,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,A member of NSG Group,1,A member of NSG Group1,Application of Inorganic Chemistry in Industry,Flat Glass and Coatings On Glass,Dr Troy Manning,Advanced Technologist, On-line Coatings,Pilkington European Technical Centre,Hall Lane,Lathom,UK,troy.manningpilkington,2,Application of Inorganic Chemi,Outline,Overview of Flat Glass industry and NSG/Pilkington,Flat Glass manufacture,Float Glass Process,Coating technology within the glass industry,Chemical Vapour Deposition,Examples of on line coating applications,Low Emissivity/Solar Control,Self Cleaning,Summary,Suggested Reading,3,OutlineOverview of Flat Glass,Global Flat Glass Market,Global Market,37 million tonnes (4.4 billion sq. m),Building Products 33 m tonnes - Automotive 4m tonnes,Of which,24 million = high quality float glass,3 million = sheet,2 million = rolled,8 million = lower quality float (mostly China),Global Value,At primary manufacture level,15 billion,At processed level,50 billion,4,Global Flat Glass MarketGlobal,NSG and Pilkington combined,A global glass leader the pure play in Flat Glass,Combined annual sales c. 4 billion,Equal to Asahi Glass in scale, most profitable in Flat Glass,Ownership/interests in 46 float lines,6.4 million tonnes annual output,Widened Automotive customer base,36,000 employees worldwide,Manufacturing operations in 26 countries,Sales in 130+ countries,5,NSG and Pilkington combinedA g,Manufacture of Flat Glass,Four main methods,Plate Glass (1688) molten glass poured on to a flat bed, spread, cooled and polished,Sheet Glass (1905) continuous sheet of glass drawn from tank of molten glass,Rolled Glass (1920) molten glass poured onto to two rollers to achieve an even thickness, making polishing easier. Used to make patterned and wired glass.,Float Glass (1959) molten glass poured onto bed of molten tin and drawn off in continuous ribbon. Gives high quality flat glass with even thickness and fire polish finish. 320 float-glass lines worldwide,6,Manufacture of Flat GlassFour,Melting furnace,Float bath,Cooling lehr,Continuos ribbon of glass,Cross cutters,Large plate lift-off devices,Small plate lift-off devices,Raw material feed,The Float-Glass Process,Operates non-stop for 10-15 years,6000 km/year,0.4 mm-25 mm thick, up to 3 m wide,7,Melting furnaceFloat bathCooli,The Float Glass Process,8,The Float Glass Process8,Raw materials,9,Raw materials9,Melting Furnace,10,Melting Furnace10,Float Bath,11,Float Bath11,Float Glass Plant,12,Float Glass Plant12,The Float-Glass Process,Fine-grained ingredients, closely controlled for quality, are mixed to make batch, which flows as a blanket on to molten glass at 1500 C in the melter. The furnace contains 2000 tonnes of molten glass.,After about 50 hours, glass from the melter flows gently over a refractory spout on to the mirror-like surface of molten tin, starting at 1100C and leaving the float bath as a solid ribbon at 600C.,Despite the tranquillity with which float glass is formed, considerable stresses are developed in the ribbon as it cools.,13,The Float-Glass ProcessFine-gr,Raw Materials,Oxide % in glass Raw material source,SiO,2,72.2Sand,Na,2,O13.4Soda Ash (Na,2,CO,3,),CaO8.4Limestone (CaCO,3,),MgO4.0Dolomite (MgCO,3,.CaCO,3,),Al,2,O,3,1.0Impurity in sand, Feldspar or Calumite,Fe,2,O,3,0.11Impurity in sand or Rouge (Fe,2,O,3,),SO,3,0.20Sodium sulphate,C0.00Anthracite,14,Raw MaterialsOxide % in gl,Raw materials,SiO,2,Very durable, BUT high melting point (1700C)!,+ Na,2,OMelts at a lower temperature, BUT dissolves in water!,+ CaOMore durable, BUT will not form in bath without crystallisation,+ MgOGlass stays as a super-cooled liquid in bath, no crystallisation,+ Al,2,O,3,Adds durability,+ Fe,2,O,3,Adds required level of green colour for customer,15,Raw materials SiO2Very durabl,Chemistry of Glass,Important glassmaking chemistry: basic reactions,Na,2,CO,3,+ SiO,2,1500C,Na,2,SiO,3,+ CO,2,Na,2,SiO,3,+ x SiO,2,Na,2,SO,4,(Na,2,O)(SiO,2,),(x+1),Digestion,16,Chemistry of GlassImportant gl,Composition of Glass,17,Composition of Glass17,Structure of Glass,Random network of SiO,4,-,tetrahedral units.,Na-O enter Si-O network according to valency Network Formers,Ca and Mg Network Modifiers make structure more complex to prevent crystallisation,18,Structure of GlassRandom netwo,Body-tinted Glass,Ion,Resulting Colour of Glass,Ferrous (Fe,2+,),Blue,Ferric (Fe,3+,),Yellow,Fe,2+,+ Fe,3+,Green,Selenium (SeO,2,),Bronze,Cobalt (Co,2+,),Grey/Blue,Nickel (Ni,2+,),Grey,19,Body-tinted GlassIonResulting,CIE L a* b* colour space,20,CIE L a* b* colour space20,CIE L a* b* colour space,21,CIE L a* b* colour space21,Functions of a Window,Light in homes, offices,Light out shops, museum displays,Heat in heating dominated climates,Heat out cooling dominated climates,Can change properties of glass by applying coatings to the surface,22,Functions of a WindowLight in,Making a window functional - coatings,A wide variety of coating technologies are utilised by the glass industry,Spray Pyrolysis,Powder Spray,Chemical Vapour Deposition,Sputter Coating,Thermal Evaporation Coatings,Sol Gel Coatings,These are applied,On Line i.e. as the glass is produced on the float line,Off Line i.e. coating not necessarily produced at the same location,23,Making a window functional - c,Variations of CVD,Atmospheric Pressure APCVD,Low Pressure - LPCVD,Aerosol Assisted - AACVD,Metalorganic MOCVD,Combustion/Flame CCVD,Hot Wire/Filament HWCVD/HFCVD,Plasma Enhanced - PECVD,Laser Assisted LACVD,Microwave Assisted MWCVD,Atomic Layer Deposition ALD,24,Variations of CVDAtmospheric P,Chemical Vapour Deposition,25,Chemical Vapour Deposition25,Chemical Vapour Deposition,Main gas flow region,Gas Phase Reactions,Surface Diffusion,Desorption of,Film Precursor,By Products,Diffusion,to surface,26,Chemical Vapour DepositionMain,Chemical Vapour Deposition,Animation kindly supplied by Dr. Warren Cross, University of Nottingham,27,Chemical Vapour DepositionAnim,CVD processes and parameters,Process,Parameters,Transport,Precursors,Gas phase reaction,Pressure, temperature, flow conditions, boundary layer thickness, gas phase concentration, precursors, carrier gas,Diffusion,Pressure, temperature, flow conditions, boundary layer thickness, gas phase concentration,Adsorption,Temperature, gas phase concentration, number and nature of sites,Surface reaction,Temperature, nature of surface,Desorption of by-products,Temperature, pressure, nature of surface,Diffusion to lattice site,Temperature, surface mobility, number of vacant sites,28,CVD processes and parametersPr,CVD Precursor Properties,Volatile gas, liquid, low melting point solid, sublimable solid,Pure,Stable under transport,React/Decompose cleanly to give desired coating minimise contaminants,Can be single source or dual/multi-source,29,CVD Precursor PropertiesVolati,CVD Precursors,Single Source pyrolysis (thermal decomposition),e.g Ti(OC,2,H,5,),4, TiO,2,+ 4C,2,H,4,+ 2H,2,O (400 C),Oxidation e.g SiH,4,(g) + O,2,(g) SiO,2,(s) + 2H,2,(g),Reduction e.g. WF,6,(g) + 3H,2,(g) W(s) + 6HF(g),Dual source e.g. TiCl,4,(g) + 4EtOH(g) TiO,2,(s) + 4HCl(g) + 2EtOEt(g),30,CVD PrecursorsSingle Source ,Dual Source and Single Source Precursors,Film,Dual Source,Single Source,GaAs,GaCl,3,+ AsH,3,Me,2,Ga(AsH,2,),TiN,TiCl,4,+ NH,3,Ti(NMe,2,),4,WSi,WCl,6,+ SiH,4,W(SiR),4,TiO,2,TiCl,4,+ H,2,O,Ti(O,i,Pr),4,CdSe,CdMe,2,+ H,2,Se,Cd(SeR),2,31,Dual Source and Single Source,Transport of Precursors,Bubbler for liquids and low melting solids,Direct Liquid Injection syringe and syringe driver for liquids and solutions,Sublimation for solids hot gas passed over heated precursor,Aerosol of precursor solutions,32,Transport of PrecursorsBubbler,Effect of Temperature on Growth Rate,Independent of temperature,33,Effect of Temperature on Growt,Flow conditions,Laminar Flow regime,Turbulent Flow Regime,34,Flow conditionsLaminar Flow re,Reynolds Number,Dimensionless number describing flow conditions,r =,Mass density related to conc,n,and partial pressure,u = average velocity,= viscosity,L = relevant length, related to reactor dimensions,If R,e, 1000 fully turbulent flow,Reality is between the two extremes,35,Reynolds NumberDimensionless n,Dimensionless Numbers,Reduces the number of parameters that describe a system,Makes it easier to determine relationships experimentally,For example: Drag Force on a Sphere,Variables: Force =,f,(,velocity, diameter, viscosity, density),Can be reduced to 2 “dimensionless groups”:,Drag coefficient (,C,D,) and Reynolds number (,R,e,),36,Dimensionless NumbersReduces t,Dimensionless Numbers,Laminar flow regime,Turbulent flow regime,Experimental values of C,D,for spheres in fluid flows at various R,e,37,Dimensionless NumbersLaminar f,Boundary Layer gas velocity,Frictional forces against reactor walls decrease gas velocity,The boundary layer thickness can be estimated from:,38,Boundary Layer gas velocityF,Boundary Layer - temperature,Contact with hot surfaces increases temperature,39,Boundary Layer - temperatureCo,Boundary Layer precursor concentration,Depletion of precursor decreases gas phase concentration,40,Boundary Layer precursor con,Nucleation and Growth,Van der Waals type adsorption of precursor to substrate,Precursors then diffuse across surface,Precursors diffuse across boundary layer to surface,And can be desorbed back into main gas flow,Or can find low energy binding sites to coalesce into film,Main Gas Flow,41,Nucleation and GrowthVan der W,Nucleation and Growth,Substrate Temperature,Growth Rate,Surface Diffusion,Crystallinity,Low,High,Slow relative flux of precursors,Amorphous no crystalline structure,High,Low,Fast relative to flux of precursors,Epitaxial replicates substrate structure,Intermediate,Intermediate,Intermediate,Polycrystalline,42,Nucleation and GrowthSubstrate,Growth Mechanisms,(b) Frank - van der Merwe,Layer growth,(c) Stranski - Kastanov,Mixed layered and island,growth,(,a) Volmer - Weber,Island growth,43,Growth Mechanisms(b) Frank - v,Thin Film Analysis,Many techniques are used to characterise thin films,Examples include,XRD crystallinity, phase,XRR layer thickness, layer roughness,SEM/EDX/WDX morphology, thickness, composition,Raman phase, bonding,FTIR phase, bonding,XPS composition, depth profiling, doping,SIMS composition, depth profiling, doping,AFM roughness, surface morphology,TEM crystalline structure, crystal defects,Analysis of functional properties,44,Thin Film AnalysisMany techniq,CVD on Glass,For on-line coating of glass we require:,High growth rates required thickness in 100 nm/s possible,Low precursor efficiency 10%,SiC,x,O,y,(70 nm),SnO,2,:F (350 nm),Glass,SiH,4,+ C,2,H,4,+ CO,2, SiC,x,O,y,+ H,2,O + other by-products,Used as colour suppression and barrier layer,57,CVD of SnO2:FSnCl4 + H2O + HF,Low Emissivity Coating,Generally based on SnO,2,:F (,T,ransparent,C,onductive,O,xide),SiCO under layer used as colour suppressant,58,Low Emissivity CoatingGenerall,Low-E and Solar Control Coatings,59,Low-E and Solar Control Coatin,Self-Cleaning Glass,Two mechanisms:,Super hydrophilicity,Photocatalytic degradation of organic matter.,TiO,2,coating,60,Self-Cleaning GlassTwo mechani,Superhydrophilicity,Oxygen vacancies,T,i,O,-,T,i,O,T,i,H,T,i,T,i,T,i,H,+,T,i,O,T,i,O,T,i,T,i,O,T,i,O,T,i,H,H,H,2,O,(,O,H,-,H,+,),Water droplets,Uniform water film,UV illumination time,Contact angle,o,o,o,o,o,o,o,dark,UV,61,SuperhydrophilicityOxygen vaca,Photocatalytic Activity,Ultra band gap irradiation of TiO,2,Generation of electron hole in valence band,Hole migrates to the surface and results in oxidation of organic material,V,a,l,e,n,c,e,B,a,n,d,C,o,n,d,u,c,t,a,n,c,e,B,a,n,d,O,x,i,d,a,t,i,o,n,R,e,d,u,c,t,i,o,n,A,A,+,B,B,-,h,+,h,n,62,Photocatalytic ActivityUltra b,Semi-conductor Photocatalysis,A. Mills, S Le Hunte,J. Photochem. Photobiol A, 2019,108, 1-35.,63,Semi-conductor PhotocatalysisA,CVD of Activ,TM,SiO,2,(30 nm),TiO,2,(17 nm),Glass,SiH,4,+ O,2,+ C,2,H,4, SiO,2,+ by-products,Used as barrier layer to prevent diffusion of Na ions into TiO,2,layer,TiCl,4,+ EtOAc, TiO,2,+ HCl + organic by-products,Laminar Flow regime,Reasonable growth rates and precursor efficiency,64,CVD of ActivTMSiO2 (30 nm)TiO2,Activ,TM,65,ActivTM65,Activ,TM,66,ActivTM66,Activ,TM,67,ActivTM67,Superhydrophilicity,15 mins UV Exposure,30 mins UV Exposure,45 mins UV Exposure,Before UV Exposure,68,Superhydrophilicity15 mins UV,Photocatalytic Effect,UV-Absorption,O,2,-,OH,*,Organic Soil,H,2,O + CO,2,Glass,Barrier Layer,TiO,2,- Layer,69,Photocatalytic Effect UV-Abso,Photocatalytic Effect,The photoactivity of the coating can be measured by monitoring the decomposition of a standard contaminant,A thin film of stearic acid (n-octadecanoic acid, 200) is applied from a methanol solution onto the coating,Stearic acid used as a typical organic contaminant,FTIR (Fourier transform infra-red spectroscopy) used to detect C-H stretch of stearic acid,C-H absorption intensity measured after varying UV exposure,70,Photocatalytic EffectThe photo,Stearic Acid Decomposition,C-H Absorption Zero UV exposure,C-H Absorption 60 mins UV exposure,UV 0.77W/m,2,340nm,71,Stearic Acid DecompositionC-H,Pilkington Activ,TM,72,Pilkington ActivTM72,Summary,Scale of the Global Flat Glass Industry,Manufacturing Flat Glass Float Glass Process,Coating Glass Chemical Vapour Deposition,Examples of commercial glazing coatings prepared by CVD,73,SummaryScale of the Global Fla,Recommended Reading,D.W. Sheel and M.E. Pemble,Atmospheric Pressure CVD Coatings on Glass,ICCG4 2019,cvdtechnologies.co.uk/CVD%20on%20Glass.pdf,M.L. Hitchman, K.F. Jensen,Chemical Vapor Deposition,Academic Press, 1993,W.S. Rees,CVD of Non-metals, VCH, Weinheim, 2019,M. Ohring,The Materials Science of Thin Films,Academic Press, 2019,pilkington,74,Recommended ReadingD.W. Sheel,First in Glass,75,First in Glass75,谢谢你的阅读,知识就是财富,丰富你的人生,谢谢你的阅读知识就是财富,