Effects of various molarities of nickel oxide on the aggregate 1D–3D structure and its electrochemical activity

Porous 3D columnar-sphere of NiO nanomaterials synthesized for supercapacitors via hydrothermal route: impact of thiourea concentration

“…15 Small peaks of C-O bonds were observed around 1392 cm À1 in all of the samples. 6 The vibrations of the Ni-O bonds are represented by the strong absorption band at 433 cm À1 and 690 cm À1 in all of the samples. 6,16 In addition, a small content of sulphur (S) was detected at 1283 cm À1 , as shown in the inset of Fig.…”

“…The Ni and O peaks are visible in sample TN 4 , along with other peaks resulting from the channeling effect of the X-ray on the stainless steel 304 substrate surface. 6 EDAX also indicates the occurrence of surface-sulphuration of NiO materials. 17 Here, the contact angles for the TN 1 , TN 2 , TN 3 , TN 4 , and TN 5 samples with the electrolyte interface are determined to be 661, 341, 311, 251, and 831, respectively.…”

“…The TN 4 electrode's CV curves revealed the redox pseudocapacitive behaviors of the NiO material. 6,19 In the redox reactions, the NiO nanomaterials interact with the potassium hydroxide species to form nickel hydroxide. Furthermore, this nickel hydroxide is converted into nickel oxyhydroxides and vice versa.…”

“…The various dimensional structures, such as 0D, 1D, 2D, and 3D porous structures, result in differences in surface area, pore size, particle size, and shape, which further affect the performance of supercapacitors. 6 The fabrication of extremely porous materials improves electrochemical capacitor performance. Various porous morphological materials are fabricated using different structuredirecting agents such as urea, thiourea, glycol, and sodium dodecyl sulphate (SDS).…”

“…Various porous morphological materials are fabricated using different structuredirecting agents such as urea, thiourea, glycol, and sodium dodecyl sulphate (SDS). [6][7][8] Suqing Ci et al reported that urea and SDS are used for the formation of micro-flowers constructed from NiO nanosheets, which show a maximum specific capacitance of 1579 F g À1 at 1 mV s À1 scan rate. 9 Yaping Zeng et al demonstrated that ethylene glycol helps to modify the surface energy in NiO and form self-assembled 3D spheres, which exhibit a specific capacitance of 532 F g À1 at a current density of 2 A g À1 .…”