Wave-absorbing Properties of a Cement-based Coating with MnO 2 /Activated Carbon Composite

MnO 2 /activated carbon composite (Mn-ACC) wave absorber was prepared by the reaction between Mn(CH 3 COO) 2 and KMnO 4 on activated carbon. Then, a novel cement based composite absorbing coating (CB-CAC) was prepared by adding the Mn-ACC, manganese zinc ferrite and rubber particles into cement. XRD method was used to analyze the reaction products of the Mn-ACC. The tensile bond strength and the wave absorbing properties of the CB-CACs were also tested. The results showed that the crystallinity of MnO 2 formed in the Mn-ACC was poor. Adding Mn-ACC into the CB-CAC led to first increase and then decrease of the tensile bond strength. The tensile bond strength reached 1.89 MPa with 8.51% of the Mn-ACC. The CB-CACs obtained the optimal absorbing properties with the cement, manganese zinc ferrite, Mn-ACC, rubber particles and H 2 O mass ratio of 7.5׃7.5׃1׃1׃5.5, respectively. The band width of the reflection below -10 dB was up to 8.8 GHz, which accounted for 57.14% of the test band.