Fold Enhancement Research Articles

Bandgap Modulation of Glancing Angle Deposition Aided Ag Nanoparticles Covered TiO₂ Thin Film by High Temperature Annealing.

Glancing Angle Deposition (GLAD) technique has been used to fabricate the Ag nanoparticles (NPs) over TiO₂ thin film (TF) on the n-Si substrate. The deposited Ag NPs are in the size of 3-5 nm. Open-air annealing has been done at 500 °C and 600 °C for the n-Si/TiO₂ TF/Ag NP samples. High Resolution X-ray Diffraction (HRXRD) peaks were identified to calculate the crystalline size of the NPs and rutile phase of the annealed sample were exhibited. Morphological analysis has been done for the sample using Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive Spectroscopy (EDS) and Atomic Force Microscopy (AFM). The enhancement of plasmonic absorption and modulation in the bandgap for the annealed Ag NPs surrounded TiO₂ TF has been verified by UV-Vis Spectroscopy and the bandgap has been calculated using Tauc plot. An overall 2.5 fold and 3 fold enhancement has been observed in the UV region and visible region for n-Si/TiO₂ TF/Ag NP annealed at 500 °C and 600 °C samples as compared to the n-Si/TiO₂ TF/Ag NP as-deposited samples. The modulation of bandgap due to the sub-band transition and Localized Surface Plasmon Resonance (LSPR) effect of Ag NPs and relevant sub-band transition due to change in annealing temperature has been reported.

RETRACTED ARTICLE: Homo and heterologous expression of the HpPKS2 gene in Hypericum perforatum and Bacopa monnieri

Hypericum perforatum has been known to produce hypericin and hyperforin that are used in treating mild to moderate depression. The HpPKS2 (H. perforatum polyketide synthase 2) gene is assumed to play a role in hypericin biosynthesis. The HpPKS2 gene was overexpressed in homologous H. perforatum in vitro grown plants through Agrobacterium tumefaciens-mediated genetic transformations. It leads to the establishment of seven glass house acclimatized transgenic lines. Among them, the HP12 transgenic plant showed 9.8 fold enhancement in hypericin content (379.4 ± 10.3 µg/g dry wt) followed by 3-fold in HP41 (117.1 ± 4.5 µg/g dry wt) as compared to control plants. This was further supported by the real-time PCR studies where it registered up to 5 fold enhancement of HpPKS2 gene expression. On the other hand, the heterologous expression of the HpPKS2 gene in Bacopa monnieri resulted in the establishment of five transgenic plant clones that were successfully acclimatized under glasshouse conditions. Among them, BT4 was found to be very slow-growing. The BT3 line showed maximum expression of the HpPKS2 gene which surprisingly also upregulates the expression of the other metabolic pathway genes of B. monierri namely isopentyl- diphosphate delta isomerase (IDDI), squaline synthase (SQS) and acetyl CoA C acetyltransferase (AA). The HPLC analysis in the heterologous system revealed the maximum production of bacopaside I (9.86 ± 1.0 mg/g dry wt), bacopaside II (5.89 ± 0.9 mg/g dry wt) and bacopasaponin C (3.59 ± 0.3 mg/g dry wt) by transgenic lines BT8, BT3 and BT4, respectively. This enhancement in bacopaside I, bacopaside II and bacopasaponin C production was more than 26-fold, 5-fold and 21-fold, respectively in comparison to the control non transformed plants. Overexpression of the HpPKS2 gene in H. perforatum led to higher hypericin content in the native system while its expression in the heterologous system i.e. B. monnieri also improves bacopaside I, bacopaside II and bacopasaponin C production.

In‐Syringe Electrokinetic Protein Removal from Biological Samples prior to Electrospray Ionization Mass Spectrometry

AbstractHere, an electrokinetic extraction (EkE) syringe is presented allowing for on‐line electrokinetic removal of serum proteins before ESI‐MS. The proposed concept is demonstrated by the determination of pharmaceuticals from human serum within minutes, with sample preparation limited to a 5× dilution of the sample in the background electrolyte (BGE) and application of voltage, both of which can be performed in‐syringe. Signal enhancements of 3.6–32 fold relative to direct infusion of diluted serum and up to 10.8 fold enhancement, were obtained for basic and acidic pharmaceuticals, respectively. Linear correlations for the basic drugs by EkE‐ESI‐MS/MS were achieved, covering the necessary clinical range with LOQs of 5.3, 7.8, 6.1, and 17.8 ng mL−1 for clomipramine, chlorphenamine, pindolol, and atenolol, respectively. For the acidic drugs, the EkE‐ESI‐MS LOQs were 3.1 μg mL−1 and 2.9 μg mL−1 for naproxen and paracetamol, respectively. The EkE‐ESI‐MS and EkE‐ESI‐MS/MS methods showed good accuracy (%found of 81 % to 120 %), precision (≤20 %), and linearity (r>0.997) for all the studied drugs in spiked serum samples.

Piezo-phototronic and plasmonic effect coupled Ag-NaNbO3 nanocomposite for enhanced photocatalytic and photoelectrochemical water splitting activity

Silver (Ag) nanoparticles decorated NaNbO3 nanorods (Ag-NaNbO3) based nanocomposite have been successfully synthesized by simple chemical solution method with the aim to couple the plasmonic and piezo-phototronic effect. The Ag-NaNbO3 nanocomposite showed much enhanced photocatalytic and photoelectrochemical water splitting properties as compared to bare NaNbO3. A ∼10 fold enhancement in the photodecomposition of organic MB dye and a ∼9 fold increment in the photocurrent density of photoelectrochemical water splitting was observed as compared to bare NaNbO3, which has been attributed to the combined plasmonic and piezo-phototronic effect. The plasmonic effect due to the presence of Ag nanoparticles on the NaNbO3 surface resulted in enhanced absorption of visible light and piezo-photoelectric effect resulted in better separation of the photogenerated charges due to the built-in electric field. This approach demonstrates a novel strategy for enhancing the performance of silver decorated semiconducting/piezoelectric material for achieving efficient photocatalytic dye degradation and PEC water splitting.

Synthesis and catalytic performance of zeolite-Y supported on silicon carbide in n-heptane cracking

In this work, we demonstrate a facile approach for the synthesis of zeolite-Y crystals (size, ca. ∼400 nm) supported on silicon carbide (SiC) with the assistance of the cationic template (polydiallyldimethylammonium chloride, PDDA). The polymeric cationic template used to treat SiC particles induces a positive charge on SiC surface which electrostatically attracts negatively charged aluminosilicate seeds and promotes the growth of zeolite (ZY) particles over SiC, thus leading to the formation of stable ZY@SiC supported catalysts. The supported ZY catalysts with different weight ratio of ZY and SiC were synthesized and characterized by various techniques such as XRD, SEM, SEM-EDX, SEM-mapping, TEM, STEM, FT-IR, 27Al MAS NMR and N2 sorption. The characterization of the supported ZY catalysts suggests the uniform growth of ZY particles over SiC together with the creation of hierarchical micro-mesopores assembly. In the catalytic cracking of n-heptane, the catalyst ZY@SiC-50 displayed a remarkable improvement in reaction rate when compared to commercial zeolite-Y (CBV-600) amounting to 3.5 folds enhancement. Interestingly, the light olefins yield is also substantially improved. At WHSV of 8 h−1 and 475 °C, the highest light olefin yield (24–36 %) was achieved over ZY@SiC-50 whereas the reference catalyst, CBV-600 produced lower light olefins yield (7–17 %). Moreover, the supported ZY catalyst exhibited less deactivation rates. This improved performance is attributed to the hierarchical micro-mesopores assembly created by the homogeneous dispersion of zeolite crystals on SiC which offers fast diffusion pathways for the reactants and enhanced accessibility to active sites thus leading to higher observed reaction rates and fast diffusion of products thus minimizing the occurrence of side reactions.

Review of Social-Media Dissociation During COVID-19 Pandemic

The pervasive mental breakdown of COVID19 with compulsion of social distancing and isolation barricaded the human relation. This calamity has built up new rules in the society for survival of mankind. Compelling technological based interaction through social media as the safest mode of interaction. But excessive social media networking leads addiction, obsession and finally to depression respectively. As proven with previous literature, there is almost 50% surge in social media usage, resulting in three fold enhancement of depression during this pandemic. This review is attempted to emphasis, how excessive social media networking hampers mental well being of the community along with suggestive measure to overcome this issue.

Development and Optimization of Amoxicillin Floating Raft System to effectively treat Helicobacter pylori infection

Introduction: The aim of the present study was to develop and to characterize the Floating raft system (FRS) of Amoxicillin to enhance gastric residence time and drug release to target Helicobacter pylori effectively. Method: In the present study, guar gum, Glyceryl Monostearate (GMS), Calcium carbonate were selected as factors. Gelation duration (h), floating lag time (min), and % Cumulative drug release (CDR) were selected as responses. 23 factorial design with replicates was selected for experimentation. Results: It was observed that Guar gum and GMS were the major factors affecting gelation duration, increase in the quantity of both Guar gum and GMS increased gelation duration i.e., sustained gelation period (24 h). Floating time increased with an increase in the amount of guar gum and calcium carbonate, whereas an increase in the quantity of GMS decreased floating time. Guar gum, calcium carbonate, and GMS exhibited an antagonistic effect on % CDR. Contour plots were used to identify design space; further numerical analysis yielded 12 best solutions based on desirability. FRS exhibited greater AUCo-t, Cmax, tmax, and t1/2 when compared to marketed formulation approximately 2.30 folds enhancement and prolongation with a sustained release for greater than 24 h that might be due to better gelation. Conclusions: It can be concluded that the floating raft system was successfully developed by the Design of experiment (DoE) application with fewer trails and by utilizing easily available excipients for better floating, gelation, and sustained delivery of the drug.

β-cyclodextrin polymer/Soluplus® encapsulated Ebselen ternary complex (EβpolySol) as a potential therapy for vaginal candidiasis and pre-exposure prophylactic for HIV.

Epidemiological findings have discussed recurrent and persistent vulvovaginal candidiasis to be a major manifestation of HIV infected women. Conversely, women with vulvovaginal candidiasis have higher risk of acquiring HIV transmitted during intercourse. Common treatments for such conditions include combined antiretroviral and antifungal therapy. Drug-Drug interaction is a major problem encountered due to common CYP450 metabolic pathway of azoles and antiretroviral drugs. Ebselen (EB), lipophilic, organo-selenium compound has demonstrated promising anti-HIV and anti-fungal activity. The aim of current research was to develop and characterize a rapidly soluble and non-cytotoxic vaginal film of ebselen which could serve dual purpose of treating vulvovaginal candidiasis and pre-exposure prophylactic (PrEP) against HIV. Ebselen/cyclodextrin polymer/Soluplus® (1:10:10) ternary complex (EβpolySol) showed 200 fold enhancement in aqueous solubility and no degradation of EB in thermogravimetry analysis. EβpolySol film with tensile strength of 33.12±1.98N/cm2 disintegrated within 30 sec, presented instant drug release with no apparent precipitation in simulated vaginal fluid. EβpolySol film showed compatibility with HEC-1A monolayer and HeLa cells compared to VCF®. EβpolySol film showed MIC of 20μM against Candida species and IC50 of 0.71μM against HIV.

Preparation, optimization and preliminary pharmacokinetic study of curcumin encapsulated turmeric oil microemulsion in zebra fish

The present investigation aimed to develop curcumin loaded turmeric oil microemulsion for brain targeting. An effort has been made to investigate the role of functional components in developing brain targeted formulation which could enhance the bioavailability and uptake of drug in the brain upon oral administration. Preliminary studies like solubility study, emulsification study and construction of the pseudo ternary phase diagram were performed for screening components. The formulation was optimized by using extreme vertices mixture design. The optimized formulation was characterized for appearance, stability to centrifugation, dilution potential, globule size, zeta potential and drug content. Furthermore, ex-vivo permeation in chicken gut sac non everted technique and pharmacokinetic study in adult zebra fishes were carried out. The optimized formulation was found to clear, yellow-colored with the absence of phase separation and precipitation denoted the stability of formulation to centrifugation and dilution. The mean globule size, polydispersity index, zeta potential and drug content was observed as 29.13± 0.12 nm, 0.23 ± 0.01,-12.33 ± 1.37 mV and 99.10±3.91 %, respectively. Ex vivo permeation study revealed 2.41 fold enhancement in the steady-state flux when compared to curcumin solution. Furthermore, optimized formulation showed shorter Tmax (5 min) and higher AUC(0-∞) (7.93 μg/brain*min) compared to the curcumin solution which showed similar Tmax and AUC(0-∞) of 2.78 μg/brain*min after oral administration to zebra fishes revealing 3.97 fold enhancement. The results revealed enhanced ex vivo oral absorption and enhanced in vivo brain pharmacokinetics of curcumin via functional microemulsion in the zebra fish model.

Liposomes as carriers of resveratrol and vitamin E: Evaluating ameliorative antioxidant effect using chemical and cellular test systems.

Resveratrol (RES) in combination with antioxidant vitamins is reported to be more effective in protecting the cells from oxidative stress rather than any of these antioxidants alone. In continuation to our previous work using resveratrol and vitamin C, our main aim was to evaluate the antioxidant restorative effect using chemical and cellular test systems on resveratrol co-encapsulated vitamin E (VE) within liposomes. Z-average size was less than 135nm, polydispersity index<0.3; zeta potential>than±30mV and encapsulation efficiency of RES and VE>90% and 79% respectively. Chemiluminescence measurement indicated that the antioxidative activity of RES could be increased when VE was additionally loaded into liposomes. Inhibition of AAPH induced luminol enhanced chemiluminescence displayed 90% improvement (P<0.001) in comparison to control; on the other hand 70% luminescence inhibition of ROS production in isolated blood leukocytes (P<0.001) was observed. Intracellular oxygen-derived radicals measured by flow cytometry using 2'-7'-dichlorodihydrofluorescein diacetate demonstrated about 1.7 fold (P<0.05) and 1.5 fold (P<0.001) enhancement of radical scavenging activity in buffy coats under basal conditions and human umbilical vein endothelial cells after stimulation by H2O2 respectively. The cellular systems evidenced the ability of liposome loaded antioxidants to scavenge ROS in the extra and intracellular space, confirming enhanced antioxidative effectivity of RES in the presence of VE, which did not occur in combination with vitamin C. Hence it might be possible to improve the antioxidative effectivity of RES by other/additional antioxidants.

Boosting output performance of sliding mode triboelectric nanogenerator by charge space-accumulation effect

The sliding mode triboelectric nanogenerator (S-TENG) is an effective technology for in-plane low-frequency mechanical energy harvesting. However, as surface modification of tribo-materials and charge excitation strategies are not well applicable for this mode, output performance promotion of S-TENG has no breakthrough recently. Herein, we propose a new strategy by designing shielding layer and alternative blank-tribo-area enabled charge space-accumulation (CSA) for enormously improving the charge density of S-TENG. It is found that the shielding layer prevents the air breakdown on the interface of tribo-layers effectively and the blank-tribo-area with charge dissipation on its surface of tribo-material promotes charge accumulation. The charge space-accumulation mechanism is analyzed theoretically and verified by experiments. The charge density of CSA-S-TENG achieves a 2.3 fold enhancement (1.63 mC m−2) of normal S-TENG in ambient conditions. This work provides a deep understanding of the working mechanism of S-TENG and an effective strategy for promoting its output performance.

Surface polar charge induced Ni loaded CdS heterostructure nanorod for efficient photo-catalytic hydrogen evolution

Designing of artificial heterostructure photo-catalysts to crop solar energy for H2 evolution from water is of great importance nowadays. The ultrafine Ni (0.5, 1.0, 2.0 and 5.0 wt%) particles loaded CdS nanorods were synthesized by a simple chemical process. XRD shows the crystalline phase of CdS with increase in size from 17 to 28 nm with 10.19% and 10.06% enhancement in the lattice strain and the dislocation density for Ni (0.5–5.0 wt%). The XPS peaks observed at 854.88 eV and 861.07 eV for Ni2+ with energy separation of 6.18 eV confirmed the existence of NiO on Ni surface. The Raman bands for pure CdS and Ni (1.0 wt%)-CdS nanorods were observed at 300 cm−1 and 293 cm−1 for 1LO phonon and 601 cm−1 and 586 cm−1 for 2LO phonon, respectively. The Ni loading tuned the CdS band gap from 2.36 to 2.20 eV. The eight fold enhancement in the CdS specific surface area i.e., from 4.19194 m2 g−1 to 34.8343 m2 g−1 was achieved. After Ni loading, the synergetic effect of efficient electron separation and transportation was observed by the continuous quenching of luminescence emission intensity and the reduction of charge transfer resistance from 706 Ω for CdS to 484 Ω of CdS. The Ni (1.0 wt%)@ NiO optimal loading on CdS results highest photo-catalytic H2 evolution of 9.0 mmol at rate of 1.8 mmol h−1, which is about 50 times higher than that of 180 μmol at rate of 36 μmol h−1 for pure CdS. A thin layer of NiO on plasmonic Ni surface could be the promising system for photo-catalytic H2 evolution due to visible light photo-activity.

Organotrialkoxysilane-mediated controlled synthesis of noble metal nanoparticles and their impact on selective fluorescence enhancement and quenching

Ordered noble metal nanoparticles functionalized with organotrialkoxysilanes [e.g., 2-(3, 4-epoxycyclohexyl) ethyltrimethoxysilane (EETMS), 3-aminopropyltrimethoxysilane (APTMS), and 3-glycidoxypropyltrimethoxysilane (GPTMS)] were used as substrates to investigate the variation in fluorescence intensity of some well-known fluorophores (e.g., fluorescein, rhodamine, and l-tryptophan) based on distance effects and surface plasmonic activity. Anisotropic palladium nanoparticles (PdNPs), gold nanospheres (AuNPs), and silver nanospheres (AgNPs) were synthesized as a function of concentration of EETMS, APTMS, or GPTMS; the organotrialkoxysilane concentration directed the growth rate of particles along certain crystallographic facets. The reactive organic functionalities of alkoxysilanes facilitated the physisorption of probe molecules in proximity to the nanoparticles. The maximum enhancement in fluorescence intensity was observed in the case of APTMS-induced stabilization at hydrodynamic radii (RH) of ∼350 nm as a result of specific interactions with fluorescein molecules; quenching was mostly observed close for interactions between the GPTMS-functionalized nanoparticles and fluorophores. The smaller size of l-tryptophan and the absence of effective plasmonic coupling with PdNPs and AuNPs surfaces in the 290–370 nm emission range resulted in quenching; an appreciable far-field linking with AgNPs was noted around an emission wavelength of 360–375 nm, which resulted in several fold enhancement in intensity. Alkoxysilanes were shown to regulate the spatial control between the functionalized nanoparticles. As such nanoparticles, alkoxysilane-derived nanomaterials, may serve as promising platforms for metal enhanced fluorescence and fluorescence resonance energy transfer.

Development of sensitive analytical methods for the determination of thallium at trace levels by slotted quartz tube flame atomic absorption spectrometry

A simple, sensitive and economical technique is needed for the determination of thallium and this study demonstrates the different analytical strategies were developed using atomic absorption spectrometry (AAS). In order to improve the sensitivity of flame atomic absorption spectrometry (FAAS), a basic slotted quartz tube (SQT) was used for the thallium determination. In the first strategy, mixing propanol (100 μL) and Tl standard solution (500 μL) under the optimum conditions, namely solvent assisted SQT-FAAS, provided 4.49 folds enhancement in detection power with the help of better nebulization efficiency and/or atomization of analytes. Furthermore, SQT was used as an atom trap, AT as the second strategy. In this method, analyte atoms were trapped for 5.0 min on the SQT inner surface under the lean flame. In addition, a novel analytical method was developed using an inner surface coated SQT with metals with low volatility (palladium, tungsten, molybdenum, zirconium, tantalum, osmium and titanium). Under the all optimum conditions, limit of detection values were found to be 38 ng mL−1 and 3.5 ng mL−1 for SQT-AT-FAAS and Os-Coated-SQT-AT-FAAS methods, respectively. 319 folds improvement in detection power was obtained by Os-Coated-SQT-AT-FAAS method with respect to conventional FAAS.

A metal-enhanced fluorescence sensing platform for selective detection of picric acid in aqueous medium

Apart from national security and military purposes, it is also of great importance to detect picric acid (PA) in aqueous solution for pollution control. Herein, we report a gold nanoparticle (AuNP)-based sensor for detection of PA in aqueous condition, based on metal-enhanced fluorescence (MEF) of poly(allylamine)hydrochloride (PAH). Notable enhancement in fluorescence intensity is observed when PAH is incubated with Au@SiO2 nanoparticles, where silica shell controls the distance between gold core and PAH. Almost ∼280 fold enhancement is recorded when PAH is incubated with ∼45 nm diameter Au nanoparticles. A significant reduction in excited state lifetime followed the enhancement in fluorescence intensity, identifying the mechanism to be primarily obtained from the intrinsic radiative decay rate enhancement of PAH. The MEF sensor shows excellent selectivity for detection of PA in water, among similar electron deficient compounds via fluorescence quenching. The detection limit of the sensor is calculated to be 79 nM, in the linear range. Detection of PA is demonstrated in simulated water samples, where matrix effects are taken into account to assess the efficacy of the sensor.

Formulation of Ketoprofen Transdermal Solid Dispersion Patch as an Analgesic and Anti-Inflammatory

Objective: to formulate transdermal patches of ketoprofen solid dispersions, determine the effect of propylene glycol on the rate of release of ketoprofen transdermal solid dispersion patches to know the optimum transdermal patch form of a solid dispersion of ketoprofen could provided better analgesic and antiinflammatory effects compared to the trademark ketoprofen gel (Kaltrofen®).&#x0D; Design: this research was conducted using a transdermal experiment of dense solid dispersion patches of ketoprofen with variations in the amount of propylene glycol F1 (10%), F2 (20%) and F3(30%) , physicochemical characteristics (organoleptic, fiber, weight uniformity, folding enhancement and development), diffraction patterns (XRD), incompatibility patterns (FTIR), in vitro penetration testing. -vitro, evaluation of analgesic and anti-inflammatory activity.&#x0D; Interventions: the intervened variable were the in vitro penetration testing. In-vitro, evaluation of analgesic and anti-inflammatory effect of ketoprofen transdermal solid dispersion patch.&#x0D; Main outcome measures: the main measurement in this study were physicochemical characteristics (organoleptic, fiber, weight uniformity, folding enhancement and development), diffraction patterns (XRD), incompatibility patterns (FTIR), in vitro penetration testing. -vitro, evaluation of analgesic and anti-inflammatory activity.&#x0D; Results: transdermal patches of ketoprofen solid dispersion patches produce white, odorless preparations that have a flat surface, thickness between 0.0242 ± 0.0002 to 0.0269 ± 0.0003, weight uniformity 321.50 ± 0.78 to 381.54 ± 0.60, folding resistance between 375 ± 0.58 to 443 ± 1.53, all formulas already meet the requirements of physicochemical characteristics. F3 ketoprofen transdermal solid dispersion patch had a highest penetration degree and provide better analgesic effects compared to the trademark ketoprofen gel (Kaltrofen®), and there were significant differences between groups (p&gt;0.05).&#x0D; Conclusion: it can be concluded that the use of 30% propylene glycol in F3 ketoprofen transdermal solid dispersion patch affects the rate of drug release and had a better anti-inflammatory effect compared to the trademark ketoprofen gel (Kaltrofen®).&#x0D; &#x0D;

Tuning semiconductor LaFe0.65Ti0.35O3-δ to fast ionic transport for advanced ceramics fuel cells

Heterostructure and their associated properties like band energy, band bending, and interface play a vital role in the conduction of charge carriers. Enhancement of ionic conductivity has been observed by the semiconductor SrTiO3 and ionic conductor heterostructure formation, such insightful effect may be beneficial for electrolyte application in solid oxide fuel cells. Herein we report the formation of semiconductor and ionic materials heterostructure of LaFe0.65Ti0.35O3-δ (LFT) and Sm and Ca co-doped cerium oxide Ce0.8Sm0.05Ca0.15O2-δ (SCDC) with three folds enhancement in the ionic conductivity. When LFT-SCDC heterostructure was applied in the fuel cell, LFT-SCDC work as a good electrolyte and achieve a maximum power output density of 0.98 W/cm2. LFT-SCDC maintains the ionic and electronic conduction, the presence of electrons, their blockage and the fast promotion of ion transport play a key role in physical interpretation in realizing outstanding performance and understanding the mechanism of semiconductor electrolyte ceramics fuel cells. The constructed heterostructure between two different constituent phases of LFT and SCDC has established strong band bending at heterointerface, leading to the fast ionic transport in the interface. The combination of UV–visible spectroscopy and ultraviolet photoelectron spectroscopy (UPS) determine the band structure of both constituents, where the creation of oxygen vacancies are supported by X-ray photoelectron spectroscopy (XPS). It is revealed by the various investigation of electrical properties of LFT-SCDC heterostructure that it has both electronic and ionic behavior, where the built-in electric field formed by band energy alignment helps to enhance the transport of ions.

Enhancement of photocatalytic pollutant decomposition efficiency of surface mounted TiO2 via lithographic surface patterning

Abstract Titanium dioxide (TiO2) based photocatalysis has been among the most popular advanced oxidation processes in environmental applications in past several decades due to its low cost, nontoxicity, and relatively high oxidizing ability, although suffering from relatively low pollutant decomposition efficiency. Here we present a study on the enhancement of efficiency of thin TiO2 film produced by reactive magnetron sputtering on an interference lithography-processed support, thus increasing the surface area. The efficiency of differently patterned samples was demonstrated by decolorization of methylene blue. The three fold enhancement of the photocatalytic efficiency was observed due to surface area enlargement, and additionally due to multiple UV light reflections.

Zirconium nanoparticles based dispersive solid phase extraction prior to slotted quartz tube-flame atomic absorption spectrophotometry for the determination of selenium in green tea samples

In this study, a novel, easy, rapid and green zirconium nanoparticles (Zr-NPs) based dispersive solid phase extraction (DSPE) method is presented for the precise and sensitive determination of selenium by slotted quartz tube-flame atomic absorption spectrophotometry (SQT-FAAS). Influential parameters of the extraction procedure were optimized by altering one parameter while keeping the other parameters constant. The optimum conditions were selected as 10mg of Zr-NPs, 75s vortex period, and 200µL of concentrated HCl for 30mL of sample/standard solution. The linear range of the developed method was found to be between 25 and 100µg/L, and the respective limits of detection and quantification were 5.3 and 18µg/L. About 415 folds enhancement in detection power was achieved by the optimized method relative to the conventional FAAS. Green tea samples were spiked and used for recovery experiments and the results obtained were between 92 and 102%.

PtRhCu ternary alloy nanodendrites with enhanced catalytic activity and durability toward methanol electro-oxidation

Despite the great progress has been made in the research of Pt-based catalysts toward methanol oxidation reaction (MOR), it is still remaining a great challenge for direct methanol fuel cells (DMFCs) to simultaneously satisfy both excellent activity and good durability. Herein, we report a facile one-pot approach for the successful fabrication of PtRhCu ternary alloy nanodendrites. For the methanol oxidation reaction (MOR), the electrocatalytic performances of the as-prepared nanocrystals can be optimized by simply varying the amount of Rh precursor. The mass activity and specific activity of the as-obtained Pt47Rh8Cu45 nanodendrites are 2.9 and 5.8 times as high as that of commercial Pt/C catalyst, respectively. Besides, after the accelerated durability test (ADT) for 1500 cycles, the remaining specific activity of Pt47Rh8Cu45 nanodendrites is 7.8 folds enhancement compared to commercial Pt/C, indicating the excellent stability of the PtRhCu catalyst. We believe that the improved electrochemical activity and stability could be resulted from the highly dendritic nanostructure and the synergetic effect of the three metallic elements in the alloy.