I am working on developing extrusion-based 3D printing inks using oxidized multi-walled carbon nanotubes (oMWCNTs) and MXene (Ti₃C₂Tx). Based on existing studies, graphene oxide (GO) inks typically require concentrations above 8 wt% to achieve good printability and shape retention. However, oMWCNTs and MXene have different dispersion and rheological behaviors.

I would like to ask:

• What would be a reasonable starting concentration range for oMWCNTs and MXene inks in DIW (direct ink writing) printing?
• Are there any key factors (e.g., dispersants, pH adjustments, shear-thinning behavior) that significantly affect their printability?
• If you have experience with high-concentration CNT or MXene-based inks, what challenges did you encounter?

Any insights or references to relevant studies would be greatly appreciated. Thank you!