Liu Suling, Yao Yongxian, Li Xueqi, Tang Jianfu, Dong Xiaofei, Wang Yaoxing, Yin Ran, Li Jian, Xie Yanjun, Gan Wentao
Key Laboratory of Bio-based Material Science and Technology (Ministry of Education), Northeast Forestry University, Harbin 150040, P. R. China.
Heilongjiang Key Laboratory of Complex Traits and Protein Machines in Organisms, Northeast Forestry University, Harbin 150040, China.
ACS Nano. 2024 Jul 25. doi: 10.1021/acsnano.4c04359.
Light-driven active ion transport discovered in nanomaterials (e.g., graphene, metal-organic framework, and MXene) implicates crucial applications in membrane-based technology and energy conversion systems. However, it remains a challenge to achieve bulk assembly. Herein, we employ the scalable wood as a framework for in situ growth of MoS nanosheets to facilitate light-responsive ion transport. Owing to the aligned and negatively charged wood nanochannels, the MoS-decorated wood exhibits an excellent nanofluidic conductivity of 8.3 × 10 S cm in 1 × 10 M KCl. Asymmetric light illumination creates the separation of electrons and holes in MoS nanosheets, enabling ions to move uphill against a wide range of concentration gradients. As a result, the MoS-decorated wood can pump ions uphill against a 20-fold concentration gradient at a light intensity of 300 mW cm. When the illumination is applied to the opposite side, the osmotic current along the 20-fold concentration gradient can be enhanced to 75.1 nA, and the corresponding osmotic energy conversion power density increases to more than 12.6 times that of the nonilluminated state. Based on the light-responsive behaviors, we are extending the use of MoS-decorated wood as the ionic elements for nanofluidic circuits, such as ion switches, ion diodes, and ion transistors. This work provides a facile and scalable strategy for fabricating light-controlled nanofluidic devices from biomass materials.
在纳米材料（如石墨烯、金属有机框架和MXene）中发现的光驱动主动离子传输在基于膜的技术和能量转换系统中具有重要应用。然而，实现大规模组装仍然是一个挑战。在此，我们采用可扩展的木材作为原位生长MoS纳米片的框架，以促进光响应离子传输。由于木材纳米通道排列且带负电荷，MoS修饰的木材在1×10 M KCl中表现出8.3×10 S cm的优异纳米流体电导率。不对称光照在MoS纳米片中产生电子和空穴的分离，使离子能够逆着广泛的浓度梯度向上移动。结果，MoS修饰的木材在300 mW cm的光强度下可以逆着20倍浓度梯度向上泵送离子。当光照应用于相反一侧时，沿着20倍浓度梯度的渗透电流可以增强到75.1 nA，相应的渗透能量转换功率密度增加到非光照状态的12.6倍以上。基于光响应行为，我们正在扩展将MoS修饰的木材用作纳米流体电路的离子元件，如离子开关、离子二极管和离子晶体管。这项工作为从生物质材料制造光控纳米流体装置提供了一种简便且可扩展的策略。
