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The mesoporous MnSBA-15 materials with different [n.sub.Si]/[n.sub.Mn] ratios f 4, 8, 20, and 50 are synthesized for the first time, using manganese nitrate tetrahydrate and Pluronic 123 triblock polymer [(EO)20(PO)70-(EO)20]. With increasing synthesis temperature, an increase the unit cell parameter, pore size, and pore volume and a decrease the specific surface area and pore wall thickness of MnSBA-15 could be obviously noted by the results of XRD and N2 adsorption.

The avant-garde supercapatteries have received substantial curiosity for their noteworthy electrochemical performance. Devising battery-type substances with appreciable electrocapacitive accomplishment and high electrical transmittance is imperative to boost the energy stowing knack of supercapattery devices. A pure CoWO4 nanostructure and a composite of CoWO4 incorporating r-GO were prepared by hydrothermal method. The XRD and FTIR results validated the effective development of high-quality CoWO4 and r-GO. FESEM images reveal a nanosphere-like architecture of CoWO4 over r-GO sheets. The pure and composite nanomaterials show good battery-like traits in electrochemical studies. The CoWO4/r-GO electrode exhibits better electrochemical activity compared to pure sample. The specific capacitance (and specific charge capacity) calculated at a current density of 2 A g−1 for CWO/r-GO and CWO is 382.7 A g−1 (158.1 C g−1) and 262.7 A g−1 (105.1 C g−1), respectively. The results obtained herein evince that the developed nanocomposite is a propitious electrode candidate for supercapattery. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis of three-dimensional (3D) and one-dimensional (1D) hierarchical hematite (α-Fe2O3) nanostructures on fluorine-doped tin oxide (FTO) glass substrate by hydrothermal and hybrid microwave annealing (HMA) process for photoelectrochemical (PEC) water oxidation. The properties of prepared α-Fe2O3 nanostructures were characterized by different characterization techniques. Moreover, the PEC water oxidation performance of the α-Fe2O3 nanostructures was studied under simulated solar irradiation. The 3D α-Fe2O3 nanostructures shown an enhanced photocurrent density of 0.48 mAcm−2 at 1.23 V vs. RHE when compared with 1D α-Fe2O3 nanostructure (0.07 mAcm−2 at 1.23 V vs. RHE) under 100 m Wcm−2 solar irradiation. This result demonstrates that the 3D α-Fe2O3 nanostructures have higher PEC water oxidation ability than 1D α-Fe2O3 nanostructure. The enhancement in the PEC water oxidation process was due to the higher electrical conductivity with suppressed charge recombination rates. [ABSTRACT FROM AUTHOR]

ZSM-5:CeO2 nanocomposites were prepared by two-step hydrothermal method in combination with the wet impregnation method. The synthesized nanocomposites were characterized by XRD, FESEM, TEM, EDX, elemental mapping, FTIR and UV–vis analysis. The bandgap investigations were done using tauc plot and the bandgap of ZSM-5 has been reduced from 3.90 to 3.15 eV upon CeO2 loading. The synthesized nanocomposites were tested for photocatalytic activity under a halogen lamp and the effect of CeO2 loading on ZSM5 has been examined. Among the various nanocomposites synthesized, ZSM-5:CeO2 25 wt% exhibited better methyl orange degradation of about 95.6% with an initial dye concentration of 10 mg/l, pH 7, 100 mg of photocatalyst under halogen lamp for 75 min. Additionally, the effect of various reaction parameters like dye concentration (10–25 mg/l), photocatalyst dosage (25–125 mg), and pH (3–9) was probed to get better performance. Tapping experiments were conducted with various radical scavengers to get insight into the key active species responsible for the photodegradation of methyl orange. The result portrays the importance of hydroxyl radical for the degradation of methyl orange dye. Cycle test and stability studies showed that the photocatalyst was stable even after four cycles. In summary, ZSM-5:CeO2 nanocomposites can be a suitable photocatalyst for numerous applications in the field of photodegradation of organic contaminants. [ABSTRACT FROM AUTHOR]

Bismuth sulfide (Bi2S3) nanorods have been prepared using a simple and low-cost reflux method. This method is easy to handle and opens up a way to manufacture photocatalytic pigment at a low cost. The Bi2S3 catalyst was subjected to X-ray diffraction (XRD), UV–Visible spectroscopy (UV–Vis), scanning electron microscope, high-resolution transmission electron microscopy, FT-IR spectroscopy, thermogravimetric analysis (TG/DTA), and X-ray photoelectron spectroscopy. The structures of the Bi2S3 nanorod have been investigated and were seen to be orthorhombic. The electron microscopic observations showed that surfactants greatly affect the morphologies of the as-prepared Bi2S3 samples. The XRD and TEM results confirmed that the Bi2S3 nanorods have a high surface area and are good crystallinity. TEM measurements revealed that the average breadth and length is 75 nm and 385 nm for Bi2S3 nanorods prepared using NaOH. The uniform one-dimensional Bi2S3 nanorods are due to the presence of NaOH which controls the nucleation and growth process of Bi2S3 nanorods. The photocatalytic activity of the Bi2S3 nanocrystallites has been estimated by the degradation of methylene blue (MB) under the irradiation of halogen light. It was noted that the absorption peak corresponding to MB reduced indicating the photocatalytic nature of the sample. In these conditions, the maximum degradation of the dye was achieved within 140 min for KOH added Bi2S3 samples and the photodegradation efficiency is 87.98%. A possible photocatalytic reaction mechanism of the Bi2S3 samples has also been proposed. [ABSTRACT FROM AUTHOR]

The development of efficient, scalable, and economically viable electrode materials with high specific capacitance is of great significance for supercapacitor applications. Herein, α-Fe2O3 nanoparticles, α-Fe2O3/rGO, and α-Fe2O3/SnO2/rGO nanocomposite were synthesized by a one-step hydrothermal method. Different characterization techniques were used to study the physical and chemical properties of the prepared materials. The powder XRD measurement revealed that the formation of the ternary composite without any impurities. As characterized by SEM and TEM techniques, both α-Fe2O3 and SnO2 nanoparticles were embedded on two-dimensional reduced graphene oxide sheets. The electrochemical properties of the prepared electrode materials were studied by cyclic voltammetry and galvanostatic charge/discharge, and impedance spectroscopy techniques in a 6 M KOH electrolyte solution. All the electrode materials exhibit Faradic reaction peaks in CV curves which imply the pseudocapacitive nature of the prepared materials. The ternary α-Fe2O3/SnO2/rGO nanocomposite demonstrated the enhanced specific capacitance of 821 Fg−1 at 1Ag−1 than that of α-Fe2O3 nanoparticles (373 Fg−1 at 1Ag−1), and α-Fe2O3/rGO (517 Fg−1 at 1Ag−1) nanocomposite with excellent cyclic retention (98.7%) after successive 10,000 cycles. This improved electrochemical performance of ternary α-Fe2O3/SnO2/rGOnanocomposite is mainly attributed to the surface properties of nanostructures of metal oxides and an excellent conductive network. Moreover, the asymmetric supercapacitor (ASC) device was fabricated using the ternary α-Fe2O3/SnO2/rGOnanocomposite as the anode material and rGO as the cathode material. The ASC device showed an energy density of 17 Wh Kg−1 at a power density of 3585 W kg−1 and retains 94.52% capacitance after successive 5000 cycles at a current density of 10Ag−1. [ABSTRACT FROM AUTHOR]

Low power is an essential requirement for suitable multimedia devices, image compression techniques utilizing several signal processing architectures and algorithms. In numerous multimedia applications, human beings are able to congregate practical information from somewhat erroneous outputs. Therefore, exact outputs are not necessary to produce. In digital signal processing system, adders play a vital role as an arithmetic module in fixing the power and area utilization of the system. The trade-off parameters such as area, time and power utilization and also the fault tolerance environment of few applications have been employed as a base for the adverse development and use of approximate adders. In this paper, various types of existing adders and approximate adders are analyzed based on the area, delay and power consumption. Also, an approximate, high speed and power efficient adder is proposed, which yields better performance than that of the existing adders. It can be used in various image processing applications and data mining, where the accurate outputs are not needed. The existing and proposed approximate adders are simulated by using Xilinx ISE for time and area utilization. Power simulation has been done by using Microwind Software. [ABSTRACT FROM AUTHOR]