Abstract Searching for ultralight microwave absorber with good heat-insulating property is highly desirable to fulfill the technical requirement of modern society. Herein, the two-dimension (2D) graphene-like porous carbon nanosheets (GPCN) derived from the waste pomelo peel were developed. The preparation is performed by a facile hydrothermal process with synergistic usage of HAc and H2O2. Interestingly, the thickness and porosity of GPCN can be readily regulated by adjusting addition amount of the reagents. The related synthetic mechanism is investigated in depth. Compared with traditional graphene, the fabrication strategy of GPCN possesses many advantages, such as low cost, high yield and ease of production. The results show that GPCN presents superior thermal insulation and microwave absorption properties. The heat-insulating property is comparable to commercial products, e.g. polyurethanes (PU), nickel foam (NF), carbon foam (CF). The strong microwave absorption intensity of −56.4 dB and bandwidth of 6.4 GHz is achieved under ultralow filling ratio of 4 wt%. Moreover, the density of assembled 3D macroscopically product is merely 0.01 g/cm−3. The excellent performance should be attributed to the unique 2D morphology and high porosity of GPCN. Our work paves a new way for developing porous carbon nanosheet from sustainable biomass as heat-insulating ultralight microwave absorber.

中文翻译：

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生物质衍生的类石墨烯多孔碳纳米片对超光微波吸收和优异的热红外性能

摘要 寻找具有良好隔热性能的超轻微波吸收体是满足现代社会技术需求的迫切需要。在此，开发了源自​​废柚皮的二维（2D）类石墨烯多孔碳纳米片（GPCN）。该制备是通过简单的水热工艺与 HAc 和 H2O2 的协同使用进行的。有趣的是，GPCN 的厚度和孔隙率可以很容易地通过调节试剂的添加量来调节。相关的合成机理进行了深入研究。与传统石墨烯相比，GPCN的制备策略具有成本低、良率高、易于生产等诸多优点。结果表明，GPCN具有优异的隔热和吸波性能。隔热性能可与商业产品相媲美，例如聚氨酯 (PU)、泡沫镍 (NF)、碳泡沫 (CF)。在4 wt%的超低填充率下实现了-56.4 dB的强微波吸收强度和6.4 GHz的带宽。此外，组装的 3D 宏观产品的密度仅为 0.01 g/cm-3。优异的性能应归功于GPCN独特的二维形态和高孔隙率。我们的工作为从可持续生物质开发多孔碳纳米片作为隔热超光微波吸收剂铺平了道路。组装的 3D 宏观产品的密度仅为 0.01 g/cm−3。优异的性能应归功于GPCN独特的二维形态和高孔隙率。我们的工作为从可持续生物质开发多孔碳纳米片作为隔热超光微波吸收剂铺平了道路。组装的 3D 宏观产品的密度仅为 0.01 g/cm−3。优异的性能应归功于GPCN独特的二维形态和高孔隙率。我们的工作为从可持续生物质开发多孔碳纳米片作为隔热超光微波吸收剂铺平了道路。