O-Vacancy-enriched NiO hexagonal platelets fabricated on Ni foam as a self-supported electrode for extraordinary pseudocapacitance
O-Vacancy-enriched NiO hexagonal platelets fabricated on Ni foam as a self-supported electrode for extraordinary pseudocapacitance
复制标题
在泡沫镍上制备的富含 O 空位的 NiO 六方片作为自支撑电极，具有非凡的赝电容
DOI：
10.1039/c8ta00044a
复制
发表时间：
2018-04-28
影响因子：
11.9
通讯作者：
Pan, Fusheng
中科院分区：
文献类型：
--
作者：
Li, Lingjie;Zhang, Jie;Pan, Fusheng
为了提高NiO基电极的电容性能，采用水热法在泡沫镍集流体上原位制备了富含氧空位的NiO六方片晶.由于NiO的自生长性质和丰富的氧空位，所制备的自支撑NiO电极表现出非凡的赝电容。当扫描速率为1 mV·s（-1）时，所制备的NiO电活性材料的比电容为2495 F·g（-1），接近NiO理论值的97%，当电流密度从0.5增加到10A·g（-1）时，电容保持率大于80%. DFT计算研究证明了氧空位在增加电导率、电化学活性位点和表面反应性方面的重要作用，这在很大程度上解释了显着高的比电容和倍率性能。该研究将进一步拓宽NiO基材料的应用领域，并推动对氧非化学计量比的研究。
To enhance the capacitive property of NiO-based electrodes, O-vacancy-enriched NiO hexagonal platelets have been fabricated in situ on an Ni foam current collector by a facile hydrothermal treatment of Ni foam in a H2O2 aqueous solution and subsequent calcination in N-2 atmosphere. Due to the self-grown nature and the abundant oxygen vacancies, the as-prepared self-supported NiO electrode showed extraordinary pseudocapacitance. The specific capacitance of the as-prepared NiO electroactive materials was 2495 F g(-1) at a scan rate of 1 mV s(-1) (similar to 97% of the theoretical value of NiO) and the capacitance retention was higher than 80% when the current density increased from 0.5 to 10 A g(-1). DFT computational studies proved the vital role of oxygen vacancies in increasing the conductivity, electrochemical active sites and surface reactivity, which substantially account for the significantly high specific capacitance and rate capability. This study may further broaden the applications of NiO-based materials and boost the research on oxygen nonstoichiometry.