Uniform and ordered periodic mesoporous organosilica thin films by a facile solution growth approach

We demonstrate a novel solution growth method for synthesis of uniform and ordered periodic mesoporous organosilica (PMO) thin films on substrate. The approach is simple and facile, in which a substrate is immersed into a solution containing 1,2-bis(triethoxysilyl)ethane (BTSE) precursor, cetyltrimethylammonium bromide (CTAB) surfactant template, ammonia catalyst, ethanol, and decane. The precursors are hydrolyzed, cross-linked by ammonia catalyst, and assembled with the surfactant on the substrate to form highly ordered hexagonal mesostructures. The obtained mesoporous silica films possess substrate-size-dependent dimension, uniform and tunable thickness (30–100 nm), and ethane group incorporated frameworks. The obtained PMO films have been characterized by field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and grazing incidence small-angle X-ray scattering (GISAXS). The film thickness can be easily controlled by adjusting the reaction temperature. A formation mechanism of the ethane-bridged PMO films via CTAB directed sol–gel process is further proposed.