Efficient gel route to embed phosphorus into MOF-derived porous FePx as anodes for high performance lithium-ion batteries

Abstract

Rational design of phosphorus-rich materials with high P content and controllable microstructure is crucial for high-performance lithium ion batteries (LIBs). Herein, for the first time, a rapid MOFs-gel technique is skillfully employed for the facile and scalable synthesis of red phosphorus (red-P) nanoparticles inlaid Fe-benzenetricarboxylic (BTC) composite. During the subsequent phosphorization process, Fe-BTC was transformed into porous FePx, finally achieving a porous phosphorus-rich FePx@P composite with controllable amounts of red-P nanoparticles embedded in porous FePx matrix. Due to the unique structure and synergistic effect between components in the composite, the FePx@P composite with an optimized loading content of 61.2 wt% P exhibits excellent electrochemical performance for LIBs anodes (1283.9 mAh g−1 under 100 mA g−1 after 80 cycles and 418.2 mAh g−1 at 2 A g−1 after 1600 cycles). The abundant pores inside the FePx matrix can store sufficient electrolyte for fast ion transfer, as well as provide enough space for alleviating the volume change during charge/discharge process. The porous FePx matrix with much better conductivity wires up the inside red-P, facilitating charge transfer processes, while the controllable amounts of red-P nanoparticles with higher specific capacity can store more Li+ ions for higher energy storage. The skillful synthesis route is inspiring for the synthesis of other related materials for various fields.