Wang Sha, Sun Zhe, Ahmad Mehraj, Miao Mengyu
Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China.
International Innovation Center for Forest Chemicals and Materials, Nanjing Forestry University, Nanjing 210037, China.
Int J Mol Sci. 2024 Dec 9;25(23):13226. doi: 10.3390/ijms252313226.
Two-dimensional (2D) nanofluidic channels are emerging as potential candidates for harnessing osmotic energy from salinity gradients. However, conventional 2D nanofluidic membranes suffer from high transport resistance and low ion selectivity, leading to inefficient transport dynamics and limiting energy conversion performance. In this study, we present a novel composite membrane consisting of porous MXene (PMXene) nanosheets featuring etched nanopores, in conjunction with cellulose nanofibers (CNF), yielding enhancement in ion flux and ion selectivity. A mild HO oxidant is employed to etch and perforate the MXene sheets to create a robust network of cation transportation nanochannels that effectively reduces the energy barrier for cation transport. Additionally, CNF with a unique nanosize and high charge density further enhances the charge density and mechanical stability of the nanofluidic system. Under neutral pH and room temperature, the PMXene/CNF membrane demonstrates a maximum output power density of 0.95 W·m at a 50-fold KCl gradient. Notably, this represents a 43% improvement over the performance of the pristine MXene/CNF membrane. Moreover, 36 nanofluidic devices connected in series are demonstrated to achieve a stable voltage output of 5.27 V and power a calculator successfully. This work holds great promise for achieving sustainable energy harvesting with efficient osmotic energy conversion utilization.
二维（2D）纳米流体通道正成为利用盐度梯度渗透能的潜在候选者。然而，传统的二维纳米流体膜存在高传输阻力和低离子选择性的问题，导致传输动力学效率低下，并限制了能量转换性能。在本研究中，我们展示了一种新型复合膜，它由具有蚀刻纳米孔的多孔MXene（PMXene）纳米片与纤维素纳米纤维（CNF）组成，可提高离子通量和离子选择性。采用温和的HO氧化剂对MXene片进行蚀刻和穿孔，以创建一个强大的阳离子传输纳米通道网络，有效降低阳离子传输的能量势垒。此外，具有独特纳米尺寸和高电荷密度的CNF进一步提高了纳米流体系统的电荷密度和机械稳定性。在中性pH值和室温下，PMXene/CNF膜在50倍KCl梯度下表现出0.95 W·m的最大输出功率密度。值得注意的是，这比原始MXene/CNF膜的性能提高了43%。此外，36个串联的纳米流体装置被证明可实现5.27 V的稳定电压输出，并成功为一个计算器供电。这项工作在通过高效渗透能转换利用实现可持续能源收集方面具有巨大潜力。
