Dual‐Design of Nanoporous to Compact Interface via Atomic/Molecular Layer Deposition Enabling a Long‐Life Silicon Anode

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.

Atomic/Molecular Layer Deposition for Designer's Functional Metal–Organic Materials

“…Diethylzinc is the most common precursor for zinc in the ALD/MLD processes; it is often combined with HQ, [54,55,66,107,133,230,[244][245][246][247]250,361,366,[370][371][372][373][374][375][376][377][378] but also with many other organic components. [46,48,115,134,211,212,226,228,233,238,239,241,265,272,278,324,345,349,[379][380][381][382][383][384][385][386][387][388]…”

“…[117,229] For titanium, the most common precursor is TiCl 4 , extensively used with EG, [179,293,[391][392][393][394][395][396][397][398][399][400] and other orga nics. [46,49,105,112,122,211,230,232,235,248,254,255,336,378,390,[401][402][403][404][405][406][407][408] For example, the combination, TiCl 4 plus maleic anhydride has been utilized to deposit thin films with biologic synaptic functions. [401] Besides the TiCl 4 precursor, also titanium tetra-isopropoxide [45,135,136,210,217,227,265,351,409] and tetrakis(dimethylamido) titanium [112] precursors have be...…”

“…Diethylzinc is the most common precursor for zinc in the ALD/MLD processes; it is often combined with HQ, [ 54,55,66,107,133,230,244–247,250,361,366,370–378 ] but also with many other organic components. [ 46,48,115,134,211,212,226,228,233,238, 239,241,265,272,278,324,345,349,379–390 ] The DEZ + HQ process has been widely utilized for the growth of different superlattice structures in which the Zn–HQ layers are combined with thicker ZnO layers grown with ALD cycles from DEZ plus H 2 O.…”

Fe/Fe3C modification to effectively achieve high-performance Si–C anode materials

“…Research shows that adding some non-carbon materials, such as the metal oxides (ZnO, 21,22 Al 2 O 3 , 23,24 and TiO 2 (ref. 25 and 26)), metal nitrides (TiN (ref. 27 and 28)), metal carbides (Fe 3 C (ref.…”

Accommodation of Two-Dimensional SiOx in a Point-to-Plane Conductive Network Composed of Graphene and Nitrogen-Doped Carbon for Robust Lithium Storage

“…As one of the most successful energy-storage devices, lithium-ion batteries (LIBs) have been widely applied in various portable electronics and electric vehicles. − Among the emerging anode materials for LIBs, silicon-based materials have been regarded as the most promising alternative candidate owing to their ultrahigh theoretical capacity (4200 mA h g –1 ), low working potential (around 0.2–0.3 V versus Li/Li + ), and richness in the earth’s crust. , Unfortunately, the drastic volume change (above 300%) during the alloying and dealloying process may cause cracking, structural destruction of the electrodes, and electrical contact loss . Additionally, the low ionic and electronic conductivities also hinder the commercialization of silicon-based anodes. − …”