Synthesis of Porous 3D Fe/C Composites from Waste Wood with Tunable and Excellent Electromagnetic Wave Absorption Performance

被引：103

作者：

Lou, Zhichao ^{[1
,2
]}

Li, Yanjun ^{[1
]}

Han, He ^{[1
]}

Ma, Huanhuan ^{[1
]}

Wang, Lian ^{[1
]}

Cai, Jiabin ^{[1
]}

Yang, Lintian ^{[1
]}

Yuan, Chenglong ^{[1
]}

Zou, Jing ^{[1
]}

机构：

[1] Nanjing Forestry Univ, Coll Mat Sci & Engn, 159 Longpan Rd, Nanjing 210037, Jiangsu, Peoples R China

[2] Southeast Univ, Sch Biol Sci & Med Engn, Jiangsu Key Lab Biomat & Devices, State Key Lab Bioelect, 2 Sipailou Rd, Nanjing 210096, Jiangsu, Peoples R China

来源：

ACS SUSTAINABLE CHEMISTRY & ENGINEERING | 2018年 / 6卷 / 11期

基金：

中国博士后科学基金; 中国国家自然科学基金;

关键词：

Pyrolysis; Magnetic biochar; Electromagnetic wave absorption; Electromagnetic interference shielding; Composite; AT-C MICROSPHERES; MICROWAVE-ABSORPTION; FACILE SYNTHESIS; FE3O4; NANOPARTICLES; IRON-OXIDES; SHELL; REDUCTION;

D O I：

10.1021/acssuschemeng.8b04045

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Here, we synthesized Fe/C composites with different crystal structures (Fe3O4@C, Fe304/Fe@C, or Fe3C(@) by carbonizing iron(III) 2,4-pentanedionate (Fe(acac)(3)) pre-enriched forestry waste wood at different pyrolysis temperatures from 400 to 1000 degrees C. The obtained samples are porous 3D (three-dimensional) biochars inlaid with varied Fe phases. The corresponding EMW absorbing properties are proved to be dependent on the pyrolysis temperature, as well as the resulting crystal structures and graphitization degrees. Among them, Fe3C@C obtained at 1000 degrees C possesses excellent EMW absorbing properties with a minimum RL value of 57.64 dB at 6.92 GHz and a wide response bandwidth of 5.00 GHz covering 6.36-11.36 GHz. This good performance is due to continuous substances of Fe3C covering the inner surface of the conductive biochars, permitting the optimal impedance matching along with the strongest dielectric loss and optimal magnetic loss. Moreover, more defects are generated at 1000 degrees C which act as the dipole center and produce dipole relaxation polarization. The dipole relaxation is proved to be positive for improving the EMW absorbing performance together with the interface polarization between C Fe3C.

引用

页码：15598 / 15607

页数：19

共 37 条

[1] Enhanced microwave absorption in Ni/polyaniline nanocomposites by dual dielectric relaxations [J].