Yao Bing, Hussain Shabab, Ye Zhizhen, Peng Xinsheng
State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, ERC of Membrane and Water Treatment, MOE, Zhejiang University, Hangzhou, 310027, P. R. China.
Wenzhou Key Laboratory of Novel Optoelectronic and Nanomaterials, Institute of Wenzhou, Zhejiang University, Wenzhou, 325006, P. R. China.
Small. 2023 May;19(18):e2207559. doi: 10.1002/smll.202207559. Epub 2023 Feb 1.
Ion-selective membranes are considered as the promising candidates for osmotic energy harvesting. However, the fabrication of highly perm-selective membrane is the major challenge. Metal-organic frameworks (MOFs) with well-defined nanochannels along functional charged groups show great importance to tackle this problem. Here, a series of dense sodium polystyrene sulfonate (PSS) incorporated MOFs composite membranes (PSS@MOFs) on a porous anodic aluminum oxide (AAO) membrane via in situ anodic electrodeposition process are developed. Benefiting to the novel structural design of the confined Ag layer, PSS@MOFs dense composite membrane with less defects formed. The sulfonated nanochannels of the PSS@MOFs composite membrane provided rapid and selective transport of cations due to the enhanced electrostatic interaction between the permeating ions and MOFs. While osmotic energy conversion, 860 nm thick negatively charged PSS@MOFs composite membrane achieves an ultrahigh cation transfer number of 0.993 and energy conversion efficiency of 48.8% at a 100-fold salinity gradient. Moreover, a large output power of 2.90 µW has been achieved with an ultra-low internal resistance of 999 Ω, employing an effective area of 12.56 mm . This work presents a promising strategy to construct a high-performance MOFs-based osmotic energy harvesting system for practical applications.
离子选择性膜被认为是用于渗透能收集的有前景的候选材料。然而，制备具有高渗透选择性的膜是主要挑战。具有沿功能带电基团的明确纳米通道的金属有机框架（MOF）对于解决这个问题具有重要意义。在此，通过原位阳极电沉积工艺在多孔阳极氧化铝（AAO）膜上制备了一系列包含致密聚苯乙烯磺酸钠（PSS）的MOF复合膜（PSS@MOF）。受益于受限银层的新颖结构设计，形成了缺陷较少的PSS@MOF致密复合膜。PSS@MOF复合膜的磺化纳米通道由于渗透离子与MOF之间增强的静电相互作用而提供了阳离子的快速和选择性传输。在渗透能转换过程中，860 nm厚的带负电的PSS@MOF复合膜在100倍盐度梯度下实现了0.993的超高阳离子转移数和48.8%的能量转换效率。此外，采用12.56 mm²的有效面积，以999 Ω的超低内阻实现了2.90 μW的大输出功率。这项工作提出了一种有前景的策略，用于构建基于MOF的高性能渗透能收集系统以用于实际应用。
