Pore size tuning of sol-gel-derived triethoxysilane (TRIES) membranes for gas separation

摘要: Abstract Triethoxysilane (TRIES), which consists of three ethoxy groups and a Si-H bond as pendant-type alkoxysilane, was utilized Si precursor for the fabrication gas separation membrane. The effect membrane parameters such sol preparation conditions calcination temperatures on network structures evaluated. degree dehydrogenation in aqueous solution independent H 2 O/Si molar ratio sol, but hydrolysis polymerization (-OEt) depended O ratio. TRIES membranes calcined at 550 °C under N showed decrease size with an increase sol. TRIES-derived pore also temperature, decreased lower temperatures. For example, high selectivity He/N /N approximately 1000 600, respectively, however, case 300 °C, Knudsen diffusion dominated small molecules (H selectivity: 4.3) molecular sieving favored large /CF 4 : >100, /SF 6 >400). When fabricated by most were still present networks, estimated 0.577 nm, larger than that tetraethoxysilane (TEOS) 350 °C (0.426 nm). On other hand, when TEOS 550 °C, both same (TEOS: 0.385 nm, TRIES: 0.382 nm), due to formation Si-OH well forming Si–O–Si bond.