Microwave-assisted reduction of graphene oxide (GO) has been reported to be very effective in producing high-quality reduced graphene oxide (rGO) and its composites. However, either pretreatment (e.g., heating) or an external trigger (e.g., copper wire) is required to initiate the process due to the poor microwave absorption ability of GO. In this work, we report a one-step self-triggered microwave-arcing approach for synthesizing rGO composites (NiCo/rGO) for the first time. Evidenced by permittivity value, the synergic microwave absorption between GO and the metal nitrate salts is found to play an important role in initiating the process. From XRD, Raman, XPS and TEM results, it is proposed that mildly reduced rGO is firstly formed after 10 s, which further enables stronger microwave absorption to facilitate the complete reduction of GO as well as formation of well-crystallized NiCo nanoparticles about 10 nm after 90 s. The as-synthesized product shows a minimum refection loss value of − 44.48 dB with an absorption bandwidth of 3.66 GHz at 4.5 mm.

据报道，微波辅助还原氧化石墨烯（GO）在生产高质量的还原氧化石墨烯（rGO）及其复合材料方面非常有效。然而，由于GO对微波的吸收能力差，因此需要预处理（例如加热）或外部触发器（例如铜线）来启动该过程。在这项工作中，我们首次报道了一种一步一步自触发微波电弧合成rGO复合材料（NiCo / rGO）的方法。由介电常数值证明，GO和金属硝酸盐之间的协同微波吸收被发现在引发过程中起重要作用。根据X射线衍射，拉曼光谱，XPS和TEM结果，建议在10 s后首先形成轻度还原的rGO，这进一步使微波吸收更强，以促进GO的完全还原以及在90 s后约10 nm处形成结晶良好的NiCo纳米颗粒。合成后的产品在4.5 mm处的最小吸收损耗值为-44.48 dB，吸收带宽为3.66 GHz。