This work reports the successful preparation of nanoporous iron oxide/carbon composites through the in-situ growth of Prussian blue (PB) nanoparticles on the surface of graphene oxide (GO) nanosheets. The applied thermal treatment allows the conversion of PB nanoparticles into iron oxide (Fe2O3) nanoparticles. The resulting iron oxide/carbon composite exhibits higher specific capacitance at all scan rates than pure GO and Fe2O3 electrodes due to the synergistic contribution of electric double-layer capacitance from GO and pseudocapacitance from Fe2O3. Notably, even at a high current density of 20 A g-1, the iron oxide/carbon composite still shows a high capacitance retention of 51%, indicating that the hybrid structure provides a highly accessible path for diffusion of electrolyte ions.

There is enormous interest in combining two or more nanoparticles for various biomedical applications, especially in anti-cancer agent delivery. In this study, the microsphere nanoparticles were prepared (MSNPs) and their impact on cancer cells was examined. The MSNPs were prepared by using the hydrothermal method where strontium (Sr), barium (Ba), dysprosium (Dy), samarium (Sm), and iron oxide (Fe8-2xO19) were combined, and dysprosium (Dy) and samarium (Sm) was substituted with strontium (Sr) and barium (Ba), preparing Sr0.5Ba0.5DyxSmxFe8-2xO19 (0.00 ≤ x ≤ 1.0) MSNPs. The microspheres were characterized by X-ray powder diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX) techniques. The diffraction pattern of nanohexaferrites (NHFs) reflected the signature peaks of the hexagonal structure. The XRD revealed a pure hexagonal structure without any undesired phase, which indicated the homogeneity of the products. The crystal size of the nanoparticles were in the range of 22 to 36 nm by Scherrer's equation. The SEM of MSNPs showed a semi-spherical shape with a high degree of aggregation. TEM and HR-TEM images of MSNPs verified the spherical shape morphology and structure that approved an M-type hexaferrite formation. The anti-cancer activity was examined on HCT-116 (human colorectal carcinoma) and HeLa (cervical cancer cells) using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and post-48 h treatment of MSNPs caused a dose-dependent inhibition of HCT-116 and HeLa cell proliferation and growth. Conversely, no significant cytotoxic effect was observed on HEK-293 cells. The treatments of MSNPs also induced cancer cells DNA disintegration, as revealed by 4',6-diamidino-2-phenylindole (DAPI) staining. Finally, these findings suggest that synthesized MSNPs possess potential inhibitory actions on cancerous cells without harming normal cells.

The reuse and separation of nanomaterials from an aquatic solution is always challenging and may cause nanotoxicity if not separated completely. Nanomaterial immobilization on the surface of a macro-size material could be an effective approach to developing an efficient composite for groundwater purification. Herein, polyaniline and graphene oxide nanosheet immobilized granular tea waste (PANI/GO@GTW) has been synthesized to remove the anionic and cationic contaminants from groundwater. The synthesized materials were characterized by SEM, XRD, XPS, and FTIR spectroscopies. The optimization of experimental conditions was tested for bromide (Br−) removal from synthetic water. The results revealed that Br− adsorption behavior onto the synthesized materials was as follows: PANI/GO < PANI/GTW < PANI < PANI/GO@GTW. The optimum removal of Br− ions was observed at pH 3 with 90 min of saturation time. Br− adsorption onto PANI/GO@GTW followed the pseudo-first-order kinetic and Langmuir isotherm model, and electrostatic interaction was involved in the adsorption process. The optimum adsorption of Br− onto PANI/GO@GTW was found to be 26.80 m/g. The application of PANI/GO@GTW on real groundwater treatment demonstrated the effective removal of anion pollutants such as F−, Cl−, Br−, NO3−, and PO43−. This study revealed that PANI/GO@GTW successfully reduced Br− concentrations in synthetic and real groundwater and can be used for large-scale applications.

An evaluation of the ameliorative effect of pomegranate peel extract (PPE) in counteracting the toxicity of iron oxide nanoparticles (Fe2O3-NPs) that cause hepatic tissue damage is focused on herein. Forty male albino mice were haphazardly grouped into four groups as follows: the first control group was orally gavage daily with physiological saline; the second group received 100 mg/kg of PPE by the oral route day after day; the third group received 30 mg/kg Fe2O3-NPs orally; and the fourth group received both PPE and Fe2O3-NPs by the oral route, the same as the second and third sets. Later, after the completion of the experiment, we collected the liver, blood, and bone marrow of bone specimens that were obtained for further laboratory tests. For instance, exposure to Fe2O3-NPs significantly altered serum antioxidant biomarkers by decreasing the levels of total antioxidant capacity (TAC), catalase (CAT), and glutathione s-transferase (GST). Additionally, it caused changes in the morphology of hepatocytes, hepatic sinusoids, and inflammatory Kupffer cells. Furthermore, they significantly elevated the number of chromosomal aberrations including gaps, breaks, deletions, fragments, polyploidies, and ring chromosomes. Moreover, they caused a significant overexpression of TIMP-1, TNF-α, and BAX mRNA levels. Finally, the use of PPE alleviates the toxicity of Fe2O3-NPs that were induced in the hepatic tissues of mice. It is concluded that PPE extract has mitigative roles against the damage induced by Fe2O3-NPs, as it serves as an antioxidant and hepatoprotective agent. The use of PPE as a modulator of Fe2O3-NPs' hepatotoxicity could be considered as a pioneering method in the use of phytochemicals against the toxicity of nanoparticles.

Zeolitic imidazolate frameworks (ZIFs) are increasingly gaining attention in many application fields due to their outstanding porosity and thermal stability, among other exceptional characteristics. However, in the domain of water purification via adsorption, scientists have mainly focused on ZIF-8 and, to a lesser extent, ZIF-67. The performance of other ZIFs as water decontaminants is yet to be explored. Hence, this study applied ZIF-60 for the removal of lead from aqueous solutions; this is the first time ZIF-60 has been used in any water treatment adsorption study. The synthesized ZIF-60 was subjected to characterization using FTIR, XRD and TGA. A multivariate approach was used to investigate the effect of adsorption parameters on lead removal and the findings revealed that ZIF-60 dose and lead concentration are the most significant factors affecting the response (i.e., lead removal efficiency). Further, response surface methodology-based regression models were generated. To further explore the adsorption performance of ZIF-60 in removing lead from contaminated water samples, adsorption kinetics, isotherm and thermodynamic investigations were conducted. The findings revealed that the obtained data were well-fitted by the Avrami and pseudo-first-order kinetic models, suggesting that the process is complex. The maximum adsorption capacity (qmax) was predicted to be 1905 mg/g. Thermodynamic studies revealed an endothermic and spontaneous adsorption process. Finally, the experimental data were aggregated and used for machine learning predictions using several algorithms. The model generated by the random forest algorithm proved to be the most effective on the basis of its significant correlation coefficient and minimal root mean square error (RMSE).

Protein kinases are key regulators of cell function, the abnormal activity of which may induce several human diseases, including cancers. Therefore, it is of great significance to develop a sensitive and reliable method for assaying protein kinase activities in real biological samples. Here, we report the phosphorylation-dependent surface-enhanced Raman scattering (SERS) readout of spermine-functionalized silver nanoparticles (AgNPs) for protein kinase A (PKA) activity assay in cell extracts. In this assay, the presence of PKA would phosphorylate and alter the net charge states of Raman dye-labeled substrate peptides, and the resulting anionic products could absorb onto the AgNPs with cationic surface charge through electrostatic attraction. Meanwhile, the Raman signals of dyes labeled on peptides were strongly enhanced by the aggregated AgNPs with interparticle hot spots formed in assay buffer. The SERS readout was directly proportional to the PKA activity in a wide range of 0.0001-0.5 U·μL-1 with a detection limit as low as 0.00003 U·μL-1. Moreover, the proposed SERS-based assay for the PKA activity was successfully applied to monitoring the activity and inhibition of PKA in real biological samples, particularly in cell extracts, which would be beneficial for kinase-related disease diagnostics and inhibitor screening.

Herein, a chitosan (CH) and fluroapatite (TNP) based CH-TNP composite was synthesized by utilizing seafood waste and phosphate rock and was tested for divalent copper (Cu(II)) adsorptive removal from water. The XRD and FT-IR data affirmed the formation of a CH-TNP composite, while BET analysis showed that the surface area of the CH-TNP composite (35.5 m2/g) was twice that of CH (16.7 m2/g). Mechanistically, electrostatic, van der Waals, and co-ordinate interactions were primarily responsible for the binding of Cu(II) with the CH-TNP composite. The maximum Cu(II) uptake of both CH and CH-TNP composite was recorded in the pH range 3-4. Monolayer Cu(II) coverage over both CH and CH-TNP surfaces was confirmed by the fitting of adsorption data to a Langmuir isotherm model. The chemical nature of the adsorption process was confirmed by the fitting of a pseudo-second-order kinetic model to adsorption data. About 82% of Cu(II) from saturated CH-TNP was recovered by 0.5 M NaOH. A significant drop in Cu(II) uptake was observed after four consecutive regeneration cycles. The co-existing ions (in binary and ternary systems) significantly reduced the Cu(II) removal efficacy of CH-TNP.

The rapidly growing global problem of infectious pathogens acquiring resistance to conventional antibiotics is an instigating reason for researchers to continue the search for functional as well as broad-spectrum antimicrobials. Hence, we aimed in this study to synthesis silver-copper oxide (Ag-CuO) nanohybrids as a function of Ag concentration (0.05, 0.1, 0.3 and 0.5 g) via the one-step hydrothermal method. The bimetallic Ag-CuO nanohybrids Ag-C-1, Ag-C-2, Ag-C-3 and Ag-C-4 were characterized for their physico-chemical properties. The SEM results showed pleomorphic Ag-CuO crystals; however, the majority of the particles were found in spherical shape. TEM results showed that the Ag-CuO nanohybrids in formulations Ag-C-1 and Ag-C-3 were in the size range of 20-35 nm. Strong signals of Ag, Cu and O in the EDX spectra revealed that the as-synthesized nanostructures are bimetallic Ag-CuO nanohybrids. The obtained Ag-C-1, Ag-C-2, Ag-C-3 and Ag-C-4 nanohybrids have shown their MICs and MBCs against E. coli and C. albicans in the range of 4-12 mg/mL and 2-24 mg/mL, respectively. Furthermore, dose-dependent toxicity and apoptosis process stimulation in the cultured human colon cancer HCT-116 cells have proven the Ag-CuO nanohybrids as promising antiproliferative agents against mammalian cancer.

In this study, zinc oxide nanoparticles (ZnO) and nanohydroxyapatite (NHAP) were prepared in the presence of date palm pits extract (DPPE) and eggshells, respectively. Another four nanocomposites were prepared from ZnO and NHAP in different ratios (ZP13, ZP14, ZP15, and ZP16). DPPE and all nanomaterials were characterized using GC-MS, zeta potentials, particle size distributions, XRD, TEM, EDX, FTIR, and pHPZC. The characterization techniques confirmed the good distribution of ZnO nanoparticles on the surface of NHAP in the prepared composites. Particles were found to be in the size range of 42.3-66.1 nm. The DPPE analysis confirmed the presence of various natural chemical compounds which act as capping agents for nanoparticles. All the prepared samples were applied in the adsorption and photocatalytic degradation of methylene blue under different conditions. ZP14 exhibited the maximum adsorption capacity (596.1 mg/g) at pH 8, with 1.8 g/L as the adsorbent dosage, after 24 h of shaking time, and the static adsorption kinetic process followed a PSO kinetic model. The photocatalytic activity of ZP14 reached 91% after 100 min of illumination at a lower MB concentration (20 mg/L), at pH 8, using 1.5 g/L as the photocatalyst dosage, at 25 °C. The photocatalytic degradation of MB obeyed the Langmuir-Hinshelwood first-order kinetic model, and the photocatalyst reusability exhibited a slight loss in activity (~4%) after five cycles of application.

To meet the growing demand for efficient and sustainable power sources, it is crucial to develop high-performance energy storage systems. Additionally, they should be cost-effective and able to operate without any detrimental environmental side effects. In this study, rice husk-activated carbon (RHAC), which is known for its abundance, low cost, and excellent electrochemical performance, was combined with MnFe2O4 nanostructures to improve the overall capacitance of asymmetric supercapacitors (ASCs) and their energy density. A series of activation and carbonization steps are involved in the fabrication process for RHAC from rice husk. Furthermore, the BET surface area for RHAC was determined to be 980 m2 g-1 and superior porosities (average pore diameter of 7.2 nm) provide abundant active sites for charge storage. Additionally, MnFe2O4 nanostructures were effective pseudocapacitive electrode materials due to their combined Faradic and non-Faradic capacitances. In order to assess the electrochemical performance of ASCs extensively, several characterization techniques were employed, including galvanostatic charge -discharge, cyclic voltammetry, and electrochemical impedance spectroscopy. Comparatively, the ASC demonstrated a maximum specific capacitance of ~420 F/g at a current density of 0.5 A/g. The as-fabricated ASC possesses remarkable electrochemical characteristics, including high specific capacitance, superior rate capability, and long-term cycle stability. The developed asymmetric configuration retained 98% of its capacitance even after 12,000 cycles performed at a current density of 6A/g, demonstrating its stability and reliability for supercapacitors. The present study demonstrates the potential of synergistic combinations of RHAC and MnFe2O4 nanostructures in improving supercapacitor performance, as well as providing a sustainable method of using agricultural waste for energy storage.

In this study, we report on the fabrication and utilization of NiCr alloy nanoparticles (NPs)-decorated carbon nanofibers (CNFs) as efficient and competent non-precious catalysts for the hydrolytic dehydrogenation of ammonia borane (AB) at 25 ± 2 °C. The introduced NFs have been fabricated in one step using a high-temperature thermal decomposition of the prepared electrospun nanofiber mats (nickel acetate tetrahydrate, chromium acetate dimer, and polyvinyl alcohol) in an inert atmosphere. The chemical composition of the NFs with different proportions of Ni1-xCrx (x = 0.0, 0.1, 0.15, 0.2, 0.25, 0.3) was established via standard characterization techniques. These techniques proved the formation of disorder Cr2Ni3 alloy and carbon for all the formulations. The as-synthesized composite NFs exhibited a higher catalytic performance for AB dehydrogenation than that of Cr-free Ni-CNFs. Among all the formulations, the sample composed of 15% Cr shows the best catalytic performance, as more H2 was released in less time. Furthermore, it shows good stability, as it is recyclable with little decline in the catalytic activity after six cycles. It also demonstrates the activation energy, entropy (ΔS), and enthalpy (ΔH) with 37.6 kJ/mole, 0.094 kJ/mole, and 35.03 kJ/mole, respectively. Accordingly, the introduced catalyst has a lower price with higher performance encouraging a practical sustainable H2 energy application from the chemical hydrogen storage materials.

The rheological model for yield stress exhibiting fluid and the basic laws for fluid flow and transport of heat and mass are used for the formulation of problems associated with the enhancement of heat and mass due to dispersion of nanoparticles in Casson. The heat and mass transfer obey non-Fourier's laws and the generalized Fick's law, respectively. Model problems are incorporated by thermal relaxation times for heat and mass. Transfer of heat energy and relaxation time are inversely proportional, and the same is the case for mass transport and concentration relaxation time. A porous medium force is responsible for controlling the momentum thickness. The yield stress parameter and diffusion of momentum in Casson fluid are noticed to be inversely proportional with each other. The concentration gradient enhances the energy transfer, and temperature gradient causes an enhancement diffusion of solute in Casson fluid. FEM provides convergent solutions. The relaxation time phenomenon is responsible for the restoration of thermal and solutal changes. Due to that, the thermal and solutal equilibrium states can be restored. The phenomenon of yield stress is responsible for controlling the momentum boundary layer thickness. A porous medium exerts a retarding force on the flow, and therefore, a deceleration in flow is observed. The thermal efficiency of MoS2-SiO2-Casson fluid is greater than the thermal efficiency of SiO2-Casson fluid.

The approaches used for the green biosynthesis of nanoparticles with clinical applications have been widely used in nanotechnology due to their potential to provide safe, eco-friendly, cost effective, high-stability, and high-loading-capacity nanoparticles. This study aimed to evaluate the anti-candidal activity of silver nanoparticles (AgNPs) biosynthesized using the aqueous leaf extract of Calotropis gigantea (CG) alone or in a combination with the plant extract of CG (AgNPs/CG). AgNPs were characterized using UV-Vis spectrophotometry, Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The results of the standard disk diffusion method revealed that AgNPs alone displayed anti-candidal activity (11.33-mm inhibition zone), while AgNPs/CG displayed a strong synergistic anti-candidal activity (17.76-mm inhibition zone). Similarly, AgNPs/CG completely inhibited the growth of C. albicans after 4 h of incubation, as measured using the time-kill assay. In addition, AgNPs/CG inhibited the dimorphic transition of C. albicans and suppressed both the adhesion and the biofilm formation of C. albicans by 41% and 38%, respectively. The treatment of Candida. albicans with AgNPs/CG showed a significant inhibition of the production of several antioxidant enzymes. Interestingly, AgNPs/CG did not show any cytotoxicity in animal cells, including the MCF-7 cell line and primary mouse bone marrow-derived mesenchymal stem cells (mBMSCs), at the concentration used to completely inhibit the dimorphic transition of C. albicans. In conclusion, we identified AgNPs/CG as a promising natural-product-based nanoparticle that can potentially be used as an anti-candidal drug.

New nanocomposites containing zirconium were synthesized using microwave irradiation. Their structure was confirmed by vibrating sample magnetometer (VSM) curves, X-ray diffraction (XRD) patterns, scanning electron microscope (SEM) and transmission electron microscopy (TEM) images, Fourier transform infrared spectroscopy (FT-IR), and Brunauer-Emmett-Teller (BET) N2 adsorption/desorption isotherms. After the structure confirmation of the zirconium magnetic nanocomposite, the catalytic properties in the synthesis of pyrazole derivatives were investigated. Next, the biological activities of the zirconium magnetic nanocomposite, such as the antibacterial and antifungal activities, were investigated. The research results showed that the zirconium magnetic nanocomposite has high catalytic properties and can be used as a magnetic nanocatalyst for synthesizing heterocyclic compounds such as pyrazole derivatives in addition to having high biological properties. The unique properties of the nanoparticles can be attributed to their synthesis method and microwave radiation.

Awareness about environmental concerns is increasing, specially the pollution resulting from nanoparticles (NPs) production, which has led to great interest in the usage of biogenic agents for their fabrication. The current investigation used eco-friendly organic phytomolecules from Leucophyllum frutescens and Russelia equisetiformis leaves extract for the first time in the fabrication of silver NPs from silver ions and further an assessment of their biological activities was performed. The leaves extract from both plant sources were used as capping and reducing agents and added to AgNO3. The mixtures were observed for colour changes, and after a stable dark brown colour was obtained, the NPs were separated and further investigated using dynamic light scattering, transmission electron microscopy and energy-dispersive X-ray spectroscopy. The Fourier transform infrared spectroscopy technique was employed to determine the active organic ingredients in the plant extracts. The prepared NPs were tested against three cell lines (two cancer ones and one normal control) and the effects observed using TEM and confocal laser scanning microscopy (LSM). Antibacterial activity against two Gram positive and two Gram negative species was examined and the synergistic effect of the ampicillin-NPs conjugate was studied. Findings showed successful conversion of Ag ions into L-AgNPs and R-AgNPs achieved using L.frutescens and R. equisetiformis extracts, respectively. A mean size of 112.9 nm for L-AgNPs and 151.7 nm for R-AgNPs and negative zeta potentials were noted. TEM analysis showed spherical NPs and EDS indicated Ag at 3 keV. Reduction in cancer cell viability with low half-maximal inhibitory concentrations was noted for both tested NPs. Structural changes and apoptotic features in the treated cancer cell lines were noted by TEM and cell death was confirmed by LSM. Furthermore, higher antibacterial activity was noticed against Gram positive compared with Gram negative bacteria as well as high synergistic effect was noted for the Amp-NPs conjugate, specially against Gram positive bacteria. The current investigation has thus developed an eco-friendly NPs synthesis route by applying plant extracts to efficiently produce NPs endowed with potential cytotoxic and antibacterial capacity, which therefore could be recommended as new approaches to overcome human diseases with minimal environmental impact.

Aspergillus fumigatus is one of the most common fungal pathogens that can cause a diversity of diseases ranging from invasive pulmonary aspergillosis (IPA) and aspergilloma to allergic syndromes. In this study, we investigated the antifungal effect of silver nanoparticles biosynthesized with Artemisia sieberi leaf extract (AS-AgNPs) against A. fumigatus in vitro and in vivo. The biosynthesized AS-AgNPs were characterized by imaging (transmission electron microscopy (TEM)), UV-VIS spectroscopy, X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The microdilution method showed the antifungal activity of AS-AgNPs against A. fumigatus, with an MIC of 128 µg/mL. AS-AgNPs significantly inhibited the growth of hyphae in all directions, as imaged by SEM. Additionally, TEM on biofilm revealed invaginations of the cell membrane, a change in the vacuolar system, and the presence of multilamellar bodies within vacuoles. Interestingly, AS-AgNPs displayed low cytotoxicity on the A549 human lung cell line in vitro. Treatment of an invasive pulmonary aspergillosis (IPA) mouse model with AS-AgNPs demonstrated the potency of AS-AgNPs to significantly reduce lung tissue damage and to suppress the elevated levels of pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-α), interleukin-1 (IL-1), and interleukin-17 (IL-17). The therapeutic potential of AS-AgNPs was found to be due to their direct action to suppress the fungal burden and gliotoxin production in the lungs. In addition, AS-AgNPs reduced the oxidative stress in the lungs by increasing the enzymatic activities of catalase (CAT) and superoxide dismutase (SOD). Thus, our data indicate the biosynthesized AS-AgNPs as a novel antifungal alternative treatment against aspergillosis.

The ZnO nanoparticle synthesis using the leaf part of Chamaecostus cuspidatus was characterized using UV-Vis spectrophotometry, IR, XRD, DLS, FESEM, EDX, TEM, AFM and XPS. The MTT assay was used to examine the cytotoxicity activity against lung epithelial and breast cell lines, and the IC50 value was determined. The presence of ZnO nanoparticles, which range in size from 200 to 800 nm, was confirmed by the absorption peak at 350 nm. The median particle size was 145.1 nm, and the ζ -the potential was -19.45 mV, showing that ZnONP is stable. Zinc, carbon, and oxygen contribute to the elemental composition of ZnONP, as determined by EDX analysis. MTT assay was used to investigate in vitro cytotoxicity in MCF-7 and A549 cell lines. The cytotoxicity activity IC50 value was determined to be 30 μg/mL for the A549 cell line and 37 μg/mL for the MCF-7 cell line.

Over the past few decades, there has been an increased trend for the use of natural compounds and their derivatives as alternatives to traditional chemicals and is due to their renewability, green character, and wide availability. This work aims to convert sodium alginate (S.ALG), a natural polysaccharide, into amides through its conversion to alginic acid (H.ALG). The formed H.ALG was esterified using methanol, followed by a reaction with octadecylamine (OA) and dodecylamine (DA) to produce corresponding amides, OA-ALG, and DA-ALG, respectively. The synthesized OA-ALG and DA-ALG were used as capping agents to further form hydrophobic magnetite nanoparticles (MNPs), OA-MNPs and DA-MNPs, respectively. The chemical structures, morphology, hydrophobicity, and magnetic properties of OA-MNPs and DA-MNPs were investigated using different instrumental techniques. Furthermore, the efficacy of as-synthesized MNPs as oil spill collectors were also evaluated using different ratios of MNPs:crude oil. From the analysis of results, the OA-MNPs and DA-MNPs exhibited high efficiency in the collection of oil spill even at low ratios of MNPs:crude oil.

A photocatalytic system for decolorization of double azo reactive black 5 (RB5) dye and water disinfection of E. coli was developed. Sol gel method was employed for the synthesis of Fe-TiO2 photocatalysts and were characterized using thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) coupled with energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS) and Brunauer-Emmett-Teller (BET) analysis. Results showed that photocatalytic efficiency was greatly influenced by 0.1 weight percent iron loading and 300 °C calcination temperature. The optimized reaction parameters were found to be the ambient temperature, working solution pH 6.2 and 1 mg g-1 dose to completely decolorize RB5. The isotherm studies showed that RB5 adsorption by Fe-TiO2 followed the Langmuir isotherm with maximum adsorption capacity of 42.7 mg g-1 and Kads 0.0079 L mg-1. Under illumination, the modified photocatalytic material had higher decolorization efficiency as compared to unmodified photocatalyst. Kinetic studies of the modified material under visible light irradiation indicated the reaction followed the pseudo-first-order kinetics. The illumination reaction followed the Langmuir-Hinshelwood (L-H) model as the rate of dye decolorization increased with an incremental increase in dye concentration. The L-H constant Kc was 1.5542 mg L-1∙h-1 while Kads was found 0.1317 L mg-1. The best photocatalyst showed prominent percent reduction of E. coli in 120 min. Finally, 0.1Fe-TiO2-300 could be an efficient photocatalyst and can provide a composite solution for RB5 decolorization and bacterial strain inhibition.

Despite many dedicated efforts, the fabrication of high-quality ZnO-incorporated Zinc@Silicon (Zn@Si) core-shell quantum dots (ZnSiQDs) with customized properties remains challenging. In this study, we report a new record for the brightness enhancement of ZnSiQDs prepared via a unified top-down and bottom-up strategy. The top-down approach was used to produce ZnSiQDs with uniform sizes and shapes, followed by the bottom-up method for their re-growth. The influence of various NH4OH contents (15 to 25 µL) on the morphology and optical characteristics of ZnSiQDs was investigated. The ZnSiQDs were obtained from the electrochemically etched porous Si (PSi) with Zn inclusion (ZnPSi), followed by the electropolishing and sonication in acetone. EFTEM micrographs of the samples prepared without and with NH4OH revealed the existence of spherical ZnSiQDs with a mean diameter of 1.22 to 7.4 nm, respectively. The emission spectra of the ZnSiQDs (excited by 365 nm) exhibited bright blue, green, orange-yellow, and red luminescence, indicating the uniform morphology related to the strong quantum confinement ZnSiQDs. In addition, the absorption and emission of the ZnSiQDs prepared with NH4OH were enhanced by 198.8% and 132.6%, respectively. The bandgap of the ZnSiQDs conditioned without and with NH4OH was approximately 3.6 and 2.3 eV, respectively.