Few-layered graphene networks composed of phosphorus and nitrogen dual-doped porous graphene (PNG) are synthesized via a MgO-templated chemical vapor deposition (CVD) using (NH4)3PO4 as N and P source. P and N atoms have been substitutionally doped in graphene networks since the doping takes place at the same time with the graphene growth in the CVD process. Raman spectra show that the amount of defects or disorders increases after P and N atoms are incorporated into graphene frameworks. The doping levels of P and N measured by X-ray photoelectron spectroscopy are 0.6 and 2.6 at %, respectively. As anodes for Li ion batteries (LIBs), the PNG electrode exhibits high reversible capacity (2250 mA h g(-1) at the current density of 50 mA g(-1)), excellent rate capability (750 mA h g(-1) at 1000 mA g(-1)), and satisfactory cycling stability (no capacity decay after 1500 cycles), showing much enhanced electrode performance as compared to the undoped few-layered porous graphene. Our results show that the PNG is a promising candidate for anode materials in high-rate LIBs.

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We report for the first time an experimental investigation of gas storage in porous graphene with nanomeshes. High capacity methane storage (236 v(STP)/v) and a high selectivity to carbon dioxide adsorption were obtained in the nanomesh graphene with a high specific surface area (SSA) and a SSA-lossless tightly stacking manner.

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Here, we report a novel Co 3 O 4 -graphene hybrid electrode material with high density Co 3 O 4 nanoparticles (NPs) in a size range of 2-3 nm confined in a few-layered porous graphene nanomesh (PGN) framework driven by an electrochemical process. Raman spectra indicate that Co species preferentially anchor on the defective sites of the PGN, which results in markedly reduced irreversible Li storage and therefore significantly enhanced coulombic efficiency. The ultra-small Co 3 O 4 NPs provide a large surface area and a short solid-state diffusion length, which is propitious to achieving a high Li ion capacity at high rate. Also, the few-layered graphene network with high electronic conductivity not only permits easy access to the high surface area of the Co 3 O 4 NPs for the electrolyte ions, but also serves as a reservoir for high capacity Li storage. As a result, the Co 3 O 4 -PGN composite layers deliver an ultra-high capacity (1543 mA h g À1 at 150 mA g À1 ) and excellent rate capability (1075 mA h g À1 at 1000 mA g À1 ) with good cycling stability.

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