| Compared with traditional carbon material, spherical carbonous materials with specific advantages, due to its unique geometrical structure, have good shape, smooth outer surface, monodispersed size and high dentisity, which were used in the areas of electronic, adsorbent, catalyst, chemical protection and so on.This synthesis was focused on the preparation of carbon sphere in a glucose hydrothermal treatment. The experimental conditions (hydrothermal temperature, reaction time, glucose concentration and a second treatment) were investigated, which play the key role in the shape and chemical structural control. Scanning electron microscopy (SEM), elemental C/H/O chemical analysis, Fourier transform diffuse reflectance infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) were applied in identifying its shapes, sizes and functional groups. It can be noted that, carbon spheres with smooth outer surface, tunable and monodispersed size and perfect spherical shape were prepared in 300-1200 nm. With the increasing temperature, its diameter increase obviously, however, its morphology and monidisperity changed without a simple tendency. The reaction time plays an important role in shape-control, but has few relationships with its diameter. Extending feeding time, CS with irregular shapes (such as peanut shape, liner strucutre) appears, due to the fusion. Higher glucose concentration is available to the formation of larger spheres with good morphology. CS is consisted of C, H and O, a higher oxygen content in the core. The ratios of O/C are about 35%, indicating large numbers of functional groups in CS. The number of functional groups (mainly -OH and C=O) on the outer surface were determined by experimental factors.The possible mechanism of CS may maintain two steps, which were "nucleation" and "growth of nuclea". A second hydrothermal treatment separating the process of "nucleation" and "the growth process" effectively is helpful to prepare a larger CS with smooth outer surface, prefect spherical morphology and a narrow size distribution. The process was named as "aging".The maximum adsorption capacity of CS to Pb2+ was 2.4 mmol/g, which is bigger than other traditional adsorbent materials. The higher adsorption resulted from ionic bonds or covalent bonds between oxygen-containing groups on the surface and Pb2+.Porous carbon spheres (PCS) were prepared by KOH activation. Two different methods were applied to mix KOH and CS, which were mechanical mixing and immersion method. It resulted that PCS has irregular morphologies and various sizes following the mechanical mixing, which suggested the process of mechanical mixing is unsuitable to PCS. PCS prepared after a process of immersion were discussed. CS activated at 350℃for 30 min under nitrogen enviroment were more suitable to the preparation of PCS than CS. PCS with perfect spherical structure, smooth outer-surface, small size and a narrow distribution were prepared at 700℃for 60 min under nitrogen enviroment, its BET surface areas 967.19 m2/g, pore volumes 0.453 cm3/g, whereas the ratio of micropores volume is 88.3%. The Process of KOH activation includes "gasification" and "activation".
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