当前位置：
X-MOL 学术
›
ACS Appl. Mater. Interfaces
›
论文详情
Our official English website, www.x-mol.net, welcomes your
feedback! (Note: you will need to create a separate account there.)
Boosting Conversion of the Si–O Bond by Introducing Fe2+ in Carbon-Coated SiOx for Superior Lithium Storage
ACS Applied Materials & Interfaces ( IF 8.3 ) Pub Date : 2024-07-22 , DOI: 10.1021/acsami.4c08687
Xiaozhong Zhou 1 , Xiaona An 1 , Lihua Ma 1 , Yan Zhang 1 , Nuoqian Yan 1 , Jiangwei Deng 1 , Hezong Peng 1 , Xiangyuan Li 1 , Ziqiang Lei 1
ACS Applied Materials & Interfaces ( IF 8.3 ) Pub Date : 2024-07-22 , DOI: 10.1021/acsami.4c08687
Xiaozhong Zhou 1 , Xiaona An 1 , Lihua Ma 1 , Yan Zhang 1 , Nuoqian Yan 1 , Jiangwei Deng 1 , Hezong Peng 1 , Xiangyuan Li 1 , Ziqiang Lei 1
Affiliation
|
SiOx-based anodes are of great promise for lithium-ion batteries due to their low working potential and high specific capacity. However, several issues involving large volume expansion during the lithiation process, low intrinsic conductivity, and unsatisfactory initial Coulombic efficiency (ICE) hinder their practical application. Here, an Fe–SiOx@C composite with significantly improved lithium-storage performance was successfully synthesized by combining Fe2+ modification with a carbon coating strategy. The results of both experiments and density functional theory calculations confirm that the Fe2+ modification not only effectively achieves uniform carbon coating but also weakens the bonding energy of the Si–O bond and boosts reversible lithiation/delithiation reactions, resulting in great improvement in the electrical conductivity, ICE, and reversible specific capacity of the as-obtained Fe–SiOx@C. Together with the coated carbon, the in situ-generated conductive Fe-based intermediates also ensure the electrical contact of active components, relieve the volume expansion, and maintain the structural integrity of the electrode during cycling. And the Fe–SiOx@C (x ≈ 1.5) electrode can deliver a high-rate capacity of 354 mA h g–1 at 2.0 A g–1 and long-term cycling stability (552.4 mA h g–1 at 0.5 A g–1 even after 500 cycles). The findings here provide a facile modification strategy to improve the electrochemical lithium-storage performance of SiOx-based anodes.
中文翻译：
通过在碳包覆的 SiOx 中引入 Fe2+ 来促进 Si-O 键的转化，以实现卓越的锂存储
SiO x基负极由于其低工作电位和高比容量而在锂离子电池中具有广阔的前景。然而，锂化过程中体积膨胀大、本征电导率低和初始库仑效率（ICE）不理想等问题阻碍了其实际应用。在此，通过将Fe 2+改性与碳涂层策略相结合，成功合成了具有显着改善的锂存储性能的Fe-SiO x @C复合材料。实验和密度泛函理论计算结果证实，Fe 2+改性不仅有效实现了均匀的碳包覆，而且削弱了Si-O键的键能，促进了可逆的锂化/脱锂反应，从而使性能得到了很大的提高。所得 Fe-SiO x @C 的电导率、ICE 和可逆比容量。与涂层碳一起，原位生成的导电铁基中间体还确保活性成分的电接触，缓解体积膨胀，并在循环过程中保持电极的结构完整性。 Fe-SiO x @C ( x ≈ 1.5) 电极可在 2.0 A g –1下提供 354 mA hg –1的高倍率容量和长期循环稳定性（在 0.5 A g –1 下为 552.4 mA hg –1 ） 1即使在 500 个周期后）。本文的研究结果提供了一种简便的改性策略，以提高 SiO x基阳极的电化学储锂性能。
更新日期：2024-07-22
中文翻译：
通过在碳包覆的 SiOx 中引入 Fe2+ 来促进 Si-O 键的转化，以实现卓越的锂存储
SiO x基负极由于其低工作电位和高比容量而在锂离子电池中具有广阔的前景。然而，锂化过程中体积膨胀大、本征电导率低和初始库仑效率（ICE）不理想等问题阻碍了其实际应用。在此，通过将Fe 2+改性与碳涂层策略相结合，成功合成了具有显着改善的锂存储性能的Fe-SiO x @C复合材料。实验和密度泛函理论计算结果证实，Fe 2+改性不仅有效实现了均匀的碳包覆，而且削弱了Si-O键的键能，促进了可逆的锂化/脱锂反应，从而使性能得到了很大的提高。所得 Fe-SiO x @C 的电导率、ICE 和可逆比容量。与涂层碳一起，原位生成的导电铁基中间体还确保活性成分的电接触，缓解体积膨胀，并在循环过程中保持电极的结构完整性。 Fe-SiO x @C ( x ≈ 1.5) 电极可在 2.0 A g –1下提供 354 mA hg –1的高倍率容量和长期循环稳定性（在 0.5 A g –1 下为 552.4 mA hg –1 ） 1即使在 500 个周期后）。本文的研究结果提供了一种简便的改性策略，以提高 SiO x基阳极的电化学储锂性能。
京公网安备 11010802027423号