BARC/2019/E/001 BARC/2019/E/001 PRODUCTION AND CHARACTERIZATION OF COPPER NANOPARTICLES BY EXPLODING WIRE METHOD by Rashmita Das, Basanta Kumar Das and Archana Sharma Pulse Power & Electromagnetics Division 2019 BARC/2019/E/001 GOVERNMENT OF INDIA DEPARTMENT OF ATOMIC ENERGY BARC/2019/E/001 PRODUCTION AND CHARACTERIZATION OF COPPER NANOPARTICLES BY EXPLODING WIRE METHOD by Rashmita Das*, Basanta Kumar Das and Archana Sharma [email protected]* Pulse Power & Electromagnetics Division Atchutapuram, Visakhapatnam-531011 BHABHA ATOMIC RESEARCH CENTRE MUMBAI, INDIA 2019 BARC/2019/E/001 BIBLIOGRAPHIC DESCRIPTION SHEET FOR TECHNICAL REPORT (as per IS : 9400 - 1980) 01 Security classification : Unclassified 02 Distribution : External 03 Report status : New 04 Series : BARC External 05 Report type : Technical Report 06 Report No. : BARC/2019/E/001 07 Part No. or Volume No. : 08 Contract No. : 10 Title and subtitle : Production and characterization of copper nanoparticles by exploding wire method 11 Collation : 45 p., 25 figs., 4 tabs., 3 ills. 13 Project No. : 20 Personal author(s) : Rashmita Das; Basanta Kumar Das; Archana Sharma 21 Affiliation of author(s) : Pulse Power and Electromagnetics Division, Bhabha Atomic Research Centre, Visakhapatnam 22 Corporate author(s): Bhabha Atomic Research Centre, Mumbai - 400 085 23 Originating unit : Pulse Power and Electromagnetics Division, Bhabha Atomic Research Centre, Visakhapatnam 24 Sponsor(s) Name : Department of Atomic Energy Type : Government Contd... BARC/2019/E/001 30 Date of submission : March 2019 31 Publication/Issue date : April 2019 40 Publisher/Distributor : Head, Scientific Information Resource Division, Bhabha Atomic Research Centre, Mumbai 42 Form of distribution : Hard copy 50 Language of text : English 51 Language of summary : English 52 No. of references : 21 refs. 53 Gives data on : Abstract : Copper wire of diameter 0.19mm and 0.26 mm was exploded in atmosphere and 60 vacuum. Experimental system has capacitance of 7.1 micro farad and inductance 700 nH. Energy deposition was measured from voltage and current waveform. Exploded material in air at atmospheric pressure was characterized with XRD. XRD spectrum of the sample collected after explosion in air shows increase in oxidation of copper due to increase in overheating factor. The sample collected after explosion in different pressure values were characterized by XRD, optical microscope, TEM and AFM. Optical microscope image of collected exploded material at the vacuum of 2.3×102 mbar indicate the formation of micro particles. TEM and AFM image of exploded material at 1bar pressure of nitrogen indicate the formation of copper nanoparticles. XRD pattern of the same sample shows the presence of pure copper 70 Keywords/Descriptors : EXPLODING WIRES; COPPER; NANOPARTICLES; X-RAY DIFFRACTION; SPATIAL RESOLUTION; TRANSMISSION ELECTRON MICROSCOPY 71 INIS Subject Category.: S37 99 Supplementary elements : PRODUCTION AND CHARACTERIZATION OF COPPER NANOPARTICLES BY EXPLODING WIRE METHOD Rashmita Das*, Basanta Kumar Das and Archana Sharma Pulse Power & Electromagnetics Division, Bhabha Atomic Research Centre, Atchutapuram, Visakhapatnam-531011 [email protected]* Abstract Copper wire of diameter 0.19 mm and 0.26 mm was exploded in atmosphere and vacuum. Experimental system has capacitance of 7.1 micro farad and inductance 700 nH. Energy deposition was measured from voltage and current waveform. Exploded material in air at atmospheric pressure was characterized with XRD. XRD spectrum of the sample collected after explosion in air shows increase in oxidation of copper due to increase in overheating factor. The sample collected after explosion in different pressure values were characterized by XRD, optical microscope, TEM and AFM. Optical microscope image of collected exploded material at the vacuum of 2.3×102 mbar indicate the formation of micro particles. TEM and AFM image of exploded material at 1bar pressure of nitrogen indicate the formation of copper nanoparticles. XRD pattern of the same sample shows the presence of pure copper. CONTENT 1. INTRODUCTION…………………………………………………………….. ............. 1 2. NANOPARTICLES…………………………………………………………… ............. 1 2.1. Production of Nanoparticles…………………………………….. .................................. 3 2.2. Size Control of Nanoparticles……………………………………… .............................. 4 2.3. Applications of Metallic Nanoparticles……………………… ........................................ 5 3. THEORY……………………………………………………………………… ............. 6 3.1. Basic Solutions of LCR Circuit…………………………………... ................................. 6 3.2. Principle of Electrically Explosion of Wire………………. ............................................ 8 3.3. Optimal Fuse Cross Sectional Area……………………………. .................................... 9 3.4. Optimal Fuse Length…………………………………………………. .......................... 10 4. CHARACTERIZATION……………………………………………………… ............. 10 4.1. Scanning Electron Microscope (SEM)………………………….. .................................. 10 4.2. Transmission Electron Microscopy (TEM)…………………… ..................................... 11 4.3. X-Ray Diffraction (XRD)…………………………………………….. .......................... 11 4.4. Atomic Force Microscopy (AFM)…………………………………. .............................. 13 5. EXPERIMENTAL DETAILS……………………………………………….. ............... 14 5.1. Collection of Nanoparticles Sample………………………… ........................................ 14 5.2. Observation of Explosion in Air………………………………… .................................. 15 5.3. Observation of Explosion in Vacuum………………………….. .................................... 15 6. ISSUES RELATED TO NANOPARTICLES GENERATION BY EXPLODING WIRE METHOD……………………………………………………………………… . 16 7. RISK OF NANOPARTICLES TO HUMAN HEALTH AND ENVIRONMENT…… . 17 8. RESULTS AND DISCUSSION……………………………………………… .............. 18 REFERENCES ………………………………………………………………………. .............. 19 APPENDIX ………………………………………………………………………….. ............... 21 List of Figures Fig.No. Title Page Fig.1 Schematic of Transmission electron microscope 24 Fig.2 Schematic of X ray diffraction 25 Fig.3 Schematic of Atomic force microscope 25 Fig.4 Schematic diagram of the exploding wire circuit 26 Fig.5 Photograph of exploding wire set up for the nanoparticles 26 generation Fig.6. Sample collected by gravitational method 27 Fig.7 Sample collected by Hepa filter 27 Fig.8 Current and voltage waveform for the charging voltage 7.5 kV 28 Fig.9 Current and voltage waveform for the charging voltage 9.5 kV 28 Fig.10 Current and voltage waveform for the charging voltage 10.5 kV 29 Fig.11 Current and voltage waveform for the charging voltage 11.5 kV 29 Fig.12 Energy deposited into the wire with variation of overheating 30 factor Fig.13 X-ray diffraction pattern of the sample for overheating factor 1.3 30 Fig.14 X-ray diffraction pattern of the sample for overheating factor 2.5 31 Fig.15 X-ray diffraction pattern of the sample for overheating factor 2.9 31 Fig.16 X-ray diffraction pattern of the sample for overheating factor 3.8 32 Fig.17 Voltage and current waveform at 4.2× 10-2 mbar of nitrogen gas 32 Fig.18 Voltage and current waveform at 2.3× 102 mbar of nitrogen gas 33 Fig.19 Voltage and current waveform at 103 mbar of nitrogen gas 33 Fig.20 Energy deposited into the wire during wire explosion for various 34 pressures of nitrogen gas Fig.21 XRD spectrum for the exploded material 34 Fig.22 Optical microscope image of exploded material at 2.3× 102 mbar 35 of nitrogen gas pressure Fig.23 SEM image of nanoparticles 35 Fig.24 Transmission electron microscope image of nanoparticles 36 Fig.25 Atomic force image of nanoparticles 36 List of Tables Table Title Page No. Table.1 Experimental parameter for explosion in air 37 Table.2 Grain size variation with overheating factor 37 Table.3 Table of the values of the experimental parameters for 38 explosion in vacuum Table.4 Transition of the copper wire from solid through micro particle 38 dispersion and finally to nanoparticles 1. INTRODUCTION Printed electronics has the potential to enable rapid prototyping and low-cost production of functional circuits. Metal nano-ink is used in applications such as flexible radio frequency identification (RFID) tags, active-matrix LCDs, e-paper, flexible organic light emitting diodes (OLEDs) and wearable electronics [1]. Metal nano-ink consists of metal nanoparticles, an organic binder, a precursor and a solvent. The most important component of metal nano- ink is the metal nanoparticles. The low price, high conductivity and high oxidation resistance are also important issues in printed electronics. Cu nano particles are a promising replacement for Au and Ag nano particles because Cu is 100 times cheaper($7 kg−1) than Ag and possesses a conductivity (1.68 × 10−8 Ω m) between Au (2.44 × 10−8 Ω m) and −8 Ag (1.59 × 10 Ω m). Silver and gold are too expensive, in spite of their oxidation resistance. To synthesize metal nanoparticles, various methods have been used such as Polyol processes [2], Gas phase condensation [3], Thermal plasma [4] and Wire explosion [5-10]. In the polyol process and gas phase condensation methods, the particle size and shape can be elaborately controlled. However, many chemical reactions required and low throughput rate are shortcomings regarding mass production. The thermal plasma method also requires a complex process system with a high energy density, namely strong gradients between the medium carrying the deposition precursor and the surroundings. The wire explosion process has many advantages, such as the simplicity of