The conversion of methane to more valuable chemicals is one of the most intensively studied topics in catalysis. The direct conversion of methane is attractive because the process is simple, but unfortunately its products are chemicals that are more reactive than methane. The current status of this research field is discussed with an emphasis on C-H bond activation and future challenges.

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Nitrogen-doped graphene treated with ammonia under different temperatures was used as the catalysts for the epoxidation of trans-stilbene and styrene at 373 K. NG-800 (N-doped graphene treated at 800 °C for 8 h) performed the best and gave the highest recyclable catalytic activity for the epoxidation of trans-stilbene, with 95.8% conversion and 94.4% selectivity to trans-stilbene epoxide. The catalytic center has been identified with the reaction mechanism elucidated by DFT calculation.

Through the adsorption/intercalation of cobalt phthalocyanine (CoPc) onto/ into graphene oxide (GO) layers, CoPc−GO nanocomposite was prepared via a simple solvent evaporation method driven by the electronic interaction between CoPc and GO. The interaction between GO and CoPc has been studied in detail by various methods. The result suggests that the interaction does not follow a simple donor−acceptor mode, but, instead, it is complicated two-way process including the transfer of electron from the graphitic domain to the adsorbed/intercalated CoPc, and a feedback from the Co ions through the ligand-like attacking of oxygen functional groups of GO to the central cobalt ions. The obtained structural hybrid materials have potential in the electrochemical detection of the compounded medicine.

Monodispersed bimetallic PdAg nanoparticles can be fabricated through the emulsion-assisted ethylene glycol (EG) ternary system. Different compositions of bimetallic PdAg nanoparticles, Pd80Ag20, Pd65Ag35 and Pd46Ag54 can be obtained via adjusting the reaction parameters. For the formation process of the bimetallic PdAg nanoparticles, there have two-stage growth processes: firstly, nucleation and growth of the primary nanoclusters; secondly, formation of the secondary nanoparticles with the size-selection and relax process via the coalescence or aggregation of the primary nanoclusters. The as-prepared PdAg can be supported on the carbon black without any post-treatment, which exhibited high electro-oxidation activity towards methanol oxidation under alkaline media. More importantly, carbon-supported Pd80Ag20 nanoparticles reveal distinctly superior activities for the methanol oxidation, even if compared with commercial Pt/C electro-catalyst. It is concluded that the enhanced activity is dependant on the unique twinning structure with heterogeneous phase due to the dominating coalescence growth in EG ternary system.

A heterogeneous, inexpensive, and environmentally friendly graphene oxide catalytic system for the C-H bond arylation of benzene enables the formation of biaryl compounds in the presence of aryl iodides. The oxygen functional groups in these graphene oxide sheets and the addition of KOtBu are essential for the observed catalytic activity. Reactions with various model compounds and DFT calculations confirmed that these negatively charged oxygen atoms promote the overall transformation by stabilizing and activating K(+) ions, which in turns facilitates the activation of the C-I bond. However, the graphene π system also greatly facilitates the overall reaction as the aromatic coupling partners are easily adsorbed.

A facile one-pot approach is successfully developed to construct the stable Au nanochains with silica shell via self-assembly and classical Stöber process. The resulting Au chain@SiO2 nanoparticles holds great promise for serving as a safe, reusable, and high-performance photothermal agent against cancer.