将醋酸镍和葡萄糖溶于水中,与氧化石墨烯(GO)水悬浮液均匀混合,在180℃下水热处理24 h,再在Ar中700℃下炭化3 h,然后在空气中300℃下煅烧3 h得到三维Ni/NiO@C/GN。结果表明,水热处理过程中葡萄糖衍生的炭层将Ni(OH)2完全包裹,并在炭化...将醋酸镍和葡萄糖溶于水中,与氧化石墨烯(GO)水悬浮液均匀混合,在180℃下水热处理24 h,再在Ar中700℃下炭化3 h,然后在空气中300℃下煅烧3 h得到三维Ni/NiO@C/GN。结果表明,水热处理过程中葡萄糖衍生的炭层将Ni(OH)2完全包裹,并在炭化过程中转化为金属Ni,部分金属Ni在空气中煅烧中被氧化为NiO。当作为锂离子电池的负极材料时,其初始容量为711.6 mA h g^(-1),300次循环后增加到772.1 mA h g^(-1)。作为对比,没有添加GO的材料的初始容量较低,仅为584.7 mA h g^(-1),300次循环后下降到148.8 mA h g^(-1)。这些结果表明炭层可以抑制Ni/NiO纳米颗粒的团聚,有效缓解锂化过程中的体积膨胀,抑制循环过程中的电极开裂。GO的加入可形成丰富的导电网络,提高导电性。较大的比表面积可增加活性位点,有利于电解液快速浸润电极材料。这些因素显著改善了Ni/NiO@C/GN负极的电化学性能。展开更多
A new route to synthesize TS-1 has been developed using the supercritical carbon dioxide（SCCO2） as a crystallization-assistant agent. SCCO2 plays a dual role： as a reagent changing the alkalinity during the crystal...A new route to synthesize TS-1 has been developed using the supercritical carbon dioxide（SCCO2） as a crystallization-assistant agent. SCCO2 plays a dual role： as a reagent changing the alkalinity during the crystallization process and as a medium eliminating mass-transfer limitations（both within the bulk fluid and through liquid/gas, solid/gas or solid/liquid phase boundaries）. In this route, it was shown that the Ti content in TS-I increase compared with that in the TS-1 prepared without SCCO2, but decrease while the SCCO2 pressure increase. The prepared crystal morphology also underwent significant change. The crystallization time of TS-1 can be shorten a lot.展开更多
文摘将醋酸镍和葡萄糖溶于水中,与氧化石墨烯(GO)水悬浮液均匀混合,在180℃下水热处理24 h,再在Ar中700℃下炭化3 h,然后在空气中300℃下煅烧3 h得到三维Ni/NiO@C/GN。结果表明,水热处理过程中葡萄糖衍生的炭层将Ni(OH)2完全包裹,并在炭化过程中转化为金属Ni,部分金属Ni在空气中煅烧中被氧化为NiO。当作为锂离子电池的负极材料时,其初始容量为711.6 mA h g^(-1),300次循环后增加到772.1 mA h g^(-1)。作为对比,没有添加GO的材料的初始容量较低,仅为584.7 mA h g^(-1),300次循环后下降到148.8 mA h g^(-1)。这些结果表明炭层可以抑制Ni/NiO纳米颗粒的团聚,有效缓解锂化过程中的体积膨胀,抑制循环过程中的电极开裂。GO的加入可形成丰富的导电网络,提高导电性。较大的比表面积可增加活性位点,有利于电解液快速浸润电极材料。这些因素显著改善了Ni/NiO@C/GN负极的电化学性能。
基金National Basic Research Program of China,the National Natural Science Foundation of China,the Youth Scientific Research Fund of Jilin Province,China
文摘A new route to synthesize TS-1 has been developed using the supercritical carbon dioxide（SCCO2） as a crystallization-assistant agent. SCCO2 plays a dual role： as a reagent changing the alkalinity during the crystallization process and as a medium eliminating mass-transfer limitations（both within the bulk fluid and through liquid/gas, solid/gas or solid/liquid phase boundaries）. In this route, it was shown that the Ti content in TS-I increase compared with that in the TS-1 prepared without SCCO2, but decrease while the SCCO2 pressure increase. The prepared crystal morphology also underwent significant change. The crystallization time of TS-1 can be shorten a lot.
