Electrochemical heavy metal detection, photocatalytic, photoluminescence, biodiesel production and antibacterial activities of Ag�ZnO nanomaterial

Zinc oxide nanoparticles (ZnO Nps) and silver doped zinc oxide nanoparticles (Ag�ZnO Nps) were prepared using nitrates of zinc and silver as oxidizers and succinic acid as a fuel through solution combustion synthesis (SCS) at 400 °C. The synthesized materials were characterized by various analytical techniques such as XRD, FTIR, Raman UV�vis, PL, SEM, EDX and TEM. The synthesized nanomaterials were tested for the photocatalytic degradation of methylene blue and the result reveal that Ag�ZnO Nps shows the better photocatalytic activity compared to undoped ZnO Nps. Biodiesel production from Simarouba oil shows that Ag�ZnO Nps acts as good catalyst compare to ZnO Nps, we have also developed sensor which showed a linearity in the concentration range 50�350 nM and limit of detection was found to be 3.5 and 3.8 nM (3�) for lead and cadmium respectively. Further we have examined the antibacterial activity against Escherichia coli and Staphylococcus aureus bacteria. © 2017 Elsevier Lt

High capacity MoO3/rGO nanocomposite anode for lithium ion batteries: an intuition into the conversion mechanism of MoO3

MoO3 is a potential anode material for Li-ion batteries (LIBs) because of its high theoretical capacity (1117 mA h g(-1)). The major hurdles in realizing this high capacity are its low conductivity and large volume variations during intercalation/de-intercalation processes. To mitigate these shortcomings, we have synthesized reduced graphene oxide (rGO) wrapped MoO3 nanoparticles (NPs). This involves the synthesis of MoO3 NPs as the first step and then subjecting the synthesized MoO3 NPs to hydrothermal treatment along with graphene oxide (GO) sheets to form rGO wrapped MoO3 NPs. Electrochemical impedance spectra show that a 13% MoO3/rGO nanocomposite has the least conductive resistance among the different nanocomposites. Several physicochemical characterization techniques have been used to confirm the desired state of the obtained material. Ex-XRD studies were carried out to inspect the mechanism of MoO3 and found that it initially follows a simple lithiation/delithiation mechanism and later it adopts a conversion mechanism. The new architecture exhibits an excellent electrochemical performance by displaying a high first specific discharge capacity value (984 mA h g(-1)) and remarkable stability (901 mA h g(-1) even after 100 cycles)

Novel aggregation induced emission based 7-(diethylamino)-3-(4-nitrophenyl)-2H-chromen-2-one for forensic and OLEDs applications

In this report, a novel solvatochromism, aggregation induced emission (AIE) based 7-(diethylamino)-3-(4-nitrophenyl)-2H-chromen-2-one fluorescent probe (CFP) was synthesizes via one-pot multi-component reaction system under ultrasonication method. The synthesized CFP was characterized using different instrumental techniques namely, Fourier transform infrared spectroscopy (FTIR), Proton nuclear magnetic resonance spectroscopy (1H NMR), Mass spectrometer, Scanning electron microscope (SEM), Energy dispersive X-ray analysis (EDAX), Thermal gravimetric analysis (TGA), Transmission electron microscopy (TEM), UV−Vis spectrometry and Fluorescence spectrophotometer. The synthesized CFP produces red emission in solid as well as in liquid state. The synthesized CFP was investigated as a new labeling mediator for the visualization of latent fingerprints (LFPs) on the different non-porous materials surface. The obtained CIE result proves that the organic moiety was extremely helpful for the fabrication of red-light emitting diodes in the display device. The synthesized CFP will play a crucial role in visualizing the LFPs on various materials surface, organic light emitting diodes (OLEDs) and anti-counterfeiting applications

Структурні, оптичні та електричні властивості легованих Ce наночастинок SnO2, підготовлених методом горіння гелю з додаванням поверхнево-активних речовин

Нанокристалічні чисті та леговані Ce порошки оксиду олова (SnO2) синтезували методом горіння гелю з додаванням поверхнево-активних речовин (CTAB і PEG), використовуючи сечовину як паливо. Підготовлені зразки характеризували PXRD, FESEM, UV-Vis, FTIR та імпедансним аналізатором. Аналіз PXRD виявив тетрагональну рутильну фазу SnO2. Розмір зерна оцінювали за допомогою рівняння Дебая-Шеррера та методу Вільямсона-Холла. Параметри елементарної комірки були знайдені за допомогою уточнення Рітвельда та графіка Нельсона-Ріллі. На фотографіях FESEM було показано утворення наночастинок майже сферичної форми. Спектр FTIR виявив смуги завдяки фундаментальним гармонікам та комбінації з'єднань Sn-O та Sn-O-Sn. У спектрах UV-Vis показано зменшення ширини забороненої зони із вмістом Ce внаслідок збільшення дефектів. Вплив легування Ce на електричні властивості вивчали при кімнатній температурі. Діелектричні параметри ε' і tanδ були максимальними для зразка чистого SnO2. Варіювання діелектричних властивостей та змінної провідності з частотою зумовлено міжфазною поляризацією типу Максвелла-Вагнера.Nanocrystalline pure and Ce doped tin oxide (SnO2) powders were synthesized through surfactant (CTAB and PEG) assisted gel combustion method using urea as a fuel. Prepared samples were characterized by PXRD, FESEM, UV-Vis, FTIR and Impedance analyzer. The PXRD analysis revealed the tetragonal rutile SnO2 phase. The grain size was estimated using the Debye-Scherrer equation and Williamson-Hall method. The cell parameters were found using Rietveld refinement and Nelson-Rieley plot method. The FESEM pictures showed the formation of nanoparticles of almost spherical shape. FTIR spectrum revealed the bands due to the fundamental overtones and combination of Sn-O and Sn-O-Sn entities. The UV-Vis spectra showed the decrease in band gap with Ce content due to an increase in defects. The effect of Ce doping on the electrical properties was studied at room temperature. The dielectric parameters, ε' and tanδ were maximum for pure SnO2 sample. The variation of dielectric properties and ac conductivity with frequency is due to the Maxwell-Wagner type of interfacial polarization