Research

Research Focus of the Mascotto Group

At the Laboratory for Functional Ceramic Materials (LFCM) at the University of Koblenz, we develop inorganic nanomaterials with tailored surface properties for heterogeneous catalysis. Surface chemistry and surface morphology are deliberately engineered to meet specific application requirements. A central theme is the sustainable synthesis of nanostructured metal oxides with controlled defect structures. Particular emphasis is placed on the real-time investigation of structure–property relationships (e.g., ionic transport) using spectroscopic and scattering techniques.

Functional Nanostructured Inorganic Materials

Selected metal oxide nanostructures fabricated in our group (from left: mesoporous thin films, nanoparticles, and mesoporous powders).

Increasing the specific surface area and shortening charge carrier diffusion pathways are key to developing high-performance materials for catalysis and energy conversion. We synthesize nanostructured and nanoporous binary and ternary oxides (e.g., SiO₂, TiO₂, SrTiO₃, LaMnO₃) as well as carbon materials in the form of thin films, nanoparticles, and powders via wet-chemical colloidal synthesis routes. Our focus lies on template-based syntheses of mesoporous materials, precise control of pore shape and size, tuning of doping levels and solid solution formation to optimize ionic conductivity, and the stability of oxides under reactive conditions during catalytic application.

We currently focus on developing sustainable and scalable wet-chemical synthesis methods, as well as novel materials for heterogeneous catalysis.

Exsolution of Metal Nanoparticles from Metal Oxides

Exsolution process for the synthesis of regenerable, anchored Ni nanoparticles for the methanation of CO2 (schematic).

In ternary oxides such as perovskite oxides, cationic surface segregation at elevated temperatures offers an innovative route to enhancing catalytic performance. In the so-called exsolution process, metal cations segregate to the oxide surface and nucleate into metal nanoparticles. These nanoparticles are anchored within the oxide matrix and self-regenerate through oxidation–reduction cycles (Figure 2) — an elegant solution to well-known challenges such as sintering and poisoning of supported metal catalysts.

This approach enables the fabrication of not only monometallic nanoparticles (e.g., Ni, Co, Cu) but also bi- and trimetallic systems (FeNi, FeNiCo) and switchable core–shell structures (FeOx@FeNi). Precise control over temperature and gas atmosphere allows morphology and composition to be tuned with high accuracy. Such catalysts are well-suited for the sustainable conversion of CO₂ into valuable feedstocks such as methanol or short-chain alkanes.

We are currently developing new strategies for the targeted exsolution of metal nanoparticles from oxide nanostructures, with the aim of precisely controlling the structure, composition, and dynamics of exsolved nanoparticles to realize high-performance catalysts for energy- and climate-relevant reactions.

Development of In Situ Methods at Large-Scale Instruments

Photo of a developed sample environ-ment for the in situ investigation of nanoparticle formation during the exsolution process.

We investigate structure–property relationships in nanostructured inorganic materials at large-scale facilities, primarily using small-angle X-ray and neutron scattering (SAXS/SANS), as well as X-ray diffraction (XRD) and X-ray absorption spectroscopy (XANES/EXAFS). A particular focus is placed on the development of multidimensional in situ methods — i.e., the simultaneous combination of multiple analytical techniques — and corresponding sample environments for the characterization of nanoporous materials and supported catalysts at high temperatures and under various gas atmospheres. In addition, we have expertise in the characterization of nanoporous carbon materials for lithium-ion batteries, as well as polymers and polymer nanocomposites.