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Converting CO2 to value‐added chemicals, e. g., CH3OH, is highly desirable in terms of the carbon cycling while reducing CO2 emission 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−1 per 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 FROM AUTHOR]

Bimetallic nanoalloys have attracted great research interest in the past decades by virtue of their tunable metal‐metal synergies. The preparation of well‐defined bimetallic nanoalloys largely relies on the use of capping ligands, which brings a great challenge to utilize the surface‐accessible active sites and/or tailor bimetallic‐support interactions. In the current paper, surface‐clean, thermally stable and monodisperse PdAu nanoalloys confined in mesoporous TiO2 (PdAu@mTiO2) were prepared using evaporation‐induced self‐assembly with two colloidal templates. The hydrogenation activity of PdAu@mTiO2 was demonstrated to be approximately 6 times higher than that of PdAu nanoalloys supported on mesoporous silica due to the bimetallic‐support interactions. Our method is expected to open up new opportunities to synthesize ligand‐free and stable bimetallic nanoalloys with tailored bimetallic‐support interactions for highly efficient catalysis. [ABSTRACT FROM AUTHOR]