Nanočástice PS 2012 1 Syntéza Nps – Brno, PS 2012 Přednášející: doc. Jiří Sopoušek E-mail: sopousek@mail.muni.cz, tel.: 549497138 Ofice: UKB A12/M231 Ústav chemie: http://ustavchemie.sci.muni.cz/ Audio test: Start Au-nano • chemické metody přípravy II Nanočástice PS 2012 Coprecipitation • Sol-gel Processing • Microemulsions • Hydrothermal/Solvothermal Synthesis • Microwave Synthesis • Sonochemical Synthesis • Template Synthesis • Biomimetic Synthesis Nanočástice PS 2012 Precipitační syntézy NPs Analogie srážecích reakcí Problémy: nekontrolovaná velikost, krystaly,… Používá se zřídka Nanočástice PS 2012 Example: Precipitation of ZnS nanoparticles from a solution containing thioacetamide and zinc acetate Thioacetamide is used as a sulfide source. Zn2+ + S2-  ZnS Murray C.B. et al., Annu. Rev. Mater. Sci. 2000, 30, 545. Nanočástice PS 2012 Solvotermální syntéza Precursory se rozpustí v horkém rozpouštědle (např. n-butyl alcohol) v autoklávu. Nevodná rozpouštědla zabezpečují meně drastické a selekticnější reakční prostředí. Je-li rozpouštědlem voda pak se proces nazývá hydrotermální syntéza. Precursor: Titanium n-butoxide Example: TiO2 Nanocrystallites Precursor solution with butyl alcohol Hlavně pro přípravu oxidů Nanočástice PS 2012 Yu, J. C. et al. J. Solid State Chem. 2005, 178, 321; Cryst. Growth Des. 2007, 7, 1444 Příklad: Solvotermální synthéza ZnIn2S4 ZnIn2S4 microspheres prepared by an oleylamine-assisted solvothermal method. Procedure, 1 g of oleylamine and 0.03 mmol of Zn(AC)2 were firstly dissolved in 24 mL tetrahydrofuran (THF) at room temperature to obtain a homogenous solution by vigorous magnetic stirring for 0.5 h, and then 0.06 mmol of InCl3 and 0.5 ml of CS2 were added under magnetic stirred. The mixed solution was then transferred into a 30 mL Teflon-lined autoclave, and kept at 180 °C for 24 h. After the autoclave was cooled to room temperature naturally, a yellow precipitate was obtained, then it was filtered and washed with absolute ethanol and distilled water for several times. Finally ZnIn2S4 was obtained after drying in vacuum at 60 °C. Aplikace fotokatalýza http://www.sciencedirect.com/science/article/pii/S036031991201840X Nanočástice PS 2012 Hydrotermální syntéza Oxidů Iron oxides ze solí Fe: Step 1: The pH is increased up to 10-14 by adding ammonium bases, (N(CH3)4-OH), (N(C2H5)4-OH) or (N(C3H7)4-OH). Step 2: The nanoparticles are then submitted to a hydrothermal treatment between 150 and 250°C. Hydrothermal Synthesis of Monodisperse Magnetite Nanoparticles. Daou, T. J.; Pourroy, G.; Begin-Colin, S.; Greneche, J. M.; UlhaqBouillet, C.; Legare, P.; Bernhardt, P.; Leuvrey, C.; Rogez, G. Chemistry of Materials (2006), 18(18), 4399-4404. K oxidaci stačí kyslík rozpuštěný ve vodě Nanočástice PS 2012 Kontinuální hydrotermální syntéza Oxidů http://www.google.cz/imgres?q=hydrothermal+synthesis+nanoparticle&um=1&hl=cs&sa=N&tbo=d&biw=1344&bih=673&tbm=isch&tbnid= L05Nc5QomOdv8M:&imgrefurl=http://www.suflux.com/EN/prod/supercritical-hydrothermal- synthesis.html&docid=Sa_ZvaupHCgmkM&imgurl=http://www.suflux.com/EN/prod/img/supercritical-hydrothermal- synthesis_img003.gif&w=580&h=400&ei=O5CzULhTjM3hBL25gdAN&zoom=1&iact=hc&vpx=1031&vpy=373&dur=3726&hovh=186&hov w=270&tx=141&ty=98&sig=107486980385906603851&page=3&tbnh=134&tbnw=195&start=52&ndsp=35&ved=1t:429,r:64,s:0,i:281 Supercritical Hydrothermal Synthesis LiCoO2, LiMnO2, CeO2, CuO, ZnP, TiO2, BaFe12O19, NixZn1-xFe2O4 Nanočástice PS 2012 Zno nanoparticles obtained by hydrothermal synthesis using microwave heating http://www.faqs.org/patents/app/2011022335 9 Hydrotermální syntéza ZnO Formation of ZnO nanoparticles using a fast continuous flow hydrothermal synthesis method. The synthesis conditions have been varied with respect to temperature, pH, and concentration of the Zn(NO3)2•4H2O + NaOH aqueous precursor. The different conditions affect the size, morphology, and crystallinity of the produced ZnO nanoparticles… Nanočástice PS 2012 Patent: HYDROTHERMAL SYNTHESIS OF LiFePO4 @ C NANOPARTICLES (Li-články) Claims: 1. A method of forming a film on a substrate, ……………..za použití metody ..za vzniku …filmu lithium containing nanocrystals na substrátu. 2. Prekurzory………… LiH2PO4, LiOH, LiNO3, LiCH3COO, LiCl, Li2SO4, Li3PO4, Li(C5H8O2), and combinations thereof. 3. Rozpouštědla………. : water, diethylene glycol, ethylene glycol, dimethyl sulfoxide (DMSO), polyethylene glycol (PEG), and combinations thereof. Example 1 [0053] LiFePO4 nanoparticles were formed via hydrothermal synthesis as follows. A lithium source (LiOH), a phosphate source ((NH4)2HPO4), an iron source (Fe(CH3COO)2), and a carbon source (glucose) were combined to form a deposition mixture. The LiFePO4 may be formed according to the following reaction: LiOH+(NH4)2HPO4+Fe(CH3COO)2LiFePO4+2CH.sub- .3COOH↑ [0054] The deposition mixture was exposed to ultrasonic energy at an energy level of 250 kHz. The deposition mixture was exposed to microwave irradiation for 15 minutes at 230° C. to form carbon coated LiFePO4 via a hydrothermal carbonization reaction. The carbon coated LiFePO4 was subsequently exposed to ultrasonic energy at an energy level of 300 kHz to reduce agglomeration. The carbon coated LiFePO4 was deposited on an aluminum substrate via a thermal spray process at 700° C. to form a LiFePO4/C nanocomposite film comprising lithium containing nanocrystals. http://www.faqs.org/patents/app/20110223359#ixzz2DL6kwc4r http://diit.cz/clanek/lifepo4-akumulatorovy- zazrak-miri-i-do-tuzkovych-baterek Nanočástice PS 2012 Sol-gel syntéza • Formation of stable sol solution • Gelation via a polycondensation or polyesterification reaction • Gel aging into a solid mass. causes contraction of the gel network, also (i) phase transformations and (ii) Ostwald ripening. • Drying of the gel to remove liquid phases. Can lead to fundamental changes in the structure of the gel. • Dehydration at temperatures as high as 8000 oC, used to remove M-OH groups for stabilizing the gel, i.e., to protect it from rehydration. • Densification and decomposition of the gels at high temperatures (T > 8000 oC), i.e., to collapse the pores in the gel network and to drive out remaining organic contaminants Nanočástice PS 2012 Alkoxide +H2O Stabilizer Nanodisperse Oxide Sol (Particulate or Polymeric) -H2O Gel Xerogel Porous TiO2 -H2O T > 400 ºC -H2O -Stabilizer Example: TiO2 nanoparticle-mediated mesoporous film by sol-gel processing TiO2 nanoparticle-mediated mesoporous film (Yu, J. C. et al. Chem. Mater. 2004, 16, 1523.) Nanočástice PS 2012 Microwaves are a form of electromagnetic energy with frequencies in the range of 300 MHz to 300 GHz. The commonly used frequency is 2.45G Hz. Interactions between materials and microwaves are based on two specific mechanisms: dipole interactions and ionic conduction. Both mechanisms require effective coupling between components of the target material and the rapidly oscillating electrical field of the microwaves. Syntéza za pomoci mikrovlnného ohřevuol-gel syntéza Nanočástice PS 2012 Conventional Heating by Conduction • conductive heat • heating by convection currents • slow and energy inefficient process The temperature on the outside surface is in excess of the boiling point of liquid Nanočástice PS 2012 Heating by Microwave Irradiation inverted temperature gradients ! • Solvent/reagent absorbs MW energy • Vessel wall transparent to MW • Direct in-core heating • Instant on-off Nanočástice PS 2012 Microwave (MW) rapid heating has received considerable attention as a new promising method for the one-pot synthesis of metallic nanostructures in solutions. In this concept, advantageous application of this method has been demonstrated by using some typical examples for the preparation of Ag, Au, Pt, and AuPd nanostructures. Not only spherical nanoparticles, but also single crystalline polygonal plates, sheets, rods, wires, tubes, and dendrites were prepared within a few minutes under MW heating. Morphologies and sizes of nanostructures could be controlled by changing various experimental parameters, such as the concentration of metallic salt and surfactant polymer, the chain length of the surfactant polymer, the solvent, and the reaction temperature. In general, nanostructures with smaller sizes, narrower size distributions, and a higher degree of crystallization were obtained under MW heating than those in conventional oil- Nanočástice PS 2012 Example: Microwave-assisted synthesis of ZnO nanoparticles OH2 Zn H2O OAc OAc O Zn O O O Zn O O O DEG Microwave ( ) Nucleation Aggregation ClusterNanocrystalCrystal structure Schematic representation and transmission electron microscope (TEM) images of ZnO-cluster nanoparticles prepared by microwave irradiation Yu, J. C. et at., Adv. Mater. 2008, in press. Sonochemická příprava NPs Nanočástice PS 2012 18 http://www.organic- chemistry.org/topics/sonochemi stry.shtm The use of ultrasound in chemical reactions in solution provides specific activation based on a physical phenomenon: acoustic cavitation. Cavitation is a process in which mechanical activation destroys the attractive forces of molecules in the liquid phase. Applying ultrasound, compression of the liquid is followed by rarefaction (expansion), in which a sudden pressure drop forms small, oscillating bubbles of gaseous substances. These bubbles expand with each cycle of the applied ultrasonic energy until they reach an unstable size; they can then collide and/or violently collapse. Nanočástice PS 2012 http://www.mdpi.com/2073- 4441/2/1/28 ZnO NPs luminiscent Příprava NPs: Oxidy (ZnO, CuO, …) Problém: kontaminace materiálem sonifikačního prstu (W, Ti) Nanočástice PS 2012 Examples: sonochemical synthesis of mesoporous TiO2 particles Mesoporous TiO2 20 kHz sonochemical processor Nanočástice PS 2012 Porézní CuO http://nanotechweb.org/cws/article/lab/37301 Příklady NPs připravených sonochemicky Mikročástice ZnO (kontaminace Ti a W ). Syntéza na UCh , L. Pražák) Nanočástice PS 2012 Biomimetic Synthesis Vytváření nanočástic přirozenými pochody v přírodě Výhody: Biomimetic or bio-inspired processes generally occur under mild conditions such as room temperature, aqueous environment, and neutral pH, and thus are benign in comparison to traditional chemical reactions. Biologically inspired synthesis, hierarchical structuring, and stimuli-responsive materials chemistry may enable nanostructured materials systems with unprecedented functions . http://www.sciencedirect.com/science/article/pii/S 0001868612000954 Nanočástice PS 2012 A protein of methanococcus jannaschii MjHsp Protein-encapsulated CoPt nanoparticles by bio-inspired synthesis Examples: biomimetic synthesis Model for silver crystal formation by silver-binding peptides. biosynthetic silver nanoparticles. (Stone M. O. et al. Nat. Mater. 2002, 1, 169.) (Stone M. O. et al. Adv. Funct. Mater. 2005, 15, 1489.) Nanočástice PS 2012 Micelární příprava CdS http://www.nature.com/pj/journal/v43/n3/fig_tab/pj2010137s c1.html Nanočástice PS 2012 Coprecipitační syntézy NPs Magnetic nanoparticles of Ni0.5Co0.5Fe2O4 (size: 18 ± 3 nm) http://www.sciencedirect.com/science/article/p ii/S0254058412001605 Nanočástice PS 2012 http://www.sciencedirect.com/science/art icle/pii/S0009250910005142 Nanoparticlesynthesis in davkovacích microreactorech Nanočástice PS 2012 http://blogs.rsc.org/ce/2011/01/05/hot-article-using-supercritical-water-to- make-ceria-nanoparticles/ HOT Article: Using supercritical water to make hybrid ceria nanoparticles Příprava NPs za superkrytických podmínek Nanočástice PS 2012 28 Diskuse ? http://www.netl.doe.gov/newsroom/labnotes /2011/04-2011.html Unconventional Oil and Gas Nanočástice PS 2012 Volné presentace pro syntézu ke stažení: http://freedownloadb.com/pdf/nanoparticle- synthesis-methods-ppt http://ebookbrowse.com/sy/synthesis-of- nanoparticles