1. Korea Atomic Energy Research Institute 2014. 04. 23 Chan-Hee Jung Radiation Research Center for Industry and Environment, Advanced Radiation Technology Institute, KAERI

2. Korea Atomic Energy Research Institute Micropatterning of Metal Nanoparticles Surface Modification of Carbon Nanomaterials Content Brief Introduction to Ion Beam Technology Surface Functionalization and Patterning of Polymer

3. Korea Atomic Energy Research Institute Ion beam technology: - It is based on the physiochemical change in the surface of materials such as polymers, ceramics, and metals induced by a high-energy ion bombardment where large numbers of accelerated ions (positively charged atoms) bombard and penetrate the surface under vacuum. Characteristics of ion beam technology: - High linear energy transfer => Surface-specific treatment & High process efficiency - Precise control of ion penetration depth and concentration => Good reliability - Room temperature and dry process => Low energy consumption & Pollutant reduction Ion beam technology: - It is based on the physiochemical change in the surface of materials such as polymers, ceramics, and metals induced by a high-energy ion bombardment where large numbers of accelerated ions (positively charged atoms) bombard and penetrate the surface under vacuum. Characteristics of ion beam technology: - High linear energy transfer => Surface-specific treatment & High process efficiency - Precise control of ion penetration depth and concentration => Good reliability - Room temperature and dry process => Low energy consumption & Pollutant reduction Brief Introduction to Ion Beam Technology

4. Korea Atomic Energy Research Institute Ion Bombardment Effects on Polymers Controlling chemical, electrical, optical, mechanical, and tribological characteristics.

5. Korea Atomic Energy Research Institute Potential Industrial Applications Optical and electronic fields Biological fields Strain gauges Electro-optical Modulators Light filtersWaveguides Biosensors Artificial boneCell culture dishes Artificial hip joint Biochips

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7. Brief Introduction to Bimolecular Micropatterning Immobilization and patterning of biomolecules: -Immobilization and micropatterning of biomolecules on a solid substrate are essential to a variety of bio-applications including biosensors, tissue engineering, and basic biological studies. Conventional polymers for the immobilization of biomolecules: Immobilization and patterning of biomolecules: -Immobilization and micropatterning of biomolecules on a solid substrate are essential to a variety of bio-applications including biosensors, tissue engineering, and basic biological studies. Conventional polymers for the immobilization of biomolecules: AdvantagesDisadvantages Low cost Bio-inertness due to hydrophobicity Lightweight Mechanical, thermal, and chemical stability Processibility

8. Korea Atomic Energy Research Institute Surface Functionalization Polymer substrates should be subjected to surface functionalization to improve their biocompatibility (hydrophilicity): - Other properties to be improved: wetting, adhesion, printing, etc. General methods for the surface functionalization of polymers: - Corona discharge - Plasma treatment - High energy irradiation (electron beams and ion beam) - Wet chemical treatment Advantages of ion beam-based surface functionalization over others: - Surface specific process with a low penetration depth (~ μm) - Outstanding reliability and controllability - Biocompatible process (No use of any toxic chemicals) - Good chemical stability through covalent bonding Polymer substrates should be subjected to surface functionalization to improve their biocompatibility (hydrophilicity): - Other properties to be improved: wetting, adhesion, printing, etc. General methods for the surface functionalization of polymers: - Corona discharge - Plasma treatment - High energy irradiation (electron beams and ion beam) - Wet chemical treatment Advantages of ion beam-based surface functionalization over others: - Surface specific process with a low penetration depth (~ μm) - Outstanding reliability and controllability - Biocompatible process (No use of any toxic chemicals) - Good chemical stability through covalent bonding

9. Korea Atomic Energy Research Institute Ion beam-based strategies for the formation of biomolecular micropatterns on various polymeric substrates: (1) Mask-assisted ion implantation (2) Ion beam contact lithography (3) Selective ion beam surface grafting Ion beam-based strategies for the formation of biomolecular micropatterns on various polymeric substrates: (1) Mask-assisted ion implantation (2) Ion beam contact lithography (3) Selective ion beam surface grafting Ion Beam-Based Strategy for Biomolecular Patterning

10. Korea Atomic Energy Research Institute Mask-Assisted Ion Implantation Scheme

11. Korea Atomic Energy Research Institute Mask-Assisted Ion Implantation Poly(vinyl chloride)1 x 10 16 ions/cm 2 Surface analysis

12. Korea Atomic Energy Research Institute Mask-Assisted Ion Implantation Formation of cell micropatterns

13. Korea Atomic Energy Research Institute Ion Beam Contact Lithography Scheme

14. Korea Atomic Energy Research Institute Surface Analysis Ion beam contact lithography

15. Korea Atomic Energy Research Institute Formation of cell micropatterns Ion Beam Contact Lithography

16. Korea Atomic Energy Research Institute Selective Ion Beam Surface Grafting Scheme

17. Korea Atomic Energy Research Institute Surface Analysis Selective Ion Beam Surface Grafting

18. Korea Atomic Energy Research Institute Formation of DNA and protein micropatterns Selective Ion Beam Surface Grafting

19. Korea Atomic Energy Research Institute Anthrax toxin (DNA sensor/chip): ~ 10 fg/ml (Detectable limit) Application (I) Selective Ion Beam Surface Grafting

20. Korea Atomic Energy Research Institute Application (II) Liver cancer (Immuno-sensor/chip): ~ 10 pg/ml (Detectable limit) Selective Ion Beam Surface Grafting

21. Korea Atomic Energy Research Institute An facile, efficient, and biocompatible ion beam-based strategies for the immobilization and patterning of biomolecules were introduced: -The surfaces of various polymer substrates can be chemically micropatterned by using ion beam based technologies including the mask-assisted ion implantation, ion beam contact lithography, and selective ion beam surface grafting. -Well-defined micropatterns of biomolecules such cell, DNAs and protein can be achieved on the resulting surface-micropatterned substrate. -These ion beam-based technologies is diversely applicable to biological applications such as fundamental study, tissue engineering, bioassay, biosensors/chips, and microfluidic devices. An facile, efficient, and biocompatible ion beam-based strategies for the immobilization and patterning of biomolecules were introduced: -The surfaces of various polymer substrates can be chemically micropatterned by using ion beam based technologies including the mask-assisted ion implantation, ion beam contact lithography, and selective ion beam surface grafting. -Well-defined micropatterns of biomolecules such cell, DNAs and protein can be achieved on the resulting surface-micropatterned substrate. -These ion beam-based technologies is diversely applicable to biological applications such as fundamental study, tissue engineering, bioassay, biosensors/chips, and microfluidic devices. Summary

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23. Brief Introduction to Patterning of Metal NPs The importance of the metal NPs patterning: - Metal NPs exhibit unique electronic, optical, chemical, mechanical, catalytic, and magnetic properties. - Taking advantage of these unique properties, the arrangement of metal NPs at the specific positions is of great importance to realize novel micro- and nano-devices such as photonic materials, optoelectronic devices, biochemical sensors, and many others. Methods for the formation of metal NPs: - Sedimentation, electrostatic-induced crystallization, photolithography, nanosphere lithography, self-assembly method, wet coating, template-assisted electro- deposition, and so on. Despite this increased effort and significant advance in the patterning of metal NPs, the development of a more convenient, reliable, and mass-producible technology is still highly demanded for the practical applications. The importance of the metal NPs patterning: - Metal NPs exhibit unique electronic, optical, chemical, mechanical, catalytic, and magnetic properties. - Taking advantage of these unique properties, the arrangement of metal NPs at the specific positions is of great importance to realize novel micro- and nano-devices such as photonic materials, optoelectronic devices, biochemical sensors, and many others. Methods for the formation of metal NPs: - Sedimentation, electrostatic-induced crystallization, photolithography, nanosphere lithography, self-assembly method, wet coating, template-assisted electro- deposition, and so on. Despite this increased effort and significant advance in the patterning of metal NPs, the development of a more convenient, reliable, and mass-producible technology is still highly demanded for the practical applications.

24. Korea Atomic Energy Research Institute Ion beam-based strategies for the formation of metal (Ag, Au, etc.) NPs: (1) Ion beam contact lithography and plasma etching (2) Selective ion beam surface grafting and layer-by-layer (LbL) deposition Ion beam-based strategies for the formation of metal (Ag, Au, etc.) NPs: (1) Ion beam contact lithography and plasma etching (2) Selective ion beam surface grafting and layer-by-layer (LbL) deposition Ion beam-based strategy for Patterning of Metal NPs

25. Korea Atomic Energy Research Institute Plasma Etching Plasma is a ionized gas composed of equal numbers of positive and negative charges and a different number of unionized molecules. Plasma etching : - It is a process that removes a material from a surface through a plasma-induced physiochemical reaction. - Typical etching gas for the removal of polymers are oxygen (O 2 ) and hydrogen (H 2 ). Plasma is a ionized gas composed of equal numbers of positive and negative charges and a different number of unionized molecules. Plasma etching : - It is a process that removes a material from a surface through a plasma-induced physiochemical reaction. - Typical etching gas for the removal of polymers are oxygen (O 2 ) and hydrogen (H 2 ).

26. Korea Atomic Energy Research Institute Layer-by-Layer Deposition Layer-by-layer (LbL) deposition is a convenient and powerful technique for the construction of multiple-layered metal nanoparticles on a curved substrate. It is based on a sequential adsorption of complementary materials through electrostatic interaction, hydrogen bonding, and other complementary interactions: - It is typically performed using alternating dip-coating of a substrate in positively and negatively charged material solutions. Layer-by-layer (LbL) deposition is a convenient and powerful technique for the construction of multiple-layered metal nanoparticles on a curved substrate. It is based on a sequential adsorption of complementary materials through electrostatic interaction, hydrogen bonding, and other complementary interactions: - It is typically performed using alternating dip-coating of a substrate in positively and negatively charged material solutions.

27. Korea Atomic Energy Research Institute Ion Beam Contact Lithography and Plasma Etching Scheme

28. Korea Atomic Energy Research Institute Formation of Pluronic/Au NPs Patterns Ion Beam Contact Lithography and Plasma Etching

29. Korea Atomic Energy Research Institute Formation of Au NPs Patterns Ion Beam Contact Lithography and Plasma Etching

30. Korea Atomic Energy Research Institute Selective Ion Beam Surface Grafting and LbL Deposition Scheme

31. Korea Atomic Energy Research Institute Formation of PAA patterns on a fluoropolymer film Selective Ion Beam Surface Grafting and LbL Deposition

32. Korea Atomic Energy Research Institute Formation of GNPs patterns on a PAA-patterned PFA Selective Ion Beam Surface Grafting and LbL Deposition

33. Korea Atomic Energy Research Institute Electrical chrematistic of GNPs patterns on a PAA-patterned PFA Selective Ion Beam Surface Grafting and LbL Deposition

34. Korea Atomic Energy Research Institute An simple and efficient ion beam strategies for patterning of metal nanoparticles were introduced: -Well-defined micropatterns of metal nanoparticles can be established on the organic and inorganic substrates by using (1) ion beam contact lithography and plasma etching and (2) selective ion beam surface grafting and layer-by-layer (LbL) deposition. -These ion beam-based technologies can be applied to prepare patterned arrays of various metal nanoparticles, which are crucial for the electrical and biological applications. An simple and efficient ion beam strategies for patterning of metal nanoparticles were introduced: -Well-defined micropatterns of metal nanoparticles can be established on the organic and inorganic substrates by using (1) ion beam contact lithography and plasma etching and (2) selective ion beam surface grafting and layer-by-layer (LbL) deposition. -These ion beam-based technologies can be applied to prepare patterned arrays of various metal nanoparticles, which are crucial for the electrical and biological applications. Summary

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37. Brief Introduction to CNTs Applications of CNTs: - Polymer nanocomposites, field-effect transistor, memory, battery, supercapacitor, solar cell, water filter, biosensor, medical devices etc. However, the lack of solubility and the difficult manipulation in any solvents have imposed great limitations to the use of CNT. Applications of CNTs: - Polymer nanocomposites, field-effect transistor, memory, battery, supercapacitor, solar cell, water filter, biosensor, medical devices etc. However, the lack of solubility and the difficult manipulation in any solvents have imposed great limitations to the use of CNT. Carbon Nanotubes (CNTs): - Cylindrically-shaped graphitic nanostructures that have radii as small as tenths of nanometers. - Primary classification based on the number of walls: single-walled carbon nanotubes (SWCNTs), double-walled carbon nanotubes (DWCNTs), and multi-walled carbon nanotubes (MWCNTs) - Outstanding mechanical, thermal, chemical, and electronic properties MWCNT SWCNT DWCNT

38. Korea Atomic Energy Research Institute Radiation-Induced Graft polymerization Typical strategies for the surface functionalization of CNTs: (a) Covalent attachment of chemical groups (b) Non-covalent adsorption or wrapping of various functional molecules Covalent grafting of polymers on the CNTs: - It has been preferred due to rendering well-dispersibility in various solvents even at a low degree of functionalization. Two methods for covalent grafting of polymers on the CNTs: - “Grafting From” method without steric hindrance effect is preferred. - “Grafting From” techniques include anionic polymerization, reversible addition- fragmentation chain transfer polymerization ring-opening polymerization, atom transfer radical polymerization, radiation-induced polymerization, and others. Typical strategies for the surface functionalization of CNTs: (a) Covalent attachment of chemical groups (b) Non-covalent adsorption or wrapping of various functional molecules Covalent grafting of polymers on the CNTs: - It has been preferred due to rendering well-dispersibility in various solvents even at a low degree of functionalization. Two methods for covalent grafting of polymers on the CNTs: - “Grafting From” method without steric hindrance effect is preferred. - “Grafting From” techniques include anionic polymerization, reversible addition- fragmentation chain transfer polymerization ring-opening polymerization, atom transfer radical polymerization, radiation-induced polymerization, and others.

39. Korea Atomic Energy Research Institute Radiation-Induced Graft Polymerization (RIGP) Advantages of radiation-induced graft polymerization over others: - The functionalized material is free from residuals such as initiators, monomers, or catalysts. - The reaction is performed at room temperature and more controllable than chemical operation. - The grafting can be carried out in bulk, solution, emulsion, and even at a solid state. Advantages of radiation-induced graft polymerization over others: - The functionalized material is free from residuals such as initiators, monomers, or catalysts. - The reaction is performed at room temperature and more controllable than chemical operation. - The grafting can be carried out in bulk, solution, emulsion, and even at a solid state.

40. Korea Atomic Energy Research Institute Surface Functionalization of CNTs by RIGP: Scheme

41. Korea Atomic Energy Research Institute Surface Functionalization of CNTs by RIGP: Analysis (I)

42. Korea Atomic Energy Research Institute Surface Functionalization of CNTs by RIGP: Analysis (II)

43. Korea Atomic Energy Research Institute Surface Functionalization of CNTs by RIGP: Application

44. Korea Atomic Energy Research Institute Summary Surface functionalization of MWCNT for a biological application by radiation-induced graft polymerization was introduced: - The polymer can be covalently introduced on the surface of MWCNT by radiation-induce graft polymerization. - The polymer-grafted MWCNT exhibits a much better dispersibility than control MWCNT. - For the biological application, biomolecules such as DNAs and proteins can be successfully immobilized onto the polymer-grafted MWCNT. -The polymer-grafted MWCNT developed in this study can be utilized in the various applications such as composites, coatings, paints and inks, biomaterials, and electronic materials. Surface functionalization of MWCNT for a biological application by radiation-induced graft polymerization was introduced: - The polymer can be covalently introduced on the surface of MWCNT by radiation-induce graft polymerization. - The polymer-grafted MWCNT exhibits a much better dispersibility than control MWCNT. - For the biological application, biomolecules such as DNAs and proteins can be successfully immobilized onto the polymer-grafted MWCNT. -The polymer-grafted MWCNT developed in this study can be utilized in the various applications such as composites, coatings, paints and inks, biomaterials, and electronic materials.

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46. Brief Introduction to Graphene Definition: -Two-dimensional atomic layer consisting of hexagonally arrayed sp 2 -bonded carbon atoms. Unique properties : -Excellent mechanical, electrical, thermal, and optical properties. Diverse applications : Definition: -Two-dimensional atomic layer consisting of hexagonally arrayed sp 2 -bonded carbon atoms. Unique properties : -Excellent mechanical, electrical, thermal, and optical properties. Diverse applications :

47. Korea Atomic Energy Research Institute Synthesis of Graphene Methods for the synthesis of graphene Reduction of graphene oxide (GO) - The most convenient route to produce the graphene on a large scale. An eco-friendly, efficient, and simple method for the mass production of graphene at room temperature should be required. Methods for the synthesis of graphene Reduction of graphene oxide (GO) - The most convenient route to produce the graphene on a large scale. An eco-friendly, efficient, and simple method for the mass production of graphene at room temperature should be required. -Chemical method : N 2 H 4, NaBH 4 -Heat treatment -Solvothermal method -Electrochemical method -Photocatalytic method -Requirement of toxic and explosive chemical reducing agents -High temperature process -Formation of impurities -Low reduction capability DrawbacksReduction method But !!!

48. Korea Atomic Energy Research Institute Radiation-Induced Reduction of GO Advantages of radiation-induced reduction of GO over others: - No need of toxic and explosive chemical reducing agents - Room temperature process - No formation of impurities - Easy controllability - Mass productivity Advantages of radiation-induced reduction of GO over others: - No need of toxic and explosive chemical reducing agents - Room temperature process - No formation of impurities - Easy controllability - Mass productivity

49. Korea Atomic Energy Research Institute Radiation-Induced Reduction of GO: Scheme

50. Korea Atomic Energy Research Institute Radiation-Induced Reduction of GO: Optical Analysis RRGOs The absorption peaks of the RRGOs are shifted to a longer wavelength with an increasing absorbed dose.

51. Korea Atomic Energy Research Institute Radiation-Induced Reduction of GO: Optical Analysis RRGOs The thermal stability of the RRGOs was improved with an increasing absorbed dose.

52. Korea Atomic Energy Research Institute Radiation-Induced Reduction of GO: XPS Analysis The intensities of the oxygen-containing functionalities present in the RRGOs (50 ~ 1500 kGy) are reduced with an increasing absorbed dose.

53. Korea Atomic Energy Research Institute Radiation-Induced Reduction of GO: XRD Analysis RRGOs The broad peak for the RRGOs appears at 22.5 o.

54. Korea Atomic Energy Research Institute Radiation-Induced Reduction of GO: Raman Analysis RRGOs The intensity ratio of the D band to the G band(I D /I G ) of the RRGOs increases with an increasing dose.

55. Korea Atomic Energy Research Institute Radiation-Induced Reduction of GO: TEM Analysis The crystalline structure is formed in the RRGO.

56. Korea Atomic Energy Research Institute Radiation-Induced Reduction of GO: Conductivity Measurement The electrical conductivity of the RRGOS increase with an increasing dose

57. Korea Atomic Energy Research Institute Radiation-Induced Reduction of GO: Plausible Mechanism The formed electrons can cause a deoxygenation of GO, thus resulting in the reduction of GO and the amounts of the formed reductive electrons (e) rely on the absorbed dose.

58. Korea Atomic Energy Research Institute An eco-friendly, efficient, and simple radiation-based strategy for the reduction of graphene oxide was introduced: - The graphene can be prepared by radiation-induced reduction of GO (RRGO). - This rapid, facile, and eco-friendly method is a promising route for the mass production of RGO, which is desirable for various applications such as composites, coatings, paints and inks, biomaterials, and electronic materials. An eco-friendly, efficient, and simple radiation-based strategy for the reduction of graphene oxide was introduced: - The graphene can be prepared by radiation-induced reduction of GO (RRGO). - This rapid, facile, and eco-friendly method is a promising route for the mass production of RGO, which is desirable for various applications such as composites, coatings, paints and inks, biomaterials, and electronic materials. Summary

59. Korea Atomic Energy Research Institute Thank you for your attention!!