Research on the modification effect of various high-energy particles of oxygen plasma on the surface of bamboo charcoal:
Since the 1960s, plasma technology is a new discipline developed on the basis of the interdisciplinary basis of physics, chemistry, electronics, and vacuum technology. In recent years, the application of plasma technology in the fields of material science, medicine and biology, environmental science, metallurgy, chemical industry, light industry and textile has been very active. Among them, the application of material surface modification is particularly extensive. Since the plasma contains a large number of high-energy particles such as free electrons, ions and metastable particles, the energy of these particles is significantly higher than the bond energy of common chemical bonds on the surface of general materials including carbon materials. Various high-energy particles have the ability to break old chemical bonds on the surface of carbon materials and form new bonds, thereby endowing the material surface with new physical and chemical properties.
Using suitable working conditions to modify carbon materials can significantly change the surface physical and chemical properties of carbon materials, thereby enhancing the adsorption performance of carbon materials for specific pollutants in the environment. Due to the small particle size of bamboo charcoal particles (75~150μum), bamboo charcoal particles with a sponge-like structure have a large number of pore structures on the surface. These pores are mainly formed by vascular bundles, parenchyma cells and vessels on bamboo. During the carbonization process, the organic components inside these pores are fully volatilized at high temperature, and the remaining pores become the main pore structure on the surface of bamboo charcoal. There are a large number of cracks and folds on the surface of bamboo charcoal particles, which together with the pores on the surface form a complex pore structure on the inner surface of bamboo charcoal.
The surface morphology of bamboo charcoal did not change significantly, indicating that oxygen plasma modification had little effect on the surface morphology of bamboo charcoal. Under the condition of oxygen plasma modification, the surface of bamboo charcoal did not react to form new groups, but some existing group types may be generated, which increased the group density.
In the process of oxygen plasma modification, the pore performance of bamboo charcoal can be effectively improved through reasonable control of working conditions. The reasons can be attributed to the following two points:

1. Etching, within a suitable modification time range, the plasma can fully etch the inner and outer surfaces of the bamboo charcoal, causing new undulations and roughness on the inner and outer surfaces of the bamboo charcoal, forming many potholes and increasing the specific surface area.
2. Group generation, within a suitable modification time range, the plasma can react with specific points on the inner and outer surfaces of bamboo charcoal to generate a large number of new oxygen-containing groups. The accumulation of these oxygen-containing groups inside the pores will cause Significantly reducing the pore size at this position has positive significance for the increase of the specific surface area of bamboo charcoal.
Overall, there is a suitable modification time range for the modification of bamboo charcoal by oxygen plasma. Within this range, etching and group generation can synergistically improve the pore structure of bamboo charcoal. Once the modification time is too long, , it will cause excessive etching and excessive generation of groups inside the bamboo charcoal, and damage the original pore structure of the bamboo charcoal. The surface modification effect of oxygen plasma on bamboo charcoal can significantly improve and enhance the physical and chemical properties of the surface of bamboo charcoal, and increase the specific surface area, total pore volume, and micropore volume of bamboo charcoal by reasonably regulating the working conditions of oxygen plasma. and microporous surface area, while also increasing the number of oxygen-containing groups on the surface of bamboo charcoal.
Since parameters such as the specific surface area and pore volume of carbon materials are the key factors in determining the adsorption performance, the type and number of oxygen-containing groups on the surface of carbon materials also play a very important role in the process of adsorbing organic compounds and heavy metals in environmental media . The oxygen plasma modified bamboo charcoal has obvious improvement and improvement in the above two aspects, and can have better adsorption performance, thereby expanding the application scope of bamboo charcoal in the field of environmental pollutant adsorption.