By Bhavna KavetiAug 18 2022Reviewed by Susha Cheriyedath, M.Sc. Although implanted medical devices have improved health monitoring systems, they lack stability, biocompatibility, and miniaturized power sources. A salinity gradient can serve as an efficient power source in these miniaturized systems.
Related StoriesUsing saline gelatin hydrogels as solid electrolytes facilitated the in vivo application of the assembled membrane. Furthermore, the reinforcing two-dimensional MXene sheets with one-dimensional NBC nanofibers resulted in a power density of 2.58 watts per square meter under a 100-fold concentration gradient of the solid electrolyte.
The traditional batteries used in implanted medical devices raise a safety concern in terms of toxic materials used in the construction and the risk of leakage. Although recent innovations in implanted medical devices led to the development of smart, lightweight, and biocompatible devices, acid/alkaline electrolytes induce safety issues, including inflammation and foreign body reactions.
MXene is a promising material for developing a nanofluidic osmotic power generator. Moreover, the osmotic membranes based on stacked MXene nanosheets have a confined space, acting as nanofluidic channels for ion transport. However, the narrow ion channels cause a high ion permeation energy barrier, limiting the ion flux. Thus, a balance between ion selectivity and membrane permeability is highly desirable for efficient energy generation.
The 2D MXene nanosheets were reinforced with 1D NBC nanofibers to induce space charge. Moreover, the surface and space charges of these hybrid membranes maintained high ion selectivity and enhanced ion flux. Additionally, the output performance of the assembled membranes was optimized based on the content of NBC nanofibers.
Varying the nanofibers' content helped optimize the power density in NBC/MXene membrane. Reinforcing MXene nanosheets with 50% weight content of NBC nanofibers helped achieve the power density of 5.3 watts per square meter under the salt gradient concentration of 0.5 moles/0.01 moles.