Improvement of the thermal conductivity of a phase change material by the functionalized carbon nanotubes

Abstract Multiwalled carbon nanotubes (MWNTs) were functionalized by oxidation and adsorption of pyrogallol and used to prepare the palmitic acid (PA)/MWNT composite. Spectra of XPS and FTIR were used to characterize the functionalized MWNTs. UV–vis spectra showed the dispersibility of MWNTs in the PA/ethanol solution. Thermal conductivity and DSC measurements showed an enhancement of the thermal conductivity of PA and an improved heat transfer of PA, respectively, by the functionalized MWNTs. This work reveals the relationship between the distribution of MWNT in the PA matrix and the thermal conductivity of the composite. The MWNTs with more oxygen-containing groups can have more hydrogen bonding interactions with the PA molecules, and the nanotubes are better dispersed in the PA/ethanol solution. As a result, MWNTs can be well-dispersed in the PA matrix, and the thermal conductivity of the composite is significantly enhanced.

[1]  A. Sari.  Thermal reliability test of some fatty acids as PCMs used for solar thermal latent heat storage applications , 2003 .

[2]  Mansoo Choi,et al.  Nanofluids containing multiwalled carbon nanotubes and their enhanced thermal conductivities , 2003 .

[3]  Andreas Wiegmann,et al.  Estimating effective thermal conductivity in carbon paper diffusion media , 2010 .

[4]  A. Shard,et al.  ARXPS characterisation of plasma polymerised surface chemical gradients , 2006 .

[5]  Khamid Mahkamov,et al.  Solar energy storage using phase change materials , 2007 .

[6]  Said Al-Hallaj,et al.  Design and simulation of a lithium-ion battery with a phase change material thermal management system for an electric scooter , 2004 .

[7]  Luisa F. Cabeza,et al.  Review on thermal energy storage with phase change: materials, heat transfer analysis and applications , 2003 .

[8]  Wei Feng,et al.  Dispersion of Carbon Nanotubes in Organic Solvents Initiated by Hydrogen Bonding Interactions , 2012 .

[9]  J. Fukai,et al.  Effect of carbon-fiber brushes on conductive heat transfer in phase change materials , 2002 .

[10]  Ibrahim Dincer,et al.  Exergy as a Driver for Achieving Sustainability , 2004 .

[11]  P. Keblinski,et al.  Effect of chemical functionalization on thermal transport of carbon nanotube composites , 2004 .

[12]  Huaqing Xie,et al.  Increasing the thermal conductivity of palmitic acid by the addition of carbon nanotubes , 2010 .

[13]  Huaqing Xie,et al.  Enhancing thermal conductivity of palmitic acid based phase change materials with carbon nanotubes as fillers , 2010 .

[14]  Qun-fang Lei,et al.  A new correlation for thermal conductivity of liquids , 1997 .

[15]  E. Grulke,et al.  Anomalous thermal conductivity enhancement in nanotube suspensions , 2001 .

[16]  A. Sari,et al.  Preparation, thermal properties and thermal reliability of palmitic acid/expanded graphite composite as form-stable PCM for thermal energy storage , 2009 .

[17]  Faruk Civan,et al.  A correlation for thermal conductivity of liquid n-alkanes based on the Vogel–Tammann–Fulcher–Hesse equation , 2008 .

[18]  A. Sari,et al.  Fatty acid/poly(methyl methacrylate) (PMMA) blends as form-stable phase change materials for latent heat thermal energy storage , 2008 .

[19]  F. Billes,et al.  Vibrational spectroscopic calculations on pyrogallol and gallic acid , 2002 .

[20]  Huaqing Xie,et al.  Preparation and Thermal Properties of Grafted CNTs Composites , 2011 .

[21]  D. A. Shirley,et al.  High-Resolution X-Ray Photoemission Spectrum of the Valence Bands of Gold , 1972 .

[22]  Huaqing Xie,et al.  Thermal properties of heat storage composites containing multiwalled carbon nanotubes , 2008 .

[23]  Eklund,et al.  Solution properties of single-walled carbon nanotubes , 1998, Science.

[24]  R. Smalley,et al.  Infrared Spectral Evidence for the Etching of Carbon Nanotubes: Ozone Oxidation at 298 K , 2000 .

[25]  T. Chuah,et al.  Fatty Acids as Phase Change Materials (PCMs) for Thermal Energy Storage: A Review , 2005 .

[26]  A. Sayigh,et al.  Some fatty acids as phase-change thermal energy storage materials , 1994 .

[27]  Huaqing Xie,et al.  Measuring the thermal conductivity of a single carbon nanotube. , 2005, Physical review letters.

[28]  K. Ng,et al.  Reducing thermal contact resistance using a bilayer aligned CNT thermal interface material , 2010 .

[29]  W. Goddard,et al.  Thermal conductivity of carbon nanotubes , 2000 .

[30]  M. Radosavljevic,et al.  Carbon nanotube composites for thermal management , 2002, cond-mat/0205418.

[31]  J. Selman,et al.  Thermal conductivity enhancement of phase change materials using a graphite matrix , 2006 .

[32]  D. Lin,et al.  Adsorption of phenolic compounds by carbon nanotubes: role of aromaticity and substitution of hydroxyl groups. , 2008, Environmental science & technology.

[33]  T. Gates,et al.  Modeling of interfacial modification effects on thermal conductivity of carbon nanotube composites , 2006 .

[34]  S. Schroeder,et al.  Quantitative analysis of saccharides by X‐ray photoelectron spectroscopy , 2009 .

[35]  Liwu Fan,et al.  Thermal conductivity enhancement of phase change materials for thermal energy storage: A review , 2011 .

[36]  Kwon,et al.  Unusually high thermal conductivity of carbon nanotubes , 2000, Physical review letters.

[37]  Yajuan Zhong,et al.  Heat transfer enhancement of paraffin wax using compressed expanded natural graphite for thermal energy storage , 2010 .