ZnO nanorods inserted graphene sheets with improved supercapacitive performance

The effect of SiO2 nanoparticles dispersion on physico-chemical properties of modified Ni–W nanocomposite coatings

“…Further, there is an important presence of SiO 2 agglomerates onto the copper surface at the beginning of the electrodeposition process. This behavior is related to the electronic affinity of Cu to oxides complexes especially silicon based compounds as mentioned elsewhere [25][26][27]. In conclusion, it could be seen from Fig.…”

“…3C, EDS spectrum recorded a higher silicon presence (unreported result). Therefore, this structure has been referred to the adsorption of amorphous silica agglomerate according to a similar morphology observed and verified elsewhere [25][26][27]. On the other hand, the SEM micrograph of Ni-W/SiO 2 nanocomposite coated at pH 4 (Fig.…”

“…In fact, zêta potential determined the static electricity force among nano-SiO 2 particles and influenced greatly the character either agglomeration or dispersion among the nanoparticles [23][24][25]. When the nanoparticles of SiO 2 became close to the cathode, the repulsion force among the double-charge layers of nanoparticles and increased the possibility of conglobation among nanoparticles.…”

One-pot electrodeposition synthesis of ZnO/graphene composite and its use as binder-free electrode for supercapacitor

“…[26] However, the whole of preparation process discussed above involve two different steps, including the reduction of graphene oxide (GO) and the following insertion of ZnO nanostructure by various synthesis techniques. Furthermore, in many previous reports, [25,[30][31][32] the supercapacitors electrodes are usually fabricated by coating the mixture of polymer conductive additive with active materials to the collectors, the introduction of polymer binder increases the adhesion strength of the electrode but at the expense of the electrode's conductivity and electrochemical performance.…”

“…[24] What's more, having a high energy density of 650 Ag-1, ZnO is also a promising active material for supercapacitors, due to its significant advantages of low cost, abundant availability, environmental friendly nature and electrochemical activity. [25,26] Up to now, various research interests have been focus on structurally integrating presented the preparation of ZnO/reduced graphite oxide composite using a two-step method in which KOH reacts with Zn(NO 3 ) 2 in the aqueous dispersions of graphite oxide to form a Zn(OH) 2 /graphite oxide precursor, followed by thermal treatment, which provided a specific capacitance as high as 308 Fg -1 at the current density of 1 Ag -1 . [26] However, the whole of preparation process discussed above involve two different steps, including the reduction of graphene oxide (GO) and the following insertion of ZnO nanostructure by various synthesis techniques.…”