Jiawei Li, Junren Xiang, Ge Yi, Zhijia Hu, Xiao Liu and Rong Chen
{"title":"Stabilization of the surface and lattice structure for LiNi0.83Co0.12Mn0.05O2via B2O3 atomic layer deposition and post-annealing†","authors":"Jiawei Li, Junren Xiang, Ge Yi, Zhijia Hu, Xiao Liu and Rong Chen","doi":"10.1039/D4YA00206G","DOIUrl":null,"url":null,"abstract":"<p >The Ni-rich LiNi<small><sub><em>x</em></sub></small>Co<small><sub><em>y</em></sub></small>Mn<small><sub>1−<em>x</em>−<em>y</em></sub></small>O<small><sub>2</sub></small> cathode (<em>x</em> ≥ 0.6) shows weak rate capability due to its deleterious surface lithium impurities and lattice defects. Herein, uniform ultrathin B<small><sub>2</sub></small>O<small><sub>3</sub></small> coatings built by atomic layer deposition (ALD) are utilized to construct a B<small><sup>3+</sup></small> doped single-crystal LiNi<small><sub>0.83</sub></small>Co<small><sub>0.12</sub></small>Mn<small><sub>0.05</sub></small>O<small><sub>2</sub></small> (SC83) <em>via</em> post-annealing. LiOH is consumed due to reacting with B<small><sub>2</sub></small>O<small><sub>3</sub></small> during the B<small><sub>2</sub></small>O<small><sub>3</sub></small> ALD process, and then B<small><sub>2</sub></small>O<small><sub>3</sub></small> is transformed into B<small><sup>3+</sup></small> doping accompanied by the reduction of Li<small><sub>2</sub></small>CO<small><sub>3</sub></small> during the post-annealing. Surface and bulk characterization results show that B<small><sup>3+</sup></small> tends to diffuse into the bulk of the SC83 during the post-annealing, which expands the <em>a</em> and <em>c</em> axes and reduces the Li<small><sup>+</sup></small>/Ni<small><sup>2+</sup></small> mixing of the SC83. When the B<small><sup>3+</sup></small> content exceeds 0.54 wt%, B<small><sup>3+</sup></small> segregation occurs on the surface of the SC83, which decreases the electronic conductivity of the SC83. B<small><sup>3+</sup></small> doping at the content of 0.54 wt% gives the highest capacity of 177.6 mA h g<small><sup>−1</sup></small> at 1C rate. The B<small><sub>2</sub></small>O<small><sub>3</sub></small> ALD coupled with post-annealing builds a highly electronic and Li<small><sup>+</sup></small> conductive surface and bulk for the SC83, which is the key to the improvement of the rate capability.</p>","PeriodicalId":72913,"journal":{"name":"Energy advances","volume":" 7","pages":" 1688-1696"},"PeriodicalIF":3.2000,"publicationDate":"2024-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/ya/d4ya00206g?page=search","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Energy advances","FirstCategoryId":"1085","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2024/ya/d4ya00206g","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
The Ni-rich LiNixCoyMn1−x−yO2 cathode (x ≥ 0.6) shows weak rate capability due to its deleterious surface lithium impurities and lattice defects. Herein, uniform ultrathin B2O3 coatings built by atomic layer deposition (ALD) are utilized to construct a B3+ doped single-crystal LiNi0.83Co0.12Mn0.05O2 (SC83) via post-annealing. LiOH is consumed due to reacting with B2O3 during the B2O3 ALD process, and then B2O3 is transformed into B3+ doping accompanied by the reduction of Li2CO3 during the post-annealing. Surface and bulk characterization results show that B3+ tends to diffuse into the bulk of the SC83 during the post-annealing, which expands the a and c axes and reduces the Li+/Ni2+ mixing of the SC83. When the B3+ content exceeds 0.54 wt%, B3+ segregation occurs on the surface of the SC83, which decreases the electronic conductivity of the SC83. B3+ doping at the content of 0.54 wt% gives the highest capacity of 177.6 mA h g−1 at 1C rate. The B2O3 ALD coupled with post-annealing builds a highly electronic and Li+ conductive surface and bulk for the SC83, which is the key to the improvement of the rate capability.