Glycine-assisted solution combustion synthesis of NiCo2O4 electromagnetic wave absorber with wide absorption bandwidth

Design of high-performance electromagnetic (EM) wave absorbing materials has been regarded as an effective solution to excessive EM wave interference problem. As a promising candidate, NiCo2O4 absorbers have attracted enormous research attentions. However, currently reported morphology-manipulation synthetic methods of NiCo2O4 absorbers are time-consuming and require high energy consumption, which inhibit their practical applications. Herein, a more facile and cost-effective solution combustion synthesis was utilized to fabricate NiCo2O4 materials. The absorber prepared by using glycine as fuel displayed the best EM wave absorption performance. Impressively, ultra wide absorption bandwidth of 7.44 GHz from 10.56 GHz to 18 GHz could be achieved with relatively thin thickness of 2.1 mm NiCo2O4 sample fabricated in this work displayed the widest effective absorption bandwidth (EAB) among reported NiCo2O4-based EM wave absorbing materials so far. In view of its simple and low-cost synthetic process and excellent EM wave dissipation capacity, NiCo2O4 samples in this work showed great feasibility as practical absorber. In addition, our findings may also provide new sight for facile preparation of other high-performance EM wave absorbers by solution combustion synthesis instead of complex morphology-manipulation routes.