Facile fabrication of indium tin oxide/nanoporous carbon composites with excellent low-frequency microwave absorption

The dielectric behavior and microwave absorption (MA) performance of doped semiconductor indium tin oxide (ITO)/nanoporous carbon (NPC) composites were scanned by a combination of simulations and experiments. In this work, designed homogeneous ITO/NPC composites were synthesized for the first time by the direct pyrolysis of In metal-organic framework doped with Sn (In/Sn-MOFs). Precise regulation of the complex permittivity of ITO/NPC was possible by controlling the carrier concentration, which resulted in superior MA performance. In addition, the conductive network of NPC, large surface areas & pore volumes and abundant heterogeneous interface of ITO/NPC were found to be the key aspects for MA performance. When the ratio of Sn/In was 1:9, ITO/NPC-2 exhibited outstanding MA property at low frequency. At 4.57 GHz and 4.10 mm, the maximum RL value of -60.55 dB was reached; while the RL values below -8 dB were found in the low-frequency range of 3.72-5.42 GHz. In addition, a strong reflection loss (RL) of -45.12 dB was obtained at 12.90 GHz and a small thickness of 1.55 mm. This work might provide a convenient and novel method for the construction of low frequency microwave absorbers. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

The dielectric behavior and microwave absorption performance of doped semiconductor indium tin oxide/nanoporous carbon composites were investigated through simulations and experiments, showing that precise regulation of the carrier concentration can lead to superior microwave absorption performance by controlling the complex permittivity. The study also revealed that the conductive network of NPC, large surface areas and pore volumes, and abundant heterogeneous interface of ITO/NPC play key roles in the microwave absorption performance.