Partial Hydrolysis of Diphosphonate Ester During the Formation of Hybrid TiO Nanoparticles: Role of Acid Concentration.

The hydrolysis of the phosphonate ester linker during the synthesis of hybrid (organic-inorganic) TiO nanoparticles is important when forming porous hybrid organic-inorganic metal phosphonates. In the present work, a method was utilized to control the in-situ partial hydrolysis of diphosphonate ester in the presence of a titania precursor as a function of acid content, and its impact on the hybrid nanoparticles was assessed. Organodiphosphonate esters, and more specific, their hydrolysis degree during the formation of hybrid organic-inorganic metal oxide nanoparticles, are relatively under explored as linkers.

Self-Induced and Progressive Photo-Oxidation of Organophosphonic Acid Grafted Titanium Dioxide.

While synthesis-properties-performance correlations are being studied for organophosphonic acid grafted TiO , their stability and the impact of the exposure conditions on possible changes in the interfacial surface chemistry remain unexplored. Here, the impact of different ageing conditions on the evolution of the surface properties of propyl- and 3-aminopropylphosphonic acid grafted mesoporous TiO over a period of 2 years is reported, using solid-state P and C NMR, ToF-SIMS and EPR as main techniques. In humid conditions under ambient light exposure, PA grafted TiO surfaces initiate and facilitate photo-induced oxidative reactions, resulting in the formation of phosphate species and degradation of the grafted organic group with a loss of carbon content ranging from 40 to 60 wt %.

Selective Pd recovery from acidic leachates by 3-mercaptopropylphosphonic acid grafted TiO: does surface coverage correlate to performance?

Modification of metal oxides with organophosphonic acids (PAs) provides the ability to control and tailor the surface properties. The metal oxide phosphonic acid bond (M-O-P) is known to be stable under harsh conditions, making PAs a promising candidate for the recovery of metals from complex acidic leachates. The thiol functional group is an excellent regenerable scavenging group for these applications.

Amino-Alkylphosphonate-Grafted TiO: How the Alkyl Chain Length Impacts the Surface Properties and the Adsorption Efficiency for Pd.

Amino-alkylphosphonic acid-grafted TiO materials are of increasing interest in a variety of applications such as metal sorption, heterogeneous catalysis, CO capture, and enzyme immobilization. To date, systematic insights into the synthesis-properties-performance correlation are missing for such materials, albeit giving important know-how towards their applicability and limitations. In this work, the impact of the chain length and modification conditions (concentration and temperature) of amino-alkylphosphonic acid-grafted TiO on the surface properties and adsorption performance of palladium is studied.