The Korea Electrotechnology Research Institute research team has developed a technology to print high-resolution 3D microstructures using a new material known as MXene.
MXene is a two-dimensional nanomaterial composed of alternating metal and carbon layers. MXene possesses high electrical conductivity and electromagnetic shielding capabilities, and its properties make it easy to combine with various metal chemicals, drawing attention in multiple fields such as high-efficiency batteries and electromagnetic shielding.
To apply MXene in the 3D printing field, a separate additive (binder) is required, and there were challenges in adjusting the optimal ink viscosity (concentration) for printing. If the supply of MXene is too high, the high-concentration ink clogs the pipette nozzle, while reducing the amount significantly limits the ability to print the desired structures.
Seol Seung-gwon, a principal researcher at the Korea Electrotechnology Research Institute, employed a unique 'Meniscus' method. The meniscus occurs when droplets are pressed or pulled with a certain pressure, allowing the droplets to burst without breaking due to capillary action, forming a curved surface on the exterior wall.
The research team created 3D printing nano ink that can print high-resolution microstructures at low viscosity by dispersing MXene, which possesses high hydrophilicity, in water without a binder.
The printing principle is simple. First, when ink is sprayed from the 3D printer nozzle, nanomaterials, including MXene, are expelled using the meniscus as a pathway. At this point, the solvent (water) rapidly evaporates from the meniscus surface, while strong attractive forces (van der Waals forces) act internally, causing the nanomaterials to bond together. By continuously moving the nozzle and repeating this process, electrically conductive 3D microstructures are formed.
The technology developed by the research team maximally utilizes the properties of MXene without additives. The printing resolution is 270 times higher than existing technology, reaching 1.3 µm (micrometers).
Seol Seung-gwon noted, "We put a lot of effort into optimizing the concentration conditions of the MXene ink and precisely analyzing various parameters that could arise during the printing process," and added, "Our technology is the world's first achievement that allows for the creation of high-strength, high-precision 3D microstructures utilizing the advantages of MXene without separate additives or post-processing steps."
References
Small(2025), DOI : https://doi.org/10.1002/smll.202409198