Ionic liquid template assisted synthesis of porous nano-silica nails

Abstract

Our planned strategy to obtain porous materials was to synthesize porous silica at a fast gelation rate which can be attained by using non-hydrolytic sol-gel route with high ionic liquid (IL)-loading. Then the silica might get drawn into a tubular spring-like structure that would cage the ionic liquid within its fold and some ionic liquid might get into the pores of the silica spring. To test this strategy, we used a mixture of tetra methyl ortho-silane and ionic liquid in such a ratio that the resulting product, SiO2 : IL, has a content of IL as high as 85-92 wt%. Interestingly, the experimental results described in this paper have proved the validity of our strategy to obtain "porous" nano-silica particles (sometimes, "porous nail" structures also resulted).