Papers by Author: Tian Jian Lu

Abstract: A hierarchical porous carbon derived from phenolic resin (PF) was processed using ethylene glycol (EG) and starch as double porogens. The influences of composition of starting mixture, including the two porogens and PF, on morphological properties and microstructure of the porous carbon were investigated. It was demonstrated that the content of starch and the relative content of EG to PF played key roles in determining the number, size and formation of the hierarchical pores, which in turn led to changes in the properties and the microstructure of the porous carbon. In particular, the number of the first-level pores (diameter ~10–40 μm) increased with the content of starch increasing, and the high relative content of EG to PF contributed to the formation of the second-level pores (diameter ~0.5–2 μm), which were closely related to the formation mechanisms of the two-level pores, respectively. Under the present experimental conditions, sufficiently high starch content can result in the microstructural abnormalities, such as the incomplete decomposition of starch and the formation of the third-level pores which originated from the stack of discrete carbon particles.

Abstract: In this research, the metal and ceramic laminates Ti/Al2O3, Ni/Al2O3 were prepared by PAS. The bonding interfaces of Ti/Al2O3, Ni/Al2O3 were observed and analyzed. The microstructures of laminates were observed by SEM. It was shown that the joints of the samples were tight and had not visible flaws. Moreover, the comparison of Ti/Al2O3 and Ni/Al2O3 laminates showed that the join mechanisms of them were different. Ni/Al2O3 laminates that had not apparent conversion zone were joined by diffusion and had lower bond strength. Ti/Al2O3 laminates have obvious conversion zone because Ti and oxygen have strong combining power. Three-point bending test indicated that the fracture of laminates was correlated to the bond strength of the interface.

Abstract: We used ethylene glycol as pore-forming agent to prepare porous carbon with interconnected pores derived from phenol–formaldehyde resin. The mixture of resins and glycol was by polymerization and pyrolysis monolithic material of porous carbon with interconnected mesopores and a narrow pore size range. The average pore size of the porous carbon obtained was 28.2 nm. The nitrogen adsorption isotherm for the porous carbon exhibited type IV isotherm, which corresponded to mesoporous adsorption. The method could endow porous carbon with BET surface area and pore volume about 500 m2/g and 0.607 cm3/g, respectively. The mesopores in porous carbon formed as a result of phase separation of resin-rich phase and glycol-rich phase at polymerization and remove of glycol-rich at subsequent pyrolysis.