This article reports that extremely thin nanobelts(thickness~10 nm)exhibit pseudocapacitive(PC)charge storage in the asymmetric supercapacitor(ASC)configuration,while show battery-type charge storage in their single e...This article reports that extremely thin nanobelts(thickness~10 nm)exhibit pseudocapacitive(PC)charge storage in the asymmetric supercapacitor(ASC)configuration,while show battery-type charge storage in their single electrodes.Two types of nanobelts,viz.NiO-Co_(3)O_(4) hybrid and spinal-type NiCo_(2)O_(4),developed by electrospinning technique are used in this work.The charge storage behaviour of the nanobelts is benchmarked against their binary metal oxide nanowires,i.e.,NiO and Co_(3)O_(4),as well as a hybrid of similar chemistry,CuO-Co_(3)O_(4).The nanobelts have thickness of~10 nm and width~200 nm,whereas the nanowires have diameter of~100 nm.Clear differences in charge storage behaviours are observed in NiO-Co_(3)O_(4) hybrid nanobelts based ASCs compared to those fabricated using the other materials-the former showed capacitive behav-iour whereas the others revealed battery-type discharge behaviour.Origin of pseudocapacitance in nanobelts based ASCs is shown to arise from their nanobelts morphology with thickness less than typical electron diffusion lengths(~20 nm).Among all the five type of devices fabricated,the NiO-Co_(3)O_(4) hybrid ASCs exhibited the highest specific energy,specific power and cycling stability.展开更多
基金This work is supported by the Research and Inno-vation Department of University Malaysia Pahang(http://ump.edu.my)under the Flagship Leap 3 Program(RDU172201).
文摘This article reports that extremely thin nanobelts(thickness~10 nm)exhibit pseudocapacitive(PC)charge storage in the asymmetric supercapacitor(ASC)configuration,while show battery-type charge storage in their single electrodes.Two types of nanobelts,viz.NiO-Co_(3)O_(4) hybrid and spinal-type NiCo_(2)O_(4),developed by electrospinning technique are used in this work.The charge storage behaviour of the nanobelts is benchmarked against their binary metal oxide nanowires,i.e.,NiO and Co_(3)O_(4),as well as a hybrid of similar chemistry,CuO-Co_(3)O_(4).The nanobelts have thickness of~10 nm and width~200 nm,whereas the nanowires have diameter of~100 nm.Clear differences in charge storage behaviours are observed in NiO-Co_(3)O_(4) hybrid nanobelts based ASCs compared to those fabricated using the other materials-the former showed capacitive behav-iour whereas the others revealed battery-type discharge behaviour.Origin of pseudocapacitance in nanobelts based ASCs is shown to arise from their nanobelts morphology with thickness less than typical electron diffusion lengths(~20 nm).Among all the five type of devices fabricated,the NiO-Co_(3)O_(4) hybrid ASCs exhibited the highest specific energy,specific power and cycling stability.