西安工业大学等《JMST》：柚子皮为原料制备超轻碳气凝胶，用于微波吸收和红外隐身功能。

图1.CN/rGO气凝胶的合成路线。

图2. SEM images of (a, b) CN/rGO-180, (c, d) CN/rGO-220, (e, f) CN/rGO-260, (g, h) CN/rGO-300; (i) The magnified SEM image; (j) TEM and (k) HRTEM images of CN/rGO-260; (l) The photograph of free-standing CN/rGO aerogel.

图3. (a) XRD patterns and (b) Raman spectra of all CN/rGO aerogels; (c) XPS total survey of CN/rGO-260, and high-resolution spectrum of (d) C1s, (e) O 1s, and (f) N1s.

图4. (a) Real permittivity, (b) imaginary permittivity, (c) complex permeability and (d) dielectric/magnetic loss tangent of aerogels.

图5. 3D RL contours versus frequency and thickness: (a) CN/rGO-180, (b) CN/rGO-220, (c) CN/rGO-260 and (d) CN/rGO-300. RL curves of (e) CN/rGO-220 and (f) CN/rGO-260 at given thicknesses.

图6. Probable microwave absorption mechanism of CN/rGO-260 aerogel.

图7. (a-f) Thermal infrared images of CN/rGO-260 and typical commercial thermal insulation materials PS, PU, PE at different heating times. (g) Scheme of CN/rGO-260, PS, PU and PE placed on the heating platform. (h) Surface temperature vs time curves. (i) Schematic illustration of the heat transfer mechanism of CN/rGO-260 aerogel.

在这项研究中，我们通过双向冷冻技术和热处理工艺，成功地从生物质SPC和GO中制备出了碳气凝胶（CN/rGO）。得到的 CN/rGO气凝胶由长程有序层状结构和相互连接的桥层组成。通过调节SPC的含量可以有效地调节层状层的距离。在最佳添加剂含量为260mg时，制备的CN/rGO气凝胶显示出优异的微波吸收性能，在填料含量为4wt.%的超低条件下，RLmin为-63.0dB，有效吸收带宽为7.0GHz。优异的性能归功于连续的三维互连网络，它同时确保了最佳的阻抗匹配和有效的衰减能力。此外，气凝胶还具有与商业产品相当的隔热性能。这项工作将为开发低成本、轻质、环保的碳气凝胶开辟新的途径，使其未来在微波吸收和红外隐身领域得到实际应用。