Self-Assembled NiWO₄ Nanoparticles into Chain-like Aggregates on DNA Scaffold with Pronounced Catalytic and Supercapacitor Activities

Abstract

The chain-like NiWO 4 nanomaterials on DNA scaffold were characterized using several spectroscopic techniques. The UV-Visible (UV-Vis) absorption spectra were recorded in a double beam spectrophotometer purchased from Unico (model 4802 UV-Vis spectrophotometer). The transmission electron microscopy (TEM) analysis was done with a Tecnai model TEM instrument (TecnaiTM G2 F20, FEI) with an accelerating voltage of 200 KV. The Field Emission Scanning Electron Microscopy (FE-SEM) analysis was recorded with Zeiss ultra FE-SEM instruments. The Energy Dispersive X-ray Spectroscopy (EDS) analysis was done with the same FE-SEM instrument with a separate EDS detector (INCA) connected to that instrument. The X-ray diffraction (XRD) analysis was done using a PAN analytical Advanced Bragg-Brentano X-ray powder diffractometer (XRD) with Cu Kα radiation (λ = 0.154 nm) with a scanning rate of 0.020 s -1 in the 2θ range 10-90°. The X-ray photoelectron spectroscopic (XPS) analysis was done to check the chemical composition and the state of elements present in the outermost part of materials and analyzed by using Theta Probe AR-XPS System, Thermo Fisher Scientific (U.K). The LASER Raman measurements were carried out with Renishaw inVia Raman Microscope using an excitation wavelength of 632.8 nm (He-Ne laser). The excitation light intensity in front of the objective was ~10 mW with a spectral collection time of 1 sec for Raman experiment. The integration time for our measurement was set to 10 sec. The photoluminescence (PL) study was done with Varian

Synchrotron-based far-infrared spectroscopy of nickel tungstate

“…Recent interests on NiWO 4 have been stimulated by its applications as a catalyst [9,10], in supercapacitors [10,11] and light-controlled bipolar resistive switching devices [12] as well as by numerous possibilities to produce it in nanostructured form [13][14][15][16][17][18][19][20].…”

Bio‐Nanotechnology in High‐Performance Supercapacitors

“…The addition amount of bio-macromolecule as the bio-templates should be controlled within the low range to guarantee the conductivity of electrode materials is not influenced, while most of the bio-polymers can be removed through pyrolysis process during the synthesis of inorganic materials, such as Nb 2 O 5 , [125] ZnWO 4 , [126] NiWO 4 . [127] In this section, we will primarily focus on the use of bio-macromolecule templates to fabricate 1D SC electrode materials. PANI nanowires were prepared by electrodeposition using starch as bio-template with OH groups on its chain to form hydrogen bonds with aniline (AN), [91g] and the as-prepared nanowire electrodes had a high C sp (882 F g −1 ) at the current density of 7 A g −1 but showed only 5% capacity loss after 500 cycles.…”

“…DNA has distinct advantages as a bio-template for building novel nanomaterials due to its miniature scale and well-ordered geometric structure, as well as its distinctive molecular recognition capacity. [135] DNA as a bio-template has recently been widely studied to synthesize metal oxide [125][126][127] and polymer [136] based SC electrode materials. Metal oxide nanoparticles can be made to aggregate together in a chain-like morphology by dissolving the inorganic salt in DNA aqueous solution, and the size of individual nanoparticles as well as the chain diameter can be tuned through the reaction parameters (concentration ratio of starting precursor solution, reaction time, etc.…”

Highly flexible conductive fabrics with hierarchically nanostructured amorphous nickel tungsten tetraoxide for enhanced electrochemical energy storage

“…Cobalt tungsten tetraoxide (CoWO 4 ) and nickel tungsten tetraoxide (NiWO 4 ) are important inorganic functional materials for diverse potential applications [48][49][50]. Additionally, these materials offer excellent electrochemical properties as pseudocapacitive materials in energy storage devices, which can be ascribed to their good reversible Faradic redox reactions and good conductivity on the order of 10 -7 to 10 -3 S/cm by the incorporation of W atoms.…”