The cathodic oxygen reduction reaction (ORR) is an active area of research because of its crucial role in electrochemical energy conversion in fuel cells. [1][2][3][4] One of the most attractive challenges in this area is the development of efficient ORR electrocatalysts for application in fuel cells. In the past, considerable effort has been devoted to the study of platinum and platinum-based metal alloy electrocatalysts. [5][6][7][8][9][10][11][12] Although much progress has been made, this noble metal catalyst and its alloy can hardly meet the demands which allow for widespread commercialization of fuel cells because of their sluggish electron-transfer kinetics, [13] high costs, limited supply, [14] and poor durability [15] . Platinum-free, [16][17][18] non-noble metal, [15,[19][20][21] and metal-free [3,4,22,23] catalysts have been developed and evaluated to improve the performance and to reduce the costs of ORR electrocatalysts. Consequently, metal-free catalysts have attracted much interest because of their increased electrocatalytic activity inr the ORR and their better stability, and provide an opportunity to develop a new generation of catalysts. However, most of these metal-free catalysts doped with nitrogen were prepared by using metal catalysts (especially, Fe). Therefore, it is difficult to distinguish whether the catalytic activity of a carbon catalyst is caused by its unique electronic properties or by some metal residue. [24] Phosphorus, an element of the nitrogen group, has the same number of valence electrons as nitrogen and often shows similar chemical properties. Although the electrocatalytic activity of N-doped carbon materials for the ORR has been widely investigated, [25,26] to our knowledge, there has been no report on the performance of P-doped carbon materials for the ORR. Herein, we have prepared a P-doped graphite layer catalyst without any metal residue and we examined its electrochemical properties. The results prove that this catalyst shows high electrocatalytic activity, longterm stability, and excellent tolerance to cross-over effects of methanol in the oxygen reduction reaction in an alkaline medium. Such a metal-free catalyst can not only be used as a facile and effective alternative to platinum and platinumbased catalysts for the ORR, but it allows determination of whether the electrocatalytic activity of a heteroatom-doped carbon catalyst for the ORR is caused by its unique electronic properties or by some metal residue. [27,28]

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A new type of intermolecular bond, termed a blueshifting halogen bond, is found in the chlorotrifluoromethane-, bromotrifluoromethane-, chlorotrifluorosilicane-, and chlorodifluoroamine-related complexes. Counterpoisecorrected gradient optimization performed at a correlated ab initio level (MP2(full)/6-311++G(d,p)) shows a shortening of the C-Cl (C-Br, Si-Cl, or N-Cl) bond of the proton donor and a blueshifting of the corresponding C-Cl (C-Br, Si-Cl, or N-Cl) stretching frequency. In contrast to the conventional hydrogen bond and the blueshifting hydrogen bond, the topological and electronic properties and the origin of blueshifting halogen bond are also investigated.

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