Ernesto Schulz Lang

Representatives of the novel dinuclear gold( i ) diphosphine metallacycles derived from bis(thiosemicarbazides) featuring unique structural architectures stabilized by strong, fully supported aurophilic interactions forming large internal cavities.

Novel nickel complexes with dioxo-haloselenate anion act as cocatalysts for m-TiO₂, enhancing H₂ production through visible light absorption and photocatalytic activity.

Four photocatalysts solids were designed using a new Pd−Te complex, [Pd₂(μ‐TePh)₂(bipy)₂](PF₆)₂, immobilized over titania to improve its solar energy harvesting ability for enhancing H₂ production by water splitting under sunlight (300 W Xe/Hg lamp). Firstly, the photocatalytic performance for H₂ production of the porous TiO₂ supports (m‐TiO₂), synthesized with varying textural properties and anatase/rutile contents, were compared. Furthermore, cyclic voltammetry measurements revealed that the Pd−Te complex can catalyze protons to hydrogen under weak acidic conditions. Then, different wt % concentrations of the complex were immobilized over the m‐TiO₂ of the greatest performance and also over Degussa P25 (commercial titania) for photocatalytic comparison. Among the newly designed photocatalysts, the one containing only 4 wt% of Pd−Te complex over m‐TiO₂ showed the greatest hydrogen production (3631 μmol g⁻¹ h⁻¹), which is 69 times greater than that of the pure m‐TiO₂ and 378 times higher than that of the pure Pd−Te complex. These results suggested the crucial role of the Pd−Te complex when combined with m‐TiO₂, promoting greater photocatalytic performance compared to the pure support. This outcome inspires an extensive investigation of metal complexes combined with semiconductors to improve their ability for photocatalytic H₂ production by water splitting under sunlight.

In this work, zinc oxide with different morphologies and textural properties were prepared and sensitized with metalloporphyrins (MPs) aiming to improve its solar energy harvesting capability for H₂ production by water splitting under sunlight (a 300 W Xe/Hg lamp). An anionic iron(III)porphyrin and a cationic manganese(III)porphyrin were immobilized on different ZnO solids predominantly by electrostatic interactions. In general, the prepared MP‐free ZnO solid yielded modest catalytic results which had apparently no direct correlation with their textural properties or morphology. On the other hand, when these ZnO solids had iron or manganese porphyrin sensitizing them, their catalytic performances changed and a superior yield towards H₂ production was observed in comparison to the pure ZnO solids, making evident the synergy achieved between these two components (ZnO and metalloporphyrins) for the prepared solids. It was also observed that the metalloporphyrins and the respective free‐base ligand suffered redox reactions when used as homogenous catalyst in this reaction, which could influence their performances as catalysts. The same was not observed in the solids containing immobilized MP, suggesting some protective effect of the ZnO solids on the MP complexes upon immobilization probably due to interaction of the complexes with the ZnO matrix.

Hydrolysis of PhTeI3 in the presence of sodium phenylseleninate and M3+ ions (M = Y, Nd, Ce) gives well-defined, bowl-shaped telluroxane clusters. Each of the two half-spheres of the compositions [(PhTe)(18){ML}O-24](7+/8+) ({ML} = {Y(NO3)(H2O)}(2+) (1), {Nd(NO3)(H2O)(2+)} (2), or {Ce(NO3)(2)}(+) (3)) are connected by two (compound 3) or four (compounds 1 and 2) PhSeO2- bridges. The resulting chalcogenoxane spheres have internal volumes of approximately 1500 & Aring;(3). Charge compensation is provided by nitrate ions and/or [Na-2(NO3)(8)](6-) clusters, which are located inside and surrounding these spheres.