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Herein, a MnFe2O4/RGO knitted fabric derived from manganese waste was constructed by a simple in-situ assembled coating method, involving the incorporation of Graphene Oxide (GO) and manganese ferrite nanoparticles on polyester fabric, followed reducing by hydrazine hydrate. The reuse of manganese waste from the preparation of GO can reduce chemical waste emissions and endow the absorption performance. The coated particles possess certain magnetism can be attracted and securely collected in seconds, which is convenient for recycling. This fabric gives well microwave absorption with the maximum reflection loss (RL) of −58.6 dB at 9.1 GHz by a thickness of 1.9 mm. In addition, this fabric presents high stable strain sensing under 1000 stretching and bending cycles. Meanwhile, the resistance-deformation-velocity relationship is provided based on the structure, for the analysis of electromechanical behaviors. Moreover, the fabric has the capability for temperature sensing (TCR=−0.738%/°C), and fire alarm. As such, this fabric can be promising alternatives for a wide application on motion and temperature sensing, microwave blocking.

Planar frequency selective surface (FSS) fabrics with grids, strips or patches by simple methods of patching, embroidery, clipping and carving were fabricated. The periodic structures, laminated structures, processing method and materials pertaining to the electromagnetic shielding behaviors were investigated. Firstly, equivalent circuit and electromagnetic (EM) shielding behavior of basic frequency selective structure units and complex fretwork structure were provided, involving the decoupling of complex fretwork structure. In addition, various laminating structures of SPs and SGs were determined, one of superposition of SPs and SGs provides a SE peak of 40.2 dB (average SE of 25.1 dB in the whole frequency domain), the other presents a SE peak of 27.1 dB (average SE of 19.1 dB in the whole frequency regime). Furthermore, tunable selective electromagnetic shielding by a simple mechanical way was provided, which can realize a tunable SE peak varying from 730 MHz to 1580 MHz. This work might provide a perspective for the assemble and analytical approximation of FSS fabrics for scientists and engineers in this cross-disciplinary field.

Disposable face towel derived amorphous carbon prepared by annealing for broad and exacting applications in electromagnetic shielding, electrical heating, etc. This mat with 3D conductive network formed by nonwoven viscose fiber structure gives an outstanding electromagnetic shielding performance of 30 dB and 8161 dB/(g/cm2) at a thickness of 0.168 mm in the frequency range of 0.3–3.0 GHz. In addition, the as prepared mat presents excellent temperature & strain sensing with exceptional sensitivity (BS = 5.5%), and favorable flexibility (1000 bending cycles without fracture). Moreover, the mat provides well Joule heating performance, and the heating temperature can reach over 60°C in 32 seconds under 0.25 A current. More interestingly, the mat shows excellent fire alarm with a fast response (84 ms) and high operating temperature (>500°C). This method provides a simple and low-cost new method for radiation protection, temperature detection, fire alarm and other fields.