From Waste to Functional Materials: A Multifunctional Electromagnetic Interference Shielding Composite from Waste Rock Wool

Abstract

Electromagnetic interference (EMI) shielding materials are effective in eliminating unwanted electromagnetic interference and reduce the potential harm to human health. Among them, the EMI shielding materials fabricated from wastes but with multiple functions are particularly attractive. However, it is always a great challenge to integrate multiple functions into one EMI shielding material, especially when using the wastes as raw materials. Here, a multifunctional EMI shielding composite was fabricated from waste rock wool, which is one of the fast-growing solid wastes in the world. The waste rock wool was converted into a valuable EMI material by simply dip-coating the rock wool into a graphene oxide aqueous dispersion and a following chemical reduction by hydrazine hydrate. The obtained rock wool/reduced graphene oxide (RW-rGO) composites showed excellent EMI shielding performance (>25 dB) and good hydrophobicity (water contact angle >130°). Moreover, the RW-rGO composites exhibit good thermal insulation and fire-retardant ability. We believe that the strategy for fabricating RW-rGO composites not only provides an effective way to solve the problem of waste rock wool pollution but also can promote the large-scale manufacturing of multifunctional EMI shielding materials.

Extremely high-efficiency solar steam generation, robust and scalable photothermal evaporator based on ZIF-67@MXene/rGO decorated rock wool

“…To overcome this issue, recycling RW waste into functional materials for sustainable development could involve turning it into higher value products such as heavy metal-ion absorbents, 23 filter beds, 24 used for oil–water separation, 25 photocatalysis 26 and electromagnetic interference shielding. 27 Recent reports on RW decorated with thermally insulating polymers of Cl − doped poly(3,4-ethylenedioxythiophene) as the photothermal absorber, demonstrate relatively poor solar steam generation performance with evaporation rate and efficiency of 1.64 kg m −2 h −1 and ∼80%, respectively. 28 However, most 3D designs of evaporators so far, are limited reports on evaporation rate and salt fouling resistance performance in highly concentrated saline solution (≥20 wt% NaCl).…”