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Abstract Converting CO₂to value‐added chemicals,e. g., CH₃OH, is highly desirable in terms of the carbon cycling while reducing CO₂emission from fossil fuel combustion. Cu‐based nanocatalysts are among the most efficient for selective CO₂‐to‐CH₃OH transformation; this conversion, however, suffers from low reactivity especially in the thermodynamically favored low temperature range. We herein report ultrasmall copper (Cu) nanocatalysts supported on crystalline, mesoporous zinc oxide nanoplate (Cu@mZnO) with notable activity and selectivity of CO₂‐to‐CH₃OH in the low temperature range of 200–250 °C. Cu@mZnO nanoplates are prepared based on the crystal‐crystal transition of mixed Cu and Zn basic carbonates to mesoporous metal oxides and subsequent hydrogen reduction. Under the nanoconfinement of mesopores in crystalline ZnO frameworks, ultrasmall Cu nanoparticles with an average diameter of 2.5 nm are produced. Cu@mZnO catalysts have a peak CH₃OH formation rate of 1.13 mol h⁻¹per 1 kg under ambient pressure at 246 °C, about 25 °C lower as compared to that of the benchmark catalyst of Cu−Zn−Al oxides. Our new synthetic strategy sheds some valuable insights into the design of porous catalysts for the important conversion of CO₂‐to‐CH₃OH. 

Abstract Propane and propene oxidations on M1 phase MoVTeNb mixed oxide catalysts exhibit relatively high selectivity to acrolein and acrylic acid. We probe the ability of the reactant molecules to access the catalytic sites inside the heptagonal pores of these oxides and analyze elementary steps that limit selectivity. Measured propane/cyclohexane activation rate ratios on MoVTeNbO are nearly an order of magnitude higher than non‐microporous VO_x/SiO₂, which suggests significant contribution of M1 phase pores to propane activation because both molecules react via homologous rate‐limiting C−H activation. Density functional theory suggests that desired C₃H₈dehydrogenation and C₃H₆allylic oxidation to acrolein and acrylic acid are limited by C−H activation steps, while less valuable oxygenates form via steps limited by C−O bond formation. Calculated activation barriers for C−O formation are invariably higher than C−H activation when these activations occur inside the pores, suggesting that reactions restricted within the pores are highly selective to desired products. These results demonstrate the role of pore confinement and a framework to assess selectivity limitation in hydrocarbon oxidations involving a complex network of sequential and parallel steps. 

Abstract A colloidal‐amphiphile‐templated growth is developed to synthesize mesoporous complex oxides with highly crystalline frameworks. Organosilane‐containing colloidal templates can convert into thermally stable silica that prevents the overgrowth of crystalline grains and the collapse of the mesoporosity. Using ilmenite CoTiO₃as an example, the high crystallinity and the extraordinary thermal stability of its mesoporosity are demonstrated at 800 °C for 48 h under air. This synthetic approach is general and applicable to a series of complex oxides that are not reported with mesoporosity and high crystallinity, such as NiTiO₃, FeTiO₃, ZnTiO₃, Co₂TiO₄, Zn₂TiO₄, MgTi₂O₅, and FeTi₂O₅. Those novel materials make it possible to build up correlations between mesoscale porosity and surface‐sensitive physicochemical properties, e.g., electromagnetic response. For mesoporous CoTiO₃, there is a 3 K increase of its antiferromagnetic ordering temperature, compared with that of nonporous one. This finding provides a general guideline to design mesoporous complex oxides that allow exploring their unique properties different from bulk materials.