Cement-and-pebble nanofluidic membranes with stable acid resistance as osmotic energy generators

具有抗酸腐蚀的“水泥-鹅卵石”结构纳流体膜用于渗透能转换

Osmotic energy between river water and seawater has attracted interest as a new source of sustainable energy.Nanofluidic membranes in a reverse electrodialysis configuration can capture energy from salinity gradients.However,current membrane materials suffer from high resistances,low stabilities,and low charge densities,which limit their further application.Here,we designed a high-performance nanofluidic membrane using carboxylic cellulose nanofibers functionalized with graphene oxide nanolamellas with cement-and-pebble microstructures and stable skeletons for enhanced ion transmembrane transport.By mixing artificial river water and seawater,the composite membrane achieved a high output power density up to 5.26 W m^(−2).Additionally,the membrane had an excellent acid resistance,which enabled long-term use with over 67 W m^(−2) of power density.The performance of this composite membrane benefited from the mechanically strong cellulose fibers and the bonding between nanofibers and nanolamellas.In this work,we highlight promising directions in industrial waste treatment using energy extracted from chemical potential gradients.

河水与海水之间存在的渗透能是一种新型、可持续的能源,并引起了人们的广泛关注.其中,通过反向电渗析技术,纳流体膜能够从盐度梯度中捕获这种能量.然而,目前的膜材料存在一些不足,例如膜阻过高、稳定性差以及电荷密度低等,这在很大程度上限制了它们的进一步应用.在这项研究中,我们设计了一种高性能的纳米复合膜,该膜采用纤维素为主体并与氧化石墨烯复合,具有类似“水泥-鹅卵石”结构的稳定骨架,有利于增强离子跨膜传输.在人工河水和海水环境中,复合膜的输出功率密度可达5.26 W m^(−2).此外,该膜在质子梯度条件下的功率密度超过67 W m^(−2),且具有良好的耐酸性能,可长期使用.复合膜应用的多样性得益于机械强度高的纤维素与氧化石墨烯纳米结构间的结合作用.在这项工作中,我们展示了利用化学势梯度提取能量并且实现工业废水处理的前景.