conventional anticancer drugs and antibiotics have certain limitations, including high drug resistance rates and adverse effects. Herein, we aimed to synthesize mannose surface-modified solid lipid nanoparticles (SLNs) loaded with curcumin (Man-CUR SLN) for the effective treatment of lung disease. The synthesized Man-CUR SLNs were analyzed using various instrumental techniques for structural and physicochemical characterization. Loading curcumin into SLNs improved the encapsulation efficiency and drug release capacity, as demonstrated by high-performance liquid chromatography analysis. Furthermore, we characterized the anticancer effect of curcumin using the A549 lung cancer cell line. Cells treated with Man-CUR SLN exhibited an increased cellular uptake and cytotoxicity. Moreover, treatment with free CUR could more effectively reduce cancer migration than treatment with Man-CUR SLNs. Similarly, free curcumin elicited a stronger apoptosis-inducing effect than that of Man-CUR SLNs, as demonstrated by reverse transcription-quantitative PCR analysis. Finally, we examined the antibacterial effects of free curcumin and Man-CUR SLNs against Mycobacterium intracellulare (M.i.) and M.i.-infected macrophages, revealing that Man-CUR SLNs exerted the strongest antibacterial effect. Collectively, these findings indicate that mannose-receptor-targeted curcumin delivery using lipid nanoparticles could be effective in treating lung diseases. Accordingly, this drug delivery system can be used to target a variety of cancers and immune cells.

Postpolymerization Modification of Poly(2-vinyl-4,4-dimethyl azlactone) as a Versatile Strategy for Drug Conjugation and Stimuli-Responsive Release.

Postpolymerization modification of highly defined "scaffold" polymers is a promising approach for overcoming the existing limitations of controlled radical polymerization such as batch-to-batch inconsistencies, accessibility to different monomers, and compatibility with harsh synthesis conditions. Using multiple physicochemical characterization techniques, we demonstrate that poly(2-vinyl-4,4-dimethyl azlactone) (PVDMA) scaffolds can be efficiently modified with a coumarin derivative, doxorubicin, and camptothecin small molecule drugs. Subsequently, we show that coumarin-modified PVDMA has a high cellular biocompatibility and that coumarin derivatives are liberated from the polymer in the intracellular environment for cytosolic accumulation. In addition, we report the pharmacokinetics, biodistribution, and antitumor efficacy of a PVDMA-based polymer for the first time, demonstrating unique accumulation patterns based on the administration route (i.e., intravenous vs oral), efficient tumor uptake, and tumor growth inhibition in 4T1 orthotopic triple negative breast cancer (TNBC) xenografts. This work establishes the utility of PVDMA as a versatile chemical platform for producing polymer-drug conjugates with a tunable, stimuli-responsive delivery.

Ion exchange and Thermal Studies on n-butyl acetate zirconium(IV) phosphate: A Novel Hybrid Cation exchanger

n-butyl acetate zirconium (IV) phosphate has been reported as a novel hybrid ion exchanger, namely an organic-based hybrid ion exchanger. This newly reported material has been characterized by a number of physico-chemical characterization techniques including FTIR analysis, SEM study, UV-Vis spectrophotometry and elemental analysis. In addition to describing its method of synthesis, this research also reports on the characterization of its ion exchange properties such as its ion exchange capacity, concentration study, elution study and recycling study. Thermal behavior of the reported exchanger has also been explored at various temperatures revealing 91.4% of retention in ion exchange capacity on heating upto 2000C and 74.5% upto 4000C which exhibits the way to explore its applications in higher temperature ranges.

Wastewater sludge-derived hydrochar: Effect of operating conditions, activation, and potential use as adsorbent

Scientific management of wastewater sludge generated from biological wastewater treatment is necessary owing to its high moisture content and poor dewaterability. In this investigation, hydrothermal carbonization technique was implemented as a potential solution for wastewater sludge management. To further improve the surface properties of wastewater sludge-derived hydrochar (synthesized at 250 ℃ for 4 h of reaction time), three activation techniques, namely physical, alkali, and alkali followed by acid activation were implemented. The effect of three activation techniques on the properties of hydrochar was investigated using physico-chemical characterization techniques. The sludge-derived hydrochar activated with KOH (1:1 by weight) followed by HCl treatment (1 M) (HC-KA) showcased highly porous structured material having a surface area of 1119 m2 g–1, which was highest amongst the other activation methods chosen in this investigation. Thus, HC-KA was utilized as an adsorbent to evaluate the adsorptive removal of methylene blue (MB). The MB adsorption process followed Langmuir isotherm (R2 of 0.996) with a maximum adsorption capacity of 192.7 mg g–1 and pseudo-second-order reaction kinetics. The results demonstrated that wastewater sludge-derived activated hydrochar can be considered a promising material as an adsorbent in wastewater treatment.

Archaeometric study of Maya pottery from Comalcalco, Tabasco, Mexico

In this paper, structural, morphological, and mineralogical characterizations of Maya archaeological pottery from Comalcalco, Tabasco, Mexico are presented. The fired clay ceramic samples were taken from Maya settlements, previously classified in traditional way, using the type-variety method from physical and cultural features. It is shown that the ceramics studied have some similarities and differences, indicating that the classification by type-variety must be complemented with physicochemical characterization techniques to issue more compelling proposals about Maya ceramics. Physicochemical analysis revealed that the raw materials used by ceramic groups to manufacture different types of pottery such as vases, cups, incense burners and pots have the same composition and origin than the raw materials located in the surrounded region of the archaeological site. Quite similar mineralogical compositions were found between the various studied ceramic materials which indicate a great knowledge of the manufactured materials type. However, significant differences in fired temperatures and carbon concentration were observed which may be related to type of materials used as fuel (organic materials) and whether such ceramics were fired in open or pit ovens.

A template-assisted method for synthesizing TiO2 nanoparticles and Ni/TiO2 nanocomposites for urea electrooxidation

The exploration of electrocatalytic urea-assisted wastewater treatment as a method for sustainable energy generation presents a compelling approach within the domain of green chemistry. In this context, titanium dioxide (TiO2) and nickel-doped TiO2 (Ni@TiO2) nanocomposites were developed through an innovative organic template-assisted synthesis strategy. These were denoted as m-TiO2-org and Ni@m-TiO2-org, respectively, to create cost-effective and high-performance electrodes for urea electrooxidation in urea-based fuel cells. The structural and chemical properties of the fabricated m-TiO2-org and Ni@m-TiO2-org materials were meticulously analyzed using a suite of physicochemical characterization techniques, including Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Thermogravimetric Analysis (TGA), and Energy-Dispersive X-ray Spectroscopy (EDX). These investigations revealed that both m-TiO2-org and Ni@m-TiO2-org materials predominantly consisted of irregular monolithic microparticles formed through the aggregation of spherical nanoparticles, with diameters ranging from 8.16 nm to 13.1 nm. Subsequent evaluations of these TiO2-based materials as electrocatalysts for urea electrooxidation demonstrated their efficacy, as evidenced by voltammetric and electrochemical impedance spectroscopy measurements. Notably, the Ni@m-TiO2-org variant exhibited enhanced electrochemical performance, attributed to the presence of Ni2+ sites. These sites facilitated electrochemical activation and the formation of active NiOOH sites, leading to a significant increase in the current density (0.78 mA/cm2 at 1.523 V vs. the Reversible Hydrogen Electrode (RHE)), as a fiftyfold enhancement compared to m-TiO2-org@Glassy Carbon Electrode (GCE) under similar conditions (3 M KOH containing 3 M urea), with a Tafel slope of 33 mV/decade. This research not only elucidates the potential of TiO2-based nanocomposites in the electrooxidation of urea but also heralds the development of innovative electrode materials for commercial electrochemical cells, marking a significant advancement in the field of electrocatalysis and sustainable energy technology.

Flotation recovery of monazite from kaolinite using sodium oleate collector: Understanding mineral–collector interaction

Recently, the flotation of major rare earth elements (REE) minerals including bastnasite, monazite, and xenotime has been attracting high level of attention. However, there are numerous challenges associated with achieving selective recovery of REE minerals from different gangue minerals. Paramount among the challenges is the abundance of fine clay and silicate gangue minerals in complex low grade REE bearing ores. These gangue minerals are usually recovered along with REE minerals, which can result in concentrate grade dilution. In this study, laboratory microflotation tests, coupled with physicochemical characterization techniques including zeta potential and X-ray photoelectron spectroscopy (XPS) analyses were conducted on monazite and kaolinite using sodium oleate as a collector. Microflotation experiments established that the floatability of monazite is high at pH 5–9, where kaolinite had lower flotation response. Complementary zeta potential and XPS measurements revealed that at pH 9, sodium oleate adsorbs onto monazite surfaces via hydroxylated REE ions and the adsorbed oleate contributes oxygen atoms to the metaphosphate components on monazite surfaces, leading to the chemical bonding between oleate and monazite surfaces, whiles there was marginal/negligible interaction between oleate and kaolinite. The findings from this study demonstrate distinct differences in the flotation characteristics of monazite and kaolinite. The selective adsorption of oleate ions onto monazite surface was responsible for the distinct flotation response identified at alkaline pulp pH conditions. The learnings from this work indicate that kaolinite is not likely to be recovered via true flotation, at the conditions applied in this study, thus monazite can be separated from kaolinite when using sodium oleate as a collector.

Free radical graft polymerization of hydroxyethyl methacrylate and acrylic acid on polyetherimide membrane surface via redox system to improve anti-fouling and oil resistance performance

In this paper, a new scheme of graft polymerization of acrylic acid (AA) and hydroxyethyl methacrylate (HEMA) initiated by the generation of free radicals in a redox system was used to modify the surface of polyetherimide (PEI) membranes and to improve the antifouling and oil resistance properties. Various physicochemical characterization techniques (ATR-FTIR, XPS, TG, SEM, AFM, etc.) confirmed the successful grafting of hydrophilic monomers onto the PEI membrane surface. Further, the effects of different monomer concentrations on graft density, permeation separation, contamination resistance, and mechanical properties were investigated. Both PEI-g-PAA and PEI-g-PHEMA showed better hydrophilicity (WCA decreased from 60° in PEI to 33° and 45°, respectively), efficient separation (75–84%) in oil-containing wastewater filtration tests with methyl tert-butyl ether (MTBE) and petroleum ether with a slight decrease in mechanical strength. In addition, bovine serum albumin (BSA) and MTBE were selected as contaminants to examine the antifouling properties. Compared to the flux recovery rate (FRR) of 75% for the original PEI membranes, the grafted membranes almost wholly recovered the permeate flux with a simple backwash of ultrapure water. In summary, the results of the above study suggest the development of a novel and simple preparation strategy for surface grafting modification of PEI membranes, which will facilitate the subsequent research of PEI materials in membrane development, and the resulting grafted membranes will be of developmental and exploratory value in the field of oil and water treatment.

Multidrug-resistant Bacillus species isolated from hospital soil environment is controlled by nanobiotics incorporated nanoformulation

Multidrug resistance is a serious hazard to the environment, it claims a large number of lives every year. Lack of drug options and easy transmission of these organisms remain the biggest threat in treating the relative infections whose causative systems have evolved and become stronger in due course of time. Hospitals serve as one of the largest breeding grounds for harbouring these organisms. This study aims to isolate and characterize multidrug-resistant microorganisms from soil samples collected from hospital waste dumping premises. Polyherbal nanoformulation was synthesized from ethno-medicinal source Triphala (three berries) and characterized using various physico-chemical characterization techniques. The antibacterial efficacy of the polyherbal nanoformulation was evaluated by employing various assays to determine MIC, MBC, and biofilm inhibition potential in isolated strains. Bacterial colonies were isolated and the DNA was sequenced. The isolated organisms were identified as Bacillus cereus, Bacillus licheniformis, and Bacillus pumilus and they were subjected to antibiotic susceptibility by using various antibiotics. It was found that all the microorganisms were multidrug-resistant and possessed resistance to various classes of antibiotics. The various antibacterial assays showed that the polyherbal nanoformulation was highly effective in controlling growth and biofilm formation even at lower concentrations when compared with commercial antibiotics. The novelty of this research work lies in combining the beneficial effects of silver and polyherbal drugs into a single Polyherbal nanoformulation. This is the first novel report to utilize polyherbal nanoformulation to control the multidrug-resistant microorganisms thriving in hospital waste dumping sites. Hence, this nanobiotics incorporated polyherbal nanoformulation can be developed into a commercial product to treat the hospital waste material before dumping it into the environment.

Bolivian natural zeolite as a low-cost adsorbent for the adsorption of cadmium: Isotherms and kinetics

Population growth in recent years has led to increased wastewater production and pollution of water resources. This situation also heavily affects Bolivia, so wastewater treatment methods and materials suitable for Bolivian society should be explored. This study investigated the natural Bolivian Zeolite (BZ) and its NaCl-modified structure (NaBZ) as adsorbents for cadmium removal from water. The natural BZ and the modified form NaBZ were investigated by different physicochemical characterization techniques. Furthermore, XPS and FT-IR techniques were used to investigate the adsorption mechanisms. The cadmium adsorption on BZ and NaBZ was analyzed using various mathematical models, and the Langmuir model provided a better description of the experimental adsorption data with cadmium adsorption capacities of 20.2 and 25.6 mg/g for BZ and NaBZ, respectively. The adsorption followed the pseudo-second order kinetics. The effect of different parameters, such as initial cadmium concentration and pH on the adsorption was studied. In addition, the results of the regeneration test indicated that both BZ and NaBZ can be regenerated by using hydrochloric acid (HCl). Finally, the adsorption experiment of BZ and NaBZ on a real water sample (brine from Salar de Uyuni salt flat) containing a mixture of different heavy metals was carried out. The results obtained in this study demonstrate the effectiveness of natural BZ and modified NaBZ in the removal of heavy metals from wastewater.

Unveiling the impact of enhanced hydrophobicity of ZIF-71 on butanol purification: insights from experimental and molecular simulations.

Biofuels offer significant potential for reducing carbon emissions and enhancing energy sustainability, but their efficient purification remains a significant challenge. In this study, the performance of a hydrophobic zeolitic imidazolate framework, ZIF-71(ClBr)-SE, in the adsorptive separation of butanol from single- and ternary-component systems (acetone, butanol, and ethanol) was investigated and compared with ZIF-8 and ZIF-71. Physicochemical characterization techniques, including XRD, SEM, BET, TGA, and DVS, confirmed that the modified ZIF-71 is hydrophobic, isostructural with ZIF-71, and has a higher surface area. Adsorption tests in aqueous solutions revealed that ZIF-71(ClBr)-SE unexpectedly showed a higher affinity for acetone over butanol. DFT molecular simulations provided insights into solute-ZIF interactions, highlighting preferential sites for ZIF interaction.

Catalytic system having an organotellurium ligand on graphene oxide: immobilization of Pd(0) nanoparticles and application in heterogeneous catalysis of cross-coupling reactions.

First heterogeneous catalytic system, having a covalently linked hybrid bidentate organotellurium ligand [i.e., PhTe-CH2-CH2-NH2] on the surface of graphene oxide, has been synthesized with immobilized and stabilized Pd(0) nanoparticles. To the best of our knowledge, it is the first such catalytic system in which a heterogenized organotellurium ligand has been used. It has been well-characterized using different physicochemical characterization techniques viz. P-XRD, XPS, HR-TEM, EELS, FE-SEM, EDX, TGA, BET surface area analysis, FT-IR spectroscopy, and Raman spectroscopy. The Pd content of the final system has been quantified using ICP-OES. Its applications have been explored in Suzuki-Miyaura C-C cross coupling and C-O cross coupling reactions. Hot filtration experiments corroborate the heterogeneous nature of the catalysis. It is recyclable for up to five reaction cycles in Suzuki-Miyaura and C-O cross coupling with marginal loss in performance. It also catalyzes the reactions of chloroarenes such as chlorobenzene, 4-chloroaniline, 1-chloro-4-nitrobenzene, 4-chloroacetophenone, 4-chlorobenzophenone for Suzuki coupling, and 1-chloro-4-nitrobenzene, 4-chlorobenzonitrile, chlorobenzene, and 4-chlorotoluene for C-O coupling. P-XRD, FE-SEM, and EDX study reveals that the catalytic system retains its structural originality and functionality after recycling.

Removal of cadmium from aqueous solution by magnetic biochar: adsorption characteristics and mechanism.

Experiments were conducted to investigate the potential of the efficient resource utilization of waste cow manure and corn straw in an agricultural ecosystem. In this study, a magnetic cow manure and straw biochar were synthesized by a co-precipitation method, and cadmium (Cd(II)) was removed by adsorption in aqueous solution. Several physicochemical characterization techniques were applied, including SEM, BET, Zeta, FTIR, Raman, XPS, and VSM. The effects of pH value, magnetic biochar content, adsorption kinetics, and isothermal adsorption on the adsorption of Cd(II) were investigated. The physicochemical characterizations revealed that the physical and chemical properties of the magnetic biochar were substantially changed compared to the unmodified biochar. The results showed that the surface of the biochar became rough, the number of oxygen (O)-containing functional groups increased, and the specific surface area increased. The results of the adsorption experiments showed that the adsorption capacity was affected by pH, magnetic biochar addition, Cd(II) concentration, and adsorption time. The adsorption kinetics and isothermal adsorption experiments showed that the Cd(II) adsorption processes of the cow manure and corn straw magnetic biochars were consistent with the Freundlich model and pseudo-second-order kinetic model. The results also showed that the Cd(II) adsorption effect of cow manure magnetic biochar was found to be more effective than that of corn straw magnetic biochar. The optimal conditions for Cd(II) adsorption were 800 ℃ for cow manure magnetic biochar, with a pH value of 5 and 0.14g biochar addition, and 600 ℃ for straw magnetic biochar with a pH value of 8 and 0.12g biochar addition. In conclusion, the cow manure magnetic biochar was an effective adsorbent for the absorption of Cd(II) in wastewater.

Aging-Sensitive Fast-Charging for Heavy-Duty Electric Vehicles

To use lithium-ion cells on-board electric vehicles (EVs) safely and efficiently, a battery management system (BMS) is essential. It monitors the battery’s states and controls utilization by limiting e.g., current and temperature. Advanced BMS increasingly use electrochemical models to assess internal states of battery cells and apply usage constraints based on these [1]. The performance of an electrochemical BMS is closely tied to the performance of the underlying model and the accuracy of its parameters [2]. We employ a novel re-parametrization method to update electrochemically constrained optimal fast-charging procedure to minimize battery degradation. The parameters of electrochemical models are typically identified through a combination of physico-chemical characterization techniques and curve fitting [3]. Since model parameters change with aging [4], there is a need to re-parametrize electrochemical models on-board to conserve model accuracy. As basis for this re-parametrization, we propose a novel reference performance test that can be incorporated into a conventional over-night charge and performed intermittently.Optimal control has previously been demonstrated for fast-charging in EV applications [1]. However, electrochemical, and mechanical degradation need to be considered to allow optimal fast charging throughout batteries’ lifetimes. Khalik et al. [5] demonstrated how a charging procedure could be designed a-priori for the entire cycle life, considering a direct implementation of the solid-electrolyte-interphase growth and capacity fade due to the associated lithium consumption. Such approaches can extend battery lifetime, but neither yield optimal charging-procedures at every state-of-health nor handle unknown aging modes on the fly. Our proposed approach involves intermittent identification of electrochemical model parameters and subsequent update of the fast-charging protocol such that it adheres to electrochemical constraints throughout the entire battery lifetime.In this work, summarized in Figure 1, we present this methodology and show results from an experimental study testing the proposed approach vs. conventional charging procedures. The experimental study is performed on state-of-the art automotive cells used in heavy-duty electric vehicles.Figure caption: Comparison of a conventional electrochemically constrained fast-charging procedure with the aging-sensitive approach proposed in the present work.

Anionic Hyperbranched Amphiphilic Polyelectrolytes as Nanocarriers for Antimicrobial Proteins and Peptides.

This manuscript presents the synthesis of hyperbranched amphiphilic poly (lauryl methacrylate-co-tert-butyl methacrylate-co-methacrylic acid), H-P(LMA-co-tBMA-co-MAA) copolymers via reversible addition fragmentation chain transfer (RAFT) copolymerization of tBMA and LMA, and their post-polymerization modification to anionic amphiphilic polyelectrolytes. The focus is on investigating whether the combination of the hydrophobic characters of LMA and tBMA segments, as well as the polyelectrolyte and hydrophilic properties of MAA segments, both distributed within a unique hyperbranched polymer chain topology, would result in intriguing, branched copolymers with the potential to be applied in nanomedicine. Therefore, we studied the self-assembly behavior of these copolymers in aqueous media, as well as their ability to form complexes with cationic proteins, namely lysozyme (LYZ) and polymyxin (PMX). Various physicochemical characterization techniques, including size exclusion chromatography (SEC) and proton nuclear magnetic resonance (1H-NMR), verified the molecular characteristics of these well-defined copolymers, whereas light scattering and fluorescence spectroscopy techniques revealed promising nanoparticle (NP) self- and co-assembly properties of the copolymers in aqueous media.

Recyclable waste derived green triboelectric nanogenerator for Self-Powered synthesis of Defect-Free graphene via Mechano-Electrochemical exfoliation

With an upsurge in global waste generation per capita, and energy consumption, there is a simultaneous need for new strategies that can reuse plastic waste and harvest energy for practical applications. Hence, we propose a green triboelectric nanogenerator derived from waste (W-TENG), which was used to demonstrate a novel self-powered application of mechano-electrochemical exfoliation process for graphene synthesis. The W-TENG comprised of discarded plastic banner as tribo-negative material and chocolate wrapper as tribo-positive material, which were confirmed to be polyvinyl chloride (PVC) and aluminium, respectively by using different characterization techniques. The as-fabricated W-TENG exhibited an output VOC of 35 V and ISC of 0.4 µA. The instantaneous power output of the W-TENG was calculated as 0.0217 W/m2 at 45 MΩ external resistance load. The force-dependency behaviour of W-TENG demonstrated that the voltage and current output increased from 20 V to 58 V, and 0.2 to 0.4 µA, upon changing the applied force from 9 N to 30 N. Further, we have demonstrated a novel application, wherein 2D graphene nanosheets were synthesized via mechano-electrochemical exfoliation under highly conductive acidic solution, powered by the W-TENG. Various physico-chemical characterization techniques confirmed it to be defect free few-layered graphene. This work demonstrates a promising “waste to wealth” strategy of using discarded plastic waste to develop a robust mechanical energy harvester to power various applications.

Solution combustion synthesis of metal tungstates for chromium reduction and dye degradation for environmental remediation

Metal tungstates CuWO4 and ZnWO4 nanoparticles were synthesized by simple, efficient, low temperature solution combustion synthesis using metal nitrate and ammonium tungstate. The prepared samples were characterized by different physicochemical characterization techniques i. e.XRD, FTIR, SEM, EDAX, UV–vis DRS, PL and XPS techniques. The petal and flower like morphology of these samples were obtained by using SEM analysis. Based on this novelty, we have studied the photodegradation of methylene blue and rhodamine B dyes in visible light. Results of photocatalytic dye degradation reaction reveal that both the tungstate’s can be employed as photocatalyst under visible light irradiation. ZnWO4 nanoparticles show comparatively higher activity than that of CuWO4, it may due to structural property as well as completely filled d10 orbital of Zn. Both CuWO4 as well as ZnWO4 were also applied to reduce toxic Cr(VI) into harmless Cr(III). This work implemented for the betterment of environmental remediation to the society.

β-Cyclodextrin capped ZnS nanoparticles for CER-assisted colorimetric and spectrophotometric detection of Pb2⁺, Cu2⁺, and Hg2⁺ in an aqueous solution

Herein, simple, low-cost, and room-temperature synthesis of beta-cyclodextrin (β-CD) stabilized zinc sulfide nanoparticle (ZnS NP) through the chemical precipitation method has been reported for cation exchange reaction (CER) based colorimetric sensing of Pb2+, Cu2+, and Hg2+. Formation of β-CD stabilized ZnS NPs (ZnS@β-CD) was verified by physicochemical characterization techniques such as XRD, XPS, FE-SEM, and TEM. ZnS@β-CD NPs showed color change selectively for the metal ions Pb2⁺, Cu2⁺, and Hg2⁺ among the various metal ions including Sn2⁺, Cr³⁺, Mn2⁺, Fe³⁺, Co2⁺, Ni2⁺, and Cd2⁺. The solubility product of reactants and the transformed products are the reason for selective CER of ZnS@β-CD NPs towards Pb2⁺, Cu2⁺, and Hg2⁺ ions. ZnS@β-CD NPs dispersion revealed rapid color change from white to orange, black, and bright yellow on the addition of higher concentrations of Pb2⁺, Cu2⁺, and Hg2⁺ respectively. This color change is due to the formation of complete CER-transformed nanostructures such as PbS, CuS, and HgS in higher concentrations (10⁻1- 10⁻³ M) of corresponding metal ions. The partial CER altered products Zn1−x,PbxS, Zn1−xCuxS and Zn1−xHgxS were detected due to the appearance of pale color in the lower metal ions concentrations of 10⁻⁴ - 10⁻⁶ M. This CER assisted transformation was also monitored through spectrophotometric methods. Moreover, infrared spectroscopic analysis was used to testify the structure of CER transformed product. The synthesized ZnS@β-CD NPs act as an efficient CER-based sensor for distinguishing and determining Pb2⁺, Cu2⁺, and Hg2⁺ at different level concentrations in the aqueous solution.

Comparative analysis of extraction methods, proximate composition, and physicochemical and functional properties of fruit seed proteins: A comprehensive review

AbstractThis comprehensive review delves into the realm of fruit seed proteins, examining their extraction methods, physicochemical properties, and functional characteristics. These proteins exhibit tremendous potential for diverse applications within the food industry. By gaining insights into efficient extraction techniques and understanding the physicochemical and functional properties of fruit seed proteins, researchers and industry professionals can harness their advantages to develop innovative food products. Various extraction methods, such as acid alkali, microwave‐assisted, ultrasound‐assisted, reverse micelle extraction, and the Box–Behnken experimental design, have been used for extracting proteins from a range of fruit seeds, including jackfruit, kiwi, watermelon, date palm, and grape seeds. The selection of these methods was based on their efficiency, protein yield, and compatibility with fruit seed proteins, with any associated limitations duly acknowledged by the researchers. The review also explores physicochemical characterization techniques such as Fourier transform infrared, thermogravimetric analysis, differential scanning calorimetry, and scanning electron microscopy, used specifically for jackfruit seed protein, while delving into essential functional properties including solubility, water‐binding capacity, oil‐binding capacity, emulsifying capacity, foaming capacity, and bulk density. These properties play a crucial role in determining the suitability of fruit seed proteins for various food applications, significantly impacting factors like texture, crispiness, and color. Waste fruit seeds, often overlooked, can serve as a valuable source of proteins, possessing multifunctional properties encompassing nutrition, structure, enzymes, emulsification, foaming, gelation, and thickening. However, compared to other protein sources, fruit seed proteins have received limited scientific attention, rendering this review a distinctive and valuable contribution to the existing literature by offering comprehensive insights into extraction methods and properties.