Interfacial Super‐Assembly of T‐Mode Janus Porous Heterochannels from Layered Graphene and Aluminum Oxide Array for Smart Oriented Ion Transportation

Abstract

Salinity gradient energy existing in seawater and river water is a sustainable and environmentally energy resource that has drawn significant attention of researchers in the background of energy crisis. Nanochannel membrane with a unique nano‐confinement effect has been widely applied to harvest the salinity gradient energy. Here, Janus porous heterochannels constructed from 2D graphene oxide modified with polyamide (PA‐GO) and oxide array (anodic aluminum oxide, AAO) are prepared through an interfacial super‐assembly method, which can achieve oriented ion transportation. Compared with traditional nanochannels, the PA‐GO/AAO heterochannels with asymmetric charge distribution and T‐mode geometrical nanochannel structure shows directional ionic rectification features and outstanding cation selectivity. The resulting heterochannel membrane can achieve a high‐power density of up to 3.73 W m−2 between artificial seawater and river water. Furthermore, high energy conversion efficiency of 30.3% even in high salinity gradient can be obtained. These achievable results indicate that the PA‐GO/AAO heterochannels has significant potential application in salinity gradient energy harvesting.

Extraction of Evaporation-Driven Electrokinetic Streaming Potential from V2O5 Nanochannels through Secondary Sources

“…Under these conditions, the concentration of the ionic species inside the nanofluidic channel is determined by the surface charges of the V 2 O 5 sheets and not by the concentration of the reservoir. The negative surface charges of the V 2 O 5 nanochannels preferentially allow the passage of H 3 O + ions. − The continuous uphill flow of charged species driven by a combination of capillary forces and evaporation from the membrane surface develops a constant potential difference between the two electrodes (Figure d). ,, To rule out the effect of electrode reaction on potential generation, the experiment was repeated by replacing Cu electrodes with silver wires. As expected, the application of silver electrodes did not vary the output current and voltage values (Figure S5).…”

Super-assembly of freestanding graphene oxide-aramid fiber membrane with T-mode subnanochannels for sensitive ion transport

“…19 In addition, GO membranes bearing well-aligned interlayer nanochannels and well-defined physicochemical properties 20 promise fast proton transport 21 and energy conversion. 22 Therefore, they have great potential in the construction of nanofluidic devices for selective ion transport. 23…”

Interfacial Assembly of Functional Mesoporous Carbon‐Based Materials into Films for Batteries and Electrocatalysis

“…Also, our group used this method to synthesized PA(polyamide)‐GO/AAO for ion transportation (Figure 6f,g). [ 96 ] However, there are not many reports about synthesizing mesoporous carbon‐based materials first and then using solvent casting to prepare films. The synthesis process of ordered mesoporous carbon material is complex, combined with solvent casting will make whole process more complex.…”