Epitaxial Core/Shell Nanocrystals of (Europium-Doped) Zirconia and Hafnia.

A careful design of the nanocrystal architecture can strongly enhance the nanocrystal function. So far, this strategy has faced a synthetic bottleneck in the case of refractory oxides. Here we demonstrate the epitaxial growth of hafnia shells onto zirconia cores and pure zirconia shells onto europium-doped zirconia cores.

Synthesis of zirconium(IV) and hafnium(IV) isopropoxide, -butoxide and -butoxide.

We revisited the synthesis of zirconium(IV) and hafnium(IV) alkoxides, namely the metal isopropoxide isopropanol complex (M(OiPr)·iPrOH, M = Zr, Hf) and the metal - and -butoxide (M(OBu) and M(OBu), M = Zr, Hf). We optimized the most convenient synthesis methods and compared the products with commercial sources. En route to the metal - and -butoxides, we synthesized the metal diethylamido complex (M(NEt), M = Zr, Hf).

Complexation and disproportionation of group 4 metal (alkoxy) halides with phosphine oxides.

Group 4 Lewis acids are well-known catalysts and precursors for (non-aqueous) sol-gel chemistry. Titanium, zirconium and hafnium halides, and alkoxy halides are precursors for the controlled synthesis of nanocrystals, often in the presence of Lewis base. Here, we investigate the interaction of Lewis bases with the tetrahalides (MX, X = Cl, Br) and metal alkoxy halides (MX(OR), = 1-3, R = OPr, OBu).

Molecular Insights into Sequence-Specific Protein Hydrolysis by a Soluble Zirconium-Oxo Cluster Catalyst.

The development of catalysts for controlled fragmentation of proteins is a critical undertaking in modern proteomics and biotechnology. {ZrO}-based metal-organic frameworks (MOFs) have emerged as promising candidates for catalysis of peptide bond hydrolysis due to their high reactivity, stability, and recyclability. However, emerging evidence suggests that protein hydrolysis mainly occurs on the MOF surface, thereby questioning the need for their highly porous 3D nature.