Ni3Fe@N-doped carbon nanotubes 3D network induced by nanoconfined symmetry breaking for high-performance microwave absorption, corrosion protection, and pollutant purification

It remains challenging to develop multifunctional electromagnetic wave (EMW) absorbers with anti-corrosion and pollutant purification capabilities suitable for extremely harsh ocean environments. This study exploits symmetry breaking to construct a three-dimensional (3D) network of bamboo-like N-doped carbon nanotubes (NCNT) encapsulated with magnetic Ni3Fe nanocatalysts via facile coordination and catalytic chemical vapor deposition process. The resulting Ni3Fe@NCNT composite demonstrates outstanding EMW absorption performance, anti-corrosion behavior, and adsorption purification function. Its excellent EMW absorption performance, including a minimum reflection loss of −57.3 dB and a maximum effective absorption bandwidth of 6.0 GHz, is achieved by magnetic-dielectric match, inert space platform, and porosity architecture. The Ni3Fe@NCNT composite also shows corrosion resistance and self-cleaning function simultaneously because of the physical shield provided by the intrinsically impermeable, inert NCNT shells and their considerable chemically active site and high porosity. For the first time, the EMW absorber is endowed with cooperative multi-functionalities. Our findings may pave the way to manufacture versatile EMW materials for applications in complicated environments. To tackle microwave pollution accompanied by the booming development of 5G telecommunication devices in complex circumstances, the cutting-edge three-dimensional nanocomposites have been posted significance and exploited. The nanocomposites synergistically hold triple functionalities, including competitive microwave absorption, reliable anticorrosion and admirable adsorption power. This work paves the way to the development of advanced absorbers in extremely humid and contaminative ocean environments. [Display omitted] •Competitive microwave absorbing material with reliable corrosion protection and admirable adsorption purification performance.•3D NCNT network encapsulating Ni3Fe nanoparticle via nanoconfined symmetry breaking strategy through CCVD.•EAB of 6.0 GHz and RLmin of −57.3 dB with filling ratio of 8 wt%.•Long-term anti-corrosion property in corrosive medium (Icorr∼10−8 A cm−2).•Superior adsorption capacity and removal rate of dye solutions (Qe = 773.6 mg g−1).