Preparation and capacitance of MnO2 pillared Co2+-Ni2+-Fe3+ layered double hydroxide porous material supercapacitor

MnO2 pillared Co2+-Ni2+-Fe3+ layered double hydroxide nanocomposite with porous structure has been successfully prepared by using an intercalation/reduction reaction and followed by heating treatment. The structural evolution of the samples obtained at different stages are characterized by X-ray diffraction, field emission scanning electron microscopy, infrared spectroscopy, X-ray photoelectron spectroscopy, and N-2 adsorption-desorption analyses. MnO2 as a pillared agent can stabilize the layered structure against thermal treatment, and porous Co2+-Ni2+-Fe3+ layered double hydroxide nanocomposite is obtained by heating the MnO2 pillared material at appropriate temperatures. The basal spacing of the obtained intermediates changes with the radius of the pillar species in the interlayer and the layered structure with larger surface area can maintain to 300 degrees C. The as prepared MnO2-LDHs (200) material not only has large specific surface area of 145 m(2) g(-1), but also shows an ideal capacitance of 389 F g(-1) at a scan rate of 5 mV s(-1) and good capacitance retention of 92.3% after 500 cycles at a scan rate of 20 mV s(-1) in 1 mol L-1 KOH solution, making this material has a potential application as supercapacitor electrode material. (C) 2017 Elsevier B.V. All rights reserved.