Direct carbon solid oxide fuel cells(DC-SOFCs)are promising,green,and efficient power-generating devices that are fueled by solid carbons and comprise all-solid-state structures.Developing suitable anode materials for...Direct carbon solid oxide fuel cells(DC-SOFCs)are promising,green,and efficient power-generating devices that are fueled by solid carbons and comprise all-solid-state structures.Developing suitable anode materials for DC-SOFCs is a substantial scientific challenge.Herein we investigated the use of La_(0.75)Sr_(0.25)Cr_(0.5)Mn_(0.5)O_(3)-δ−Ce_(0.8)Gd_(0.2)O_(1.9)(LSCM−GDC)composite electrodes as anodes for La_(0.9)Sr_(0.1)Ga_(0.8)Mg_(0.2)O_(3)-δelectrolyte-based DC-SOFCs,with Camellia oleifera shell char as the carbon fuel.The LSCM−GDC-anode DC-SOFC delivered a maximum power density of 221 mW/cm^(2) at 800℃ and it significantly improved to 425 mW/cm^(2) after Ni nanoparticles were introduced into the LSCM−GDC anode through wet impregnation.The microstructures of the prepared anodes were characterized,and the stability of the anode in a DC-SOFC and the influence of catalytic activity on open circuit voltage were studied.The above results indicate that LSCM–GDC anode is promising to be applied in DC-SOFCs.展开更多
本文以管状和盘状两种天然硅藻土作为初始原料,制备了一系列硅藻土衍生硅碳负极材料,并采用X射线衍射仪(XRD)、拉曼光谱(Raman)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X-射线光电子能谱(XPS)等测试手段系统表征了所制备样品的晶...本文以管状和盘状两种天然硅藻土作为初始原料,制备了一系列硅藻土衍生硅碳负极材料,并采用X射线衍射仪(XRD)、拉曼光谱(Raman)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X-射线光电子能谱(XPS)等测试手段系统表征了所制备样品的晶体结构、微观形貌及化学组成.将制备的硅藻土衍生硅碳负极材料作为活性物质组装为锂离子电池,对比了管状和盘状两种形貌对其储锂性能的影响,并详细考察了沥青衍生碳包覆层的加入量对硅碳负极材料比容量及循环稳定性的影响.测试结果表明,样品管DE-1∶3和管DE-1∶6在0.2 A g^(-1)较低电流密度下均具有较好的容量保持率,循环500次之后比容量分别可保持443 mAh g^(-1)和414 mAh g^(-1),而样品管DE-1∶6则在0.5 A g^(-1)较大电流密度下具有更好的结构稳定性.展开更多
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
基金Project(2019YFC1907405)supported by the National Key R&D Program of ChinaProject(GJJ200809)supported by the Education Department Project Fund of Jiangxi Province,ChinaProject(2020BAB214021)supported by the Natural Science Foundation of Jiangxi Province,China。
文摘Direct carbon solid oxide fuel cells(DC-SOFCs)are promising,green,and efficient power-generating devices that are fueled by solid carbons and comprise all-solid-state structures.Developing suitable anode materials for DC-SOFCs is a substantial scientific challenge.Herein we investigated the use of La_(0.75)Sr_(0.25)Cr_(0.5)Mn_(0.5)O_(3)-δ−Ce_(0.8)Gd_(0.2)O_(1.9)(LSCM−GDC)composite electrodes as anodes for La_(0.9)Sr_(0.1)Ga_(0.8)Mg_(0.2)O_(3)-δelectrolyte-based DC-SOFCs,with Camellia oleifera shell char as the carbon fuel.The LSCM−GDC-anode DC-SOFC delivered a maximum power density of 221 mW/cm^(2) at 800℃ and it significantly improved to 425 mW/cm^(2) after Ni nanoparticles were introduced into the LSCM−GDC anode through wet impregnation.The microstructures of the prepared anodes were characterized,and the stability of the anode in a DC-SOFC and the influence of catalytic activity on open circuit voltage were studied.The above results indicate that LSCM–GDC anode is promising to be applied in DC-SOFCs.
文摘本文以管状和盘状两种天然硅藻土作为初始原料,制备了一系列硅藻土衍生硅碳负极材料,并采用X射线衍射仪(XRD)、拉曼光谱(Raman)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X-射线光电子能谱(XPS)等测试手段系统表征了所制备样品的晶体结构、微观形貌及化学组成.将制备的硅藻土衍生硅碳负极材料作为活性物质组装为锂离子电池,对比了管状和盘状两种形貌对其储锂性能的影响,并详细考察了沥青衍生碳包覆层的加入量对硅碳负极材料比容量及循环稳定性的影响.测试结果表明,样品管DE-1∶3和管DE-1∶6在0.2 A g^(-1)较低电流密度下均具有较好的容量保持率,循环500次之后比容量分别可保持443 mAh g^(-1)和414 mAh g^(-1),而样品管DE-1∶6则在0.5 A g^(-1)较大电流密度下具有更好的结构稳定性.
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。
