Materials Today Communications
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2024
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IF 3.7
Lingli Xu,Jingbo Chen,Jing Zhu,Tianxiang Li,Chaoyun Shi
Recently, SiO 2 has attracted increasing attention as an anode material for lithium-ion batteries (LIBs) owing to its low cost and high theoretical specific capacity. However, its inherent poor conductivity limits its practical application. To address this issue, nanostructured material design is considered an effective solution. Herein, based on the traditional ammonium tartrate template-directed sol-gel method, we use low-cost and easily available L-tartaric acid in place of D, L-tartaric acid to prepare high-yield silica nanotubes (SNTs) with a thin wall (ca. 50 nm), small diameter (ca. 150 nm), rough surface and open ends, as well as tiny spongy-like silica nanoparticles (SNPs) by adjusting the feeding amount and feeding mode of NH 4 OH solution. The electrochemical characterization results suggest that the SNTs show better cyclability and rate performance than the SNPs, which maintain a reversible capacity of 741.3 mAh g −1 after 500 cycles at a current density of 0.4 A g −1 and deliver a high rate capacity of 819.4 mAh g −1 at a high current rate of 2 A g −1 . The excellent electrochemical performance suggests that hollow one-dimensional hollow nanotubes are more efficient in improving the electrochemical performance of SiO 2 than zero-dimensional nanoparticles , and SNTs with thin tube walls and rough surfaces are demonstrated to be fascinating and promising anode materials for LIBs.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2024
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IF 9.4
Kefa Sheng,Hongyu Xia,Jianping Ge
Selective hydrogenation of nitroaromatics is a crucial industrial reaction, but there are still challenges in developing nanocatalysts with stable active centers, yet easily recyclable characteristics. Here, a magnetically separable Pd/Fe 3 O 4 @SiO 2 nanocatalyst was prepared through the seeding growth of silica on the Fe 3 O 4 nanocrystal cluster (NC) followed by in situ reduction of Pd nanoparticles (NPs) on the amino group modified Fe 3 O 4 @SiO 2 nannotube (NT). The nanocatalyst showed good activity and stability in the hydrogenation of a series of nitroaromatics as the Pd NPs were highly dispersed on the nanotubes. Meanwhile, it could be easily separated from the reaction solution and well-redispersed in the solvent for the next-round reaction due to the superparamagnetic property of the Fe 3 O 4 NC and the good dispersibility of silica in many organic solvents. The magnetically separable nanocatalyst combined the high activity of the nanocatalyst and the convenient separation of a traditional heterogeneous catalyst, which effectively promote the practical application of nanomaterials in catalysis.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Particuology
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2023
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IF 3.5
Zixu Shi,Chaoyun Shi,Huili Shi,Binfang He,Guoqiang Qin,Ao Li,Jing Zhu,Jingbo Chen
Silica-based anode material is the most concerned material at present, which has the advantages of good cycle stability, high theoretical specific capacity and abundant reserves. However, silica suffers from inherent low conductivity , severe volume expansion effect and low initial coulombic efficiency, which limits its application in lithium-ion batteries. Nanotubes structure can mitigate the volume expansion during lithiation/delithiation. In this article, silica nanotubes (SNTs) were prepared using carbon nanotubes (CNTs) as a template, and then the uniform carbon layer was coated on their surface by carbonization of citric acid . The hollow structure of nanotubes provides more sites for the insertion of Li + during lithiation and additional channels for Li + migration in the cycles, which improves the electrochemical performance. Conductivity can be enhanced by coating carbon layer. The specific capacity of the composite material is about 650 mAh g −1 at 0.1 A g −1 after 100 cycles. With a specific capacity of 400 mAh g −1 even at 1 A g −1 after 100 cycles. The silica-based material is a competitive anode material for lithium-ion batteries.
研究领域:
材料科学
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电化学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
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2021
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IF 6.901
Linqi Si,Kun Yan,Changle Li,Yanfang Huang,Xinchang Pang,Xiaomeng Yang,Dong Sui,Yongsheng Zhang,Jianshe Wang,Chunbao Charles Xu
Silica (SiO 2 ) with high specific capacity and low cost is a promising anode for lithium-ion batteries (LIBs), whereas its application is challenged by the substantial volume expansion and poor electrical conductivity. Phenolated and depolymerized lignin furfural (PDLF) resin as renewable carbon precursor, and hollow SiO 2 nanotubes are thus designed to address these challenges. Herein, we synthesize the free-standing SiO 2 nanotubes@carbon nanofibers (SNTs@CNFs) mat via electrospinning. From the nano-scale morphology, SNTs are embedded into the interior and surface of CNFs along with the fiber framework. The hollow and porous SiO 2 nanotubes relieve the volume expansion during the lithium-ion insertion/extraction. Meanwhile, the interconnected bio-based CNFs improve the electrical conductivity and shorten the lithium-ion diffusion path. The SNTs@CNFs mat exhibits excellent mechanical flexibility and is used as a free-standing anode without any binders, carbon black, and current collectors, it delivers an ultra-high reversible capacity of 1067 mAh g −1 at the current density of 100 mA g −1 after 300 cycles. Even at a high current density of 1000 mA g −1 , it remains a reversible capacity of 562 mAh g −1 after 700 cycles. This work marks an important exploration for next-generation high-energy density LIBs and other flexible energy storage devices.
研究领域:
材料科学
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能源存储
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纳米技术
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电化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）