Nickel and manganese oxide heterostructure nanoparticles supported by carbon nanotube for highly efficient oxygen evolution reaction catalysis

Heterostructures have been shown to play a key role in promoting electrocatalysis. However, it is still a challenge to design and prepare multi metals heterostructure catalyst with high performance. In this paper, a simple and efficient preparation method was used to anchor Ni-x vertical bar Mn1-xO heterostructure nanoparticles on CNTs with oxygen defect sites. The treated CNT were used to provide stable anchor sites for metal ions, and effectively induced the production of highly fused Ni-x vertical bar Mn1-xO nanoparticles with atomic-level heterogeneous interfaces. The Ni-0.95 vertical bar Mn0.05O/CNT catalyst shows a nice oxygen evolution reaction performance. At a current density of 10 mA cm -2 , the overpotential is only 293 mV, and the Tafel slope is 55.6 mV dec(-1), which is much better than that of Ni/CNT and MnO/CNT catalyst under the same conditions. According to the experimental result and density functional theory calculation, it is suggested that the proportion of heterogeneous metal elements, the phase composition at the heterogeneous interface, the heterostructure size and the heterostructure carrier will affect the oxygen evolution catalyst performance. This work is benefit for the design of cheap and high-performance catalyst with multi metal heterogeneous interfaces.