Oxygen vacancy mediated polymerization of pyrrole on MoO3 to construct dielectric nanocomposites for electromagnetic waves absorption application

Transition metal oxides (TMOs) with tunable electronic structures and low cost have gained much attention for various applications. However, rational development of TMOs-based electromagnetic waves (EMW) absorbers is still a challenge due to their inherent weak conductivity and loss capacity. Here, we report a delicate oxygen vacancy mediated compounding strategy that the oxygen vacancy can improve the struc-tural properties of molybdenum trioxide (MoO3) to direct the in-situ polymerization of pyrrole, con-structing the oxygen vacancy-containing o-MoO3/polypyrrole (o-MoO3/PPy) composites. With the abundant active species aroused from oxygen vacancy and PPy via this design, the great electrical conductivity and excellent dielectric loss capability are simultaneously displayed in o-MoO3/PPy composites. Therefore, the outstanding EMW absorption performance is found at optimized o-MoO3/PPy1, achieving a wide absorption bandwidth of 6.26 GHz, which is remarkably enhanced compared to o-MoO3. This work will provide the valuable strategy for the development of TMOs-based materials for efficient EMW absorption.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

In this study, a delicate oxygen vacancy mediated compounding strategy was reported to improve the structural properties of molybdenum trioxide (MoO3) and construct oxygen vacancy-containing o-MoO3/polypyrrole (o-MoO3/PPy) composites. These composites exhibited excellent electrical conductivity and dielectric loss capability, resulting in outstanding electromagnetic wave (EMW) absorption performance. The optimized o-MoO3/PPy1 sample achieved a wide absorption bandwidth of 6.26 GHz, significantly enhanced compared to o-MoO3. This work provides a valuable strategy for the development of efficient EMW absorption materials based on transition metal oxides.