DLP-printed MXene/HFO/PAM hydrogels for integrated microwave absorption and strain sensing

Positively charged HFO and negative MXene were electrostatically assembled. • The interconnected porous Mxene/HFO/PAM hydrogel was precisely fabricated via DLP 3D printing. • The optimized absorber delivers ultrahigh RL min of −55.18 dB and broad EAB of 5.68 GHz. Architecturally engineered multifunctional hydrogels hold great promise for integrated electromagnetic protection and flexible electronics. However, achieving high-performance microwave absorption while maintaining structural flexibility and high-resolution printability remains a significant challenge due to impedance mismatch and unoptimized attenuation networks. Herein, a three-dimensional architectured MXene/HFO/PAM composite hydrogel was fabricated via electrostatic self-assembly and DLP 3D printing, yielding an integrated material system with efficient electromagnetic wave absorption and flexible strain-sensing capabilities. Positively charged HFO nanospheres were uniformly assembled onto negatively charged MXene nanosheets, constructing a hybrid dielectric-magnetic filler with improved interfacial compatibility. Combined with the three-dimensional interconnected porous architecture enabled by DLP printing, the optimized MHH-2 hydrogel achieved an RL min of −55.18 dB and an EAB of 5.68 GHz at a thickness of 2.7 mm. In addition, the integrated conductive framework and robust hydrogel network afforded excellent mechanical flexibility and stable strain-sensing behavior, with rapid response/recovery times of 200/350 ms and reliable motion-monitoring performance. This study offers a promising route toward architecturally engineered hydrogel-based integrated material systems for electromagnetic protection and intelligent sensing. Download: Download high-res image (209KB) Download: Download full-size image