Hybrids containing zirconium and phosphorus compounds obtained by sol-gel method

In the present work, novel organic-inorganic hybrids containing zirconium and phosphorus compounds were synthesized by using the sol-gel method, starting from zirconyl chloride hexahydrate (ZrOCl2·6H2O) and phenyl phosphonic acid (PPA). All the syntheses were performed at room temperature by using water as solvent. For some of the performed syntheses, alcohols with long hydrocarbon chain (n = 4–8) were added to the sol-gel process. They behave as nonionic surfactants due to their hydrophobic and hydrophilic groups, and they decrease the surface tension but without micelles formation, therefore without reaching CMC (critical micellar concentration). At a certain concentration, they will phase separate. This leads to the formation of a liquid/liquid interface. When the used alcohols were more hydrophobic, the obtained interface was more stable. This helped the synthesis and significantly changed its kinetics, as follows: in water, the chemical reaction was finished in 6 h, but when heptanol or octanol were added, the reaction time decreased to 3 h.