Study On Preparation Of Nano ZnO Using Cellulose Whisker As Template

Mercerized cotton fibres are used as the raw materials to optimize the preparation process of the cellulose nanofibers. Using the low concentration mixed acid hydrolysis method to prepare nano cellulose whisker template. Then the precipitate- sinter method and the aquiculture-pyrolysis method are adopted to prepare porous Nano-ZnO with the appearance of cellulose nanofibers.The structural characterization of cellulose nanofibers is checked by field emission scanning electron microscopy(FESEM) and fourier transformation infrared spectroscopy(FTIR),based on which the paper elaborates on the influence of the Hydrolysis mechanism and preparation conditions towards the appearance of the cellulose nanofibers. Then the structural characterization of Nano-ZnO is characterized by FESEM and X-ray diffraction(XRD), according to which the paper thus discusses the differences of the appearance when different preparation methods and conditions are used.The result of the experiment shows that: cotton fibers swell from the inside of the lumen in mercerzed alkali solution and no new chemical bonds are formed, but allomorph cellulose changes. Cellulose nanofibers made with low concentration acid hydrolysis enjoys a high stability in crystalline region stability compared with that prepared in high-concentration acid hydrolysis conditions. The whisker’s porous network structure is due to the interaction of the hydrolysis in the amorphous region and hydrogen bonding nano whisker. In the hydrolysis,only-OH is formed, and other chemical bonds remain the same. In the hydrolysis process of precipitate-sinter, the concentration rate of zinc ion has remarkable influence on the final appearance. When the concentration rate of zinc ion is 0.4mol/L, the micro morphology of the products is most similar to the template with the obvious porous effect. In the process of aquiculture-pyrolysis, mesoporous Nano-ZnO with uniform particle size and same structure with template can be collected if 3% Zn(CH3COO)2 is reacted under 600℃.At last, the paper conducts gas-sensing property tests for both of the two products, and the result shows that both of the two methods can make high ethanol gas sensing products while the sensitivity of the product made under aquiculture-pyrolysis is more prominent.