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MATERIALS COMMUNICATIONSThe purpose of this Materials Communications section is to provide accelerated publication of important new results in thefields regularly covered by Journal of Materials Research. Materials Communications cannot exceed four printed pages inlength, including space allowed for title, figures, tables, references, and an abstract limited to about 100 words.Solid-state pyrolysis of iron phthalocyanine polymer intoiron nanowire inside carbon nanotube and their novelelectromagnetic propertiesRui Zhao, Yajie Lei, Yingqing Zhan, Fanbin Meng, Kun Jia, Jiachun Zhong, and Xiaobo Liua)Research Branch of Functional Polymer Composites, Institute of Microelectronic & Solid State Electronic,University of Electronic Science and Technology of China, Chengdu 610054, People’s Republic of China(Received 16 October 2010; accepted 17 August 2011)Bulk production of iron nanowire inside carbon nanotubes (CNTs) from iron phthalocyanine (FePc)polymer under 800 °C is presented for the first time. The bis-phthalonitrile was firstly reactedwith iron nanoparticles to produce iron phthalonitrile oligomer, and heat treatments made theformation of CNTs occurred during the carbonization process of FePc polymer at ambient pressurein nitro atmosphere under 800 °C. The iron nanowire inside carbon tubes from the metal Pcpolymer possessed excellent electromagnetic loss and magnetic loss properties.One-dimensional nanoscale materials have attractedgreat attention.1Among them, graphitic carbon nanotubes(CNTs) are one of the most interesting cases because oftheir unique electronic properties and many potentialapplications.2Several methods such as electronic arcdischarge, laser ablation, and chemical vapor deposition(CVD) of small hydrocarbons over metallic catalysts arecommonly used to prepare CNTs.3Among them, the CVDmethod is particularly attractive for the synthesis of alignedCNTs in the gas phase. Controllable solid state pyrolysis oforganometallic precursors has recently emerged as analternative method for preparing carbon nanostructuressuch as CNTs and carbon onions.4In such a process, theorganometallic complexes serve as both the catalyst pre-cursors and as carbon sources, and the pyrolysis is carriedout not in the gas phase but in the solid state at “low”temperatures.Phthalocyanine (Pc) is a planar heterocyclic moleculeof about 1.3 nm diameter having four fused togetherphenyl and pyrrole subunits. The Pc macromolecule isable to coordinate various metal cations (Fe, Ni, Co, etc.)in its center with the four central nitrogen atoms belon-ging to the pyrrolic subunits. With iron, this is called ironphthalocyanine (FeC32H16N8, FePc), which is useful inCNTsynthesis.5However,allthesemethodsneedasupplyof hydrogen to maintain the activity of catalysts during thehigh-temperature process (800–1300 °C). Furthermore,bulk synthesis of CNTs from a simple, controllable, andlow-cost method is still a critical target in scientific andindustrial research. To conquer the shortages of the lowmolecular weight Pc as carbon source, the use of Pcpolymer, which has extremely good thermal propertiesand high char yields upon thermal treatment to elevatedtemperatures,6as only carbon source for the formation ofCNTs in the solid phase is an intriguing idea.In this work, bulk synthesis of iron nanowire insideCNTs from FePc polymer in nitro atmosphere under800 °Cispresentedforthefirsttime.Theexcellentvolumeelectrical resistivity of the iron nanowire inside CNTs is9.0 ? 10?3X?cm?1. The iron nanowire inside carbontubes from the metal Pc polymer possessed excellentelectromagnetic loss properties, and the presence of themagnetic nanoiron inside CNTs provided the materialswith novel magnetic loss properties.Ten-gram 4, 49-bis(3,4-dicyanophenoxy)biphenyland12-mL N-methyl-2-pyrrolidone were added to a 100-mLthree neck round bottle flask equipped with a mechanicalstirrer and refluxing condenser, the mixture was heated at180 °C for few minutes to dissolve sufficiently, then thesolution was cooled to room temperature, and 0.4-g nano-ironparticleswereaddedtothe bottlewithvigorousstirring.The mixture was refluxed at 200 °C for 4 h. Finally, a darkgreenoligomersolutionwasobtained.Thenthesolutionwaspoured to water with vigorous mechanical stirring, theexcess iron was removed with a Millipore filter. Theoligomerwas curedintheovenbythe procedureas follows:250 °C, 4 h; 280 °C, 4 h; 300 °C, 50 h. So the completelycured FePc polymer with considerable magnetic propertieswas obtained.7The preparation of solid nanoiron inside CNTs fromFePc polymer was carried by heating under N2atmosphereat 5 °C?min?1to 300 °C (isotherm for 1 h); 5 °C?min?1toa)Address all correspondence to this author.e-mail: liuxb@uestc.edu.cnDOI: 10.1557/jmr.2011.277J. Mater. Res., Vol. 26, No. 18, Sep 28, 2011? Materials Research Society 20112369