硅负极材料因具有较高的理论容量(Li22Si5合金相对应4200 mAh/g)、较低的工作电压(0.2~0.3 V vs Li/Li+)和地球上丰富的原材料储备,成为代替石墨负极的理想材料之一。但是,低电导率及在循环过程中发生剧烈体积膨胀导致电极失效问题限制...硅负极材料因具有较高的理论容量(Li22Si5合金相对应4200 mAh/g)、较低的工作电压(0.2~0.3 V vs Li/Li+)和地球上丰富的原材料储备,成为代替石墨负极的理想材料之一。但是,低电导率及在循环过程中发生剧烈体积膨胀导致电极失效问题限制了硅负极材料的进一步发展。因此,本工作通过物理法利用壳聚糖和石墨对纳米硅实现碳包覆和复合,制备壳聚糖/石墨@纳米硅复合材料(C/G@Si复合材料),对C/G@Si复合材料的结构、形貌和电化学性能进行研究。结果表明:随着石墨添加量的提高,C/G@Si复合材料的可逆比容量略微下降,循环性能和导电性能显著提高。当添加50%(质量分数)石墨时,在100 mA/g的电流密度下,C/G@Si复合材料的首次放电比容量为1136.1 mAh/g,循环充放电100次后剩余容量保持在658.5 mAh/g,展示出优异的电化学性能,对进一步推广硅碳负极材料具有一定的参考价值。展开更多
According to people in the museum industry, subject to a variety of conditions, no country in the world has completed the digital recording ot all their cultural relics including buildings. When it comes to the diffic...According to people in the museum industry, subject to a variety of conditions, no country in the world has completed the digital recording ot all their cultural relics including buildings. When it comes to the difficulties, they hold that raising awarencss is the top priority. Recognizing the importance of digitization is the most important and difficult task.展开更多
文摘硅负极材料因具有较高的理论容量(Li22Si5合金相对应4200 mAh/g)、较低的工作电压(0.2~0.3 V vs Li/Li+)和地球上丰富的原材料储备,成为代替石墨负极的理想材料之一。但是,低电导率及在循环过程中发生剧烈体积膨胀导致电极失效问题限制了硅负极材料的进一步发展。因此,本工作通过物理法利用壳聚糖和石墨对纳米硅实现碳包覆和复合,制备壳聚糖/石墨@纳米硅复合材料(C/G@Si复合材料),对C/G@Si复合材料的结构、形貌和电化学性能进行研究。结果表明:随着石墨添加量的提高,C/G@Si复合材料的可逆比容量略微下降,循环性能和导电性能显著提高。当添加50%(质量分数)石墨时,在100 mA/g的电流密度下,C/G@Si复合材料的首次放电比容量为1136.1 mAh/g,循环充放电100次后剩余容量保持在658.5 mAh/g,展示出优异的电化学性能,对进一步推广硅碳负极材料具有一定的参考价值。
文摘According to people in the museum industry, subject to a variety of conditions, no country in the world has completed the digital recording ot all their cultural relics including buildings. When it comes to the difficulties, they hold that raising awarencss is the top priority. Recognizing the importance of digitization is the most important and difficult task.