Polymer-composite with high dielectric constant and enhanced absorption properties based on graphene–CuS nanocomposites and polyvinylidene fluoride

Novel reduced graphene oxide (RGO)/CuS nanocomposites, featuring CuS microspheres embedded in reduced graphene oxide (RGO) layers, are successfully fabricated by using an in situ growth approach in the presence of cexadecyl trimethyl ammonium bromide (CTAB) under mild wet-chemical conditions (140 °C). Characterization of the nanocomposites indicates that the CuS complex microspheres with relatively uniform size are embedded in the RGO layers to form unique core–shell nanostructures. A simple hot-press process is employed to synthesize the RGO/CuS/PVDF composites. With a filler loading of 15 wt%, the dielectric constant of the composites can reach 36 at 2 GHz, which is 10 times higher than that of pure PVDF. The composites with a filler loading of 5 wt% exhibit high values of reflection loss and the maximum loss is 32.7 dB at 10.7 GHz when the thickness is just 2.5 mm, and it can be adjusted by the thickness. The enhanced mechanism is also explained based on the Debye dipolar relaxation of the composites. The composite with a high dielectric constant is a promising material in high capacitance, while the composite with enhanced absorption can decrease the environmental pollution caused by microwave irradiation.

[1]  Liuwan Zhang,et al.  Anomalous thermal hysteresis in dielectric permittivity of CaCu3Ti4O12 , 2008 .

[2]  Li Li Zhang,et al.  Layered graphene oxide nanostructures with sandwiched conducting polymers as supercapacitor electrodes. , 2010, Langmuir : the ACS journal of surfaces and colloids.

[3]  D. Das-gupta,et al.  Pyroelectricity in polymers , 1991 .

[4]  B. Wen,et al.  Enhanced wave absorption of nanocomposites based on the synthesized complex symmetrical CuS nanostructure and poly(vinylidene fluoride) , 2013 .

[5]  Manoj Kumar Patra,et al.  Microwave absorbing properties of a thermally reduced graphene oxide/nitrile butadiene rubber composite , 2012 .

[6]  Xinyu Xue,et al.  Graphene/polyaniline nanorod arrays: synthesis and excellent electromagnetic absorption properties , 2012 .

[7]  Jiayan Luo,et al.  Effect of sheet morphology on the scalability of graphene-based ultracapacitors. , 2013, ACS nano.

[8]  Xiaoyun Qin,et al.  Biomolecule-assisted, environmentally friendly, one-pot synthesis of CuS/reduced graphene oxide nanocomposites with enhanced photocatalytic performance. , 2012, Langmuir : the ACS journal of surfaces and colloids.

[9]  Lidong Li,et al.  An environment-friendly preparation of reduced graphene oxide nanosheets via amino acid , 2011, Nanotechnology.

[10]  Yi Yin,et al.  Giant Dielectric Permittivities in Functionalized Carbon-Nanotube/ Electroactive-Polymer Nanocomposites† , 2007 .

[11]  Zhong-Zhen Yu,et al.  Tough graphene-polymer microcellular foams for electromagnetic interference shielding. , 2011, ACS applied materials & interfaces.

[12]  J. Cavaillé,et al.  Dielectric and piezoelectric properties of copolymer-ferroelectric composite , 1990 .

[13]  K. Novoselov,et al.  Detection of individual gas molecules adsorbed on graphene. , 2006, Nature materials.

[14]  Z. Dang,et al.  Carbon nanotube composites with high dielectric constant at low percolation threshold , 2005 .

[15]  C. Au,et al.  Large-scale synthesis, characterization and microwave absorption properties of carbon nanotubes of different helicities , 2009 .

[16]  SUPARNA DUTTASINHA,et al.  Graphene: Status and Prospects , 2009, Science.

[17]  M. Panda,et al.  On the question of percolation threshold in polyvinylidene fluoride/nanocrystalline nickel composites , 2008 .

[18]  Hua Zhang,et al.  Graphene-based composites. , 2012, Chemical Society reviews.

[19]  Ping Xu,et al.  The electromagnetic property of chemically reduced graphene oxide and its application as microwave absorbing material , 2011 .

[20]  J. Deng,et al.  Preparation and photocatalytic performance of Ag/ZnO nano-composites , 2007 .

[21]  H. Meng,et al.  Microwave-absorption properties of ZnO-coated iron nanocapsules , 2008 .

[22]  Qing Chen,et al.  Microwave Absorption Enhancement and Complex Permittivity and Permeability of Fe Encapsulated within Carbon Nanotubes , 2004 .

[23]  S. Stankovich,et al.  Synthesis of graphene-based nanosheets via chemical reduction of exfoliated graphite oxide , 2007 .

[24]  Lin Guo,et al.  Fabrication of radial ZnO nanowire clusters and radial ZnO/PVDF composites with enhanced dielectric properties , 2008 .

[25]  Minghui Li,et al.  Evaluation of the microwave absorption property of flake graphite , 2009 .

[26]  Donghang Yan,et al.  Multistep synthesis, growth mechanism, optical, and microwave absorption properties of ZnO dendritic nanostructures , 2008 .

[27]  Cheng Huang,et al.  Microstructure and Electromechanical Properties of Carbon Nanotube/ Poly(vinylidene fluoride—trifluoroethylene—chlorofluoroethylene) Composites , 2005 .

[28]  Paul S. Wheatley,et al.  Ionic liquids and eutectic mixtures as solvent and template in synthesis of zeolite analogues , 2004, Nature.

[29]  R. Kaner,et al.  Honeycomb carbon: a review of graphene. , 2010, Chemical reviews.

[30]  Ce-Wen Nan,et al.  Novel Ferroelectric Polymer Composites with High Dielectric Constants , 2003 .

[31]  M. Cao,et al.  Microwave absorption properties and mechanism of cagelike ZnO∕SiO2 nanocomposites , 2007 .

[32]  Fan Zhang,et al.  Synthesis, Multi-Nonlinear Dielectric Resonance, and Excellent Electromagnetic Absorption Characteristics of Fe3O4/ZnO Core/Shell Nanorods , 2010 .

[33]  Wenjian Weng,et al.  Percolative conductor/polymer composite films with significant dielectric properties , 2007 .

[34]  Shaoli Guo,et al.  Microwave absorption properties of CeO2 and Zn-modified CeO2 microstructures , 2012 .

[35]  Xiaoping Shen,et al.  Graphene–inorganic nanocomposites , 2012 .

[36]  Hua Zhang,et al.  Preparation of novel 3D graphene networks for supercapacitor applications. , 2011, Small.

[37]  Tao Wang,et al.  Direct Incorporation of Magnetic Constituents within Ordered Mesoporous Carbon−Silica Nanocomposites for Highly Efficient Electromagnetic Wave Absorbers , 2010 .

[38]  B. Wen,et al.  Controllable Fabrication of CuS Hierarchical Nanostructures and Their Optical, Photocatalytic, and Wave Absorption Properties , 2013 .

[39]  Liangbing Hu,et al.  Emerging Transparent Electrodes Based on Thin Films of Carbon Nanotubes, Graphene, and Metallic Nanostructures , 2011, Advanced materials.

[40]  Young-Seak Lee,et al.  Fluorination effects of carbon black additives for electrical properties and EMI shielding efficiency by improved dispersion and adhesion , 2009 .

[41]  Kwang S. Kim,et al.  Large-scale pattern growth of graphene films for stretchable transparent electrodes , 2009, Nature.

[42]  Yong Zhang,et al.  Green Approach To Prepare Graphene-Based Composites with High Microwave Absorption Capacity , 2011 .

[43]  R. Ruoff,et al.  Thermal transport in suspended and supported monolayer graphene grown by chemical vapor deposition. , 2010, Nano letters.

[44]  Hua Bai,et al.  Functional Composite Materials Based on Chemically Converted Graphene , 2011, Advanced materials.

[45]  J. Dunn,et al.  Thermal oxidation of covellite (CuS) , 2001 .

[46]  G. Graff,et al.  Ternary self-assembly of ordered metal oxide-graphene nanocomposites for electrochemical energy storage. , 2010, ACS nano.

[47]  C. Choy,et al.  Study on BaTiO3/P(VDF-TrFE) 0–3 composites , 1999 .

[48]  Shengtao Li,et al.  Microstructure and dielectric characterization of micro- nanosize co-filled composite films with high dielectric permittivity , 2011, IEEE Transactions on Dielectrics and Electrical Insulation.

[49]  Yunqi Liu,et al.  Controllable Synthesis of Graphene and Its Applications , 2010, Advanced materials.

[50]  Roberto Car,et al.  Functionalized single graphene sheets derived from splitting graphite oxide. , 2006, The journal of physical chemistry. B.

[51]  Yan Wang,et al.  Electromagnetic interference shielding of graphene/epoxy composites , 2009 .

[52]  Jie Yuan,et al.  Improved dielectric properties and highly efficient and broadened bandwidth electromagnetic attenuation of thickness-decreased carbon nanosheet/wax composites , 2013 .

[53]  Shuhong Yu,et al.  Tunable wave absorption properties of β-MnO2 nanorods and their application in dielectric composites , 2012 .