The orthorhombic and hydrated vanadium pentoxide (V₂O₅) films are fabricated via a facile electrodeposition method followed with a controllable annealing process. Served as sodium ion batteries (SIBs) cathode, the hydrated V₂O₅ film exhibits enhanced sodium storage performance over the orthorhombic V₂O₅ film, originating from faster diffusion reaction kinetics, better electrochemical reaction reversibility, and smaller electrochemical reaction resistance. To be specific, the hydrated V₂O₅ film maintains a high capacity of 166 mAh g⁻¹ after 100 charge-discharge cycles at 200 mA g⁻¹ between −1.5 V and 0.5 V (vs. an Ag/Ag⁺ reference electrode). Moreover, it reveals outstanding rate capability with reversible discharge capacities of 133 mAh g⁻¹ at 1000 mA g⁻¹ and 121 mAh g⁻¹ at 2000 mA g⁻¹, which are higher than those of orthorhombic V₂O₅ film (41 mAh g⁻¹ at 1000 mA g⁻¹ and 34 mAh g⁻¹ at 2000 mA g⁻¹). The significant enhancement in sodium-ion storage capacity and high-rate performance of the hydrated V₂O₅ film is mainly due to its lager interlamellar spacing, which can promote the insertion/extraction of Na⁺, and the presence of V⁴⁺ accompanied with oxygen vacancies, which might improve the electronic conductivity and alleviate the stress caused by volume expansion.

斜方晶和水合五氧化二钒（V ₂ O ₅）膜是通过一种简便的电沉积方法，然后进行可控的退火工艺制成的。担任钠离子电池（SIB）的阴极，水合V ₂ ø ₅膜表现出增强的存储钠性能在斜方晶V ₂ ø ₅膜，从更快的扩散反应动力学，更好的电化学反应可逆性始发，和较小的电化学反应的阻力。具体而言，水合的V ₂ O ₅膜在200 mA g ^-1下经过100次充放电循环后仍保持166 mAh g ^-1的高容量。介于-1.5 V和0.5 V之间（相对于Ag / Ag ⁺参比电极）。此外，它揭示了具有133毫安g的可逆放电容量优秀速率能力^-1以1000mA克^-1和121毫安克^-1在2000毫安克^-1，它比那些正交的V更高₂ ø ₅膜（41毫安克^-1以1000mA克^-1和34毫安克^-1在2000毫安克^-1）。水合V ₂ O _5的钠离子存储容量和高倍率性能的显着提高薄膜的主要原因是其较大的层间间距，可以促进Na ⁺的插入/提取，以及V ⁴⁺的存在和氧空位，可以改善电子导电性并减轻体积膨胀引起的应力。