Facile fabrication of a nanoporous silicon electrode with superior stability for lithium ion batteries

In this paper, we demonstrate that a novel silicon electrode with a large amount of nanopores can be fabricated by an in-situ thermal generating approach using triethanolamine as a sacrificing template. The fabrication process is simple, green, low cost, and easy to be scaled up. This electrode achieves high reversible capacities (2500 mAh g^-1) with excellent cycling stability (∼90% capacity retention after 100 charge-discharge cycles), showing great potential as a high-performance anode for lithium-ion batteries. It is revealed that the high void volume with pore size of <200 nm can both enlarge the interface between active silicon particles and the electrolyte, and accommodate the severe volume change of silicon, thus leading to remarkably improved reversible capacity and cycling stability. The design concept and the fabrication approach used in the nanoporous silicon electrode may also be extended to other electrodes for electrochemical applications.