材料科学
硅
阳极
法拉第效率
纳米孔
电解质
扩散
电极
多孔硅
图层(电子)
化学工程
原子层沉积
复合材料
纳米技术
化学物理
光电子学
物理化学
热力学
化学
工程类
物理
作者
Jia‐Bin Fang,Yanqiang Cao,Shaozhong Chang,Fu‐Rui Teng,Di Wu,Aidong Li
标识
DOI:10.1002/adfm.202109682
摘要
Abstract The rapid and reversible lithiation/delithiation of silicon materials remains a challenging yet marvelous goal. Herein, harnessing the “nanoporous to compact” gradient design, a dual‐film consisting of flexible porous zincone and rigid compact TiO 2 (zincone/TiO 2 ) is controllably deposited onto a silicon electrode using molecular layer deposition and atomic layer deposition techniques. This dual‐film can tailor the stress and ionic diffusion kinetics for silicon anodes. That is, the elastic zincone acts as a buffer layer to dissipate inner stress through the deformation of pores, while the rigid TiO 2 (≈5 nm) provides silicon particles a satisfying mechanical strength and protects the silicon from engulfing by the solid electrolyte interphase. The density functional theory and galvanostatic intermittent titration technique results indicate the fast Li + diffusion kinetics in Si@zincone/TiO 2 electrode, resulting in a high initial Coulombic efficiency of 81.9% and an advantageous rate capability of 1224 mAh g −1 at 4 A g −1 . More importantly, a low capacity‐fading rate of only 0.051% per cycle can be achieved (discharge capacity of 753 mAh g −1 after 1000 cycles). Additionally, fractal theory verifies the Si@zincone/TiO 2 undergoes gentle reversible evolutions during cycling with a box fractal dimension ( D B ) of 1.73.
科研通智能强力驱动
Strongly Powered by AbleSci AI