EFFECT OF CRYOGENIC TREATMENT ON ALUMINA NANOPOROUS MATERIAL

Vishal Sharma, Sunita Mishra

Abstract: Alumina is one of the important ceramic material having high melting point, thermal conductivity , hardness etc. Their demand in nanodimension is very high due to wider application in the field of electronics, optoelectronics , mechanical and reinforcement composites etc. Alpha phase alumina is highly stable ceramic material, that undergoes agglomeration when treated at higher temperature ( > 8000 Celsius ) during synthesis process .In present work successful effort was made to minimize agglomeration besides forming stable 1-D Nanorod alpha ( a) phase alumina structures by cryogenic treatment . The experimentation starts with the formation of alumina by sol –gel synthesis route while dissolving aluminium chloride hexahydrate ( AlCl3 .6H2O ) into aqueous hydrochloric acid ( HCl ) . Thereafter it was subjected to mechanical grinding and calcination at 10500 Celsius for 6-7 hours . The repetition of whole process of grinding and calcinations for 8-10 times , gave alpha (a) phase nanoporous alumina in agglomerated state . After that it was given bath in cryogenic Liquid Nitrogen ( -1960 Celsius ) for 6-7 hours and left at normal temperature for 3-4 hours before further processing . Their characterization study were done using BET ( BEL belsorp ) , XRD( Panalytical.s X.Pert Pro ) and FE SEM ( SU8010 ) . BET shows the formation of porous alumina structure with mean diameter 26.126 nm , whereas the formation of alpha (a) phase crystalline alumina was confirmed by XRD and lastly formation of highly stable 1-D Nanorods were confirmed by FE- SEM images.

Keywords: CRYOGENIC TREATMENT

DOI: https://doi.org/10.15623/ijret.2017.0613001