https://doi.org/10.1016/j.est.2025.115289
Abstract
This review provides a comprehensive overview of recent advancements in TiO₂-based nanomaterials as electrodesfor supercapacitors, emphasizing strategies that enhance their electrochemical performance. It details thesynthesis methods and modification techniques such as hybridization with carbon-based materials, metal iondoping, and combination with pseudocapacitive materials of various TiO₂nanoarchitectures, including 0-Dnanoparticles, 1-D nanowires, nanorods, nanofibers, nanotubes, 2-D nanosheets, and 3-D nanocomposites forsupercapacitor electrodes. The impact of these modifications on key performance parameters, such as specificcapacitance, energy and power densities, and cycle life, is critically evaluated. Notably, we highlight the significantimprovements in energy density achieved through the aforementioned modifications, reaching values of~102 Wh kg-1at power densities nearing 104 W kg-1. The review also addresses ambiguities in the interpretationof charge storage mechanisms, providing clarity on electric double-layer capacitance, pseudocapacitance,and battery-type intercalation, and critically examines inconsistencies in their classification and analysis in theliterature. It categorizes supercapacitors based on their electrode types, distinguishing between symmetric,asymmetric, and hybrid configurations, and underscores the performance impact of different charge storageprocesses. The review concludes by outlining future research directions to further optimize TiO₂-based electrodeperformance to facilitate their widespread application in high-performance energy storage devices.
