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Abstract: A new efficient composite catalyst (CuIMnFeIIIO/NG) for oxygen reduction reaction (ORR) in both alkaline and neutral media, is successfully prepared via a facile, clean, low‐cost and reproducible solvothermal method without any further treatments. The nanoparticles consisting of crystalline phases of Fe2O3, MnCO3 and amorphous Cu2O&MnxOy (CuIMnO), are anchored on nitrogen‐doping graphene (N/C atomic ratio up to 10.56 %), which offer various active sites toward ORR. The synergistic catalytic effect between these components affords excellent ORR performance with comparable onset potential and current density to commercial Pt/C in both pH‐situations, and a 4‐electron‐transfer path during oxygen reduction. Furthermore, comparative experiment results are discussed to describe the different degrees of ORR contribution in different medium from metal species and nitrogen doping. Meanwhile, superior methanol tolerance and high stability of CuIMnFeIIIO/NG can make it a promising alternative for expensive commercial Pt‐based electrocatalysts in corresponding alkaline and neutral fuel cells. [ABSTRACT FROM AUTHOR]

The vacuum tube method has been used for the construction of nondestructive and physically stable graphitic carbon nitride/graphene nanoplatelet composites and their photocatalytic behavior studied by measuring different photoactivities, such as photocurrent, photoluminescence, and the photodegradation of tetracycline hydrochloride under visible‐light irradiation. The formation of a heterojunction was confirmed by XRD, TEM, SEM, FTIR, XPS, and Raman spectroscopy. The results of this research indicate that the vacuum tube method is a facile, economic, and environmentally friendly approach to the preparation of composites. An ion‐trapping experiment indicated that, under visible light, the most effective photocatalyst generated the superoxide radical (O2·–) and holes (h+) to achieve the complete degradation of tetracycline hydrochloride. [ABSTRACT FROM AUTHOR]