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[Display omitted] • Green Fenton-like selective oxidation of alcohol driven by the active oxygen species from air. • Highly efficient selective oxidation with low-cost and super-facile reaction operation. • Highly efficient MnCoOx catalysts characterized by uniform MnCo 2 O 4 -Co 3 O 4 oxide pair for selective oxidation of alcohol using air as oxidant. • A facile method with an in - situ heating enhancement for the formation of spinel MnCo 2 O 4 mixed oxide. Mn reinforced Co 3 O 4 catalysts (MnCoOx) were prepared by a facile solid phase mixed foaming method with an in-situ heating enhancement for the formation of spinel phase mixed oxide species, and studied in the selective oxidation of benzyl alcohol just the air in reactor as oxygen donor. It was found that the MnCoOx catalysts are composed of relatively minimal spinel MnCo 2 O 4 mixed oxide and massive Co 3 O 4 to form MnCo 2 O 4 -Co 3 O 4 oxide pair. The micro-domains of MnCo 2 O 4 -Co 3 O 4 oxide pair present two redox couples of Mn3+/Mn2+ and Co3+/Co2+ instead of the single one of Co3+/Co2+ in Co 3 O 4 , and then dramatically enhance the formation of superoxide radicals (•O2–) species from the O 2 in air, which can efficiently initiate the conversion of benzyl alcohol to benzaldehyde in a Fenton-like processes. With no oxidant other than air in reactor, the interaction between MnCo 2 O 4 and Co 3 O 4 in MnCoOx catalysts leads to a benzyl alcohol conversion up to 98 % with a 100 % benzaldehyde selectivity at atmospheric pressure while single component Co 3 O 4 can only present a benzyl alcohol conversion at 37 %. This embodiment of highly efficient heterogeneous selective oxidation just with air as oxidant provides a probability for developing a low-cost and super-facile radical-induced selective oxidation process for alcohols. [ABSTRACT FROM AUTHOR]

[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]