Enhancing cyclic voltammetry performance with N-graphene -supported coupled NiO/TiO₂ hollow nanospheres as superior anode material

In this work, we aim to study and improve the electrochemical performance of a unique thin film-structured composite nitrogen-doped graphene (NGr) combined with NiO/TiO₂ hollow nanospheres coupled by synergistic hydrothermal method. NGr@NiO/TiO₂ nanocomposites have been successfully synthesized as indicated by their characteristics through several rational characterization techniques such as the morphological shape of NiO/TiO₂ hollow nanospheres that are evenly distributed on the surface of N-graphene with particle distribution in the range of 79.78–362.13 nm with an average diameter of 130 nm. In addition, the crystal structures of carbon from NGr, NiO, and TiO₂ (anatase and rutile) have been confirmed and proven by spectra showing the presence of C–N stretching primary amides (1400 cm⁻¹), Ni–O stretching (700 cm⁻¹) and Ti–O–Ti bond (425 cm⁻¹), respectively. To enhance the performance of cyclic voltammetry (CV) in electrochemical testing, adjustments are made to parameters such as cycle effect, scan rate, and composition, ensuring the production of reversible voltammograms under each condition. The results indicate that reversible voltammograms are observed under each condition, with a composite ratio of 80:15:5 (wt%). Slower scan rates are associated with higher specific capacity (Cps), with the Cps values for the NGr@NiO/TiO₂ electrode being 741.02 F/g (80:10:10), 408.53 F/g (80:5:10), and 839.83 F/g (80:15:5), respectively. However, the highest Cps is recorded for NGr@NiO at 1959.71 F/g. Based on these findings, it is revealed that further comprehensive electrochemical testing of the NGr@NiO/TiO₂ nanocomposite is necessary, to fully explore its potential and applicability in the development of alkaline ion batteries (AIBs) such as Li/Na/K.