• The rGO/PAA aerogel achieves synergistic optimization for direct ink writing printing and construction of 0D/2D heterostructures in rGO sheets.
• Optimal reflection loss of −39.86 dB and effective absorption bandwidth (EAB) of 8.36 GHz are obtained with low density of 4.8 mg cm−3.
• Realization of an ultra-broadband metamaterial absorber of 14 GHz EAB at 7.8 mm thickness, across the C, X, and Ku bands.
• The dual-gradient regulation of rheology and dielectric loss enables lightweight, broadband electromagnetic absorption, offering a scalable manufacturing route.