Multivalent cation substitution boosted sodium-ion storage in NASICON-type iron-phospho-sulphate cathodes

IF 13.3 1区工程技术 Q1 ENGINEERING, CHEMICAL

Chemical Engineering Journal Pub Date : 2024-11-23 DOI:10.1016/j.cej.2024.157979

Sharad Dnyanu Pinjari, Ravi Chandra Dutta, Saikumar Parshanaboina, Purandas Mudavath, Subhajit Singha, Deepak Dubal, Xijue Wang, John Bell, Ashok Kumar Nanjundan, Rohit Ranganathan Gaddam

{"title":"Multivalent cation substitution boosted sodium-ion storage in NASICON-type iron-phospho-sulphate cathodes","authors":"Sharad Dnyanu Pinjari, Ravi Chandra Dutta, Saikumar Parshanaboina, Purandas Mudavath, Subhajit Singha, Deepak Dubal, Xijue Wang, John Bell, Ashok Kumar Nanjundan, Rohit Ranganathan Gaddam","doi":"10.1016/j.cej.2024.157979","DOIUrl":null,"url":null,"abstract":"Despite advancements in NASICON cathodes, their widespread use in sodium-ion batteries (NIBs) remains limited due to low energy density, durability issues, and the use of scarce transition metals like vanadium. While the NASICON-type NaFe2(PO4)(SO4)2 cathode shows potential in addressing these challenges, it encounters issues with electron transport and Na+ diffusion. To overcome these hurdles, we introduce a novel Al3+-substituted NaFe2(PO4)(SO4)2 (NFAPS) cathode in this study, synthesised by a straightforward solid-state ball-milling method. Herein, Al3+ is strategically incorporated at the Fe site, and MWCNT is added in situ during NFAPS synthesis. The doping reduces the band gap, improves charge mobility, and maintains structural integrity during the Na+ insertion and extraction processes. Further, Al3+ enhances the spin state of Fe by attenuating the energy gap of undoped NFAPS cathodes, resulting in improved electrochemical performance, as evidenced by temperature-dependent magnetization susceptibility (M−T) and electron paramagnetic resonance (EPR) measurements. The optimized cathode, NaFe1.93Al0.07(PO4)(SO4)2 (NFAPS07) delivered a high specific discharge capacity of 124 mAh/g at C/20 (1C = 127 mAh/g), impressive rate capability (93.49 mAh/g at C/5 and 78.85 mAh/g at C/2) and good cycle life even at higher current rates. Ex-situ XRD analysis of NFAPS electrodes at various (de)sodiation voltages shows negligible volume expansion with minimal structural distortion. Further, NFAPS07 exhibits the highest reported energy density of 372 Wh kg−1 among all NASICON-based NaFe2(PO4)(SO4)2 cathode. Both experimental and first-principles studies confirm that enhanced charge migration, electrical conductivity, and lower activation barrier stem from synergistic effects of optimised Al3+ doping in NFAPS. Such multivalent cation-doped NASICONs can be adapted to economically design next-generation high-energy–density NIB.","PeriodicalId":270,"journal":{"name":"Chemical Engineering Journal","volume":"9 1","pages":""},"PeriodicalIF":13.3000,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chemical Engineering Journal","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1016/j.cej.2024.157979","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, CHEMICAL","Score":null,"Total":0}

引用次数: 0

Abstract

Despite advancements in NASICON cathodes, their widespread use in sodium-ion batteries (NIBs) remains limited due to low energy density, durability issues, and the use of scarce transition metals like vanadium. While the NASICON-type NaFe₂(PO₄)(SO₄)₂ cathode shows potential in addressing these challenges, it encounters issues with electron transport and Na⁺ diffusion. To overcome these hurdles, we introduce a novel Al³⁺-substituted NaFe₂(PO₄)(SO₄)₂ (NFAPS) cathode in this study, synthesised by a straightforward solid-state ball-milling method. Herein, Al³⁺ is strategically incorporated at the Fe site, and MWCNT is added in situ during NFAPS synthesis. The doping reduces the band gap, improves charge mobility, and maintains structural integrity during the Na⁺ insertion and extraction processes. Further, Al³⁺ enhances the spin state of Fe by attenuating the energy gap of undoped NFAPS cathodes, resulting in improved electrochemical performance, as evidenced by temperature-dependent magnetization susceptibility (M−T) and electron paramagnetic resonance (EPR) measurements. The optimized cathode, NaFe_1.93Al_0.07(PO₄)(SO₄)₂ (NFAPS07) delivered a high specific discharge capacity of 124 mAh/g at C/20 (1C = 127 mAh/g), impressive rate capability (93.49 mAh/g at C/5 and 78.85 mAh/g at C/2) and good cycle life even at higher current rates. Ex-situ XRD analysis of NFAPS electrodes at various (de)sodiation voltages shows negligible volume expansion with minimal structural distortion. Further, NFAPS07 exhibits the highest reported energy density of 372 Wh kg⁻¹ among all NASICON-based NaFe₂(PO₄)(SO₄)₂ cathode. Both experimental and first-principles studies confirm that enhanced charge migration, electrical conductivity, and lower activation barrier stem from synergistic effects of optimised Al³⁺ doping in NFAPS. Such multivalent cation-doped NASICONs can be adapted to economically design next-generation high-energy–density NIB.

Abstract Image

查看原文本刊更多论文

多价阳离子置换促进了 NASICON 型硫酸铁磷阴极中的钠离子储存

尽管 NASICON 阴极取得了进步，但由于能量密度低、耐久性问题以及使用了稀缺的过渡金属（如钒），其在钠离子电池（NIB）中的广泛应用仍然受到限制。虽然 NASICON 型 NaFe2(PO4)(SO4)2阴极在应对这些挑战方面显示出潜力，但它在电子传输和 Na+ 扩散方面遇到了问题。为了克服这些障碍，我们在本研究中引入了一种新型 Al3+ 取代的 NaFe2(PO4)(SO4)2（NFAPS）阴极，它是通过一种简单的固态球磨法合成的。在 NFAPS 合成过程中，Al3+ 被策略性地掺入铁位点，MWCNT 被原位添加。这种掺杂降低了带隙，提高了电荷迁移率，并在 Na+ 插入和提取过程中保持了结构的完整性。此外，Al3+ 还通过减弱未掺杂 NFAPS 阴极的能隙来增强铁的自旋态，从而改善了电化学性能，这一点可以通过随温度变化的磁化率（M-T）和电子顺磁共振（EPR）测量得到证明。优化后的阴极 NaFe1.93Al0.07(PO4)(SO4)2 (NFAPS07) 在 C/20 条件下具有 124 mAh/g 的高比放电容量（1C = 127 mAh/g），令人印象深刻的速率能力（C/5 条件下为 93.49 mAh/g，C/2 条件下为 78.85 mAh/g），即使在更高的电流速率下也具有良好的循环寿命。在不同（去）钠化电压下对 NFAPS 电极进行的原位 XRD 分析表明，其体积膨胀可忽略不计，结构变形极小。此外，在所有基于 NASICON 的 NaFe2(PO4)(SO4)2 阴极中，NFAPS07 的能量密度最高，达到 372 Wh kg-1。实验和第一原理研究都证实，NFAPS 中优化的 Al3+ 掺杂产生了协同效应，从而增强了电荷迁移、电导率并降低了活化势垒。这种多价阳离子掺杂的 NASICON 可用于经济地设计下一代高能量密度 NIB。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Chemical Engineering Journal 工程技术-工程：化工

CiteScore

21.70

自引率

9.30%

发文量

6781

审稿时长

2.4 months

期刊介绍： The Chemical Engineering Journal is an international research journal that invites contributions of original and novel fundamental research. It aims to provide an international platform for presenting original fundamental research, interpretative reviews, and discussions on new developments in chemical engineering. The journal welcomes papers that describe novel theory and its practical application, as well as those that demonstrate the transfer of techniques from other disciplines. It also welcomes reports on carefully conducted experimental work that is soundly interpreted. The main focus of the journal is on original and rigorous research results that have broad significance. The Catalysis section within the Chemical Engineering Journal focuses specifically on Experimental and Theoretical studies in the fields of heterogeneous catalysis, molecular catalysis, and biocatalysis. These studies have industrial impact on various sectors such as chemicals, energy, materials, foods, healthcare, and environmental protection.