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Highlights Easy obtention of Cu 3 (MoO 4 ) 2 (OH) 2 by sonochemistry route at room temperature. Urchin-like morphology was obtained in aqueous solution using the sonochemistry method for copper molybdate. High conversion rate in the esterification of oleic acid using the Cu 3 (MoO 4 ) 2 (OH) 2 as a solid catalyst.

In the present work, MnO 2 was electrodeposited (galvanostatic mode) on carbon cloth (CC) from manganese nitrate and sulfate precursors. Its electrochemical performance was evaluated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), which were used to study the complex behavior of the material. In CV analysis, higher cathodic and anodic loads were obtained for sulfate-MnO 2 compared with nitrate-MnO 2 , whereas in the Nyquist graphs of the EIS technique, the nitrate-MnO 2 material obtained larger charge transfer resistance (Rtc) than sulfate-MnO 2 . In the Bode analysis, the behavior of sulfate-MnO 2 was better than that of nitrate-MnO 2 . because for this analysis, the phase angle is smaller, which is attributed to better pseudocapacitive behavior of sulfate than nitrate. In capacitance and complex power terms, the relaxation time constant obtained was 2.65 s. The real capacitance in C′(ω) was 107 F g −1 for nitrate-MnO 2 and 197 F g −1 for sulfate-MnO 2 , and the intersection of the complex power curves occurred at 70%. The obtained results suggest that these materials are attractive for application in energy storage devices.

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