Ruhao Yang, Danfeng Zhang, Ningpu Li, Haiyan Zhang, Guoxun Zeng, Di Lan
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引用次数: 0
Abstract
Self-assembly of graphene nanosheets and conversion of biomass materials are two popular strategies in the field of microwave absorption for the development of three-dimensional (3D) foam structures. However, the complexity of their synthetic routes, which involve time-consuming and costly procedures, presents challenges in bridging the gaps between scientific research and practical application. In this study, we employ a nitrate-assisted polymer-bubbling strategy for the synthesis of 3D foamy composites. Solid-state hybrids consisting of metal (i.e., Ce and Co) nitrates and polyvinylpyrrolidone (PVP) serve as the precursors in a one-step annealing treatment. Intriguingly, in the presence of both Ce3+ and Co2+ within these precursors, the nitrogen-doped carbon nanotubes (NCNTs), with metallic Co nanoparticles encapsulated at their tips, are locally grown on the surface of the resultant pyrolyzed products. By augmenting the feeding amount of Co2+ quantitatively, not only are the loading amount and length of NCNTs synchronously reduced, but also there exist disparities in the EM parameters for pyrolyzed products, resulting in their distinguishable EM absorption performances. When the feeding amount of Co2+ is moderate, the sample, denoted as CeO2/C/Co@NCNT-2, demonstrates admirable EM absorption characteristics, including an exceptional minimum RL intensity of − 56.2 dB (2.3 mm) and a spectacular maximum EAB value of 7.3 GHz (2.7 mm), which are owed to the positive interference cancellation phenomenon, favorable multiple-reflection behavior of incident EM waves, and the collaborative contributions of dielectric-magnetic dual losses. Additionally, it also showcases charming characteristics in the aspects of waterproof functionality and thermal insulation.
期刊介绍:
The Chemical Engineering Journal is an international research journal that invites contributions of original and novel fundamental research. It aims to provide an international platform for presenting original fundamental research, interpretative reviews, and discussions on new developments in chemical engineering. The journal welcomes papers that describe novel theory and its practical application, as well as those that demonstrate the transfer of techniques from other disciplines. It also welcomes reports on carefully conducted experimental work that is soundly interpreted. The main focus of the journal is on original and rigorous research results that have broad significance. The Catalysis section within the Chemical Engineering Journal focuses specifically on Experimental and Theoretical studies in the fields of heterogeneous catalysis, molecular catalysis, and biocatalysis. These studies have industrial impact on various sectors such as chemicals, energy, materials, foods, healthcare, and environmental protection.