Royal Society of ChemistryBrahmi, Y.; Katir, N.; Macia Agullo, JA.; Primo Arnau, AM.; Bousmina, M.; García Gómez, H.; El Kadib, A. (2015). The sol-gel co-condensation of organo-phosphonate to titanium alkoxide enables access to novel organic-inorganic hybrids based on phosphonate-bridged titanium dioxide. In this contribution, we bring new perspectives to the long established solgel mineralization of titanium alkoxide species, by harnessing the virtues of the well-designed phosphonate-terminated phosphorus dendrimers as reactive amphiphilic nanoreactor, confined medium and cross-linked template to generate at low temperature synthesis (T = 60°C), discrete crystalline anatase nanoparticles. An accurate investigation on several parameters (dendrimer generation, dendrimer-to-titanium alkoxide ratio, precursor reactivity, temperature, solvent nature, salt effect) allows a correlation between the network condensation, the opening porous framework and the crystalline phase formation. The evolution of the dendrimer skeletal upon heat treatment has been deeply monitored by means of 31 P NMR, XPS and RAMAN spectroscopies. Increasing the heteroatom content within titania network provides the driving force for enhancing their photocatalytic water splitting ability for hydrogen production.