In the present paper, aqueous extracts ofAlchemilla Vulgaris (Aslan Pençesi) leaves have been used to prepare Fe₃O₄ nano-flakes accompanied by calcination at 400°C. The various properties of biosynthesised Fe₃O₄ nano-flakes were investigated using UV–Visible, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), X-Ray diffraction (XRD), cyclic voltammetry, thermogravimetric (TG), and differential thermal analysis (DTA) respectively. The SEM study reveals the formation of flake-like structure with a diameter of 85 nm and a thickness of 9 nm respectively. The DTA curve shows two endothermic peaks corresponding to the decomposition of organic matter and the deoxidation of FeO (Wustite) to α-Fe, respectively, and their activation energy values were found to be 5.73 and 16.43 kJ/moles, respectively. The green synthesised magnetite nano-flakes is proved to be an excellent electrocatalyst for the electro-oxidation of ascorbic acid. The effect of scan rates, the concentration of the modifier, and the analyte was also investigated.

We have successfully studied the charge transfer kinetics between carbon paste electrodes and dopamine using green synthesized rectangular monoclinic CuO nanoparticles (NPs) prepared by Alchemilla vulgaris leaves with the one-pot green synthesis method. The scanning electron microscopy (SEM) results confirmed the monoclinic structure with a particle size of around 85 nm. The investigation of thermal properties was carried out by thermogravimetric (TG) and differential thermal analysis (DTA). We also studied the electrochemical response of green synthesized CuO nanoparticles to detect Dopamine (DA) using cyclic voltammetry, which was proven to be an excellent electrocatalyst for the electro-oxidation of DA. The fabricated CuO nanoparticle modified carbon paste electrode (CMCPE) depicts fantastic selectivity, robustness, and sensitivity in analyzing DA in clinical and pharmaceutical preparations. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) orbitals of the DA were studied using positive and negative charges at the CuO modified carbon paste electrode interface. Frontier molecular orbitals of DA are plotted to understand electron transfer reactivity at the electrode interface.