Many different aerogel materials are known to be accessible via the controlled destabilization of the respective nanoparticle suspensions. Especially for applications in heterogeneous catalysis such materials with high specific surface areas are highly desirable. Here, a facile method to obtain a mixed ZnPd/ZnO aerogel via a reductive treatment of a preformed Pd/ZnO aerogel is presented. Different morphologies of the Pd/ZnO aerogels could be achieved by controlling the destabilization of the ZnO sol. All aerogels show a high CO2 selectivity of up to 96% and a very good activity in methanol steam reforming that delivers hydrogen, which is one of the most important fuels for future energy concepts. The method presented is promising for different transition metal/metal oxide systems and hence opens a path to a huge variety of materials

Catalysts were prepared by impregnation-based method involving excess Cl− anion addition to the metal chloride precursors which resulted in improved mixing of metals and led to formation of highly ordered PdZn alloys responsible for high catalytic selectivity.

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Single‐phase ZnPd with different elemental composition as well as ZnO‐supported ZnPd nanoparticles were prepared and tested concerning their catalytic properties in the formic acid decomposition with the aim to investigate a possible formate pathway in the steam reforming of methanol (MSR). Pd‐rich ZnPd showed higher catalytic activity than ZnPd with lower Pd content. All samples showed high and stable CO2 selectivity. The stability of the materials was investigated both ex situ by powder X‐ray diffraction (XRD), scanning electron microscopy (SEM), and Raman spectroscopy after formic acid decomposition as well as by in situ X‐ray photoelectron spectroscopy (in situ XPS) and operando differential thermal analysis–thermogravimetry (DTA/TG). Samples with higher Pd content exhibited higher stability against oxidation, corroborating earlier observations under MSR conditions. The supported ZnPd/ZnO material and Zn‐rich bulk ZnPd samples showed a strong modification after reaction, which is attributed to zinc formate formation during formic acid decomposition. Kinetic data give strong indications to exclude dehydrogenation of a formate intermediate as rate‐limiting step in MSR.