It depends on the procedure by which a mesoporous silica is prepared. If it is done using suitable templates, pores pass  throughout  the silica. Look, e.g., at papers of Wieslaw Rott, father of mesoporous sieves.

Best regards, J.V.

Dear Georgios,

look for the papers of mcm 41 synthesis and characterization.

I dont know, why you want to know? is it for doping, grafting or some other purpose?

simply consider a pencil with a carbon in the center of wood out side, and there are many pencils set together, now think about that bunch without carbon inside, when you we characterize material using SEM or TEM, it shows the porous morphology of the surface, when the accelerated electrons blocked/reflected/refracted by the material it shows dark line/solid part of the material.

I hope this would give you more idea to think about porous materials.

note: not all the materials behave in the similar way.

http://pubs.acs.org/doi/abs/10.1021/cm060265y

http://pubs.acs.org/doi/abs/10.1021/cm050960q 

Dear all

Thanks for your responses. What i was trying to find is nothing new and i found out that it's called hollow mesoporous silica. I will read through your articles cause they can only be beneficial.

Cheers all

Template mediated synthesized mesoporous material has perfect pores from one end to other. What you mean by mesoporous silica? Go through the articles refereed by others also.