Abstract Capacitive desalination (CDI) has aroused much attention due to its advantages of low energy consumption and environmental compatibility. However, typical CDI processes display limited efficiency. In this work, one-dimensional V2O5 with nanocuboid structure was prepared with MXenes(V2C) precursor for the first time, which has high adsorption capacity, structure stability and fast ion diffusion ability. The as-synthesized V2O5 electrode achieved a salt adsorption capacity(SAC) of 55.2 mg NaCl g−1 V2O5 under optimized conditions with a constant current density of 30 mA g−1, a voltage range from −0.6 to 1.2 V, and an initial solution of 500 mg L−1 NaCl. Furthermore, from the comprehensive analysis of mechanism, due to the high conductivity and low charge transfer resistance of V2O5 electrode, it reduces the energy loss of the resistance during desalination. A particularly low energy consumption of 0.27 kWh kg−1-NaCl is reached when the operation is carried out successfully at low voltage range, indicating the advantages of energy saving and high efficiency. Therefore, V2O5 is an attractive and promising electrode material, which exhibits the potential of pseudocapacitive materials with certain structure for practical CDI application in future and inspires us to have a deep insight into the effect of morphology on the properties.

中文翻译：

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从 V2C MXene 原位形成均匀的 V2O5 纳米长方体作为电容去离子电极，具有更高的结构稳定性和离子扩散能力

摘要 电容式海水淡化（CDI）以其低能耗和环境兼容等优点引起了人们的广泛关注。然而，典型的 CDI 过程显示出有限的效率。本工作首次采用MXenes(V2C)前驱体制备了具有纳米长方体结构的一维V2O5，其具有高吸附容量、结构稳定性和快速离子扩散能力。合成的 V2O5 电极在优化条件下实现了 55.2 mg NaCl g-1 V2O5 的盐吸附容量（SAC），恒定电流密度为 30 mA g-1，电压范围为 -0.6 至 1.2 V，初始500 mg L-1 NaCl 的溶液。此外，从机理综合分析，由于 V2O5 电极的高电导率和低电荷转移电阻，它减少了脱盐过程中电阻的能量损失。在低压范围内成功运行时，能耗特别低，达到0.27 kWh kg-1-NaCl，具有节能高效的优点。因此，V2O5 是一种有吸引力且有前途的电极材料，它展示了具有一定结构的赝电容材料在未来实际 CDI 应用中的潜力，并激励我们深入了解形态对性能的影响。