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In this paper, we report the construction of network-like platinum (Pt) nanosheets based on Pt/reduced graphite oxide (Pt/rGO) hybrids by delicately utilizing a calorific-effect-induced-fusion strategy. The tiny Pt species first catalyzed the H2-O2 combination reaction. The released heat triggered the combustion of the rGO substrate under the assistance of the Pt species catalysis, which induced the fusion of the tiny Pt species into a network-like nanosheet structure. The loading amount and dispersity of Pt on rGO are found to be crucial for the successful construction of network-like Pt nanosheets. The as-prepared products present excellent catalytic hydrogenation activity and superior stability towards unsaturated bonds such as olefins and nitrobenzene. The styrene can be completely converted into phenylethane within 60 min. The turnover frequency (TOF) value of network-like Pt nanosheets is as high as 158.14 h−1, which is three times higher than that of the home-made Pt nanoparticles and among the highest value of the support-free bimetallic catalysts ever reported under similar conditions. Furthermore, the well dispersibility and excellent aggregation resistance of the network-like structure endows the catalyst with excellent recyclability. The decline of conversion could be hardly identified after five times recycling experiments.

The composition and morphology evolution for PtxNi1−x (0 < x < 1) nanoalloys was achieved by adjusting the growth kinetics, which were found different under different temperatures. The structure-dependent electrocatalytic performance was evaluated with MOR as the model reaction.

Quasi-concave Pt-Ni alloy nanostructures were synthesized via a solvothermal method, and were thought to form by epitaxial growth on the 12 vertexes of a cuboctahedron. A simultaneous etchingovergrowth process was proposed to illustrate the growth mechanism. The epitaxial layer was of different composition from the core, as confirmed by high-resolution transmission electron microscopy, selectedarea electron diffraction and powder X-ray diffraction characterizations. The concave structures exhibited high catalytic activity towards methanol oxidation. The mass-normalized catalytic activity of the concave products was~3 times that of pure Pt nanoparticles synthesized under similar conditions, and 13.6 times that of commercial Pt/C. X-ray photoelectron spectroscopy characterization indicated that the binding energy of the concave structures shifted to lower energy, relative to the pure Pt. The modified electronic structure by introducing Ni was thought to be responsible for the enhanced catalytic activity.

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