Atomic layer deposited V2O5 coatings: a promising cathode for Li-ion batteries

Abstract

<p><span lang="EN-US">A modified, thermal atomic layer deposition process was employed for the pulsed chemical vapor deposition growth of vanadium pentoxide films using </span><span lang="EN-GB">t</span><span lang="EN-US">etrakis (dimethylamino) vanadium and water as a co-reagent.</span><span lang="EN-GB">Depositions were carried out at 350<sup>o</sup></span><span lang="EN-US">C for 400 pulsed CVD cycles, and samples were subsequently annealed for 1hour at 400<sup>°</sup>C in air to form materials with enhanced cycling stability during the continuous lithium-ion intercala­tion/deintercalation processes. The diffusion coefficient was estimated to be 2.04x10<sup>-10</sup> and 4.10x10<sup>-10</sup> cm<sup>2</sup> s<sup>-1</sup> for the cathodic and anodic processes, respectively. These values are comparable or lower than those reported in the literature, indicating the capability of Li<sup>+</sup> of getting access into the vanadium pentoxide framework at a fast rate. Overall, it presents a specific discharge capacity of 280 mAh g<sup>-1</sup>, capacity retention of 75 % after 10000 scans, a coulombic efficiency of 100 % for the first scan, dropping to 85 % for the 10000<sup>th</sup> scan, and specific energy of 523 Wh g<sup>-1</sup>.</span></p>