With the rapid consumption of non-renewable energy and the emergence of many environmental pollution problems, the human demand for "green" energy is even more pressing. As one of many "green" energy sources, direct methanol fuel cells (DMFCs) convert the chemical energy of methanol and oxidizer directly into electricity. Due to its low fuel cost, simple structure, high energy density and conversion efficiency, and almost zero pollution, the fuel cell attracts the attention of many researchers. At present, most of the electrode catalysts used in direct methanol fuel cells are platinum-based catalysts. However, this catalyst has high preparation cost, poor catalytic activity and stability, and seriously hinders the commercialization of DMFC. Therefore, the synthesis of a high catalytic activity and cheaper platinum-based composite catalyst DMFC development of great significance.

Recently, solid-based researchers developed a simple and "green" synthetic method for the preparation of Pt / rGO nanocomposites based on Laser ablation in liquids (LAL) technology. Figure 1 (a) shows a schematic of the synthesis of this composite material. LAL-induced high activity MnOx particles can be uniformly loaded on the GO nanopaticles to form MnOx / rGO nanocomposites. The highly active MnOx particles can not only restore PtCl62? And GO simultaneously as a reducing agent, but also fix the reduced ultrafine Pt nanoparticles in situ as a sacrificial template. The resulting Pt nanoparticles have a size of about 1.8 nm (Figure 1b and c) and are uniformly distributed on the rGO nanosheet.

Compared with commercial Pt / C catalysts, this Pt / rGO catalyst showed higher catalytic activity for methanol oxidation (Fig. 1d and e) and stability (Fig. 1f and g). The above results show that the synthesized Pt / rGO catalyst has potential applications in the DMFC, and the synthesis method for the future synthesis of precious metal / graphene nanocomposites provides a new way of thinking.

Relevant work has been published on ACS Appl. Mater. Interfaces (ACS Appl. Mater. Interfaces 2015, 7, 22935? 22940). The research has been supported by the National Key Basic Research and Development Program (No. 2014CB931704) and the National Natural Science Foundation of China.

Figure 1. Pt / rGO catalyst: (a) Schematic diagram of synthesis; (b and c) TEM image and particle size distribution histogram of Pt nanoparticles; (d and e) and commercial Pt / C catalyst in acidic and basic media (F and g) and commercial Pt / C catalyst in acidic and alkaline media, the catalytic stability of the comparison results.

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