Exploration on Tungsten Trioxide Nanorods Growth Principle

Nanorod is a scale from a few nanometers to hundreds of nanometers rod-like nanoparticles. The surface plasmon resonance wavelength of Nanorods with the aspect ratio can be changed from the visible (550 nm) to near infrared (1550 nm). Nanorod is continuously adjustable, high, and the surface of electric field can high to 10e7 times, which can make a great optical absorption. In scattering cross section, as well as light and heat from 50% to 100%, this performs an adjustable efficiency. Molecular biological properties of nanorods in materials science community being strong concern and caused many materials scientists, biochemists, physicians, physicists, micro electronic engineers and other scientists to the extensive and in-depth research because it is optical, photovoltaic, solar thermal, photochemical.

In the synthesis process, the selection of the sodium salt as a directing agent can be synthesized nanorods tungsten trioxide, and sulfates as a director are not the product of rod-shaped morphology, which can be inferred sodium ions in the rod formation process, and it plays a decisive role. When the molar ratio of sodium sulfate and sodium tungstate is 4: 1, the product can be seen in XRD diagrams of the various hydrothermal time, when the hot water is heating for longer than 24h, the product is pure hexagonal tungsten trioxide, when the hexagonal tungsten trioxide (200 planes) has emerged, hydrothermal time is 6h, and the (001) plane appears to 12h, which indicates the beginning of the tungsten trioxide hexagonal crystal growth (200) crystal surface is an advantage, (200) have more chance of sodium ion adsorption solution, reducing the chance of tungsten trioxide crystals of (200) plane growth. Making tungsten trioxide another advantage to its crystal face (001) growth, along with the hot water time, the (001) plane growth significantly, tungsten trioxide nanorods can be obtained by hydrothermal after 48h.