Structural, optical, and electrical investigation of multilayered MnO2(n)/ NiO(p) heterojunctions for supercapacitors applications
Küçük Resim Yok
Tarih
2023
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Elsevier
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Heterojunctions of alternating MnO2 and NiO thin films were deposited on an Indium Tin Oxide (ITO). The MnO2 and NiO thin films were synthesized by electrodeposition and sol-gel methods respectively. The structural morphology of the synthesized heterojunctions was investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The microstructural and chemical compositions were examined by X-ray diffraction (XRD), Fourier transform infrared (FTIR), and Raman techniques. The optical properties were investigated by Ultraviolet-Visible (UV) analysis. The electrical conductivity, specific capacitance, and charge carrier density were determined using the Hall effect and Electrochemical impedance spectroscopy (EIS) methods. As a result, it was found that the MnO2 and NiO thin films crystallize in tetragonal and cubic crystal systems respectively. Increasing the number of NiO/MnO2 heterojunctions increases the electrical conductivity from 9.7 x 10- 7 to 1.2 x 10-3 S.cm- 1, the bandgap decreased 3.16 to 2.62 eV, the volume carrier density rises from 5.17 x 1011 to 4.62 x 1012 cm-3. The specimens constituted of two and four alternative staked MnO2 and NiO layers are characterized by a specific capacitance of 3.6 x 103 and 5.8 x 103 F.g -1 and capacitance retention of 14.8 and 12.9% which consider them promising materials for supercapacitor devices.
Açıklama
Anahtar Kelimeler
Heterojunction, MnO2, NiO, Supercapacitor, Specific capacitance, Thin-Films, Nanoparticles
Kaynak
Surfaces And Interfaces
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
42
