Green, Template-Less Synthesis of Honeycomb-like Porous Micron-Sized Red Phosphorus for High-Performance Lithium Storage

Large-volume-expansion-induced material pulverization severely limits the electrochemical performance of high-capacity red phosphorus (RP) in alkali-ion batteries. Honeycomb-like porous materials can effectively solve the issues due to their abundant interconnected pore structures. Nevertheless, it is difficult and greatly challenging to fabricate a honeycomb-like porous RP that has not yet been fabricated via chemical synthesis. Herein, we successfully fabricate a honeycomb-like porous micron-sized red phosphorus (HPRP) with a controlled pore structure via a large-scale green and template-less hydrothermal strategy. It is demonstrated that dissolved oxygen in the solution can accelerate the destruction of P9 cages of RP, thus forming abundant active defects with a faster reaction rate, so the fast corrosion forms the honeycomb-like porous structure. Owing to the free volume, interconnected porous structure, and strong robustness, the optimized HPRP-36 can mitigate drastic volume variation and prevent pulverization during cycling resulting in tiny particle-level outward expansion, demonstrated by in situ TEM and ex situ SEM analysis. Thus, the HPRP-36 anode delivers a large reversible capacity (2587.4 mAh g(-1) at 0.05 A g(-1)) and long-cycling stability with over 500 cycles (similar to 81.9% capacity retention at 0.5 A g(-1)) in lithium-ion batteries. This generally scalable, green strategy and deep insights provide a good entry point in designing honeycomb-like porous micron-sized materials for high-performance electrochemical energy storage and conversion.

Automated summary

A controlled pore structure honeycomb-like porous micron-sized red phosphorus (HPRP) was successfully fabricated using a large-scale green and template-less hydrothermal strategy, with dissolved oxygen in the solution accelerating the destruction of P9 cages of RP resulting in abundant active defects and formation of the porous structure. The optimized HPRP-36 anode exhibited large reversible capacity and long-cycling stability in lithium-ion batteries, showcasing potential for high-performance electrochemical energy storage applications.