Multi-element-doped carbons are actively being pursued as efficient lightweight microwave absorbers. In this work, metal, nitrogen and chlorine codoped carbons (metal,N,Cl–C, where metals = Ni, Co, Mn, or Zn) were synthesized through the high-temperature carbonization of polypyrrole doped with hydrochloric acid (PPy-HCl) and prepared in the presence of certain metal chloride salts (NiCl, CoCl, MnCl, or ZnCl). The dielectric parameters and microwave absorption properties of the metal,N,Cl–C composites could be regulated by simply altering the type of metal salt. Compared with N,Cl–C, it was discovered that Co,N,Cl–C and Ni,N,Cl–C possessed higher graphitization degrees, smaller particle sizes and more surface chemical functional groups (metal−N), which significantly improved the conduction loss and polarization loss effects including interfacial polarization and dipole polarization. At a filler ratio of 9.0 wt%, Ni,N,Cl–C displayed a wide effective absorption bandwidth (EAB, RL ≤ −10 dB) of 7.1 GHz at a thickness of 2.5 mm and a minimum reflection loss (RL) of −29.7 dB at 9.7 GHz and 3.5 mm thickness. Similarly, Co,N,Cl–C offered an RL value of −48.2 dB at 11.3 GHz and a thickness of 3.0 mm and an EAB of 6.0 GHz at a thickness of 2.5 mm. These results showcase the advantages of metal,N,Cl–C composites as microwave absorbers.

中文翻译：

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金属掺杂对多元素（金属、N、Cl）掺杂碳复合材料微波吸收性能的影响


人们正在积极寻求将多元素掺杂碳作为高效的轻质微波吸收剂。在这项工作中，通过高温碳化掺杂盐酸的聚吡咯（PPy-HCl）合成了金属、氮和氯共掺杂碳（金属，N，Cl–C，其中金属= Ni，Co，Mn或Zn） ）并在某些金属氯化物盐（NiCl、CoCl、MnCl 或 ZnCl）存在下制备。金属、N、Cl-C复合材料的介电参数和微波吸收性能可以通过简单地改变金属盐的类型来调节。与N,Cl–C相比，Co,N,Cl–C和Ni,N,Cl–C具有更高的石墨化度、更小的粒径和更多的表面化学官能团（金属−N），显着改善了性能。传导损耗和极化损耗效应，包括界面极化和偶极子极化。当填料比例为 9.0 wt% 时，Ni,N,Cl–C 在 2.5 mm 厚度下表现出 7.1 GHz 的宽有效吸收带宽（EAB，RL ≤ -10 dB），最小反射损耗 (RL) 为 - 9.7 GHz 和 3.5 毫米厚度时为 29.7 dB。类似地，Co,N,Cl–C 在 11.3 GHz、厚度为 3.0 mm 时的 RL 值为 -48.2 dB，在厚度为 2.5 mm 时的 EAB 为 6.0 GHz。这些结果展示了金属、N、Cl-C 复合材料作为微波吸收剂的优势。