Materials Science and Engineering Program and Texas Materials Institute , The University of Texas at Austin , Austin , Texas 78712 , United States.
Department of Chemistry , Mississippi State University , Mississippi State , Mississippi 39762 , United States.
ACS Appl Mater Interfaces. 2018 Jun 27;10(25):21262-21280. doi: 10.1021/acsami.8b03606. Epub 2018 Jun 13.
We develop zirconium-templated NiO/NiOOH nanosheets on nickel foam and polypyrrole-embedded in exfoliated carbon fiber cloth as complementary electrodes for an asymmetric battery-type supercapacitor device. We achieve high volumetric energy and power density by the modification of commercially available current collectors (CCs). The modified CCs provide the source of active material, actively participate in the charge storage process, provide a larger surface area for active material loading, need no additional binders or conductive additives, and retain the ability to act as the CC. Nickel foam (NF) CCs are modified by use of a soft-templating/solvothermal treatment to generate NiO/NiOOH nanosheets, where the NF is the source of Ni for the synthesis. Carbon-fiber cloth (CFC) CCs are modified by an electrochemical oxidation/reduction process to generate exfoliated core-shell structures (ECFC). Electropolymerization of pyrrole into the shell structure produces polypyrrole embedded in exfoliated core-shell material (PPy@rECFC). Battery-type supercapacitor devices are produced with NiO/NiOOH@NF and PPy@rECFC as positive and negative electrodes, respectively, to demonstrate the utility of this approach. Volumetric energy densities for the full-cell device are in the range of 2.60-4.12 mWh cm with corresponding power densities in the range of 9.17-425.58 mW cm. This is comparable to thin-film lithium-ion batteries (0.3-10 mWh cm) and better than some commercial supercapacitors (<1 mWh cm). The energy and power density is impressive considering that it was calculated using the entire cell volume (active materials, separator, and both CCs). The full-cell device is highly stable, retaining 96% and 88% of capacity after 2000 and 5000 cycles, respectively. These results demonstrate the utility of directly modifying the CCs and suggest a new method to produce high volumetric energy density and power density storage devices.
我们在泡沫镍和嵌入剥离碳纤维布中的聚吡咯上开发了氧化锆模板化的 NiO/NiOOH 纳米片，作为非对称电池型超级电容器器件的互补电极。我们通过修饰市售的集流器 (CC) 实现了高体积能量和功率密度。修饰后的 CC 提供了活性材料的来源，积极参与电荷存储过程，为活性材料提供了更大的负载表面积，不需要额外的粘结剂或导电添加剂，并保留了作为 CC 的能力。使用软模板/溶剂热处理来修饰泡沫镍 (NF) CC 以生成 NiO/NiOOH 纳米片，其中 NF 是合成的 Ni 的来源。通过电化学氧化/还原过程修饰碳纤维布 (CFC) CC 以生成剥离的核壳结构 (ECFC)。将吡咯电聚合到壳结构中生成嵌入剥离核壳材料中的聚吡咯 (PPy@rECFC)。用 NiO/NiOOH@NF 和 PPy@rECFC 分别作为正负极制备电池型超级电容器器件，以证明该方法的实用性。全电池器件的体积能量密度范围为 2.60-4.12 mWh cm，相应的功率密度范围为 9.17-425.58 mW cm。这与薄膜锂离子电池（0.3-10 mWh cm）相当，优于一些商业超级电容器（<1 mWh cm）。考虑到它是使用整个电池体积（活性材料、分离器和两个 CC）计算得出的，这个能量和功率密度令人印象深刻。全电池器件高度稳定，在 2000 和 5000 次循环后分别保持 96%和 88%的容量。这些结果证明了直接修饰 CC 的实用性，并提出了一种生产高体积能量密度和功率密度存储器件的新方法。
