Cobalt phthalocyanine (CoPc) is supported on homemade three-dimensional graphene (3D-G) to prepare CoPc/3D-G catalysts used for oxygen reduction reaction (ORR). 3D-G is made from coal tar pitch with nano MgO as template and KOH as activation agent.Raman spectra indicate that 3D-G is multi-layered. Transmission electron microscopy images show that CoPc/3D-G retains the mesoporous foam structure of 3D-G and CoPc is dispersed homogeneously on the surface of 3D-G. CoPc/3D-G shows a half-wave potential of 0.85 V vs. RHE in oxygen-saturated solution of 0.1 M KOH, which is 50 mV higher than that of 6 wt% Pt/C. The electron transfer number of CoPc/3D-G is 3.99 at 0.65 V vs. RHE, indicating that oxygen reduction is catalyzed mainly via a four-electron process. CoPc/3D-G exhibits a current density loss of 10% after 40,000 s in chronoamperometry tests, while CoPc/C lost 17.5% after the same period.

Polytetraphenylporphyrin Co͑II͒ ͑PTPPCo͒ is obtained by heat-treating 5,10,15,20-tetra͑4-carboxyphenyl͒-porphyrin Co͑II͒ at 400°C in an argon atmosphere. Thermogravimetric analysis is used to evaluate the thermal stability of PTPPCo. Oxidation resistance of PTPPCo is measured by refluxing in Fentons reagent for 72 h. The ultraviolet-visible spectra indicate that PTPPCo is not decomposed and cobalt ion is not exfoliated. Polytetraphenylporphyrin Co/C ͑PTPPCo/C͒ is obtained by the heat-treatment of PTPPCo, which is adsorbed on Vulcan XC-72 with 6 wt % Co-N 4 loading, at 600°C in an Ar atmosphere. Cyclic voltammetry, linear sweep voltammetry, and chronoamperometry tests are performed in order to observe the catalyst durability in different conditions. Almost no performance deficiency is observed after 10,000 continuous voltammetric cycles, 200 potentiometric cycles, and 60 h of chronoamperometry test. PTPPCo/C catalysts display significant chemical stability and electrocatalytic durability. These catalysts may be useful for polymer electrolyte membrane fuel cells.Metalloporphyrin catalysts have been extensively explored as a potential replacement for Pt in the catalysis of the oxygen reduction reactions ͑ORRs͒. They are transition metal N 4 -chelates. These promising cathodic catalysts have shown reasonable activity and selectivity toward ORR. 1-4 However, practical catalysts in polymer electrolyte membrane fuel cells require strong activity and high durability, which are major barriers for metalloporphyrins.The activity and durability of transition metal macrocycles for ORR catalysis are generally considered to be significantly improved by heat-treatment. In the past several decades, heat-treatment has significantly improved the ORR durability and activity of carbonsupported macrocyclic catalysts. Tetraphenylporphyrin Co͑II͒, phthalocyanine Fe͑II͒, and Co͑II͒ tetramethoxyphenylporphyrin, adsorbed on carbon and heat-treated from 700 to 950°C in argon atmosphere, have shown relatively high activities. 5-7 However, due to the high temperature heat-treatment, the catalytic center ͑Metal-N 4 ͒ moiety can be partially or completely decomposed, forming new catalytic sites, which are no longer N 4 -macrocycles. Some research studies 7-9 claim that nanometallic face-centered metal cluster ͑Metal/N/C͒ was embedded in graphitic carbon at the surface of the catalyst after heat-treatment exceeding 700°C. Porphyrin metal decompose to ␤-metal phase under high temperature, so people want to use inexpensive, easily available material replacements for macrocyclic compounds. Pyrolyzing a mixture of metallic salt, organic precursor, and ammonia in an inert atmosphere 10-13 or loading an iron precursor such as MetalAc and phen ͑or perylenetetracarboxylic-dianhydride͒ on carbon black and then by a heattreatment in NH 3 refer to the products as Metal/N/C electrocatalysts. 14 However, the structures of these catalysts are not defined well enough for a true quantitative study. 14 In acid medium, they show poor durability due to the loss of...