Rare-Earth Metal–Organic Framework-Derived La<sub>2</sub>O<sub>3</sub>/Ni<sub><i>x</i></sub>P<sub><i>y</i></sub> Nanoparticles Embedded in Nitrogen-Doped Porous Carbon as Efficient Electrocatalysts for the Oxygen Evolution Reaction
Lifang Li, Hui Peng, Yumao Kang, Yaxin Hao, Fangqing Liu, Hongyuan Xin, Huichun Kang, Wei Wang, Ziqiang Lei
Abstract
Exploring non-noble metal electrocatalysts with high activity, elevated stability, and low cost is of great significance for efficient electrochemical energy storage and conversion technologies. Herein, rare-earth metal–organic framework (LaNi-MOF)-derived three-dimensional La 2 O 3 /Ni x P y nanoparticles embedded in nitrogen-doped porous carbon (La 2 O 3 /Ni x P y @NC) are rationally synthesized by a facile solvothermal method followed by pyrolysis and a low-temperature phosphating strategy. The highly conductive nitrogen-doped porous carbon and the synergistic effect between La 2 O 3 and Ni x P y nanoparticles provide abundant active catalytic sites and enhance the electron mass transfer capability, which endows the La 2 O 3 /Ni x P y @NC catalyst with excellent oxygen evolution reaction activity. Moreover, the La 2 O 3 /Ni x P y @NC catalyst provides a low overpotential (η 100 = 384 mV), which is superior to that of commercial RuO 2 (η 100 = 451 mV). More importantly, the introduction of La 2 O 3 can not only effectively adjust the electronic structure and morphology of the catalyst but also significantly improve the long-term stability and durability of the La 2 O 3 /Ni x P y @NC electrocatalyst. This work provides an efficient strategy for the future design of highly efficient catalysts enriched with rare-earth species.