A porous Co-Ru@C shell as a bifunctional catalyst for lithium oxygen batteries

作者:Chen, Xiang; Zhang, Xiuhui; Chen, Chunguang; Huang, Tao*; Yu, Aishui*
来源:RSC Advances, 2018, 8(42): 23973-23980.
DOI:10.1039/c8ra04144j

摘要

We use SiO2 as a template and dopamine as a carbon source to synthesize a hollow C shell, and we load Co and Ru nanoparticles onto it to obtain a Co-Ru@C shell composite. The diameter and thickness of the C shell are 100 nm and 5-10 nm, respectively, and numerous holes of different sizes exist on the C shell. Meanwhile, numerous C shells stack together to form macropores, thereby forming a hierarchical porous structure in the material. Brunauer-Emmett-Teller surface area analysis reveals that the specific surface area and pore volume of the Co-Ru@C shell are 631.57 m(2) g(-1) and 2.20 cc g(-1), respectively, which can result in many three-phase interfaces and provide more space for the deposition of discharge products. Compared with Co@C shell and C shell electrodes, the obtained Co-Ru@C shell-based electrodes exhibit the highest discharge capacity, the lowest oxygen reduction reaction/oxygen evolution reaction overpotential and the best cycle stability, indicating the excellent catalytic ability of the Co-Ru@C shell.

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