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Graphical abstract Highlights • Ozone-assisted catalysis was able to remove CO efficiently at room temperature. • Bimetallic Ag-Pd catalyst exhibited a cooperative effect. • In situ FTIR measurement provided useful insights into the mechanism of the catalytic reaction. Abstract The room-temperature oxidation of CO using ozone-assisted catalysis (OAC) over monometallic or bimetallic catalysts supported on γ-Al 2 O 3 is presented. Within the tested particle size range, ozone decomposition was insensitive to the size of the Ag particles (6.6–11.9 nm) at weight hourly space velocities of up to 360 L·g−1·h−1. Among the tested monometallic catalysts (Ag Pd, Fe, Mn, and Cu), Ag showed the highest activity for CO oxidation. Bimetallic catalysts (Ag-M or Pd-M where M = Cu, La, Ru, and Fe) were also considered by adding a second metal or perovskite oxide (LaFeO 3) to Ag. A cooperative effect was observed with the bimetallic Ag-Pd catalyst for the OAC of CO oxidation at room temperature, whereas the other bimetallic catalysts showed slightly lower performance compared to the monometallic catalyst. A high ozone utilization efficiency of 0.94 was achieved with the bimetallic Ag-Pd/γ-Al 2 O 3 catalyst. High-angle annular dark-field scanning tunneling electron microscopy (HAADF) and energy dispersive X-ray (EDX) spectroscopy measurements confirmed the proximity of the two components, which is essential for their interaction. The in situ FTIR measurements revealed that the cooperative effect in the bimetallic Ag-Pd catalyst involved modification of CO adsorption and the suppression of product accumulation. Two typical IR absorption bands of linear- (2090 cm−1) and bridge-CO (1918 cm−1) on Pd disappeared in the presence of Ag nanoparticles. Thus, the presence of Ag in contact with Pd inhibited the accumulation of carbonates, which led to enhanced catalytic performance. Adsorption site-dependent CO oxidation on Pd was also confirmed by the in situ Fourier transform IR measurement. [ABSTRACT FROM AUTHOR]

Highly dispersed bimetallic AgPd nanoparticles with different composition have been successfully deposited on the metal-organic frameworks (ZIF-8) by using a simple liquid impregnation method. The resultant catalysts are composition dependent toward dehydrogenation of formic acid, while Ag 18 Pd 82 @ZIF-8 exhibits exceedingly high catalytic activity, with the turnover frequency (TOF) value of 580 h −1 , and 100% hydrogen selectivity at 80 °C. [ABSTRACT FROM AUTHOR]

Monodispersed bimetallic PdAg nanoparticles can be fabricated through the emulsion-assisted ethylene glycol (EG) ternary system. Different compositions of bimetallic PdAg nanoparticles, Pd80Ag20, Pd65Ag35 and Pd46Ag54 can be obtained via adjusting the reaction parameters. For the formation process of the bimetallic PdAg nanoparticles, there have two-stage growth processes: firstly, nucleation and growth of the primary nanoclusters; secondly, formation of the secondary nanoparticles with the size-selection and relax process via the coalescence or aggregation of the primary nanoclusters. The as-prepared PdAg can be supported on the carbon black without any post-treatment, which exhibited high electro-oxidation activity towards methanol oxidation under alkaline media. More importantly, carbon-supported Pd80Ag20 nanoparticles reveal distinctly superior activities for the methanol oxidation, even if compared with commercial Pt/C electro-catalyst. It is concluded that the enhanced activity is dependant on the unique twinning structure with heterogeneous phase due to the dominating coalescence growth in EG ternary system. [ABSTRACT FROM AUTHOR]