Lightweight 3D-printed chitosan/MXene aerogels for advanced electromagnetic shielding, energy harvesting, and thermal management

This study focuses on the fabrication of 3D-printed chitosan/Ti₃C₂T_x-MXene aerogels with varying MXene concentrations (1, 2, 5, and 10 wt%) using the direct ink writing (DIW) method. The inks were freeze-dried to form aerogels, and FTIR and XRD analyses confirmed interactions between chitosan and MXene molecules, leading to increased spacing between MXene nanosheets. Rheological testing showed improved shear-thinning behavior, enhancing printability. A higher MXene content boosted the electrical conductivity, dielectric properties, and electromagnetic interference (EMI) shielding effectiveness, with the 10 wt% MXene aerogel achieving an EMI shielding effectiveness of 27 dB. The thermal conductivity initially decreased but later increased with higher MXene concentrations. Mechanical tests indicated enhanced Young's modulus and tensile strength with more MXene, but the elongation at break decreased. The printed aerogels were used in a Triboelectric Nanogenerator (TENG), showing an increase in output voltage from 22 V for pure chitosan aerogels to 110 V for 2 wt% MXene, with a slightly lower increase in current. However, exceeding 2 wt% MXene led to reduced performance. This study highlights the potential of printed aerogels for energy harvesting, EMI shielding, and thermal insulation applications.