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Synthesis and characterization of Ag and Al doped ZnO dispersed nanofluids for heat transfer applications
Materials Today: Proceedings xxx (xxxx) xxx
Contents lists available at ScienceDirect
Materials Today: Proceedings journal homepage: www.elsevier.com/locate/matpr
Synthesis and characterization of Ag and Al doped ZnO dispersed nanofluids for heat transfer applications Aravinth Raj Arivalagan a,⇑, V. Karthik b, R. Ramji b, P.G. Venkatakrishnan c a
Materials Engineering and Nanotechnology, Politecnico Di Milano, Piazza Leonardo da Vinci, 32, 20133 Milano, MI, Italy Department of Metallurgical and Materials Engineering, National Institute of Technology, Tiruchirappalli 620015, Tamil Nadu, India c Department of Mechanical Engineering, Mahendra Engineering College, Mallasamudram, Namakkal 637503, Tamil Nadu, India b
a r t i c l e
i n f o
Article history: Received 16 August 2019 Accepted 17 September 2019 Available online xxxx Keywords: Nanofluids Transient hot wire technique ZnO nanoparticles Al and Ag doping Ethylene glycol + water
a b s t r a c t In this work, Ag and Al co-doped ZnO nanoparticles have been prepared through chemical synthesis route using zinc acetate, silver nitrate and aluminium nitrate. The synthesized nanoparticles are characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The nanofluids are prepared by dispersing 1 wt% of Al and Ag doped ZnO nanoparticles in ethylene glycol (EG)-water (W) mixture. The effect of base fluid on the thermal conductivity enhancement of the nanofluids has been studied by employing three different EG + Water mixtures namely, 25% EG-75% Water, 50% EG-50% Water and 75% EG-25% Water as base fluids. The nanoparticles are homogeneously dispersed in base fluids by using combined magnetic stirring and ultrasonication. The thermal conductivity of the nanofluids are measured through transient hot-wire technique. It is observed that the addition of small amount of Al and Ag doped ZnO nanoparticles to the ethylene glycol-water mixture increases the thermal conductivity of the base fluid. The 50% EG-50 Water mixture showed highest thermal conductivity enhancement of 37% compared to other base fluids when 1% Al and Ag doped ZnO nanoparticles are dispersed. Ó 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International conference on Materials and Manufacturing Methods.
1. Introduction The research and development on nanotechnology have been growing steadily in the fields of science and technology in the recent decades. The enhancement of the thermal properties in the areas of industrial cooling, microelectronics and energy storage is made possible with the invention of nanofluids which are nanoparticles dispersed in fluids such as water, ethylene glycol, etc [1,2]. Different mechanisms like Brownian motion of nanoparticles, formation of an interface layer around the nanoparticle and particle clustering are responsible for the enhancement in the thermal properties of the nanofluids when compared to their base fluids [3,4]. The thermal conductivity of the nanoparticles plays an important role in thermal conductivity enhancement of the nanofluids. The metallic particles dispersed nanofluids will have better thermal properties on comparison to the nonmetallic particles dispersed nanofluids. It is known fact that the transport prop⇑ Corresponding author. E-mail address: [email protected] (A.R. Arivalagan).
erties of the semiconductor particles may be improved by the doping process [5]. The present work focus on the Ag and Al codoped ZnO semiconductor nanoparticle dispersed nanofluids for heat transfer applications. The laboratory synthesis of ZnO nanoparticles using sol-gel method and their characterization is shown by Hasnidawani et al. [6]. The importance of magnetic and ultrasonic stirring for the monodispersing of the nanoparticles in the fluids is shown by Chung et al. [7]. The ZnO nanofluids with base fluid as water and ethylene glycol is studied by Chung et al. and Yu et al. [7,8]. Suganthi et al. [9] have reported a 33.4% enhancement in the thermal conductivity for ZnO nanofluids. Xie et al. [10] have discussed the effect of nanoparticle loading, base fluid temperature, type of nanoparticle and base fluid, particle size, etc. on the thermal conductivity enhancement of the nanofluids. The effect of base fluid proportion on the thermal conductivity of nanofluids is studied in the present work. In this work aluminium and silver doped zinc oxide nanoparticles were synthesized using simple wet chemical synthesis method, then the nanoparticles were dispersed in a mixture of water and ethylene glycol using magnetic and ultrasonic stirring to produce nanofluids.
https://doi.org/10.1016/j.matpr.2019.09.130 2214-7853/Ó 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International conference on Materials and Manufacturing Methods.
Please cite this article as: A. R. Arivalagan, V. Karthik, R. Ramji et al., Synthesis and characterization of Ag and Al doped ZnO dispersed nanofluids for heat transfer applications, Materials Today: Proceedings, https://doi.org/10.1016/j.matpr.2019.09.130
2
A.R. Arivalagan et al. / Materials Today: Proceedings xxx (xxxx) xxx
Table 1 Three types of nanofluids and their constituents.
2. Materials and methods
Content
Sample A
Sample B
Sample C
Ethylene glycol Distilled water Nanoparticles conc.
50% 50% 1%
75% 25% 1%
25% 75% 1%
2.1. Synthesis of Ag and Al co-doped ZnO nanoparticles The procured zinc acetate, silver nitrate, aluminium nitrate, ammonia and ethylene glycol are directly used without any further pretreatment. In order to synthesize the Ag and Al co-doped ZnO nanoparticles, stock solutions of zinc acetate Zn(CH3COO)22H2O (1 M) was initially prepared. Then 10 ml of silver nitrate solution (0.1 M) is added in 50 ml zinc acetate stock solution under stirring. Then 10 ml of 0.04 M aluminium nitrate solution is added under continuous stirring. To this stock solution 2–3 ml ammonia (0.5 M) solution was added under continuous stirring in order to get the pH value of reactants between 8 and 11. These solutions were transferred into teflon-lined sealed stainless steel autoclaves and maintained at temperature range of 70–75 °C for 2 h under autogenous pressure. It was then allowed to cool naturally to room temperature. After the completion of the reaction, the resulting white solid products were washed with distilled water, filtered and then dried in a laboratory oven at 40 °C. 2.2. Synthesis of nanofluids
Fig. 1. Energy dispersive X-ray spectrum of synthesized Ag and Al co-doped ZnO nanoparticles.
Table 2 Weight% of elements present in the synthesized nanomaterial. Elements
Weight%
Zn O Al Ag
71.66 22.58 3.05 2.71
Ag and Al co-doped ZnO nanoparticles of 1wt% concentration were dispersed in ethylene glycol and water mixture using ultrasonic and magnetic stirring for 60 min. Three types of nanofluids were prepared by varying the volume percentage of ethylene glycol and water mixture in the base fluid as shown in the Table 1. Thermal conductivity of the synthesized nanofluids are measured through transient hot-wire technique using KD2 pro equipment under room temperature and atmospheric pressure. 3. Results and discussion The EDS results of the synthesized nanoparticles are shown in Fig. 1. It clearly shows that the elements present in the synthesized material are zinc, oxygen, silver and aluminium. Table 2 shows the weight percentage of the elements present in the synthesized
Fig. 2. Elemental mapping of synthesized Ag and Al co-doped ZnO nanoparticles.
Please cite this article as: A. R. Arivalagan, V. Karthik, R. Ramji et al., Synthesis and characterization of Ag and Al doped ZnO dispersed nanofluids for heat transfer applications, Materials Today: Proceedings, https://doi.org/10.1016/j.matpr.2019.09.130
A.R. Arivalagan et al. / Materials Today: Proceedings xxx (xxxx) xxx
Fig. 3. SEM image of synthesized Ag and Al co-doped ZnO nanoparticles.
Fig. 4. XRD pattern of synthesized Ag and Al co-doped ZnO nanoparticles.
Table 3 Thermal conductivity of the nanofluid on comparison with its base fluid. Sample
Water %
EG %
Thermal conductivity (W/mK)
Enhancement %
Base fluid A Nanofluid A
25 25
75 75
0.244 0.308
20.78
Base fluid B Nanofluid B
50 50
50 50
0.309 0.493
37.28
Base fluid C Nanofluid C
75 25
25 75
0.388 0.441
12.01
nanomaterial. The EDS results clearly indicates the presence of Ag and Al in the ZnO nanoparticles. The Fig. 2 shows the X-ray elemental mapping of the elements present in the synthesized ZnO nanoparticles. The figures clearly reveal the homogeneous doping of Ag and Al in the ZnO particles. The continuous stirring during the synthesis stage enhanced the uniform distribution of the Ag and Al in ZnO particles. The SEM image of the synthesized ZnO powder sample is presented in Fig. 3. The powder particles are agglomerated, hence combined ultrasonication and magnetic stirring is essential to disintegrate the ZnO nanoparticles during nanofluid preparation. The Fig. 4 shows the XRD pattern of the synthesize ZnO sample. The peaks in the XRD pattern matches well with the zincite (ZnO, JCPDS 5-0664) structure. Akhtar et al. [11] has also obtained similar kind XRD pattern for ZnO nanoparticles. The average crystallite size calculated from the XRD peak using Scherer formula is 28 nm.
3
Fig. 5. Thermal conductivity variation in the different base fluid and their corresponding Nano fluids.
The thermal conductivity of various samples was measured using the transient hot wire technique by KD2 Pro equipment. There is a clear enhancement in the thermal conductivity of the base fluids on addition of synthesized nanoparticles. Table 3 shows the thermal conductivity of the nanofluids and its enhancement percentage in comparison with its base fluids (sample A, B, C). Fig. 5 shows the thermal conductivity of the base fluid and nanofluids. It is evident that a maximum thermal conductivity enhancement of 37.28% is shown by nanofluids prepared with 1 wt% Ag and Al co-doped ZnO nanoparticles and 50% water + 50% ethylene glycol as base fluid. The obtained thermal conductivity enhancements are comparable to the reported values in the literatures [12,13]. The better dispersion of Ag and Al co-doped ZnO nanoparticles in the 50% Water + 50% EG base fluid attributes to the enhanced thermal conductivity of this nanofluids compared to the other two nanofluids
4. Conclusions The Ag and Al co-doped ZnO nanoparticles are successfully synthesized through a simple wet chemical synthesis route. The ZnO nanoparticle formation has been confirmed through EDS and XRD analysis. The homogeneous doping Ag and Al in ZnO nanoparticles are revealed by x-ray elemental mapping. The severe agglomeration of synthesized ZnO nanoparticles warrants combined ultrasonication and magnetic stirring for uniform distribution of nanoparticles in the base fluid. The effect of base fluid concentration on the thermal conductivity enhancement of nanofluids has been studied by varying the EG and water percentage in the base fluid. The nanofluids prepared using three combinations of base fluids with 1% nanoparticle concentration showed a thermal conductivity enhancement of 12–37% on comparing with its base fluids. The maximum thermal conductivity enhancement of 37.28% is shown in nanofluids with 50% EG + 50%water as base fluid.
References [1] S. Lee, S.U.S. Choi, S. Li, J.A. Eastman, Measuring thermal conductivity of fluids containing oxide nanoparticles, J. Heat Transfer ASME 121 (1999) 280–289. [2] X. Wang, X. Xu, S.U.S. Choi, Thermal conductivity of nanoparticle-fluid mixture, J Thermophys. Heat Transfer 13 (1999) 474–480. [3] S.P. Jang, S.U.S. Choi, Role of Brownian motion in the enhanced thermal conductivity of nanofluids, Appl. Phys. Lett. 84 (2004) 4316. [4] R.V. Pinto, F.A.S. Fiorelli, Review of the mechanisms responsible for heat transfer enhancement using nanofluids, Appl. Therm. Eng. 108 (2016) 720– 739. [5] F. Khan, S.H. Baek, J.H. Kim, Enhanced charge transport properties of Ag and Al co-doped ZnO nanostructures via solution process, J. Alloys Compd. 682 (2016) 232–237.
Please cite this article as: A. R. Arivalagan, V. Karthik, R. Ramji et al., Synthesis and characterization of Ag and Al doped ZnO dispersed nanofluids for heat transfer applications, Materials Today: Proceedings, https://doi.org/10.1016/j.matpr.2019.09.130
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A.R. Arivalagan et al. / Materials Today: Proceedings xxx (xxxx) xxx
[6] J.N. Hasnidawani, H.N. Azlina, H. Norita, N.N. Bonnia, S. Ratimand, E.S. Ali, Synthesis of ZnO nanostructures using sol-gel method, Proc. Chem. 19 (2016) 211–216. [7] J. Chung, J.P. Leonard, I. Nettleship, J.K. Lee, Y. Soong, D.V. Martello, M.K. Chyu, Characterization of ZnO nanoparticle suspension in water: effectiveness of ultrasonic dispersion, Powder Technol. 194 (2009) 75–80. [8] W. Yu, H. Xie, L. Chen, Y. Li, Investigation of thermal conductivity and viscosity of ethylene glycol based ZnO nanofluids, Thermochim Acta 491 (2009) 92–96. [9] K.S. Suganthi, V. Leela Vinodhan, K.S. Rajan, Heat transfer performance and transport properties of ZnO–ethylene glycol and ZnO–ethylene glycol–water nanofluid coolants, Appl Energy 135 (2014) 548–559.
[10] H. Xie, W. Yu, Y. Li, L. Chen, Discussion on the thermal conductivity enhancement of nanofluids, Nanoscale Res. Lett. 6 (2011) 124. [11] M.J. Akhtar, M. Ahamed, S. Kumar, A. Ahmad, S.A. Alrokayan, Zinc oxide nanoparticles selectively induce apoptosis in human cancer cells through reactive oxygen species, Int. J. Nanomed. 7 (2012) 845–857. [12] W. Yu, H. Xie, L. Chen, Y. Li, Investigation of thermal conductivity and viscosity of ethylene glycol based ZnO nanofluid, Thermochim. Acta 491 (2009) 92–96. [13] G.J. Lee, C.K. Kim, M.K. Lee, C.K. Rhee, S. Kim, C. Kim, Thermal conductivity enhancement of ZnO nanofluid using a one-step physical method, Thermochim. Acta 542 (2012) 24–27.
Please cite this article as: A. R. Arivalagan, V. Karthik, R. Ramji et al., Synthesis and characterization of Ag and Al doped ZnO dispersed nanofluids for heat transfer applications, Materials Today: Proceedings, https://doi.org/10.1016/j.matpr.2019.09.130
Contents lists available at ScienceDirect
Materials Today: Proceedings journal homepage: www.elsevier.com/locate/matpr
Synthesis and characterization of Ag and Al doped ZnO dispersed nanofluids for heat transfer applications Aravinth Raj Arivalagan a,⇑, V. Karthik b, R. Ramji b, P.G. Venkatakrishnan c a
Materials Engineering and Nanotechnology, Politecnico Di Milano, Piazza Leonardo da Vinci, 32, 20133 Milano, MI, Italy Department of Metallurgical and Materials Engineering, National Institute of Technology, Tiruchirappalli 620015, Tamil Nadu, India c Department of Mechanical Engineering, Mahendra Engineering College, Mallasamudram, Namakkal 637503, Tamil Nadu, India b
a r t i c l e
i n f o
Article history: Received 16 August 2019 Accepted 17 September 2019 Available online xxxx Keywords: Nanofluids Transient hot wire technique ZnO nanoparticles Al and Ag doping Ethylene glycol + water
a b s t r a c t In this work, Ag and Al co-doped ZnO nanoparticles have been prepared through chemical synthesis route using zinc acetate, silver nitrate and aluminium nitrate. The synthesized nanoparticles are characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The nanofluids are prepared by dispersing 1 wt% of Al and Ag doped ZnO nanoparticles in ethylene glycol (EG)-water (W) mixture. The effect of base fluid on the thermal conductivity enhancement of the nanofluids has been studied by employing three different EG + Water mixtures namely, 25% EG-75% Water, 50% EG-50% Water and 75% EG-25% Water as base fluids. The nanoparticles are homogeneously dispersed in base fluids by using combined magnetic stirring and ultrasonication. The thermal conductivity of the nanofluids are measured through transient hot-wire technique. It is observed that the addition of small amount of Al and Ag doped ZnO nanoparticles to the ethylene glycol-water mixture increases the thermal conductivity of the base fluid. The 50% EG-50 Water mixture showed highest thermal conductivity enhancement of 37% compared to other base fluids when 1% Al and Ag doped ZnO nanoparticles are dispersed. Ó 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International conference on Materials and Manufacturing Methods.
1. Introduction The research and development on nanotechnology have been growing steadily in the fields of science and technology in the recent decades. The enhancement of the thermal properties in the areas of industrial cooling, microelectronics and energy storage is made possible with the invention of nanofluids which are nanoparticles dispersed in fluids such as water, ethylene glycol, etc [1,2]. Different mechanisms like Brownian motion of nanoparticles, formation of an interface layer around the nanoparticle and particle clustering are responsible for the enhancement in the thermal properties of the nanofluids when compared to their base fluids [3,4]. The thermal conductivity of the nanoparticles plays an important role in thermal conductivity enhancement of the nanofluids. The metallic particles dispersed nanofluids will have better thermal properties on comparison to the nonmetallic particles dispersed nanofluids. It is known fact that the transport prop⇑ Corresponding author. E-mail address: [email protected] (A.R. Arivalagan).
erties of the semiconductor particles may be improved by the doping process [5]. The present work focus on the Ag and Al codoped ZnO semiconductor nanoparticle dispersed nanofluids for heat transfer applications. The laboratory synthesis of ZnO nanoparticles using sol-gel method and their characterization is shown by Hasnidawani et al. [6]. The importance of magnetic and ultrasonic stirring for the monodispersing of the nanoparticles in the fluids is shown by Chung et al. [7]. The ZnO nanofluids with base fluid as water and ethylene glycol is studied by Chung et al. and Yu et al. [7,8]. Suganthi et al. [9] have reported a 33.4% enhancement in the thermal conductivity for ZnO nanofluids. Xie et al. [10] have discussed the effect of nanoparticle loading, base fluid temperature, type of nanoparticle and base fluid, particle size, etc. on the thermal conductivity enhancement of the nanofluids. The effect of base fluid proportion on the thermal conductivity of nanofluids is studied in the present work. In this work aluminium and silver doped zinc oxide nanoparticles were synthesized using simple wet chemical synthesis method, then the nanoparticles were dispersed in a mixture of water and ethylene glycol using magnetic and ultrasonic stirring to produce nanofluids.
https://doi.org/10.1016/j.matpr.2019.09.130 2214-7853/Ó 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International conference on Materials and Manufacturing Methods.
Please cite this article as: A. R. Arivalagan, V. Karthik, R. Ramji et al., Synthesis and characterization of Ag and Al doped ZnO dispersed nanofluids for heat transfer applications, Materials Today: Proceedings, https://doi.org/10.1016/j.matpr.2019.09.130
2
A.R. Arivalagan et al. / Materials Today: Proceedings xxx (xxxx) xxx
Table 1 Three types of nanofluids and their constituents.
2. Materials and methods
Content
Sample A
Sample B
Sample C
Ethylene glycol Distilled water Nanoparticles conc.
50% 50% 1%
75% 25% 1%
25% 75% 1%
2.1. Synthesis of Ag and Al co-doped ZnO nanoparticles The procured zinc acetate, silver nitrate, aluminium nitrate, ammonia and ethylene glycol are directly used without any further pretreatment. In order to synthesize the Ag and Al co-doped ZnO nanoparticles, stock solutions of zinc acetate Zn(CH3COO)22H2O (1 M) was initially prepared. Then 10 ml of silver nitrate solution (0.1 M) is added in 50 ml zinc acetate stock solution under stirring. Then 10 ml of 0.04 M aluminium nitrate solution is added under continuous stirring. To this stock solution 2–3 ml ammonia (0.5 M) solution was added under continuous stirring in order to get the pH value of reactants between 8 and 11. These solutions were transferred into teflon-lined sealed stainless steel autoclaves and maintained at temperature range of 70–75 °C for 2 h under autogenous pressure. It was then allowed to cool naturally to room temperature. After the completion of the reaction, the resulting white solid products were washed with distilled water, filtered and then dried in a laboratory oven at 40 °C. 2.2. Synthesis of nanofluids
Fig. 1. Energy dispersive X-ray spectrum of synthesized Ag and Al co-doped ZnO nanoparticles.
Table 2 Weight% of elements present in the synthesized nanomaterial. Elements
Weight%
Zn O Al Ag
71.66 22.58 3.05 2.71
Ag and Al co-doped ZnO nanoparticles of 1wt% concentration were dispersed in ethylene glycol and water mixture using ultrasonic and magnetic stirring for 60 min. Three types of nanofluids were prepared by varying the volume percentage of ethylene glycol and water mixture in the base fluid as shown in the Table 1. Thermal conductivity of the synthesized nanofluids are measured through transient hot-wire technique using KD2 pro equipment under room temperature and atmospheric pressure. 3. Results and discussion The EDS results of the synthesized nanoparticles are shown in Fig. 1. It clearly shows that the elements present in the synthesized material are zinc, oxygen, silver and aluminium. Table 2 shows the weight percentage of the elements present in the synthesized
Fig. 2. Elemental mapping of synthesized Ag and Al co-doped ZnO nanoparticles.
Please cite this article as: A. R. Arivalagan, V. Karthik, R. Ramji et al., Synthesis and characterization of Ag and Al doped ZnO dispersed nanofluids for heat transfer applications, Materials Today: Proceedings, https://doi.org/10.1016/j.matpr.2019.09.130
A.R. Arivalagan et al. / Materials Today: Proceedings xxx (xxxx) xxx
Fig. 3. SEM image of synthesized Ag and Al co-doped ZnO nanoparticles.
Fig. 4. XRD pattern of synthesized Ag and Al co-doped ZnO nanoparticles.
Table 3 Thermal conductivity of the nanofluid on comparison with its base fluid. Sample
Water %
EG %
Thermal conductivity (W/mK)
Enhancement %
Base fluid A Nanofluid A
25 25
75 75
0.244 0.308
20.78
Base fluid B Nanofluid B
50 50
50 50
0.309 0.493
37.28
Base fluid C Nanofluid C
75 25
25 75
0.388 0.441
12.01
nanomaterial. The EDS results clearly indicates the presence of Ag and Al in the ZnO nanoparticles. The Fig. 2 shows the X-ray elemental mapping of the elements present in the synthesized ZnO nanoparticles. The figures clearly reveal the homogeneous doping of Ag and Al in the ZnO particles. The continuous stirring during the synthesis stage enhanced the uniform distribution of the Ag and Al in ZnO particles. The SEM image of the synthesized ZnO powder sample is presented in Fig. 3. The powder particles are agglomerated, hence combined ultrasonication and magnetic stirring is essential to disintegrate the ZnO nanoparticles during nanofluid preparation. The Fig. 4 shows the XRD pattern of the synthesize ZnO sample. The peaks in the XRD pattern matches well with the zincite (ZnO, JCPDS 5-0664) structure. Akhtar et al. [11] has also obtained similar kind XRD pattern for ZnO nanoparticles. The average crystallite size calculated from the XRD peak using Scherer formula is 28 nm.
3
Fig. 5. Thermal conductivity variation in the different base fluid and their corresponding Nano fluids.
The thermal conductivity of various samples was measured using the transient hot wire technique by KD2 Pro equipment. There is a clear enhancement in the thermal conductivity of the base fluids on addition of synthesized nanoparticles. Table 3 shows the thermal conductivity of the nanofluids and its enhancement percentage in comparison with its base fluids (sample A, B, C). Fig. 5 shows the thermal conductivity of the base fluid and nanofluids. It is evident that a maximum thermal conductivity enhancement of 37.28% is shown by nanofluids prepared with 1 wt% Ag and Al co-doped ZnO nanoparticles and 50% water + 50% ethylene glycol as base fluid. The obtained thermal conductivity enhancements are comparable to the reported values in the literatures [12,13]. The better dispersion of Ag and Al co-doped ZnO nanoparticles in the 50% Water + 50% EG base fluid attributes to the enhanced thermal conductivity of this nanofluids compared to the other two nanofluids
4. Conclusions The Ag and Al co-doped ZnO nanoparticles are successfully synthesized through a simple wet chemical synthesis route. The ZnO nanoparticle formation has been confirmed through EDS and XRD analysis. The homogeneous doping Ag and Al in ZnO nanoparticles are revealed by x-ray elemental mapping. The severe agglomeration of synthesized ZnO nanoparticles warrants combined ultrasonication and magnetic stirring for uniform distribution of nanoparticles in the base fluid. The effect of base fluid concentration on the thermal conductivity enhancement of nanofluids has been studied by varying the EG and water percentage in the base fluid. The nanofluids prepared using three combinations of base fluids with 1% nanoparticle concentration showed a thermal conductivity enhancement of 12–37% on comparing with its base fluids. The maximum thermal conductivity enhancement of 37.28% is shown in nanofluids with 50% EG + 50%water as base fluid.
References [1] S. Lee, S.U.S. Choi, S. Li, J.A. Eastman, Measuring thermal conductivity of fluids containing oxide nanoparticles, J. Heat Transfer ASME 121 (1999) 280–289. [2] X. Wang, X. Xu, S.U.S. Choi, Thermal conductivity of nanoparticle-fluid mixture, J Thermophys. Heat Transfer 13 (1999) 474–480. [3] S.P. Jang, S.U.S. Choi, Role of Brownian motion in the enhanced thermal conductivity of nanofluids, Appl. Phys. Lett. 84 (2004) 4316. [4] R.V. Pinto, F.A.S. Fiorelli, Review of the mechanisms responsible for heat transfer enhancement using nanofluids, Appl. Therm. Eng. 108 (2016) 720– 739. [5] F. Khan, S.H. Baek, J.H. Kim, Enhanced charge transport properties of Ag and Al co-doped ZnO nanostructures via solution process, J. Alloys Compd. 682 (2016) 232–237.
Please cite this article as: A. R. Arivalagan, V. Karthik, R. Ramji et al., Synthesis and characterization of Ag and Al doped ZnO dispersed nanofluids for heat transfer applications, Materials Today: Proceedings, https://doi.org/10.1016/j.matpr.2019.09.130
4
A.R. Arivalagan et al. / Materials Today: Proceedings xxx (xxxx) xxx
[6] J.N. Hasnidawani, H.N. Azlina, H. Norita, N.N. Bonnia, S. Ratimand, E.S. Ali, Synthesis of ZnO nanostructures using sol-gel method, Proc. Chem. 19 (2016) 211–216. [7] J. Chung, J.P. Leonard, I. Nettleship, J.K. Lee, Y. Soong, D.V. Martello, M.K. Chyu, Characterization of ZnO nanoparticle suspension in water: effectiveness of ultrasonic dispersion, Powder Technol. 194 (2009) 75–80. [8] W. Yu, H. Xie, L. Chen, Y. Li, Investigation of thermal conductivity and viscosity of ethylene glycol based ZnO nanofluids, Thermochim Acta 491 (2009) 92–96. [9] K.S. Suganthi, V. Leela Vinodhan, K.S. Rajan, Heat transfer performance and transport properties of ZnO–ethylene glycol and ZnO–ethylene glycol–water nanofluid coolants, Appl Energy 135 (2014) 548–559.
[10] H. Xie, W. Yu, Y. Li, L. Chen, Discussion on the thermal conductivity enhancement of nanofluids, Nanoscale Res. Lett. 6 (2011) 124. [11] M.J. Akhtar, M. Ahamed, S. Kumar, A. Ahmad, S.A. Alrokayan, Zinc oxide nanoparticles selectively induce apoptosis in human cancer cells through reactive oxygen species, Int. J. Nanomed. 7 (2012) 845–857. [12] W. Yu, H. Xie, L. Chen, Y. Li, Investigation of thermal conductivity and viscosity of ethylene glycol based ZnO nanofluid, Thermochim. Acta 491 (2009) 92–96. [13] G.J. Lee, C.K. Kim, M.K. Lee, C.K. Rhee, S. Kim, C. Kim, Thermal conductivity enhancement of ZnO nanofluid using a one-step physical method, Thermochim. Acta 542 (2012) 24–27.
Please cite this article as: A. R. Arivalagan, V. Karthik, R. Ramji et al., Synthesis and characterization of Ag and Al doped ZnO dispersed nanofluids for heat transfer applications, Materials Today: Proceedings, https://doi.org/10.1016/j.matpr.2019.09.130