Rational Design of 2D/3D BiOSe-CNT Hybrid Architectures for Synergistic Lithium Storage.

The development of advanced anode materials with high capacity and structural stability addressing the limitations of conventional graphite anodes in theoretical capacity (372 mA h g) and severe volume expansion remains a critical challenge for lithium-ion batteries (LIBs). Herein, we propose a structural engineering strategy through high-temperature calcination to construct 2D layered BiOSe integrated with optimized 3D carbon nanotube (CNT) frameworks (BiOSe-CNT-x). Comprehensive characterization (XRD, Raman, FESEM, XPS) verifies the high crystallinity of BiOSe and the successful establishment of 3D conductive networks through interfacial coupling with CNTs. Electrochemical evaluation demonstrates that the optimized BiOSe-CNT-2 composite delivers a remarkable initial discharge capacity of 1544.7 mA h g at 0.1 A g, significantly outperforming pristine BiOSe (124.3 mA h g). Notably, it maintains superior rate capability (405.0 mA h g at 2 A g, 35.2% capacity retention) and cycling stability (74.8% capacity retention after 250 cycles), attributed to the synergistic effects between 2D BiOSe lamellae and the conductive CNT matrix. The 3D CNT network facilitates rapid electron transport while mitigating volume fluctuations, whereas the layered BiOSe enables a hybrid storage mechanism combining intercalation, conversion, and alloying reactions. This work broadens the application horizons of 2D layered materials in energy storage systems.