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A fast and facile electrochemical method called electrooxidation was used to prepare SnO2 nanoparticles. In this route, a sacrificial tin anode is dissolved in an electrolyte by applying a voltage to an electrochemical cell. We used different electrolyte environments, namely tetramethylammonium chloride and different counterions of tetrabutylammonium cation, viz. Br−, Cl−, and ClO4−. Characterization results showed that the size distribution was more uniform for the nanoparticles created with Br− and Cl− counterions. Furthermore, the particles in these samples were smaller than in the others. The amount of OH groups on the surface of the Br− and Cl− samples was higher than for the other samples, enhancing dye adsorption. Dye-sensitized solar cells (DSSCs) were fabricated from the produced SnO2 nanoparticles, and the influence of the different counterions on their performance was investigated. By varying the counterion in the electrolyte, samples with different hydrophilic nature and dye-loading ability were obtained. The dye adsorption and consequently the current density of the cell made from the Br− solution were higher than for the other samples, and the power conversion efficiency in this case reached 1.5%. [ABSTRACT FROM AUTHOR]

Owing to the high demands for fascinating energy storage devices, exploring cost-effective electrodes with exclusive architectures for supercapacitors is crucial; however, the advent of such electrodes to achieve the industrial necessities remains a challenging task. Herein the design and characterization of roselike nanoporous ZnGa2S4 hollow spheres (RN-ZGSHS) are described. This structure with the surface area of 71.7 m2 g−1 can provide a capacity of 358.4 mAh g−1 at 2 A g−1 and capacity of 260.2 mAh g−1 at 50 A g−1, as well as significant robustness of 98.4%. To achieve higher energy density in the asymmetric energy storage device, a yolk-shell nanoporous iron phosphide hollow spheres (YS–FePHS) as a negative electrode is also designed. The designed anode electrode with a quasi-rectangular-like character can deliver a capacity of 117.5 mAh g−1 at 1 A g−1 and maintains a high capacity of 65.8 mAh g−1 at 25 A g−1, with satisfactory robustness of 89.9%. Ultimately, the constructed asymmetric device (RN-ZGSHS//YS-FePHS) depicts the ED of 72.78 W h kg−1 at a power density (PD) of 800 W kg−1, while keeps a high energy density of 49.13 W h kg−1 at a power density of 64148.53 W kg−1. Image 1 • Rose-like nanoporous ZnGa 2 S 4 hollow spheres are synthesized as cathode electrode. • Yolk-shell nanoporous iron phosphide hollow spheres are prepared as anode electrode. • Cathode and anode electrodes exhibit high electrochemical performance. • An asymmetric supercapacitor is assembled based on cathode and anode electrodes. • The asymmetric supercapacitor illustrates excellent energy density. [ABSTRACT FROM AUTHOR]