Mehta Sumit Kumar, Padhi Prasenjeet, Wongwises Somchai, Mondal Pranab Kumar
Microfluidics and Microscale Transport Processes LaboratoryDepartment of Mechanical Engineering, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India.
Fluid Mechanics, Thermal Engineering and Multiphase Flow Research Laboratory (FUTURE), Department of Mechanical Engineering, Faculty of Engineering, King Mongkut's University of Technology Thonburi (KMUTT), Bangmod, Bangkok 10140, Thailand.
Langmuir. 2024 Sep 3;40(35):18750-18759. doi: 10.1021/acs.langmuir.4c02557. Epub 2024 Aug 20.
Blue energy generation in nanochannels based on salinity gradients is currently the most promising method in the area of nonconventional energy production. We used a semidiluted pure sodium carboxymethylcellulose (NaCMC)-KCl aqueous solution to study the characteristics of blue energy generation within a charged nanochannel. We solve the corresponding equations for ionic transport using a numerical technique based on the finite element method. Our analysis focused on the electric double layer (EDL) potential field, open circuit current, diffuse potential, electric conductance, maximum generated pore power, and maximum energy conversion efficiency by varying concentrations of the salt in the left-side reservoir and the bulk polyelectrolyte. The results indicate that as the polyelectrolyte concentration increases, the extent of EDL overlap considerably reduces. With an increase in polyelectrolyte concentration, the open circuit current increases, while the diffuse potential reduces. It was observed that both electrical conductance and maximal pore power improve considerably with higher polyelectrolyte concentrations. Interestingly, our modeling framework demonstrates a power density substantially higher (up to 16.31 W/m) than earlier configurations and surpasses the established commercial limit (5 W/m). Furthermore, our findings reveal that the reservoir salt concentration significantly affects the rate of decline in the maximum energy conversion efficiency as the polyelectrolyte concentration increases. The research paves the way for the development of high-power-density devices with several practical applications.
基于盐度梯度在纳米通道中产生蓝色能量是目前非常规能源生产领域最具前景的方法。我们使用半稀释的纯羧甲基纤维素钠（NaCMC）-氯化钾水溶液来研究带电纳米通道内蓝色能量产生的特性。我们使用基于有限元方法的数值技术求解离子输运的相应方程。通过改变左侧储液器中盐的浓度和本体聚电解质，我们的分析集中在双电层（EDL）电位场、开路电流、扩散电位、电导率、最大产生的孔隙功率和最大能量转换效率上。结果表明，随着聚电解质浓度的增加，双电层重叠程度显著降低。随着聚电解质浓度的增加，开路电流增加，而扩散电位降低。据观察，较高的聚电解质浓度会使电导率和最大孔隙功率都显著提高。有趣的是，我们的建模框架显示功率密度比早期配置显著更高（高达16.31 W/m），并超过了既定的商业极限（5 W/m）。此外，我们的研究结果表明，随着聚电解质浓度的增加，储液器盐浓度会显著影响最大能量转换效率的下降速率。该研究为具有多种实际应用的高功率密度器件的开发铺平了道路。
