Prussian blue(PB) was used as catalyst to improve the extent of graphitization of polyacrylonitrile(PAN)-based carbon fibers.PB was deposited on carbon fibers by anodic electrodeposition and the thickness of PB coatin...Prussian blue(PB) was used as catalyst to improve the extent of graphitization of polyacrylonitrile(PAN)-based carbon fibers.PB was deposited on carbon fibers by anodic electrodeposition and the thickness of PB coating(PB content) was controlled by adjusting the electrodeposition time.PAN-based carbon fibers with PB coating were heat-treated and the extent of graphitization was measured by X-ray diffractometry and Raman spectroscopy.The results indicate that the extent of graphitization of PAN-based carbon fibers is enhanced in the presence of the coating.When the PB-coated carbon fibers were heat-treated at 1 900 ℃,interlayer spacing(d002) and crystallite size(Lc) reach 0.336 8 and 21.2 nm respectively.Contrarily,the values of d002 and Lc are 0.341 4 and 7.4 nm respectively when the bare carbon fibers were heat-treated at 2 800 ℃.Compared with the bare carbon fibers,PB can make the heat treatment temperature(HTT) drop more than 500 ℃ in order to reach the same extent of graphitization.Furthermore,the research results show that PB content also has a certain influence on the extent of graphitization at the same HTT.展开更多
普鲁士蓝及其类似化合物(Prussian blue analogous,PBAs)因其固有的热力学稳定性、宽广的离子插层/脱嵌通道、丰富的电化学活性位点以及可调节的化学组成与元素比例,已经成为下一代钠离子电池正极材料的有力候选者。然而,这类材料的电...普鲁士蓝及其类似化合物(Prussian blue analogous,PBAs)因其固有的热力学稳定性、宽广的离子插层/脱嵌通道、丰富的电化学活性位点以及可调节的化学组成与元素比例,已经成为下一代钠离子电池正极材料的有力候选者。然而,这类材料的电化学性能常常受到晶体缺陷和高含量结晶水及间隙水的影响。本文论述了PBAs的结构,并从单电子和双电子的角度概括了其分类,探讨了当前这类材料面临的挑战,并从结晶度控制、缺陷控制、形貌调控、离子掺杂/取代、组分优化以及碳包覆/复合六个方面系统地综述了现有的典型改性策略,评述了这类材料从实验室研究向产业化应用过渡的现状。此外,本文还展望了PBAs在钠离子电池领域的发展前景,通过材料工程和表面科学的进步,PBAs有望从实验室阶段迈向工业化应用。展开更多
目的验证普鲁士蓝纳米颗粒(Prussian blue nanoparticles,PBNPs)体内外调控C2C12细胞抗氧化和改善线粒体功能的能力及改善衰老性肌萎缩的效能。方法制备PBNPs并进行表征。体外实验:检测PBNPs分解H_(2)O_(2)和·O_(2)^(-)的能力和生...目的验证普鲁士蓝纳米颗粒(Prussian blue nanoparticles,PBNPs)体内外调控C2C12细胞抗氧化和改善线粒体功能的能力及改善衰老性肌萎缩的效能。方法制备PBNPs并进行表征。体外实验:检测PBNPs分解H_(2)O_(2)和·O_(2)^(-)的能力和生物相容性;在H_(2)O_(2)条件下,检测PBNPs对C2C12细胞的保护作用、活性氧荧光表达及线粒体功能。体内实验:小鼠腹腔注射D-半乳糖(D-galactose,D-gal)建立衰老性肌萎缩的模型,分对照组(未予治疗)、D-gal组及D-gal+PBNPs干预组,观察体质量和组织形态学变化。结果体外实验:PBNPs在25~100μg/mL质量浓度下对细胞无毒性;PBNPs对H_(2)O_(2)有降解活性且有很强的清除超氧阴离子自由基的能力;线粒体膜电位提示PBNPs可有效改善氧化应激条件下膜电位的下降及维持细胞内的三磷酸腺苷(adenosine triphosphate,ATP)含量。Western blot实验结果提示PBNPs干预后可显著提高C2C12细胞肌肉分化标记物(MyoD和MyoG)的蛋白表达水平。体内实验:4周后,D-gal组小鼠体质量显著下降,PBNPs干预后可显著逆转。小麦胚芽凝集素(wheat germ agglutinin,WGA)和Masson染色显示,与D-gal组比较,PBNPs干预组骨骼肌横截面积显著增加及骨骼肌组织纤维化显著改善。结论PBNPs可通过发挥抗氧化应激和改善线粒体功能的作用延缓衰老性肌萎缩的进程。展开更多
基金Project(2006CB600903) supported by the National Basic Research Program of China
文摘Prussian blue(PB) was used as catalyst to improve the extent of graphitization of polyacrylonitrile(PAN)-based carbon fibers.PB was deposited on carbon fibers by anodic electrodeposition and the thickness of PB coating(PB content) was controlled by adjusting the electrodeposition time.PAN-based carbon fibers with PB coating were heat-treated and the extent of graphitization was measured by X-ray diffractometry and Raman spectroscopy.The results indicate that the extent of graphitization of PAN-based carbon fibers is enhanced in the presence of the coating.When the PB-coated carbon fibers were heat-treated at 1 900 ℃,interlayer spacing(d002) and crystallite size(Lc) reach 0.336 8 and 21.2 nm respectively.Contrarily,the values of d002 and Lc are 0.341 4 and 7.4 nm respectively when the bare carbon fibers were heat-treated at 2 800 ℃.Compared with the bare carbon fibers,PB can make the heat treatment temperature(HTT) drop more than 500 ℃ in order to reach the same extent of graphitization.Furthermore,the research results show that PB content also has a certain influence on the extent of graphitization at the same HTT.
文摘普鲁士蓝及其类似化合物(Prussian blue analogous,PBAs)因其固有的热力学稳定性、宽广的离子插层/脱嵌通道、丰富的电化学活性位点以及可调节的化学组成与元素比例,已经成为下一代钠离子电池正极材料的有力候选者。然而,这类材料的电化学性能常常受到晶体缺陷和高含量结晶水及间隙水的影响。本文论述了PBAs的结构,并从单电子和双电子的角度概括了其分类,探讨了当前这类材料面临的挑战,并从结晶度控制、缺陷控制、形貌调控、离子掺杂/取代、组分优化以及碳包覆/复合六个方面系统地综述了现有的典型改性策略,评述了这类材料从实验室研究向产业化应用过渡的现状。此外,本文还展望了PBAs在钠离子电池领域的发展前景,通过材料工程和表面科学的进步,PBAs有望从实验室阶段迈向工业化应用。
