UV-visible Studies Research Articles

Acoustic shock-pulse-induced tunable structural and optical properties of L-Histidine maleate single crystals for photonic applications

In this paper, a single crystal of L-histidine maleate (LHM) was grown using a slow evaporation solution process. A tabletop shock tube is used to generate shock pulses. Shock waves' impact on the optical and structural characteristics of the LHM single crystal was studied for 0, 1, 2, and 3 shock pulses with a Mach number of 1.7. Analytical methods such as Powder X-ray diffraction, Raman, UV–visible spectroscopy, and optical microscopic techniques were utilized to get a deep understanding of the shock pulse impact of the title crystals. The crystalline nature is observed to be increased at the third shocked condition, as shown by the Raman and PXRD data. The UV-visible studies infer the enhancement of the crystal's optical-transmittance at 3rd shocked condition. It is to be noted that, the difference between optical transmittance at the impact of 2nd and 3rd shock is almost 30 %. It is evident from the data that, the applied shock waves are capable of tuning the local crystalline perfection and the optical transmittance of the test crystals. The shock wave induced higher crystalline perfection and optical transmittance LHM crystal is strongly suggested to the non-linear optical applications.

Exploring the diverse performance of nickel and cobalt spinel ferrite nanoparticles in hazardous pollutant removal and gas sensing performance.

A simple sol-gel combustion process was employed for the creation of MFe2O4 (M=Ni, Co) nanoparticles. The synthesized nanoparticles, acting as both photocatalysts and gas sensors, were analyzed using various analytical techniques. MFe2O4 (M=Ni, Co) material improved the degradation of methylene blue (MB) under UV-light irradiation, serving as an enhanced electron transport medium. UV-vis studies demonstrated that NiFe2O4 achieved a 60% degradation, while CoFe2O4 nanostructure exhibited a 76% degradation efficacy in the MB dye removal process. Furthermore, MFe2O4 (M=Ni, Co) demonstrated chemosensitive-type sensor capabilities at ambient temperature. The sensor response and recovery times for CoFe2O4 at a concentration of 100ppm were 15 and 20, respectively. Overall, the synthesis of MFe2O4 (M=Ni, Co) holds the potential to significantly improve the photocatalytic and gas sensing properties, particularly enhancing the performance of CoFe2O4. The observed enhancements make honey MFe2O4 (M=Ni, Co) a preferable choice for environmental remediation applications.

Structures, electrical properties and catecholase-like activity of a series of new copper(II) coordination polymers supported by azido bridges

A series of new copper(II)-azido complexes of 1D polymeric chains of [Cu(L1)(μ1,3-N3)]n (1) and [Cu(L2)(μ1,3-N3)]n (2), and binuclear [Cu(L3)(μ1,1-N3)]2 (3) [HL1 = N-butyl-N-(5-bromosalcylidine)ethane-1,2-diamine, HL2 = N-butyl-N-(5-chlorosalcylidine)ethane-1,2-diamine, HL3 = N-butyl-N-(salcylidine)ethane-1,2-diamine] have been synthesized and characterized. Characterizations of 1–3 have been accomplished by usual physico-chemical techniques such as elemental analysis, FTIR, UV–vis and single crystal X-ray diffraction studies. X-ray diffraction analyses of 1 and 2 reveal that the monomeric units of 1D polymers are interconnected via the μ1,3-azido bridging. The coordination geometry around the copper(II) centers in 1 and 2 can be best described as distorted square pyramidal environments. Complex 3 shows a centrosymmetric structure with two copper(II) centers that are held together by μ1,1-azido bridging in a distorted square pyramidal environment. In the electrical studies of 1–3, both direct current (dc) and alternating current (ac) analyses have been carried out based on the metal-complex (1/2/3)-metal (M-S-M) structures. The sheet resistance of the deposited films and the metal-complex contact resistance are estimated by employing transfer length method (TLM) measurements. The dark current-voltage characteristics of Al-complex (1/2/3)-Al structures are analyzed by considering dual back-to-back Schottky barrier diode structure. The voltage variations of the device current under illumination (400–700 nm) clearly demonstrate the photo-sensitivity of these materials. The catalytic activities of 1–3 have been investigated towards aerial oxidation of 3,5-di-tert-butylcatechol. All three complexes exhibit potential catalytic effectiveness towards oxidation of 3,5-di-tert-butylcatechol (3,5-DTBC) to 3,5-di-tert-butyl-o-quinone (3,5-DTBQ) with turnover numbers 14.76, 33.92 and 81.02 h−1 for 1, 2 and 3, respectively.

Organic Photoredox-Catalyzed S-Trifluoromethylation of Aromatic and Heteroaromatic Thiols.

A visible-light-mediated trifluoromethylation protocol was developed for the conversion of (hetero)aromatic thiols to their respective S-trifluoromethylated derivatives employing trifluoromethanesulfonyl chloride (CF3SO2Cl) as a cost-effective source of trifluoromethyl radical (CF3·) and a highly reducing organophotocatalyst, 3DPA2FBN. The developed methodology is operationally simple, providing access to a diverse range of products in up to 92% yield. A plausible mechanism has been postulated based on preliminary mechanistic studies, including irradiation on/off, UV-vis studies, and radical trapping experiments.

Nitro-aniline based tripodal nitric oxide (NO) releasing molecule and light-triggered cytotoxicity in cancer cells

Trimesic acid-based novel tripodal nitric oxide (NO) donor Tris-NTA has been reported for the light-controlled NO release in organic and aqueous medium. Tris-NTA gradually releases NO in blue light (410 nm), the amount and rate of NO released can be easily modulated and controlled by merely varying the concentration of Tris-NTA and light. UV–Vis studies and Griess assay confirmed the effective steady and slow release of NO from the Tris-NTA. pH-dependent NO release studies confirm that NO release is relatively fast in at acidic medium compared to other conditions studied. Having three NO-releasing units in a single molecule, Tris-NTA was found to have a good quantum yield and fast NO release rate as compared to model compound 1 having only one NO donor. In vitro cytotoxicity tests demonstrate that the Tris-NTA is non-toxic to the cells up to the concentration of 20 μg/mL. However, Cell viability studies on human prostate cancer in the presence of light at different times suggest that the compound is toxic to the cancer cells DU145, only with light. The NO released from Tris-NTA is responsible for the cell death. Cytotoxicity result suggests that Tris-NTA could be a capable new NO donor for treating human prostate cancer.

Investigations on temperature dependent properties of spray deposited tin oxide thin films

The present study reported the temperature dependent properties of tin oxide (SnO2) thin films deposited by using conventional, cost effective and non-vacuum-based spray pyrolysis technique (SPT). The as deposited films were characterized by various characterization techniques such as X ray diffraction (XRD), UV-Vis spectroscopy and Scanning electron microscopy (SEM) to study their structural, optical and morphological properties respectively. XRD analysis revealed tetragonal rutile crystal structure of SnO2 with preferred orientation along (200) plane. The refinement of XRD data was also carried out by Rietveld refinement to obtain the fitting parameters, crystallite size and lattice parameters. UV-Vis study showed considerable change in optical absorbance and transmittance with change in substrate temperature. Effect of substrate temperature on film thickness, refractive index and band gap energy were determined by Swanepoel method and by Tauc’s plot respectively. The Urbach energy was also calculated and were correlated to the defects in SnO2 films. SEM micrograph showed the transformation from granules to nanospheres as a function of substrate temperature. Electrical properties were determined by Hall effect measurements which gives carrier concentration, electrical resistivity and mobility in the order of 1019-1020 /cm3, 10−2-10−3 Ω.cm and 4–23 cm2/Vs respectively.

Photocatalytic activity of ZnO doped Nano hydroxyapatite/GO derived from waste oyster shells for removal of Methylene blue.

Hydroxyapatite (HAp) stands as an inorganic compound, recognized as a non-toxic, bioactive ceramic, and its composition closely resembles that of bone material. In this study, nHAp was prepared from waste oyster shells, which are biowaste rich in calcium carbonate. nHAp with its unique catalytic property can be used as an adsorbent in various fields, including wastewater treatment. nHAp with an exceptional surface adsorbent with excellent chemical stability, enabling its catalytic function. Nano hydroxyapatite doped with Zinc oxide (ZnO) by wet chemical precipitation and made into a composite with Graphene oxide (GO) by modified hummers method followed by grinding, which was taken as 9:1 ratio (nHAp/ZnO and GO) of weight, enhances its tensile and mechanical strength. The energy band gap of nHAp photocatalyst was evaluated as 3.39eV and that of the in nHAp/ZnO/GO photocatalyst was narrowed to 1.77eV. The ternary nanocomposites are very efficient in generating the photogenerated electrons and holes, thereby improving the degradation potential of dye effluents to by-products such as CO2 and H2O. The nanocomposites photocatalyst were characterized by FTIR, XRD, SEM, TEM, EDS, XPS, DRS, and BET techniques. The UV-visible study shows the complete dye degradation efficiency of the prepared nanocomposites photocatalyst. In this study, the prepared nanocomposites nHAp/ZnO/GO have studied their efficiency for the removal of MB dye in a batch process by varying the dosage from 0.1 to 0.5g, and the effects of dosage variations, pH, kinetic, scavenger study were evaluated at a time interval of 30min. The removal of dye was found to be 99% at 150min of 0.3g dosage and pH = 12 is most favorable as it reached the same percentage at 90min. The as-prepared nanocomposite nHAp/ZnO/GO fits the kinetic rate constant equation and shows a pseudo-first-order reaction model. This study indicates the suitability for dye removal due to the synergistic effect and electrostatic interaction of the synthesized ternary nanocomposite, which shows the potential, socially active, low-cost-effective, eco-friendly, and safe for photocatalytic degradation of MB from wastewater.

Investigation on Hirshfeld surface analysis, molecular geometry, DFT, MEP, and molecular docking analysis on benzotriazole oxalate against SARS-CoV-2 virus

Investigation on DFT, Molecular docking, Hirshfeld surface analysis, ADME characteristics Molecular Geometry, FT-IR, MEP analysis, and UV–Vis studies of Benzotriazole oxalate (BTO) is discussed here. BTO belongs to the monoclinic system with space group P21/c. BTO is a tiny chemical that interacts well with the SARS-CoV-2, based on small molecule docking studies with the target protein. The estimated vibrational frequencies (Fourier Transforms –Infrared spectrum) of the BTO molecule are compared and it exhibits excellent agreement with the experiment. The strengthening of protein-ligand electrostatic interactions is made possible by MEP. Using a 2D fingerprint plot and Hirshfeld Surfaces, the chemical surface and hydrogen bonding interactions in the BTO crystal structure were located and examined. Density Functional Theory (DFT)-B3LYP calculations using the 6–31++G (d, p) basis set predict the optimal geometry, including the bond length and bond angle of BTO. The characteristics of absorption, distribution, metabolism, and excretion were examined using the preADMET web server.

Comparative study of eriochrome black T (EBT) dye adsorption utilizing direct growth of cost-effective efficient materials: S-doped ZnO nanoparticles, ultrathin nanoflakes, and nanowalls

In the present studies, zinc oxide (ZnO) nanoparticles were synthesized by the non-aqueous sol-gel route and incorporated with diverse amounts of the nonmetal element like sulfur with different concentration (1, 2, 4, and 6 wt%). Furthermore, the physicochemical properties of all synthesized nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), N2 adsorption/desorption isotherms, and ultra violate visible (UV-Vis) absorption spectra. Powder XRD analysis shows the formation of hexagonal wurtzite phase of ZnO and the incorporation of S atom in ZnO lattice was confirmed by the XPS analysis. FESEM results reveal that the synthesised S-doped (2, 6 wt%) ZnO samples possess the growth of 1D ultra-thin nanoflakes with sharp edge and vertically aligned 1D thin nanowalls morphology. Moreover, UV-Visible transmission spectral studies showed that the optical energy band gap of ZnO NPs were reduced by S doping. After that, pure ZnO, 1, 4, and 6 wt% S-containing ZnO samples were examined as for adsorption study of eriochrome black T (EBT) dye. Among the S-containing samples, 50 mg of the adsorbent, doped with 4 wt% S (4 wt% S-ZnO) could adsorb up to 95.13 % of EBT dye (15 ppm) in 90 min. Therefore, such a sulfure doped ZnO samples in the form of nanoparticles (NPs), nanoflakes (nanosheets) as well as nanowalls could be used as a promising material for the application in industrial wastewater treatment processes.

Implication of carbohydrazide chemosensors in selective sensing of Fe(III) and construction of molecular devices

Two new and two reference sensors L1-L2 and R1-R2, respectively, based on the hydrazide core were synthesized in good yields (70–86 %). A variety of analytical methods, including NMR, HRMS, and single-crystal XRD, were used to characterize these sensors. Cyclic voltammetry, UV–visible absorption, and emission spectroscopies were then used to confirm the electrochemical and photophysical characteristics of these sensors. Moreover, theoretical calculations at the level of DFT and TD-DFT were carried out to compare the experimental findings with the theoretical ones. The sensors were found to exhibit luminescence attributed to singlet ligand-centered (1LC) transitions. Based on their luminescent properties and the previous literature reports where structurally analogous sensors have been used for the detection of metal ions, these sensors were investigated as selective chemosensors for Fe(III) detection, with a "turn-off" fluorescence behaviour in a binding stoichiometry of 1:1 = sensor:M(III) [M = Fe(III)] with a limit of detection of 2.71–39 µM, or 0.15–2.81 ppm. The mechanistic details regarding the sensing of Fe(III) ion by the sensors was provided by NMR, IR, XPS and UV-visible absorption spectroscopic studies. To increase the usefulness of the sensors, L2 was also applied for the successful fabrication of the molecular logic gate and molecular lock keypad. Paper strip test and sensing of Fe(III) contaminated water by the sensors accounted for the practical applicability of the sensors in real life.

Evaluation and characterization of Vachellia leucophloea (Roxb.) Maslin, Seigler & Ebinger using phytochemical, antioxidant, GC-MS, antibacterial, and anticancer properties

Medicinal plants provide a diverse spectrum of biological compounds that have significant uses in medicine and the well-being of humans. Vachellia leucophloea is a widely recognized medicinal plant in India with a wide range of therapeutic characteristics. This tree has been used in traditional medicine to treat numerous types of ailments since ancient times. Vachellia leucophloea contributes a significant part in regulating the death of cancer cells despite causing no adverse effects. In this present study, the bark of V. leucophloea was subjected to phytochemical analysis, total antioxidant activity by phosphor-molybdenum method, and DPPH assay to detect the radical scavenging activity, total phenol content for determining the plant’s antioxidant activity. Antibacterial and antifungal activities were performed by the agar well diffusion method. UV-Vis, FTIR, GC-MS, and TLC studies were performed to confirm the presence of compounds. The extract was subjected to MIC and TVC studies in which the plant’s ability to inhibit bacterial growth can be determined. DNA fragmentation assay was also analyzed by agarose gel electrophoresis. MTT assay was performed to analyze the anticancer activity against the MCF-7 Cell Line.

Realization of CO2 gas sensors and broadband photodetectors using metal/high-k CeO2/p-Si heterojunction

Realization of high-k dielectric oxide material-based devices such as photodetectors (PDs)/gas sensors fabricated on silicon substrate seems to be the utmost promising as a cost-effective approach to use in next generation optoelectronic field. We have explored metal/CeO2/p-Si heterojunction to construct as a broadband (BB) PD and CO2 gas sensor device. The effect of post-annealing procedure on photodetection and CO2 gas sensing characteristics were correlated using AFM, XRD, XPS, Raman and UV–Vis studies. At 0 V bias, the fabricated as-deposited Au/CeO2/p-Si PD device exhibits outstanding performance with enhanced responsivity of 85 AW−1 (at 910 nm), detectivity of 1.36×1015 Jones (at 850 nm), EQE of 1.3×104 % (at 850 nm), faster rise and fall times of 124 ms and 107 ms (at 900 nm). On the other hand, the photodetection characteristic parameters were slightly deteriorated as a function of annealing with respect to the as-deposited device. One of the causes for this fact was attributed to the increase in rms surface roughness (AFM) and decrease in absorbance of CeO2 thin film (UV–Vis). Additionally, Ag/CeO2/p-Si heterojunction was studied as a CO2 gas sensor and evaluated response/recovery times as a function of CO2 gas concentration. Sensing responses of CeO2 as-deposited, CeO2-400, CeO2-500, CeO2-600 and CeO2-700 °C were around 58, 60, 62, 81 and 90 %, respectively, when exposed to 200 ppm of CO2. Thus, we validate that the prospect of integrating enhanced performance in BB PDs and CO2 gas sensors using metal/CeO2/p-Si heterojunction could serve as a basic building block in near future optoelectronic applications. Furthermore, the effect of post-annealing temperature on the morphological, structural, BB photodetection and CO2 gas sensing properties were discussed in detail.

Synthesis, structural characterization and antitrypanosomal activity of ferrocenyl-based imines with (2 or 4)-nitrophenyl-2-furan group

Two new metallocene complexes with formulation [Fe(η5-C5H5){(η5-C5H4)-NCH-2-C4H2O-(5-C6H4-2-NO2)}] (3) and [Fe(η5-C5H5){(η5-C5H4)-NCH-2-C4H2O-(5-C6H4-4-NO2)}] (4) have been synthesized and their antitrypanosomal activity has been evaluated. Complexes 3 and 4 were obtained by condensation reaction of ferrocenylamine (1) with respective 5-(2-nitrophenyl)-2-furancarboxaldehyde (2a) or 5-(4-nitrophenyl)-2-furancarboxaldehyde (2b). The complexes were fully characterized by spectroscopic techniques (FT-IR, 1H and 13C{1H} NMR, and HRMS), which confirm their correct obtainment. The crystal structures of 3 and 4 were also determined by single crystal X-ray diffraction. Furthermore, UV–visible studies revealed that compounds 3 and 4 exhibited suitable stability in DMSO:HEPES buffer solution (80:20) throughout 24 h. The in vitro antiparasitic activities of ferrocenyl imine derivatives 3 and 4 were assessed against two species of parasites, Trypanosoma cruzi (T. cruzi) and Trypanosoma brucei (T. brucei). The obtained results revealed that compound 3 (EC50 = 0.44 μM) exhibited nearly a 40-fold greater efficacy as an anti-T. brucei agent compared to derivative 4 (EC50 = 16.0 μM). Moreover, compound 3 demonstrated superior potency when compared with its organometallic analogs (EC50 = 2.42–13.3 μM), which were previously reported by our research group. Interestingly, the EC50 value of 3 was found to be 8 times greater than that of nifurtimox (EC50 = 3.56 μM). The cytotoxicity of the ferrocenyl imines was also evaluated on the L6 rat skeletal myoblast cell line.

A Comparative Study on the Degradation of Methylene Blue and Methyl Orange Dyes Under the Irradiation of Visible Light Using GO–CdO Nanocomposites

Cadmium oxide nanoparticles synthesized from alcoholic method using cadmium chloride monohydride and the composites with GO by simple dispersion method. Two nanocomposites with 5 Wt% and 10 Wt% loading of CdO over GO were prepared and named as GC1 and GC2 respectively. From XRD the CdO nanoparticles were of crystalline nature and were indexed to JCPDS card no: 05-0640 corresponding to Cubic lattice system. The particle like morphology of the CdO was confirmed by SEM and TEM. The decoration of monolayer GO sheets by CdO nanoparticles was unveiled through these studies. The Raman analysis reveals the presence of D and G peaks in the composites with an increased ID/IG ratio. UV-Vis study displays the absorption edge of CdO and a redshift is observed for GC2. From PL study, emission peak occurs at 358 nm for composites along with a quenching of intensity for GC2. The TG-DT analysis reveals the thermal stability of pristine and nanocomposites. Photocatalytic degradation of the as synthesized samples was studied for Methylene orange and Methylene blue dye using a Xenon lamp with 500 W. The degradation of the GC2 happens in 90 minutes with degradation efficiency 73% of was achieved for Methyl Orange dye. For Methylene blue the GC2 sample degrades only in 30 minutes with an efficiency of 94% was achieved.

Biosynthesis of silver nanoparticles using green tea leaf extract and their structural and optical analysis

In the present study, silver nanoparticles (Ag NPs) were synthesized by biosynthesis method using Green tea leaf extract. Biosynthesis is an easy, economical, and environmentally friendly method to prepare NPs. The synthesized NPs were characterized by using an X-ray diffraction spectrum (XRD), UV-Vis spectra, Tauc plot and Dynamic light scattering spectrum analysis. The XRD results of biosynthesized Ag NPs show that the particles are crystalline and face-cantered cubical in shape, with an average size of 14 nm. UV-visible spectra studies and Tauc plot analysis confirm the excellent optical properties of the Ag NPs. Due to these outstanding qualities, we anticipated that the use of green-produced Ag NPs would result in an exponential increase in various applications. Ag NPs exhibit cytotoxicity and anticancer characteristics, antibacterial, antioxidant, and antifungal activity.

Novel esters derived from 4-hydroxychalcones as potential sunscreens with antimicrobial action

Ten novel 4-esterchalcones, licochalcone analogues, were strategically synthesized to study the effect of electro-donating or electro-withdrawing substituents in the aryl enone moiety on their pharmacological and photoprotective properties. 4-Esterchalcones had their drug-like character evaluated, which demonstrated positive characteristics for the development of novel drug candidates. In the in vitro antimicrobial evaluation, isovaleryl 4-esterchalcones showed activity against strains of Staphylococcus aureus, Candida albicans and C. tropicalis with minimum inhibitory concentration (MIC) in the range of 2.64-3.32 µmol mL−1, and the isobutyryl 4-esterchalcone 5d (4’-Br) presented antimicrobial activity against all strains tested, with a MIC of 2.74 µmol mL−1. In the UV-Vis study, λ max were observed at 312-327 nm, the UVB range, mainly. The best SPF-UVB results ranged from 18.04 to 21.06, with high ε max values, indicating that 4-esterchalcones have the potential to act as sunscreens. Furthermore, along with the environmental concern, halogenated compounds demonstrated slightly toxic on Artemia salina.

Luciferase-Decorated Gold Nanorods as Dual-Modal Contrast Agents for Tumor-Targeted High-Performance Bioluminescence/Photoacoustic Imaging.

Gold nanorods (AuNRs) have been considered highly compelling materials for early cancer diagnosis and have aroused a burgeoning fascination among the biomedical sectors. By leveraging the versatile tunable optical properties of AuNRs, herein, we have developed a novel tumor-targeted dual-modal nanoprobe (FFA) that exhibits excellent bioluminescence and photoacoustic imaging performance for early tumor diagnosis. FFA has been synthesized by anchoring the recombinant bioluminescent firefly luciferase protein (Fluc) on the folate-conjugated AuNRs via the PEG linker. TEM images and UV-vis studies confirm the nanorod morphology and successful conjugation of the biomolecules to AuNRs. The nanoprobe FFA relies on the ability of the folate module to target the folate receptor-positive tumor cells actively, and simultaneously, the Fluc module facilitates excellent bioluminescent properties in physiological conditions. The success of chemical engineering in the present study enables stronger bioluminescent signals in the folate receptor-positive cells (Skov3, Hela, and MCF-7) than in folate receptor-negative cells (A549, 293T, MCF-10A, and HepG2). Additionally, the AuNRs induced strong photoacoustic conversion performance, enhancing the resolution of tumor imaging. No apparent toxicity was detected at the cellular and mouse tissue levels, manifesting the biocompatibility nature of the nanoprobe. Prompted by the positive merits of FFA, the in vivo animal studies were performed, and a notable enhancement was observed in the bioluminescent/photoacoustic intensity of the nanoprobe in the tumor region compared to that in the folate-blocking region. Therefore, this synergistic dual-modal bioluminescent and photoacoustic imaging platform holds great potential as a tumor-targeted contrast agent for early tumor diagnosis with high-performance imaging information.

Environmentally benign preparation of Ag nanoparticles & Ag-rGO nanocomposite and evaluation of their photocatalytic, sensing, antioxidant and antimicrobial activities

Environmental pollution and fossil fuel depletion are becoming major issues on a worldwide scale, posing serious threats to both the environment and human health. Finding effective and affordable pollution cleanup technologies as well as the alternate source of energy is very important. The present study is concerned with the synthesis of Ag nanoparticles and Ag-rGO composite employing environment affable and cost-effective green combustion method. The fuel used for the preparation of NPs was the Malus domastica juice. The synthesized materials were subjected for the characterization techniques like XRD, TEM, SEM, Raman and UV-Visible spectral studies. The synthesized nanocomposite was analyzed for photocatalytic dye degradation, electrochemical nitrate sensing, antibacterial as well as antioxidant activities. Ag-rGO degraded methylene blue dye completely by 70 min. Further, the material was subjected for recyclability test and it was efficient and stable upto 5th cycle. Effect of various parameters such as catalytic load, dye concentration and pH on efficiency of dye degradation was analyzed. Nitrite sensing studies revealed that the LOD was found to be 19.8 µg. Further, Ag-rGO exhibited antibacterial activity on Pseudomonas aeroginosa bacterial strain to a greater extent compared to all the other bacterial strains tested. The Ag-rGO nanocomposite was found to be the potent antioxidant with IC50 value of 1489 µg/mL. Therefore, this work exemplifies the easy and eco-friendly green synthetic route for the large-scale industrial production of versatile Ag-rGO nanocomposite.

Functionalized high entropy alloys with ZIF-8 and LDH nanolayers for next-generation drug eluting medical implants

In this study, high entropy alloys (HEA) were fabricated by mixing Ni, Co, Cr, Fe, and Mn powders and then subjected to spark plasma sintering (SPS). Samples were coated by Al-Zn-layered double hydroxide (LDH) nanoparticles (NPs), SiO2 coated Al-Zn-layered double hydroxide NPs (LDH@Sio2), and zeolite imidazole framework (ZIF-8 NPs) using the electrophoretic deposition (EPD) method. To enhance immune response, antiviral effects, and iron uptake, ascorbic acid was intercalated within LDHs and ZIF-8 NPs layers via the ion-exchange method. Microstructural properties were examined using the X-ray diffraction method (XRD), optical microscopy, and scanning electron microscopy (SEM). The corrosion behavior of the specimens was investigated by a potentiodynamic polarization scan (PDS). A UV–visible evaluation test was conducted to assess drug release from the coated samples. SEM images demonstrated a homogenous microstructural coating, and XRD results confirmed that successful incorporation of vitamin C into LDH NPs, as indicated by an increase in layer distance from 7.36 to 7.46 Å. UV–visible studies revealed that LDH@SiO2 NPs exhibited a vitamin C release rate exceeding 5% compared to other coatings. Cell adhesion and proliferation assays using the MTT assay further confirmed the biocompatibility of the samples and their appropriate biological response to MG63 cells.

Development of high-performance ultrafast photodetector using CsPbBr3 perovskite single crystal

Here, we have developed a high-performance photodetector with enhanced photoelectric conversion efficiency and rapid response kinetics using an inorganic CsPbBr3 perovskite single crystal (PSC). A large area of high-quality PSC has been synthesized using a novel modified inverse temperature crystallization (ITC) process. The formation of the single crystal of the CsPbBr3 perovskite in an orthorhombic phase was confirmed by the X-ray diffraction (XRD) spectra while the excellent light absorption characteristics are corroborated with UV-Vis studies. A proposed Metal-Semiconductor-Metal (M-S-M) photodetector device structure using the CsPbBr3 PSC (Au/CsPbBr3/Au) has been examined by using monochromatic light in a wavelength range of 350–700 nm. The PSC photodetector exhibits excellent spectral responsivity of ∼ 0.42 A/W, detectivity of 6.26 × 1010 Jones, and external quantum efficiency of ∼ 95% with an ultrafast response/recovery time of ∼ 40/35 ms. Such excellent results unveil a new perspective in the PSC-based next-generation optoelectronic devices.