ZIF-67/CMC-derived 3D N-doped hierarchical porous carbon with in-situ encapsulated bimetallic sulfide and Ni NPs for synergistic microwave absorption

Abstract

The development of MOF and biomass-derived functional materials has made outstanding contribution to the remediation of electromagnetic pollution; however, the deigned synthesis of microwave absorbers with synergistic transformation of MOF and biomass components still remains challenging. Herein, we report an in situ sulfuration strategy for the rational construction of CoxSy/NixSy and Ni NPs embedded in N-doped 3D porous carbons (N-Ni-CoxSy/NixSy@C) through controllable sol–gel assembly and carbonization processes employing ZIF-67 and CMC as raw materials. The results showed that defects induced by N doping and Ni NPs, CoxSy/NixSy encapsulation synergistically promoted the impedance matching in the composites. Consequently, when the filler content was 25%, the minimum reflection loss value at 11.7 GHz reached −48.3 dB and the effective absorption bandwidth beyond 3.95 GHz. By virtue of the easy-to-handle assembly process of ZIF-67 and CMC, this designed synthesis method might be potentially promising for up-scale preparation of excellent electromagnetic wave absorbers.