Who Does the Job? How Copper Can Replace Noble Metals in Sustainable Catalysis by the Formation of Copper-Mixed Oxide Interfaces.

Following the need for an innovative catalyst and material design in catalysis, we provide a comparative approach using pure and Pd-doped LaCu Mn O ( = 0.3 and 0.5) perovskite catalysts to elucidate the beneficial role of the Cu/perovskite and the promoting effect of Cu Pd /perovskite interfaces developing under model NO + CO reaction conditions.

Elucidating the role of earth alkaline doping in perovskite-based methane dry reforming catalysts.

To elucidate the role of earth alkaline doping in perovskite-based dry reforming of methane (DRM) catalysts, we embarked on a comparative and exemplary study of a Ni-based Sm perovskite with and without Sr doping. While the Sr-doped material appears as a structure-pure SmSrNiO Ruddlesden Popper structure, the undoped material is a NiO/monoclinic SmO composite. Hydrogen pre-reduction or direct activation in the DRM mixture in all cases yields either active Ni/SmO or Ni/SmO/SrCO materials, with albeit different short-term stability and deactivation behavior.

The sol-gel autocombustion as a route towards highly CO-selective, active and long-term stable Cu/ZrO methanol steam reforming catalysts.

The adaption of the sol-gel autocombustion method to the Cu/ZrO system opens new pathways for the specific optimisation of the activity, long-term stability and CO selectivity of methanol steam reforming (MSR) catalysts. Calcination of the same post-combustion precursor at 400 °C, 600 °C or 800 °C allows accessing Cu/ZrO interfaces of metallic Cu with either amorphous, tetragonal or monoclinic ZrO, influencing the CO selectivity and the MSR activity distinctly different. While the CO selectivity is less affected, the impact of the post-combustion calcination temperature on the Cu and ZrO catalyst morphology is more pronounced.

Steering the Catalytic Properties of Intermetallic Compounds and Alloys in Reforming Reactions by Controlled Decomposition and Self-Activation.

Based on the increasing importance of intermetallic compounds and alloys in heterogeneous catalysis, we explore the possibilities of using selected intermetallic compounds and alloy structures and phases as catalyst precursors to prepare highly active and CO-selective methanol steam reforming (MSR) as well as dry reforming of methane (DRM) catalyst entities by controlled decomposition and self-activation. The exemplary discussed examples (CuZr, CuZn, PdZr, GaPd, CuIn, ZnPd, and InPd) show both the advantages and pitfalls of this approach and how the concept can be generalized to encompass a wider set of intermetallic compounds and alloy structures. Despite the common feature of all systems being the more or less pronounced decomposition of the intermetallic compound surface and bulk structure and the formation of much more complex catalyst entities, differences arise due to the oxidation propensity and general thermodynamic stability of the chosen intermetallic compound/alloy and their constituents.

Steering the Methane Dry Reforming Reactivity of Ni/LaO Catalysts by Controlled In Situ Decomposition of Doped LaNiO Precursor Structures.

The influence of A- and/or B-site doping of Ruddlesden-Popper perovskite materials on the crystal structure, stability, and dry reforming of methane (DRM) reactivity of specific ABO phases (A = La, Ba; B = Cu, Ni) has been evaluated by a combination of catalytic experiments, in situ X-ray diffraction, X-ray absorption spectroscopy (XAS), X-ray photoelectron spectroscopy (XPS), and aberration-corrected electron microscopy. At room temperature, B-site doping of LaNiO with Cu stabilizes the orthorhombic structure () of the perovskite, while A-site doping with Ba yields a tetragonal space group (4/). We observed the orthorhombic-to-tetragonal transformation above 170 °C for LaNiCuO and LaNiCuO, slightly higher than for undoped LaNiO.