Correction : Transition metal hollow nanocages as promising cathodes for the long-term cyclability of Li–O2 batteries(Nanomaterials, (2018), 8): Transition metal hollow nanocages as promising cathodes for the long-term cyclability of Li–O₂ batteries(Nanomaterials, (2018), 8)

The authors wish to add the following information to this paper [1]. The last paragraph of Section 1 in the Introduction has been replaced by the following two paragraphs: One of the drawbacks of using these spinel structured oxides is their low surface area [12]. In our previous work [16], we have announced the preliminary results and initial observations on the basic morphology and magnetism of a highly porous spinel-type, Mn₃O₄, called Mn₃O₄ hollow nanocages (MOHNs), in addition to the general electrochemical performance of MOHNs/Ketjenblack (KB) cathode-based Li-O₂ batteries. It has been demonstrated that the use of a simple facile template assisted growth technique is capable of producing crystalline paramagnetic MOHNs composed of many 25 nm mean diameter Mn₃O₄ nanoparticles, loosely agglomerated together to form the shell of a mesoporous hollow nanocage structure with a large mean diameter of 250 nm and a high surface area of 90.65 m²·g^-1. Moreover, the resulting MOHNs/KB cathode-based Li-O₂ batteries exhibit more than 50 discharge-charge cycles at a reversible restrained specific capacity of 600 mAh·g^-1 and a specific current of 400 mA·g^-1. This paper is extended from the previous proceedings paper [16]. It broadens the previous focus on the physical aspect of MOHNs to the physicochemical aspect of MOHNs. We thereby provide a more comprehensive evaluation and elaboration on the physicochemical properties and formation mechanism of MOHNs, as well as the electrochemical performance of MOHNs/KB cathode-based Li-O₂ batteries. An analysis of death batteries is also performed, in order to understand how the mesoporous hollow nanocage structure of MOHNs provides a pathway for better diffusion of reactants and products, how it prevents the blockage of pores from Li-O₂, and how it improves the cyclic stability of Li-O₂ batteries. The figure captions of Figures 2-5 are added with the following statements: Figure 2a is reproduced with permission from [16]. Copyright IEEE, 2018. Figure 3b is reproduced with permission from [16]. Copyright IEEE, 2018. Figure 4a,d are reproduced with permission from [16]. Copyright IEEE, 2018. Figure 5 is reproduced with permission from [16]. Copyright IEEE, 2018. The authors regret any inconvenience or misunderstanding caused by these errors. The manuscript will be updated and the original will remain available on the article webpage.