Balancing Power and Stability: A Comparative Study of Oxide and Sulfide Anodes for Next-Generation Energy Storage

The accelerating demand for high-performance energy storage systems, driven by renewable energy integration and the electrification of transportation, necessitates the development of next-generation batteries with higher energy density, enhanced safety, and long-term stability. Among various anode materials, transition-metal oxides (TMOs) and transition-metal sulfides (TMSs) have emerged as two highly promising families due to their structural versatility, abundant redox-active centers, and cost-effective synthesis. TMOs, such as MnO₂ and Fe₂O₃, offer high theoretical capacities and chemical robustness but are hindered by poor electronic conductivities and sluggish ion transport. In contrast, TMSs, such as FeS₂ and VS₂, exhibit superior electrical conductivity, multielectron redox activity, and high energy density; however, they suffer from severe polysulfide dissolution, large volume expansion, and interfacial instability. This review provides a comprehensive comparison of TMOs and TMSs in terms of their electrochemical performance, synthesis strategies, and structural evolution during cycling. Furthermore, it highlights recent advances in structural engineering techniques, such as high-entropy strategies, defect modulation, and crystal facet engineering, that address their intrinsic limitations. Finally, emerging research directions and green synthesis strategies are discussed, offering a critical perspective on the future design of oxide- and sulfide-based anodes for high-performance lithium- and sodium-ion batteries.