The globally extractable salinity gradient (SG) energy from the mixing of seawater and river water is estimated to be 3% of worldwide electricity consumption. Here we applied carbonized peat moss (CPM) electrodes to a capacitive concentration flow cell that is capable of harvesting SG energy based on the capacitive double layer expansion (CDLE) together with the Donnan potential. The electrodes were made from the visually inexhaustible peat moss by a facile and environmental benign pyrolysis process. With two identical CPM electrodes and a cation-exchange membrane, the cell produced a peak power density of 5.33 W m⁻² and an average power density of 950 mW m⁻², the highest ever reported for CDLE-based techniques, using synthetic seawater (30 g L⁻¹ NaCl) and river water (1 g L⁻¹ NaCl). The excellent performance was a result of the macroporous structure of the CPM electrodes, the assistance of Donnan potential, and the double-channel structure of the cell. This system was durable as it could extract energy from highly saline water (300 g L⁻¹ NaCl) and it still worked well after 100 cycles. This study provides a new method to efficiently and continuously harvest SG energy based on the CDLE without an external charge.

海水和河水混合产生的全球可提取盐度梯度（SG）能量估计占全球用电量的3％。在这里，我们将碳化的泥炭藓（CPM）电极应用于电容性浓度流通池，该池能够基于电容性双层膨胀（CDLE）和Donnan电势来收集SG能量。电极是由一种在视觉上取之不尽，用不竭的泥炭苔制成的，采用的是环境友好的热解工艺。使用两个相同的CPM电极和阳离子交换膜，该电池使用合成海水产生的峰值功率密度为5.33 W m ^-2，平均功率密度为950 mW m ^-2，这是有史以来基于CDLE的技术中最高的（30克L ^-1NaCl）和河水（1 g L ^-1 NaCl）。优异的性能是CPM电极的大孔结构，唐南电势的辅助以及电池的双通道结构的结果。该系统很耐用，因为它可以从高盐度的水（300 g L ^-1 NaCl）中提取能量，并且在100次循环后仍能很好地工作。这项研究提供了一种基于CDLE的高效连续收获SG能量的新方法，而无需外部充电。