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N-doped carbons (NCs) have attracted considerable attention for their outstanding physicochemical properties, including tunable porosity, electronic features and modified surface. Here, we report the preparation of hierarchically porous NCs derived from the direct pyrolysis of ZIFs (ZIF-7 and ZIF-8) and poly– m –phenylenediamine-covered carbon black (P m PDA-C) for the stabilization of Cu nanoparticles (NPs). The configuration of N species can be effectively regulated by changing the ligand of ZIFs and pyrolysis atmosphere. A remarkable N configuration synergistic effect is observed in the oxy-carbonylation of methanol to dimethyl carbonate with molecular oxygen. The results indicate that the Cu NPs on pristine carbon have a turn over frequency (TOF) of 4.4 h−1 for the reaction, while those on NCs from ZIF-8 and ZIF-7 present TOF values as high as 17.9 h−1 and 28.5 h−1, respectively. The extensive characterizations reveal that NCs with a nitrogen content of 2–5 wt% and a pyrrolic-/pyridinic-N molar ratio of 2–3 are vital for the performance enhancement of Cu NPs. This work shows that the stabilization and enhanced performance of active Cu NPs on NCs are realized by the rational design of precursors to generate the proper N configurations. Image 1 • A series of NCs are prepared from ZIFs with N content in the range of 0–20 wt%. • The N configuration is regulated by ligand of ZIFs and varying pyrolysis conditions. • The performance of supported Cu catalysts is correlated with N configurations. • NCs with 2–5 wt% N and pyrrolic-/pyridinic-N ratio at 2–3 are vital for Cu catalysis. [ABSTRACT FROM AUTHOR]

• The Ag/Zr–SiO 2 catalyst is highly selective for producing unsaturated alcohol. • Significant support effect and interfacial catalysis are observed. • Enhanced acidity by zirconia doping promotes Ag dispersion and catalytic activity. • Interesting low-temperature O 2 chemisorption occurs on interfacial Ag sites. • Ternary Ag–ZrO 2 –SiO 2 interfaces favor the selective activation of C O bond. In gas-phase chemoselective hydrogenation of crotonaldehyde on Ag-based catalysts, zirconia doping on silica supports was found to improve catalytic performance in terms of unsaturated alcohol selectivity, hydrogenation activity, and stability. The surface modification of silica by zirconia doping favors the fine dispersion of Ag species due to the enhanced quantity and strength of surface acid sites, which enable construction of abundant catalytic sites effective for C O bond hydrogenation. High crotyl alcohol selectivity, exceeding 80%, and significant inhibition of monohydrogenation on the C C bond were observed on the optimal Ag/Zr–SiO 2 catalyst. Dynamic O 2 chemisorption measurement revealed that the pure Ag powders did not chemisorb O 2 irreversibly under 323 K, but SiO 2 or Zr–SiO 2 supported Ag catalysts did. The amounts of Ag active for O 2 chemisorption, which are at least one order of magnitude lower than that of surface Ag derived from TEM and XRD characterizations, match well with the perimeter interface Ag of hemispherical particles. A strong correlation between hydrogenation activity and O 2 uptake on those Ag/SiO 2 and Ag/Zr–SiO 2 catalysts with different Ag dispersions and deactivation degrees was observed, implying that the effective catalytic sites for crotonaldehyde chemoselective hydrogenation may originate from accessible interface sites with unique redox properties. Catalyst induction and deactivation were observed on both Ag/SiO 2 and Ag/Zr–SiO 2 catalysts in real catalytic operation. Changes in metal stable interface structure, rather than metal aggregation and coagulation, are assumed to be the main cause of irreversible catalyst deactivation, because the apparent Ag particle sizes changed slightly, but the oxygen chemisorption ability deteriorated considerably. Electropositive Ag sites interacting with neighboring oxygen from oxide supports at the ternary Ag–ZrO 2 –SiO 2 interface are proposed to account for highly selective C O bond hydrogenation to produce the desired unsaturated alcohol. [ABSTRACT FROM AUTHOR]