Preparation Of C-ZnO Composite By Lignin And The Study On Its Photocatalytic Property

As a "green technique" used to decompose organic pollutants, photocatalysis has a highly efficiency and broad applicability with the intensification of environmental pollution, zinc oxide (ZnO) is one of these semiconductor photocatalytic materials which have outstanding properties. Carbon materials usually have a high specific surface area and abundant pore structure, which are often used as catalyst or the carrier. Thus, the preparation of high-efficient and cheap photocatalystic composite through the combination of ZnO and carbon is in great significance.In our work, lignosulfonate which is produced by the pulp and paper industry was utilized. A simple direct precipitation method was used to prepare C-ZnO composites. Sodium lignosulphonate was used as surfactant and carbon sources, then the C-ZnO composites were obtained in mixed solvents of ethylene glycol and water. The components and structure of the composite were characterized by XRD, Raman and XPS analysis, which have indicated that the composites consist of ZnO and carbon. The influences of different addition amounts of sodium lignosulphonate, calcination temperature and pH of reaction solution on structures and crystal forms of C-ZnO composites were investigated. The results show that the structure of the substrate composed of carbon in which ZnO rods grew. Meanwhile, the experiments on the photocatalytic property were also carried out by obtained C-ZnO composites. Owing to the unique structure, our C-ZnO can absorb the organic pollutants on the surface and degraded it at the same time. Since the absorpation and photodegradation are simultaneously carried on, it resulted in the improvement of photocatalytic efficiency by the synergistic effects. Besides, the influence factors on C-ZnO photocatalytic property, such as addition amount of sodium lignosulphonate, were also discussed to obtain the optimal condition.