Recent Advancements of Niobium and Tantalum-Based Materials: From Design Engineering to Energy Storage Applications

Abstract

Niobium (Nb) and tantalum (Ta), transition metals with distinct physical and chemical properties, are highly attractive for applications in electrochemical energy storage (EES) devices. Their oxides, dichalcogenides, and MXenes demonstrate significant potential due to effective ion-diffusion channels and high theoretical capacity. Particularly, Nb-based dichalcogenides and MXenes offer enhanced electrochemical performance for lithium-ion batteries (LIBs) and supercapacitors (SCs) applications because of their layered structure. However, the tendency of Nb chalcogenides and Nb-MXene layers to aggregate or restack impedes electrolyte penetration, diminishing coulombic efficiency and capacity. Moreover, Nb- and Ta-based oxides have intrinsically low electrical conductivity and a slow Li intercalation rate, challenging their application in energy storage devices. To address these issues, strategies such as hierarchical structuring, heteroatom doping, and the development of porous or nanoscale forms, as well as composites incorporating carbon or conductive polymers, have been explored. This review summarizes the impacts of various synthesis techniques, crystal structures, and morphological tunings on the electrochemical properties of Nb and Ta materials in LIBs and SCs and outlines the future directions for enhancing their performance in EES applications.