Characterization Of Nanostructures Research Articles

Green auto-combustion synthesis and characterization of TmVO4 nanostructures in the presence carbohydrate sugars and their application as Visible-light photocatalyst

The development of photocatalysts with adequate functions, particularly in the visible range, is one of the most significant issues facing scientists since they are essential compounds for the protection of the environment. A primary objective of this work was to simplify the preparation of thulium vanadate (TmVO4) nanostructures in order to improve their photocatalytic efficiency. By using a facile auto-combustion route, this study presents a new method for fabricating TmVO4 nanostructures. In order to achieve the desired size and homogeneity of the products, multiple factors were considered. As part of these parameters, several saccharides, such as glucose, fructose, lactose, maltose, and cellulose are analyzed for the first time, as well as the calcination temperature and the molar ratio. Various dye types and dye concentrations were studied to enhance catalyst performance. According to the catalyst activity, TmVO4 was able to degrade 83.5% of the methyl violet (MV) after 90 min. TmVO4 was found to be stable in the recycle test, with an efficiency reduction of 14.6% after five cycles.

Block Copolymer-Templated Au@CdSe Core-Satellite Nanostructures with Solvent-Dependent Optical Properties

In the present work, we report the fabrication and characterization of well-defined core-satellite nanostructures. These nanostructures comprise block copolymer (BCP) micelles, containing a single gold nanoparticle (AuNP) in the core and multiple photoluminescent cadmium selenide (CdSe) quantum dots (QDs) attached to the micelle's coronal chains. The asymmetric polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) BCP was employed to develop these core-satellite nanostructures in a series of P4VP-selective alcoholic solvents. The BCP micelles were first prepared in 1-propanol and subsequently mixed with AuNPs, followed by gradual addition of CdSe QDs. This method resulted in the development of spherical micelles that contained a PS/Au core and a P4VP/CdSe shell. These core-satellite nanostructures, developed in different alcoholic solvents, were further employed for the time-resolved photoluminescence analysis. It was found that solvent-selective swelling of the core-satellite nanostructures tunes the distance between the QDs and AuNPs and modulates their Förster resonance energy transfer (FRET) behavior. The average lifetime of the donor emission varied from 12.3 to 10.3 nanoseconds (ns) with the change in the P4VP-selective solvent within the core-satellite nanostructures. Furthermore, the distances between the donor and acceptor were also calculated using efficiency measurements and corresponding Förster distances. The resulting core-satellite nanostructures hold promising potential in various fields, such as photonics, optoelectronics, and sensors that utilize the FRET process.

Improving graphenic quality by oxidative liberation of crosslinks in non-graphitizable carbons

This work assesses the potential for improving the crystallinity of non-graphitizable carbon materials by oxidative liberation of crosslinks. A model non-graphitizable carbon – sucrose char and two commercial carbon blacks of varied nanostructure have been used to study crystallinity improvements at two oxidative burnout levels. The virgin materials have been compared to their partially oxidized counterparts at a series of heat treatment temperatures using X-ray diffraction for bulk crystallinity analysis and high-resolution transmission electron microscopy for nanostructural characterization. Remarkable improvements were observed in the case of sucrose char where non-graphitizable sponge-like particles transformed into highly ordered graphenic flakes by the mechanism of oxidative liberation of crosslinks. The in-plane crystallite size and stacking height tripled after the liberation of the restrictive crosslinks. Molecular level changes after partial oxidation have been assessed using Raman spectroscopy while X-ray photoelectron spectroscopy is used to assess changes in elemental composition. Notable improvements were also observed in carbon blacks with the development of longer and lower tortuosity lamellae accompanied by expanded particle sizes. Fringe analysis algorithms have been applied to obtain lamellae statistics and highlight nuances in the nanostructure changes after partial oxidation and heat treatment.

High-throughput investigation of Cr-N cluster formation in Fe-35Ni-Cr system during low-temperature nitriding

The expanded austenite (γN) produced by low-temperature nitriding of austenitic stainless steels with a Cr content of 18–20 at% is conventionally regarded as a nitrogen-supersaturated fcc solid solution with Cr-N short-range ordering, while obvious clustering between Cr and N in γN was recently reported for a Fe-35Ni-10Cr (at%) alloy. To investigate the dependence of Cr-N cluster formation on Cr concentration in γN, a high-throughput approach is proposed in the present work where a diffusion couple of Fe-35Ni and Fe-35Ni-30Cr alloys was plasma-nitrided at 673 K for 30 h. Systematic nanostructure characterization of the γN conducted by transmission electron microscopy (TEM) and three-dimensional atom probe (3DAP) revealed the variations in nanosized Cr-N clustering as modulated structures with different Cr content. Considering a simultaneous concentration fluctuation of Cr and N, computational thermodynamics of chemical driving force, strain energy, and modulation wavelength for coherent spinodal were performed, and the results were consistent with observed nanostructure evolution. The nanostructures of γN in austenitic stainless steels were also understood as further increments of Cr and N from a moderate composition lowered the driving force. The spinodal decomposition is also promoted by increasing Ni content in the alloys.

Classification of FIB/SEM-tomography images for highly porous multiphase materials using random forest classifiers

FIB/SEM tomography represents an indispensable tool for the characterization of three-dimensional nanostructures in battery research and many other fields. However, contrast and 3D classification/reconstruction problems occur in many cases, which strongly limits the applicability of the technique especially on porous materials, like those used for electrode materials in batteries or fuel cells. Distinguishing the different components like active Li storage particles and carbon/binder materials is difficult and often prevents a reliable quantitative analysis of image data, or may even lead to wrong conclusions about structure-property relationships. In this contribution, we present a novel approach for data classification in three-dimensional image data obtained by FIB/SEM tomography and its applications to NMC battery electrode materials. We use two different image signals, namely the signal of the angled SE2 chamber detector and the Inlens detector signal, combine both signals and train a random forest, i.e. a particular machine learning algorithm. We demonstrate that this approach can overcome current limitations of existing techniques suitable for multi-phase measurements and that it allows for quantitative data reconstruction even where current state-of the art techniques fail, or demand for large training sets. This approach may yield as guideline for future research using FIB/SEM tomography.

Insights into the Synthesis Mechanisms of Ag-Cu3P-GaP Multicomponent Nanoparticles.

Metal-semiconductor nanoparticle heterostructures are exciting materials for photocatalytic applications. Phase and facet engineering are critical for designing highly efficient catalysts. Therefore, understanding processes occurring during the nanostructure synthesis is crucial to gain control over properties such as the surface and interface facets' orientations, morphology, and crystal structure. However, the characterization of nanostructures after the synthesis makes clarifying their formation mechanisms nontrivial and sometimes even impossible. In this study, we used an environmental transmission electron microscope with an integrated metal-organic chemical vapor deposition system to enlighten fundamental dynamic processes during the Ag-Cu3P-GaP nanoparticle synthesis using Ag-Cu3P seed particles. Our results reveal that the GaP phase nucleated at the Cu3P surface, and growth proceeded via a topotactic reaction involving counter-diffusion of Cu+ and Ga3+ cations. After the initial GaP growth steps, the Ag and Cu3P phases formed specific interfaces with the GaP growth front. GaP growth proceeded by a similar mechanism observed for the nucleation involving the diffusion of Cu atoms through/along the Ag phase toward other regions, followed by the redeposition of Cu3P at a specific Cu3P crystal facet, not in contact with the GaP phase. The Ag phase was essential for this process by acting as a medium enabling the efficient transport of Cu atoms away from and, simultaneously, Ga atoms toward the GaP-Cu3P interface. This study shows that enlightening fundamental processes is critical for progress in synthesizing phase- and facet-engineered multicomponent nanoparticles with tailored properties for specific applications, including catalysis.

Simple sonochemical synthesis, characterization of TmVO4 nanostructure in the presence of Schiff-base ligands and investigation of its potential in the removal of toxic dyes

Thulium vanadate (TmVO4) nanorods were successfully prepared by a simple sonochemical approach using Schiff-base ligands. Additionally, TmVO4 nanorods were employed as a photocatalyst. The most optimal crystal structure and morphology of TmVO4 have been determined and optimized by varying Schiff-base ligands, the molar ratio of H2Salen, the sonication time and power, and the calcination time. A Eriochrome Black T (EBT) analysis revealed that the specific surface area was 24.91 m2/g. A bandgap of 2.3 eV was determined by diffuse reflectance spectroscopy (DRS) spectroscopy, which makes this compound suitable for visible photocatalytic applications. In order to assess the photocatalytic performance under visible light, two anionic dyes (EBT) and cationic dyes (Methyl Violet (MV)) were used as models. A variety of factors have been studied in order to improve the efficiency of the photocatalytic reaction, including dye type, pH, dye concentration, and catalyst loading. Under visible light, the highest efficiency was achieved (97.7%) when 45 mg TmVO4 nanocatalysts were present in 10 ppm Eriochorome Black T at pH = 10.

An eco-friendly chitosan/cellulose acetate hybrid nanostructure containing Ziziphora clinopodioides essential oils for active food packaging applications

This work presents the fabrication and characterization of a hybrid nanostructure, Ziziphora clinopodioides essential oils (ZEO)-loaded chitosan nanoparticles (CSNPs-ZEO) embedded into cellulose acetate (CA) nanofibers (CA-CSNPs-ZEO). The CSNPs-ZEO were first synthesized through the ionic gelation method. Then, through simultaneous electrospraying and electrospinning processes, the nanoparticles were embedded in the CA nanofibers. The morphological and physicochemical characteristics of the prepared nanostructures were evaluated using different methods, including scanning electron microscopy (SEM), water vapor permeability (WVP), moisture content (MC), mechanical testing, differential scanning calorimetry (DSC), and release profile studies. The antibacterial activity of the nanostructures was explored on raw beef as a food model during 12 days of storage at 4 °C. The obtained results indicated the successful synthesis of CSNPs-ZEO nanoparticles with an average size of 267 ± 6 nm and their incorporation into the nanofibers matrix. Moreover, the CA-CSNPs-ZEO nanostructure showed a lower water vapor barrier and higher tensile strength compared with ZEO-loaded CA (CA-ZEO) nanofiber. The CA-CSNPs-ZEO nanostructure also exhibited strong antibacterial activity, which effectively extended the shelf-life of raw beef. The results demonstrated a strong potential for innovative hybrid nanostructures in active packaging to maintain the quality of perishable food products.

Green synthesis and characterization of NiFe2O4 nanostructure via hydrothermal method

In this paper nickel ferrite nanostructures fabricated via simple and green hydrothermal method using lemon juice. For the synthesis of NiFe2O4 nanoparticles, the materials were placed in the autoclave reactor for 2 and 12 hours. The morphology of particles was studied by scanning electron microscope (SEM). Although the NiFe2O4 nanoparticles after 2 h heating are agglomerated but increasing the heating time to 12 h leads to formation of sphere shape nano size particles. Crystal structure of nickel ferrite nanoparticles was investigated via X-ray diffraction pattern and crystallite size of particles was calculated using Debye-Scherrer formula. The magnetic hysteresis loop of the synthesized ferrite was studied by a vibration sample magnetometer (VSM). The magnetic parameters of remanance Mr, saturation magnetization Ms and coercivity Hc, increase as the synthesis time increases. The optical properties of NiFe2O4 were investigated by ultraviolet visible (UV-vis) spectra. The results show that the particles band gaps decreases with increasing the synthesis time.

Self-Aggregation in Aqueous Media of Amphiphilic Diblock and Random Block Copolymers Composed of Monomers with Long Side Chains.

Amphiphilic diblock copolymers and hydrophobically modified random block copolymers can self-assemble into different structures in a selective solvent. The formed structures depend on the copolymer properties, such as the ratio between the hydrophilic and the hydrophobic segments and their nature. In this work, we characterize by cryogenic transmission electron microscopy (cryo-TEM) and dynamic light scattering (DLS) the amphiphilic copolymers poly(2-dimethylamino ethyl methacrylate)-b-poly(lauryl methacrylate) (PDMAEMA-b-PLMA) and their quaternized derivatives QPDMAEMA-b-PLMA at different ratios between the hydrophilic and the hydrophobic segments. We present the various structures formed by these copolymers, including spherical and cylindrical micelles, as well as unilamellar and multilamellar vesicles. We also examined by these methods the random diblock copolymers poly(2-(dimethylamino) ethyl methacrylate)-b-poly(oligo(ethylene glycol) methyl ether methacrylate) (P(DMAEMA-co-Q6/12DMAEMA)-b-POEGMA), which are partially hydrophobically modified by iodohexane (Q6) or iodododecane (Q12). The polymers with a small POEGMA block did not form any specific nanostructure, while a polymer with a larger POEGMA block formed spherical and cylindrical micelles. This nanostructural characterization could lead to the efficient design and use of these polymers as carriers of hydrophobic or hydrophilic compounds for biomedical applications.

Synthesis and characterization of rare earth-doped zinc oxide nano structures

Pure and rare earth metal [cerium (Ce) and thorium (Th)-doped zinc oxide (ZnO)] nanostructures were prepared by solution combustion synthesis by making use of metal nitrates and glycine as precursors in alkaline medium. The average crystal size was examined using Powder X-Ray Diffraction (PXRD) which showed sizes of 45 nm for pure ZnO sample,17.9 nm and 20 nm for Ce and Th-doped ZnO samples respectively. Accordingly, the synthesized samples were confirmed to be polycrystalline from High-Resolution Transmission Electron Microscopy (HRTEM), Selected Area Electron Diffraction (SAED) and X-Ray Diffraction (XRD) analyses. Field Emission Scanning Electron Microscopy coupled with Energy Dispersive X-Ray Spectroscopy (FESEM / EDX) confirmed the existence of the respective components in the synthesized samples. The Ultra Violet – Visible - Near Infra-Red (UV – Vis - NIR) Spectroscopy showed the characteristic absorption spectra of the samples. The surface topography of the prepared samples was studied by Atomic Force Microscopy (AFM). To further confirm the chemical composition and binding energy, X-Ray Photoelectron Spectroscopy (XPS) was employed.

Superior photocatalytic performance and photo disinfection of bacteria of solvothermally synthesized mesoporous La-doped CeO2 under simulated visible light irradiation for wastewater treatment

A simple, cost-effective, and facile solvothermal approach has been adopted to synthesize mesoporous CeO2 nanostructures with varying La-doping (2, 4, and 6 mol%) concentrations. Photocatalytic and antibacterial performances are investigated against the inactivation of Escherichia coli and Bacillus licheniformis bacteria cells. Structural and microstructural characterizations of La-doped CeO2 nanostructures are performed by analyzing X-ray diffraction (XRD) data employing the Rietveld refinement method, scanning electron (SEM) and transmission electron microscopy (TEM) images, Brunauer–Emmett–Teller (BET), energy-dispersive X-ray (EDX), and X-ray photoelectron spectroscopy (XPS) spectra. Among three doped samples, the 4 mol% La-doped CeO2 (LCe4) has exhibited high oxygen and Ce3+ concentrations, high microstrain, small crystallite size, and lowest band gap energy, as are revealed by the analysis of XPS, UV–VIS absorption spectra, photoluminescence (PL) spectra, and Rietveld refinement result. The LCe4 sample with the highest number of oxygen vacancies and high surface area shows superior photocatalytic activity (∼95% Rhodamin B (RhB) degradation in 130 min, ∼70% Methylene Blue (MB) degradation within 30 min, and ∼95% phenol degradation in 180 min under solar radiation). It shows a striking photo-disinfection effect and enhanced antibacterial activity (almost identical to a pure drug) against gram-positive and gram-negative bacteria under visible light irradiation. This novel disinfection and catalytic property of the LCe4 sample is attributed to the mesoporous structure of materials and surface activity, which lowers the electron-hole recombination rate and transports more photogenerated electrons and holes. The nanostructured mesoporous LCe4 material has been used as an effective visible light-activated photocatalyst and photo disinfection for treating wastewater containing organic dyes and gram-negative and gram-positive bacteria.

Probing 3D magnetic nanostructures by dark-field magneto-optical Kerr effect

Magneto-optical techniques are key tools for the characterization of magnetic effects at a nanoscale. Here, we present the dark-field magneto-optical Kerr effect (DFMOKE), a technique we have recently developed for the characterization of three-dimensional magnetic nanostructures. We introduce the principles of DFMOKE, based on the separation of an incident beam into multiple reflected beams when focusing on a 3D nano-geometry. We show the key modifications needed in a standard focused MOKE magnetometer to perform these measurements. Finally, we showcase the power of this method by detecting the magnetic switching of a single tilted 3D nanowire, independently from the switching of a magnetic thin film that surrounds it. We obtain independent and simultaneous switching detection of the nanowire and the film for all nanowire dimensions investigated, allowing us to estimate a magnetic sensitivity of 7 × 10−15 A m2 for DFMOKE in the setup used. We conclude the article by providing perspectives of future avenues where DFMOKE can be a very powerful characterization tool in the future investigations of 3D magnetic nanostructures.

Integrated optical critical dimension metrology with Mueller matrix ellipsometry

Mueller matrix ellipsometry (MME) is commonly applied by the standalone instruments in semiconductor manufacturing process for films and nanostructures characterization. However, MME is rarely used in the integrated metrology optical critical dimension (IM OCD) tools due to the difficulty in extracting the parameters under varied azimuth angle conditions, which is induced by the rotation of R-θ wafer stage adapted to the restricted space. When the measurements on a same wafer are achieved under multiple azimuthal angles, the measured nanostructure parameters usually mismatch the baseline values provided by the manufacturer, and therefore lead to the unacceptable accuracy loss. In this paper, we propose an azimuthal sensitivity analysis and ridge regression algorithm (ASA-RR) to enable the MME-based IM OCD. The sensitivity to variability in azimuth angles is calculated by the local sensitivity analysis algorithm, and the result of which is applied as the weight factor for the spectrum input in the ridge regression. Experiments demonstrate that the ASA-RR algorithm provides more accurate results for the IM OCD, which satisfy the requirements in manufacturing.

γ-Cyclodextrin-graphene quantum dots-chitosan modified screen-printed electrode for sensing of fluoroquinolones

An innovative electrochemical approach based on screen-printed carbon electrodes (SPCEs) modified with graphene quantum dots (GQDs) functionalized with γ-cyclodextrin (γ-CD) and assembled to chitosan (CHI) is designed for the assessment of the total content of fluoroquinolones (FQs) in animal source products. For the design of the bionanocomposite, carboxylated graphene quantum dots synthesized from uric acid as precursor were functionalized with γ-CD using succinic acid as a linker. Physic-chemical and nanostructural characterization of the ensuing nanoparticles was performed by high-resolution transmission scanning microscopy, dynamic light scattering, Z potential measurement, Fourier transformed infrared spectroscopy and X-ray diffraction. Electrochemical properties of assembled bionanocomposite like potential difference, kinetic electronic transfer constant and electroactive area among other parameters were assessed by cyclic voltammetry and differential pulse voltammetry using potassium ferricyanide as redox probe. The oxidation behaviour of four representative quinolones with distinctive structures was studied, obtaining in all cases the same number of involved e− (2) and H+ (2) in their oxidation. These results led us to propose a single and consistent oxidation mechanism for all the checked analytes. The γ-CD-GQDs-CHI/SPCE sensor displayed a boosted electroanalytical performance in terms of linear range (4–250 µM), sensibility (LOD = 1.2 µM) and selectivity. This electrochemical strategy allowed the determination of FQs total amount in complex processed food like broths, bouillon cubes and milkshakes at three concentration levels (150, 75 and 37.5 µM) for both equimolar and different ratio FQs mixtures with recovery values ranging from 90 to 106%.Graphical abstract

Directional fabrication and dissolution of larval and juvenile oyster shells under ocean acidification.

Biomineralization is one of the key biochemical processes in calcifying bivalve species such as oysters that is affected by ocean acidification (OA). Larval life stages of oysters are made of aragonite crystals whereas the adults are made of calcite and/or aragonite. Though both calcite and aragonite are crystal polymorphs of calcium carbonate, they have different mechanical properties and hence it is important to study the micro and nano structure of different life stages of oyster shells under OA to understand the mechanisms by which OA affects biomineralization ontogeny. Here, we have studied the larval and juvenile life stages of an economically and ecologically important estuarine oyster species, Crassostrea hongkongensis, under OA with focus over shell fabrication under OA (pHNBS 7.4). We also look at the effect of parental exposure to OA on larvae and juvenile microstructure. The micro and nanostructure characterization reveals directional fabrication of oyster shells, with more organized structure as biomineralization progresses. Under OA, both the larval and juvenile stages show directional dissolution, i.e. the earlier formed shell layers undergo dissolution at first, owing to longer exposure time. Despite dissolution, the micro and nanostructure of the shell remains unaffected under OA, irrespective of parental exposure history.

Hydrated MoO3 nanoparticles and α-MoO3 nanosheets synthesis by fs laser irradiation

We present a study of the synthesis and characterization of molybdenum oxide nanostructures produced by laser ablation of solids in liquids (LASL). A high purity molybdenum target was ablated in deionized water using femtosecond laser pulses. We found that both nanoparticles and nanosheets composed of molybdenum oxide were formed. The colloid suspension optical absorbance changes with time, as the colloid ages it changes color; a blue shift is observed within a few days of aging. It results in a band gap increase from 2.55 eV up to 2.9 eV for nearly a month of aging, which we computed through the Tauc method. Raman characterization of the nanostructures shows that the synthesized material turns into a hydrated molybdenum oxide (MoO3·nH2O). This is consistent with the band gap evolution, which for early aging corresponds to MoO3 to later achieve the band gap value of a hydrated molybdenum oxide. The nanostructures were also characterized by transmission electron microscopy (TEM) showing that the nanoparticles have a core-shell structure with a raspberry-like shell for medium and small nanoparticles and a smooth homogeneous shell for large nanoparticles. The size distribution peaks at 30–40 nm, with the smallest nanoparticles at 10 nm and the largest at 120 nm. The nanosheets are decorated by tiny nanoparticles. High resolution transmission electron microscopy (HRTEM) images allowed measuring the interplanar distances at the nanosheets, we found the nanosheets are composed by the orthorhombic stable-phase α-MoO3. SAED measurements confirmed the formation of this molybdenum oxide phase. An absorption band at 830 nm that develops in the few first days of aging of the colloid is of interest for photothermal therapy, which gives the reported nanostructures a good potential for biomedical applications.

Al-Doped ZnO Thin Films with 80% Average Transmittance and 32 Ohms per Square Sheet Resistance: A Genuine Alternative to Commercial High-Performance Indium Tin Oxide

In this study, a low-sophistication low-cost spray pyrolysis system built by undergraduate students is used to grow aluminum-doped zinc oxide thin films (ZnO:Al). The pyrolysis system was able to grow polycrystalline ZnO:Al with a hexagonal wurtzite structure preferentially oriented on the c-axis, corresponding to a hexagonal wurtzite structure, and exceptional reproducibility. The ZnO:Al films were studied as transparent conductive oxides (TCOs). Our best ZnO:Al TCO are found to exhibit an 80% average transmittance in the visible range of the electromagnetic spectrum, a sheet resistance of 32 Ω/□, and an optical bandgap of 3.38 eV. After an extensive optical and nanostructural characterization, we determined that the TCOs used are only 4% less efficient than the best ZnO:Al TCOs reported in the literature. This latter, without neglecting that literature-ZnO:Al TCOs, have been grown by sophisticated deposition techniques such as magnetron sputtering. Consequently, we estimate that our ZnO:Al TCOs can be considered an authentic alternative to high-performance aluminum-doped zinc oxide or indium tin oxide TCOs grown through more sophisticated equipment.

Green synthesis and characterizations of bi-functional Mo-doped ZnO nanostructures for antimicrobial and photocatalytic applications

The preparation of effective and excellent antimicrobial agent is becoming a severe issue from last few decades against human tested bacteria. Also, the polluted wastewater from industries severely required a sophisticated photocatalyst. Beside of all other semiconductor oxides, ZnO gained the great attention because of its unique and versatile antimicrobial and photocatalytic properties. In this work, its antimicrobial and photocatalytic nature is improved by preparing using green synthesis approach i.e extract of moringa oleifera seeds as these are naturally anti-oxidizing and antimicrobial agents. The XRD spectroscopic tool was used to reveal the structural properties of as prepared samples. SEM and HRTEM techniques were employed for in depth morphological study. EDX analysis tool was employed to check the purity and for compositional analysis of samples. For further structural study, SAED technique was also employed. UV–vis and PL tools were used to investigate the optical properties and recombination rates of charge carriers. The as developed nanostructures possessing much reduced grain sizes have significantly improved the antibacterial and photocatalytic performance of ZnO based samples by offering much enhanced active surface area and active sites for their working. The charge carriers’ dynamics was evaluated by studying EIS and photocurrent intensity response by as prepared samples. The green synthesized Mo doped ZnO has exhibited a reduced band gap i.e 3.11 eV than 3.25 eV offered by pure ZnO. The antimicrobial activity against B. subtilis and E. coli bacteria explored that the as green synthesized Mo doped ZnO nanomaterial was very competent for the inhibition of bacterial growth. Moreover, this green Mo-doped ZnO sample has also exhibited its excellent photocatalytic nature against a well-known rhodamine-B water pollutant by degrading its 89.6% just after 180 min. Also, this sample has shown good catalytic stability i.e 81 %. The reproducibility of the samples was made sure by preparing batches of three samples and taking the best out of them showing very small performance error. These superior antimicrobial and photocatalytic properties shown by green synthesized Mo-doped ZnO have opened new platform for bacteria inhibition and water purification applications.

Binding and Characterization of DNA Origami Nanostructures on Lipid Membranes.

DNA origami is an extremely versatile nanoengineering tool with widespread applicability in various fields of research, including membrane physiology and biophysics. The possibility to easily modify DNA strands with lipophilic moieties enabled the recent development of a variety of membrane-active DNA origami devices. Biological membranes, as the core barriers of the cells, display vital structural and functional roles. Therefore, lipid bilayers are widely popular targets of DNA origami nanotechnology for synthetic biology and biomedical applications. In this chapter, we summarize the typical experimental methods used to investigate the interaction of DNA origami with synthetic membrane models. Herein, we present detailed protocols for the production of lipid model membranes and characterization of membrane-targeted DNA origami nanostructures using different microscopy approaches.