Periodic mesoporous organosilicas, PMO

Hoffmann, F. Cornelius, M. Morell, J. Froba, M. 2006. Periodic mesoporous organosilicas (PMOs) Past, present, and future. J. Nanosc. Nanotech. 6 265-288. 

W. J. Hunks and G. A. Ozin, Challenges and advances in the chemistry of periodic mesoporous organosilicas (PMOs), J. Mater. Chem., 2005, 15, 3716. 

MULTI-SILYLATED COMPOUNDS FOR THE SYNTHESIS OF (PERIODIC) MESOPOROUS ORGANOSILICAS (PMOs) 72... 

Single-Source Precursor Method Using Bis- and Multi-Silylated Compounds for the Synthesis of (Periodic) Mesoporous Organosilicas (PMOs)... 

Hybrid Silica Materials Use of silica with periodically mesoporous organosilicas (PMOs) morphology, with organic groups as functionalization materials, for applications in sensing. 

Ordered inorganic-organic hybrid silica-based composites include the following [48] (1) as-made (uncalcined or unextracted) surfactant-silica mesophase, (2) surface-modified mesoporous silica, (3) periodic mesoporous organosilica (PMO), (4) organic-containing mesoporous Si02-... 

F. Hoffmann, M. Cornelius, J. Morell, and M. Froba, Periodic Mesoporous Organosilicas (PMOs) Past, Present, and Future. J. Nanosci. Nanotechnol., 2006, 6, 265-288. 

Many of the non-silica compositions showed problems with the stability and quality of the structure. Efforts to address these issues have been on going and quite successful in some cases such as all-alumina compositions (see below). Silica-based materials remain dominant as the most versatile and best quality molecular sieves (structure and stability) available by a facile synthesis. These attributes, especially the convenient synthesis made mesoporous silicate attractive for post-synthesis functionalization with other elements as well as organic moieties with active groups/ccnters. Recently the compositional diversity has been extended further to include both silica and organic moieties within the framework. The new class is referred to as periodic mesoporous organosilicas (PMOs). The synthesis involves surfactant-assisted assembly by hydrolysis of organo-silicon compounds. Additional discussion of the PMOs is presented below. 

Our studies also demonstrated the thermally induced pore closure for ordered organosilicas with organic groups in the framework (which are referred to as periodic mesoporous organosilicas, PMOs PMOs are particularly interesting as low-... 

Mixed micelles can be exploited as templates for preparation of nanoporous materials. Oligomeric alkyl-ethylene oxide surfactant (Polyoxyethylene (2) cetyl ether, B52), and ionic surfactant (cetyltrimethylammonium bromide, CTAB) form mixed micelles that self-assemble into well-ordered hexagonal and bimodal mesostructures. These systems can be used as templates to synthesize hydrothermally stable organized periodic mesoporous organosilicas (PMOs). The X-ray diffraction (XRD), TEM, BET, NMR and hydrothermal studies have been used to investigate the effects of B52 on the formation of various PMOs. The addition of B52 in the surfactant solution improves... 

One-pot synthesis [11-14], in addition to the surface modification, is widely used for the preparation of framework-modified materials known as periodic mesoporous organosilicas (PMOs) [15]. They are synthesized by hydrolysis and condensation of bis(trialkoxysilyl) organic precursors and related compounds in the presence of both ionic and nonionic templates. In contrast to the conventional OMOs that possess surface organic groups [2, 8-14], the PMO framework contains Si-R-Si linkages (where R is an organic bridging spacer) [15]. 

G. A. (1999) Periodic mesoporous organosilicas, PMOs fusion of organic and inorganic chemistry inside the channel walls of hexagonal mesoporous silica. Chem. Commun., (24), 2539-2540 ... 

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