Synthesis and Physical Properties of Co₃O₄ Nanowires

Abstract

By carefully controlling the reacting time, temperature, and humidity, we have prepared Co 3 O 4 nanowires by heating a pure cobalt foil in atmosphere. Scanning electronic microscopy demonstrates that the nanowires have a diameter ranging from 20 to 100 nm and their typical lengths are in the range of 10-20 µm. X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectrum, and transmission electronic microscopy analyses demonstrate that the nanowires are Co 3 O 4 . The optical property of the nanowires is determined by photoluminescence spectrum. The magnetic behavior of it is investigated by a magnetic property measurement system. The nanowires exhibit some novel optical and magnetic properties, which are different from its bulk material.

Synthesis of Co3O4/Poly(N‐vinylcarbazole) Core/Shell Composite With Enhanced Optical Property

“…[15][16][17] Experimental Part Materials Co 3 O 4 nanoparticles used in this study were synthesized in our laboratory by well-known published method. [11] The formation of Co 3 O 4 nanoparticles was confirmed by the transmission electron microscopy (TEM) observation ( Figure 1a) and from the electron dispersed X-ray (EDS) spectrum ( Figure 1b). NVC monomer used in this study was purchased from Sigma-Aldrich Chemicals and was recrystallized from hexane and stored in a dark place.…”

“…[10] On this context, some novel methods for the synthesis of Co 3 O 4 nanoparticles have recently been explored. [11] However, the Co 3 O 4 nanoparticles are very sensitive to air and moisture, which degrades the ultimate performance of nanodevices. One of the best options would be poly(Nvinylcarbazole) (PNVC) coating to protect Co 3 O 4 nanoparticles from aerial oxidation and corrosion, giving good performance for a long time.…”

Magnetic colloid by PLA: Optical, magnetic and thermal transport properties

“…9b. A PL spectrum reveals three emission peaks at ∼328, ∼378 and ∼526 nm, which lie in violet/blue [27][28][29]. The PL spectrum has been clarified with the help of energy band diagram.…”

“…If the temperature increases the root mean square velocity increases and hence Brownian motion of dispersed NPs increases in base liquid, this increases the thermal conductivity of nanofluids [27]. On the other hand on increasing amount of NPs in base liquid this also increases Brownian motion and hence enhances thermal conductivity of nanofluids.…”

Tuning the Morphology of Metal Oxides for Catalytic Applications

“…104 Besides chemical routes in liquid solution, physical techniques and hard-templating methods, such as template directing and electrospinning, have been applied to prepare one-dimensional Co 3 O 4 nanostructures. [105][106][107][108][109][110][111][112][113][114][115][116] Co 3 O 4 nanowires/nanorods can be accomplished by growing on solid substrates, typically involving the reaction of gaseous oxygen molecules with cobalt foil. 105-108 A solution-based route has been developed for the direct growth of freestanding hollow Co 3 O 4 nanowire arrays on a variety of substrates, such as transparent conducting glass, Si wafer, Cu or Ti foil, and polystyrene substrate.…”