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Research background B
•研究背景： 中空纳米结构对提升电池性能有巨大优势，
但传统方法难以制作 •研究目的：
提升锂硫电池容量；提高电池稳定性 •解决方案：
中空石墨烯纳米球壳结构，嵌入硫合成复 合材料，作为电池正极
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Abstract
•Hollow nanostructures：
and energy storage/conversion systems •Hollow nanocrystals：
mesoscale hollow structure, nanoscale quantum effects, and atomic-scale periodic arrangement •Hollow graphene nanoshells(HGNs)：
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Morphology and structure of HGNs
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Electrochemical performance of HGN-S
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Morphology of cycled HGN-S electrodes
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Conclusions
• HGNs通过介尺度催化自限性组装法合成，具有非常小的粒径、单层或 多层的石墨烯片层、3D分层的花瓣状相形态；
Li-S battery: poor cycling life and rate performance S: large volumetric expansion，poor conductivity Graphene: couldn’t integrate all the structural benefits. •The concept of HGNs might be a promising strategy, which yet calls for new synthetic methodology.
表面积大；活性部位充分暴露；物质输运的动力学性能优 良；表面通透性好
•A mesoscale approach to fabricate graphene shells:
催化剂作用下，在原位形成的纳米颗粒上实现纳米石墨烯 的自限性组装
•Use:
石墨烯纳米球壳作为基体与S复合，用作锂硫电池正极材 料
•Properties:
Results and Discussion
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The in situ catalytic self-limited assembly of HGNs
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Morphology and structure of α-Ni(OH)2DS
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Morphology and structure of HGNs
• Carbon source: dodecyl sulfate(DS) • 3D mesostructure: zero-dimensional (0D)
HGNs construct two-dimensional (2D) nanosheets and then assemble into a three-dimensional (3D) mesostructure 10
Hollow nanostructures新的合成方案
• A mesoscale catalytic self-limited assembly of hollow graphene spheres was proposed.
• Hard templates and working catalysts: in situ formed nickel-based NPs
• A template-involving top-down strategy：no catalytic capability to regularly manage the arrangement of carbon atoms；
• Thus, controllable synthesis of HGNs with an engineered hollow cavity, predetermined layer number, small size, and highly crystalline few-layer graphene shells is 9
文献汇报
硬膜板上催化作用下的自限性组装： 用在锂硫电池中的中尺度石墨烯纳米壳
汇报人：XXX
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目录

Source of the article
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Research background A
•Li-S batteriy: high theoretical energy density of 2600 Wh/kg;
初始放电容量：1520mAh/g(0.1C)
电流密度从0.1C提升至2.0C，70%容量保持
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Introduction
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Hollow nanostructures的优势
•Applications： catalysis, adsorption, chemical sensors, drug/gene delivery,
•S: naturally abundant, economically effective, and environmentally
friendly; •Graphene and other nanostructured carbon materials:
excellent conductivity, high specific surface area, accommodate large volume expansion; •Issues:
favourable electrical conductivity, good surface functionality, mechanical/chemical stability, and biocompatibility
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Hollow nanostructures的合成困 境
• The template-free or self-templating bottom-up approaches：hardly extended to HGN synthesis；