Zn-ion battery has received researcher's interests for nonflammable and clean aqueous electrolyte, cheap and harmless Zn anode. Cathode material plays a vital role in Zn-ion battery, which can influence its performance directly. Because of suitable layer spacing, V₂O₅ has been considered as a potential cathode material for Zn-ion battery. But its prospect in Zn-ion battery is hindered by low conductivity. To resolve this problem, oxygen defect rich V₂O₅ (O_d-V₂O₅) is synthesized. It possesses perfect stability when served as cathode material in Zn-ion battery. The specific capacity achieves 425 mAh·g⁻¹ at 0.1 ​A ​g⁻¹. Oxygen defect also prompts the separation of electron-hole pairs and makes more electrons participate in photothermal conversion, which boosts photo energy transforms to thermal energy. For O_d-V₂O₅, it shows high photothermal effect efficiency. With O_d-V₂O₅, photothermal membrane is fabricated with electrospinning technique and applied for solar steam generation sea water desalination. Evaporation rate of the membrane reaches 1.29 ​kg ​m⁻² ​h⁻¹ with energy conversion efficiency 88.1% under 1 sun irradiation. The energy efficiency keeps stable after continuous evaporation. In evaporated water, the concentration of Na⁺, K⁺ Ca²⁺ and Mg²⁺ can satisfy the standard of human drinking water. We expect O_d-V₂O₅ has a bright prospect in Zn-ion battery and sea water desalination.

锌离子电池因不易燃、清洁的水性电解质、廉价且无害的锌阳极而受到研究人员的关注。正极材料在锌离子电池中起着至关重要的作用，直接影响其性能。由于适当的层间距，V ₂ O ₅被认为是锌离子电池的潜在正极材料。但其在锌离子电池中的前景受到低电导率的阻碍。为了解决这个问题，合成了富含氧缺陷的V ₂ O ₅ ( O _d -V ₂ O _{5 )。}用作锌离子电池正极材料时具有完美的稳定性。比容量在0.1 A g时达到425 mAh·g ^−1-1。氧缺陷还促使电子-空穴对分离，使更多的电子参与光热转换，从而促进光能向热能的转化。对于O _d -V ₂ O ₅，表现出较高的光热效应效率。以O _d -V ₂ O ₅为原料，采用静电纺丝技术制备光热膜，应用于太阳能蒸汽发电海水淡化。膜的蒸发速率达到1.29 kg m ⁻²  h ⁻¹1个太阳照射下的能量转换效率为88.1%。连续蒸发后能效保持稳定。^{蒸发水中Na +}、K ⁺ Ca ²⁺和Mg ²⁺的浓度可满足人类饮用水的标准。我们预计O _d -V ₂ O ₅在锌离子电池和海水淡化方面具有广阔前景。