天然生物已经进化出各种生物离子通道,以对不同的物理和/或化学刺激做出及时反应。指导构建人工同行,拓展相应应用。它们还显示出克服传统电子设备缺点的有希望的潜力(例如,耗能操作和不利的湿度干扰)。在这里,我们基于Janus双场异质膜构建了一个绿色藻类启发的纳米流体系统(即,J-HM),它可以在水下作为人工视觉平台,通过增强活性离子传输来感知光。J-HM是通过顺序组装的MXene和Cu-HHTP获得的(即,基于2,3,6,7,10,11-六羟基三亚苯基水合物(HHTP)和Cu2+)结构单元之间的反应的金属-有机框架。由于J-HM在光照下的局部热激发和有效的电荷分离所形成的温度梯度和膜内电场,产生热渗和光驱动力,用于从Cu-HHTP到MXene的优先阳离子运输。此外,单向主动传输可以通过浓度梯度下的自扩散来增强。然后,探索了在各种光照条件下相应的水下光感知,与光强度几乎呈线性关系。最后,证明了视觉平台可以实现物体形状,定义,和使用定义的像素化矩阵的距离识别,推动开发基于离子信号传输的传感系统。
Natural organisms have evolved various biological ion channels to make timely responses toward different physical and/or chemical stimuli, giving guidance to construct artificial counterparts and expand the corresponding applications. They have also shown promising potential to overcome disadvantages of traditional electronic devices (e.g., energy-consuming operation and adverse humidity interference). Herein, we constructed a green alga-inspired nanofluidic system based on a Janus dual-field heterogeneous membrane (i.e., J-HM), which can function underwater as an artificial visual platform for light perception through enhanced active ion transport. The J-HM was obtained through sequentially assembled MXene and Cu-HHTP (i.e., a metal-organic framework based on the reaction between 2,3,6,7,10,11-hexahydroxytriphenylene hydrate (HHTP) and Cu2+) building units. Due to the formed temperature gradient and intramembrane electric field caused by the localized thermal excitation and efficient charge separation of J-HM under illumination, thermo-osmotic and photo-driven forces are generated for preferential cation transport from Cu-HHTP to MXene. Furthermore, unidirectional active transport can be enhanced by self-diffusion under a concentration gradient. Then, the corresponding underwater light perceptions at various light illumination conditions are explored, showing nearly a linear correlation with the light intensity. Finally, it is demonstrated that the visual platform can achieve object shape, definition, and distance recognition using a defined pixelated matrix, giving impetus to develop ionic signal transmission based sensing systems.