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[Display omitted] • An extension of classic deep oxidation CuMnOx catalysts to selective oxidation of alcohol with high efficiency. • CuMnOx catalysts characterized by Mn 2 O 3 -Cu 1.4 Mn 1.6 O 4 and CuO-Cu 1.4 Mn 1.6 O 4 oxide pairs. • Mn 2 O 3 -Cu 1.4 Mn 1.6 O 4 oxide pair is more active than CuO-Cu 1.4 Mn 1.6 O 4 oxide pair. • Rich Cu+ species in Mn 2 O 3 -Cu 1.4 Mn 1.6 O 4 oxide pair is essential to achieve high catalytic activity. This work presents an extension of classic deep oxidation CuMnOx catalysts to a selective oxidation of alcohol with high efficiency and in an environmental-friendly reaction system. A series of CuMnOx catalysts characterized by CuO-Cu 1.4 Mn 1.6 O 4 and Mn 2 O 3 -Cu 1.4 Mn 1.6 O 4 oxide pairs were prepared via a novel half carbonized citrus grandis peel assisted hard template method. A shift of the oxide pairs from CuO-Cu 1.4 Mn 1.6 O 4 to Mn 2 O 3 -Cu 1.4 Mn 1.6 O 4 has been achieved by tuning Cu/Mn molar ratio, and then leads to a one-pass benzaldehyde yield more than 50% with 100% benzaldehyde selectivity in the selective oxidation of benzyl alcohol using H 2 O 2 as oxidant. Higher relative amount of Cu 1.4 Mn 1.6 O 4 in either Mn 2 O 3 -Cu 1.4 Mn 1.6 O 4 or CuO-Cu 1.4 Mn 1.6 O 4 oxide pair is found to be essential for achieving high catalytic activity. The interaction between the Cu 1.4 Mn 1.6 O 4 constituent and Mn 2 O 3 constituent of Mn 2 O 3 -Cu 1.4 Mn 1.6 O 4 oxide pair is found to able to enhance the formation of Cu+ species, which can reacts with H 2 O 2 to produce •OH and then touch off a Fenton-like catalytic oxidation process of benzyl alcohol, in the current CuMnOx-H 2 O 2 system, to produce benzaldehyde with high selectivity. This work presents a new perspective in the development of highly effective and low cost CuMnOx catalysts for heterogeneous catalytic oxidation reactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new understanding in the active site of CuMnOx catalysts. • CuMnOx catalysts are composed by uniform CuO-Mn 2 O 3 oxide pairs. • Highly isolated CuO nano-particles are essential for CuO-Mn 2 O 3 oxide pairs. • Cu-O-Mn sites are found to be the active sites of CuO-Mn 2 O 3 oxide pairs. The current work provide a new understanding on the active site of CuMnOx catalysts and thus offer a new perspective in the development of highly effective and low cost CuMnOx catalysts for heterogeneous catalytic oxidation reactions. A series of dual-component copper-manganese multi-oxide catalysts (CuMnOx) have been successfully synthesized using a surfactant assisted hydrolysis-hydrothermal method and studied by XRD, N 2 adsorption–desorption test, ICP-AES, SEM, Aberration-corrected HADDF-STEM, HRTEM, FT-IR, Raman, XPS, H 2 -TPR. These CuMnOx catalysts were found to be composed with uniform CuO-Mn 2 O 3 oxide pair structure, in which highly isolated/dispersed CuO species are anchored in the framework of Mn 2 O 3. It was found that the speciation in these CuMnOx catalysts presents a shift from highly isolated or even single Cu2+ oxide species (Cu2+Ox) to CuO nanoclusters and CuO microcrystalline with increasing Cu content. In CO oxidation reaction, which was employed to probe the structure of the CuO-Mn 2 O 3 oxide pairs in these CuMnOx catalysts, the Cu-O-Mn sites in those CuMnOx catalysts with highly isolated or highly dispersed CuO species were found to be highly active. For CuO-Mn 2 O 3 oxide pair catalysts, the highly isolated/dispersed CuO species in Mn 2 O 3 framework is essential to achieve high activity. [ABSTRACT FROM AUTHOR]