Development of electromagnetic microwave absorbers in cementitious materials

With the wide application of wireless technology, the problem of electromagnetic microwave (EMW) radiation and pollution in building space is becoming more and more serious. Therefore, it is great importance to design and prepare EMW absorbing cementitious materials. Based on the EMW absorption mechanism, the EMW absorbing cementitious materials are divided into three groups according to dielectric loss, magnetic loss and dielectric/magnetic loss coupling in this review. In addition, the preparation, structure and performance of cutting-edge EMW absorbing cementitious materials are reported as the highlights. The effects and optimization mechanisms of EMW absorber on the improvement/modification of cementitious materials are comprehensively summarized and objectively analyzed. More significantly, we emphasize the existing challenges for EMW absorbing cementitious materials and offer a lookout of the future research directions.