Fe3O4–Au and Fe2O3–Au Hybrid Nanorods: Layer-by-Layer Assembly Synthesis and Their Magnetic and Optical Properties
© The Author(s) 2010
Received: 26 May 2010
Accepted: 15 July 2010
Published: 1 August 2010
A layer-by-layer technique has been developed to synthesize FeOOH–Au hybrid nanorods that can be transformed into Fe2O3–Au and Fe3O4–Au hybrid nanorods via controllable annealing process. The homogenous deposition of Au nanoparticles onto the surface of FeOOH nanorods can be attributed to the strong electrostatic attraction between metal ions and polyelectrolyte-modified FeOOH nanorods. The annealing atmosphere controls the phase transformation from FeOOH–Au to Fe3O4–Au and α-Fe2O3–Au. Moreover, the magnetic and optical properties of as-synthesized Fe2O3–Au and Fe3O4–Au hybrid nanorods have been investigated.
KeywordsLayer-by-layer Hybrid nanomaterials Iron oxide Magnetic properties
Hybrid nanomaterials consisting of two or more different nanoscale functionalities have attracted much attention due to their novel combined properties and technological applications [1, 2]. Among them, iron oxide–Au (Fe3O4–Au, α/γ-Fe2O3–Au) nanocomposites are of great importance for their combined optical and magnetic properties and potential applications in the fields of biotechnologies and catalysts [3–8]. Up to now, many methods have been developed to synthesize various Fe3O4–Au and α/γ-Fe2O3–Au nanocomposites [9–19]. For example, Yu et al.  reported the synthesis of dumbbell-like Fe3O4–Au nanoparticles using decomposition of Fe(CO)5 on the surface of the Au nanoparticles followed by oxidation in 1-octadecene. Fe3O4–Au core–shell nanoparticles could be prepared with room-temperature coating of Au on the surface of Fe3O4 nanoparticles by reducing HAuCl4 in a chloroform solution of oleylamine . Wu et al.  prepared magnetic Fe3O4–Au nanoparticles by the controlling a combination of chemically tunable chelating layer modifications for magnetic core and further deposition of Au on the amine-functionalized Fe3O4 surface. Bao et al.  reported the synthesis of γ-Fe2O3–Au nanoparticles with different Au shell thickness by reducing HAuCl4 on the surface of γ-Fe2O3 nanoparticles. Moreover, the synthesis and transformation of 1D nanostructures and their hybrids are of particular interest due to their immense applications [20–22]. However, to the best of our knowledge, there is no report for the controllable synthesis of Fe2O3–Au and Fe3O4–Au hybrid 1D nanostructures.
Layer-by-layer technique is based on the electrostatic attraction between charge species, and it has been widely used to synthesize nanocomposites [23–28]. More recently, this technique has been realized to prepare hybrid 1D nanostructures [29–36]. Herein, we use layer-by-layer technique to synthesize uniform FeOOH–Au hybrid nanorods that can be controllably transformed into Fe2O3–Au and Fe3O4–Au hybrid nanorods. The magnetic and optical properties of as-synthesized Fe2O3–Au and Fe3O4–Au hybrid nanorods have been investigated.
Poly (sodium 4-styrenesulfonate) (PSS) and Poly (allylamine hydrochloride) (PAH) were purchased from Alfa Aesar Co. Ltd. All the chemicals were of analytical grade without further purification. First, FeOOH nanorods were prepared by a hydrothermal route described elsewhere . Second, the pristine FeOOH nanorods were modified by polyelectrolyte (PAH/PSS/PAH) in sequence via layer-by-layer assembly. Briefly, 10 mg FeOOH nanorods was sonicated for 1 h in 50 ml 1 M NaCl solution, and 80 mg PAH was added and stirred for 0.5 h. Subsequently, the excess PAH was removed by six repeated centrifugation/wash cycles. Similarly, the PSS and PAH layers were then coated on the surface of the PAH-modified FeOOH nanorods to obtain the PAH/PSS/PAH-modified FeOOH nanorods. Third, FeOOH–Au nanorods were fabricated by chemical reaction using HAuCl4, trisodium citrate, and NaBH4 as reactants on PAH/PSS/PAH modified FeOOH nanorod templates. The resulting solid products were centrifuged, washed with distilled water and ethanol to remove the ions possibly remaining in the final products, and finally dried at 80°C in air.
For the synthesis of α-Fe2O3–Au nanorods, the as-prepared FeOOH–Au nanorods were heated to 500°C for 3 h in air. While for the synthesis of Fe3O4–Au nanorods, the as-prepared FeOOH–Au nanorods were heated to 400°C for 3 h under H2/Ar (10% H2) atmosphere.
The obtained samples were characterized by X-ray powder diffraction (XRD) using a Rigaku D/max-ga X-ray diffractometer with graphite monochromatized Cu Kα radiation (γ = 1.54178 Å). The morphology and structure of the samples were examined by transmission electron microscopy (TEM, JEM-200 CX, 160 kV), field emission scanning electron microscopy (FESEM, Hitachi S-4800) and high-resolution transmission electron microscopy (HRTEM, JEOL JEM-2010). The infrared (IR) spectra were measured with a Nicolet Nexus FTIR 670 spectrophotometer. Magnetization measurements were carried out using a physical property measurement system (PPMS-9, Quantum Design). The optical absorption of the products was examined by a Perkin–Elmer Lambda 20 UV/vis Spectrometer. BET surface area and pore volume were tested using Beckman coulter omnisorp 100cx.
Results and Discussion
FeOOH–Au hybrid nanorods have been synthesized via layer-by-layer assembly, which can be transformed into α-Fe2O3–Au and Fe3O4–Au hybrid nanorods by controllable annealing process. The strong electrostatic attraction between AuCl4− and polyelectrolyte-modified FeOOH nanorods plays the most important role in the uniform deposition of Au nanoparticles. The annealing atmosphere determines the phase transformation from FeOOH–Au to α-Fe2O3–Au and Fe3O4–Au. The as-synthesized Fe3O4–Au hybrid nanorods show the high saturation magnetizations, and α-Fe2O3–Au hybrid nanorods show the low saturation magnetizations, respectively. The UV–vis analysis indicates that both Fe3O4–Au and α-Fe2O3–Au hybrid nanorods show a broad peak located at about 525 nm. It is believed that the as-synthesized Fe3O4–Au and α-Fe2O3–Au hybrid nanorods can be applied in biotechnologies and catalysts, respectively.
The authors thank the Doctoral Science Foundation of Zhejiang Sci-Tech University (no. 0803611-Y) and National Natural Science Foundation of China (no. 50976106) for financial support.
This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.
- Mieszawska AJ, Jalilian R, Sumanasekera GU, Zamborini FP: Small. 2007, 3: 722. COI number [1:CAS:528:DC%2BD2sXls1Wqtb8%3D] 10.1002/smll.200600727View ArticleGoogle Scholar
- Sanchez C, Julian B, Belleville P, Popall M: J. Mater. Chem.. 2005, 15: 3559. COI number [1:CAS:528:DC%2BD2MXpsFeitrY%3D] 10.1039/b509097kView ArticleGoogle Scholar
- Bao J, Chen W, Liu TT, Zhu YL, Jin PY, Wang LY, Liu JF, Wei YG, Li YD: ACS Nano. 2007, 1: 293. COI number [1:CAS:528:DC%2BD2sXht1CmtrbN] 10.1021/nn700189hView ArticleGoogle Scholar
- Zhao XL, Cai YQ, Wang T, Shi YL, Jiang GB: Anal. Chem.. 2008, 80: 9091. COI number [1:CAS:528:DC%2BD1cXhtlWqtbrL] 10.1021/ac801581mView ArticleGoogle Scholar
- Xu CJ, Wang BD, Sun SH: J. Am. Chem. Soc.. 2009, 131: 4216. COI number [1:CAS:528:DC%2BD1MXjtFKgs78%3D] 10.1021/ja900790vView ArticleGoogle Scholar
- Xie HY, Zhen R, Wang B, Feng Y, Chen P, Hao J: J. Phy. Chem. C. 2010, 114: 4825. COI number [1:CAS:528:DC%2BC3cXisFGmtro%3D] 10.1021/jp910753fView ArticleGoogle Scholar
- Andreeva D, Idakiev V, Tabakova T, Andreev A: J. Catal.. 1996, 158: 354. COI number [1:CAS:528:DyaK28XmsVGhsA%3D%3D] 10.1006/jcat.1996.0035View ArticleGoogle Scholar
- Lee YM, Garcia MA, Huls NAF, Sun SH: Angew. Chem. Int. Ed.. 2010, 149: 1271. 10.1002/anie.200906130View ArticleGoogle Scholar
- Wang LY, Luo J, Fan Q, Suzuki M, Suzuki TS, Engelhard MH, Lin YH, Kim N, Wang JQ, Zhong CJ: J. Phys. Chem. B. 2005, 109: 21593. COI number [1:CAS:528:DC%2BD2MXhtFCmtb%2FL] 10.1021/jp0543429View ArticleGoogle Scholar
- Yu H, Chen M, Rice PM, Wang SX, White RL, Sun SH: Nano Lett.. 2005, 5: 379. COI number [1:CAS:528:DC%2BD2MXkvFWisA%3D%3D]; Bibcode number [2005NanoL...5..379Y] 10.1021/nl047955qView ArticleGoogle Scholar
- Xu ZC, Hou YL, Sun SH: J. Am. Chem. Soc.. 2007, 129: 8698. COI number [1:CAS:528:DC%2BD2sXmslyqsrc%3D] 10.1021/ja073057vView ArticleGoogle Scholar
- Wu W, He QG, Chen H, Tang JX, Nie LB: Nanotechnology. 2007, 18: 145609. Bibcode number [2007Nanot..18n5609W] 10.1088/0957-4484/18/14/145609View ArticleGoogle Scholar
- Liu XW, Hu QY, Zhang XJ, Fang Z, Wang Q: J. Phys. Chem. C. 2008, 112: 12728. COI number [1:CAS:528:DC%2BD1cXovVOhtr8%3D] 10.1021/jp8035617View ArticleGoogle Scholar
- Guo SJ, Dong SJ, Wang EK: Chem. Eur. J.. 2009, 15: 2416. COI number [1:CAS:528:DC%2BD1MXjtFSnsrk%3D] 10.1002/chem.200801942View ArticleGoogle Scholar
- Chin SF, Iyer KS, Raston CL: Cryst. Growth Des.. 2009, 9: 2685. COI number [1:CAS:528:DC%2BD1MXktlygsrw%3D] 10.1021/cg8013199View ArticleGoogle Scholar
- Goon IY, Lai LMH, Lim M, Munroe P, Gooding JJ, Amal R: Chem. Mater.. 2009, 21: 673. COI number [1:CAS:528:DC%2BD1MXpt1ejtg%3D%3D] 10.1021/cm8025329View ArticleGoogle Scholar
- Lim JK, Majetich SA, Tilton RD: Langmuir. 2009, 25: 13384. COI number [1:CAS:528:DC%2BD1MXptlSntbk%3D] 10.1021/la9019734View ArticleGoogle Scholar
- Bao F, Yao J, Gu R: Langmuir. 2009, 25: 10782. COI number [1:CAS:528:DC%2BD1MXns1Siurk%3D] 10.1021/la901337rView ArticleGoogle Scholar
- Wang Y, Shen YH, Xie AJ, Li SK, Wang XF, Cai Y: J. Phys. Chem. C. 2010, 114: 4297. COI number [1:CAS:528:DC%2BC3cXitFehtrg%3D] 10.1021/jp9099804View ArticleGoogle Scholar
- Yan CL, Xue DF: J. Phys. Chem. B. 2006, 110: 25850. COI number [1:CAS:528:DC%2BD28Xht1Clu7bF] 10.1021/jp0659296View ArticleGoogle Scholar
- Yan CL, Xue DF: Phys. Scr.. 2007, T129: 288. COI number [1:CAS:528:DC%2BD1cXjs1KqtQ%3D%3D]; Bibcode number [2007PhST..129..288Y] 10.1088/0031-8949/2007/T129/064View ArticleGoogle Scholar
- Zhao X, Ren X, Sun CT, Zhang X, Sun YF, Si YF, Yan CL, Xu JS, Xue DF: Funct. Mater. Lett.. 2008, 1: 167. COI number [1:CAS:528:DC%2BD1MXjtFCqtrc%3D] 10.1142/S1793604708000393View ArticleGoogle Scholar
- Decher G: Science. 1997, 277: 1232. COI number [1:CAS:528:DyaK2sXlslaitL4%3D] 10.1126/science.277.5330.1232View ArticleGoogle Scholar
- Correa-Duarte MA, Kosiorek A, Kandulski W, Giersig M, Liz-Marzan LM: Chem. Mater.. 2005, 17: 3268. COI number [1:CAS:528:DC%2BD2MXktFCgsb8%3D] 10.1021/cm047710eView ArticleGoogle Scholar
- Caruso F, Caruso RA, Mohwald H: Science. 1998, 282: 1111. COI number [1:CAS:528:DyaK1cXntlaqs74%3D]; Bibcode number [1998Sci...282.1111C] 10.1126/science.282.5391.1111View ArticleGoogle Scholar
- Caruso F: Adv. Mater.. 2001, 13: 11. COI number [1:CAS:528:DC%2BD3MXhtVyktLg%3D] 10.1002/1521-4095(200101)13:1<11::AID-ADMA11>3.0.CO;2-NView ArticleGoogle Scholar
- Ai SF, He Q, Tao C, Zheng SP, Li JB: Macromol. Rapid. Commun.. 2005, 26: 1965. COI number [1:CAS:528:DC%2BD28Xkt12ksg%3D%3D] 10.1002/marc.200500590View ArticleGoogle Scholar
- Ai SF, Lu G, He Q, Li JB: J. Am. Chem. Soc.. 2003, 125: 11140. COI number [1:CAS:528:DC%2BD3sXmsVynsrc%3D] 10.1021/ja0356378View ArticleGoogle Scholar
- Du N, Zhang H, Chen BD, Ma XY, Liu ZH, Wu JB, Yang DR: Adv. Mater.. 2007, 19: 1641. COI number [1:CAS:528:DC%2BD2sXnsVagsbg%3D] 10.1002/adma.200602128View ArticleGoogle Scholar
- Du N, Zhang H, Ma XY, Yang DR: Chem. Commun.. 2008, 6182.Google Scholar
- Du N, Zhang H, Yu JX, Wu P, Zhai CX, Xu YF, Wang JZ, Yang DR: Chem. Mater.. 2009, 21: 5264. COI number [1:CAS:528:DC%2BD1MXht1OjtrfL] 10.1021/cm902322eView ArticleGoogle Scholar
- Du N, Zhang H, Wu P, Yu JX, Yang DR: J. Phys. Chem. C. 2009, 113: 17387. COI number [1:CAS:528:DC%2BD1MXhtFWqtL7L] 10.1021/jp906349cView ArticleGoogle Scholar
- Wu P, Zhang H, Du N, Ruan LY, Yang DR: J. Phys. Chem. C. 2009, 113: 8147. COI number [1:CAS:528:DC%2BD1MXkslCqtrc%3D] 10.1021/jp901896uView ArticleGoogle Scholar
- Huang SJ, Artyukhin AB, Wang YM, Ju JW, Stroeve P, Noy A: J. Am. Chem. Soc.. 2005, 127: 14176. COI number [1:CAS:528:DC%2BD2MXhtVWnurbP] 10.1021/ja053060jView ArticleGoogle Scholar
- Tian Y, He Q, Tao C, Li JB: Langmuir. 2006, 22: 360. COI number [1:CAS:528:DC%2BD2MXhtF2ht73N] 10.1021/la0524768View ArticleGoogle Scholar
- Gong KP, Yu P, Su L, Xiong SX, Mao LQ: J. Phys. Chem. C. 2007, 111: 1882. COI number [1:CAS:528:DC%2BD2sXltlehug%3D%3D] 10.1021/jp0628636View ArticleGoogle Scholar
- Chen YJ, Zhu CL, Shi XL, Cao MS, Jin HB: Nanotechnology. 2008, 19: 205603. Bibcode number [2008Nanot..19t5603C] 10.1088/0957-4484/19/20/205603View ArticleGoogle Scholar
- Grumelli D, Bonazzola C, Calvo EJ: Electrochem. Commun.. 2006, 8: 1353. COI number [1:CAS:528:DC%2BD28XotVCqur8%3D] 10.1016/j.elecom.2006.06.015View ArticleGoogle Scholar
- Mishra YK, Mohapatra S, Singhal R, Avasthi DK, Agarwal DC, Ogale SB: Appl. Phys. Lett.. 2008, 92: 043107. Bibcode number [2008ApPhL..92d3107M] 10.1063/1.2838302View ArticleGoogle Scholar
- Krehula S, Music S: J. Alloy Compd.. 2006, 416: 284. COI number [1:CAS:528:DC%2BD28XkvF2gsLs%3D] 10.1016/j.jallcom.2005.09.016View ArticleGoogle Scholar
- Daou TJ, Greneche JM, Pourroy G, Buathong S, Derory A, Ulhaq-Bouillet C, Donnio B, Guillon D, Begin-Colin S: Chem. Mater.. 2008, 20: 5869. COI number [1:CAS:528:DC%2BD1cXhtVWmu7%2FP] 10.1021/cm801405nView ArticleGoogle Scholar
- Han DH, Wang JP, Luo HL: J. Magn. Magn. Mater.. 1994, 136: 176. COI number [1:CAS:528:DyaK2MXnvFyjuw%3D%3D]; Bibcode number [1994JMMM..136..176H] 10.1016/0304-8853(94)90462-6View ArticleGoogle Scholar
- Yin S, Sato T: J. Photochem. Photobiol. A. 2005, 169: 89. COI number [1:CAS:528:DC%2BD2cXps1Oqt74%3D] 10.1016/j.jphotochem.2004.05.038View ArticleGoogle Scholar
- Daniel MC, Astruc D: Chem. Rev.. 2004, 104: 293. COI number [1:CAS:528:DC%2BD3sXpvFGlur0%3D] 10.1021/cr030698+View ArticleGoogle Scholar