Direct and continuous synthesis of VO2 nanoparticles.

Monoclinic VO2 nanoparticles are of interest due to the material's thermochromic properties, however, direct synthesis routes to VO2 nanoparticles are often inaccessible due to the high synthesis temperatures or long reaction times required. Herein, we present a two-step synthesis route for the preparation of monoclinic VO2 nanoparticles using Continuous Hydrothermal Flow Synthesis (CHFS) followed by a short post heat treatment step. A range of particle sizes, dependent on synthesis conditions, were produced from 50 to 200 nm by varying reaction temperatures and the residence times in the process. The nanoparticles were characterised by powder X-ray diffraction, Raman and UV/Vis spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The nanoparticles were highly crystalline with rod and sphere-like morphologies present in TEM micrographs, with the size of both the rod and spherical particles being highly dependent on both reaction temperature and residence time. SEM micrographs showed the surface of the powders produced from the CHFS process to be highly uniform. The samples were given a short post synthesis heat treatment to ensure that they were phase pure monoclinic VO2, which led to them exhibiting a large and reversible switch in optical properties (at near-IR wavelengths), which suggests that if such materials can be incorporated into coatings or in composites, they could be used for fenestration in architectural applications.

[1]  Christopher J. Tighe,et al.  Scale Up Production of Nanoparticles: Continuous Supercritical Water Synthesis of Ce–Zn Oxides , 2013 .

[2]  Yi Ding,et al.  Nanoscale Magnesium Hydroxide and Magnesium Oxide Powders: Control over Size, Shape, and Structure via Hydrothermal Synthesis , 2001 .

[3]  Antoine Guisan,et al.  Biodiversity: Predictive traits to the rescue , 2014 .

[4]  K. Arai,et al.  Hydrothermal synthesis of zirconia nanocrystals in supercritical water , 2004 .

[5]  Xiaonan Chen,et al.  Voltage-Triggered Ultrafast Phase Transition in Vanadium Dioxide Switches , 2013, IEEE Electron Device Letters.

[6]  Volker Eyert,et al.  The vanadium Magnéli phases V n O 2 n − 1 , 2004 .

[7]  F. Sediri,et al.  From V2O5 foam to VO2(B) nanoneedles , 2006 .

[8]  Ivan P. Parkin,et al.  Atmospheric pressure chemical vapour deposition of thermochromic tungsten doped vanadium dioxide thin films for use in architectural glazing , 2009 .

[9]  P. Schilbe,et al.  Lattice dynamics in VO2 near the metal-insulator transition , 2004 .

[10]  T. Arita,et al.  Surfactant-Assisted Hydrothermal Synthesis of Water-Dispersible Hafnium Oxide Nanoparticles in Highly Alkaline Media , 2012 .

[11]  P. Jin,et al.  Synthesis and characterization of plate-like VO2(M)@SiO2 nanoparticles and their application to smart window , 2013 .

[12]  Claes-Göran Granqvist,et al.  Nanothermochromics: Calculations for VO2 nanoparticles in dielectric hosts show much improved luminous transmittance and solar energy transmittance modulation , 2010 .

[13]  Joyeeta Nag,et al.  Synthesis of vanadium dioxide thin films and nanoparticles , 2008 .

[14]  V. Eyert,et al.  The vanadium Magnli phases VnO2n-1 , 2004, cond-mat/0403689.

[15]  C. Granqvist.  Transparent conductors as solar energy materials: A panoramic review , 2007 .

[16]  G. Stucky,et al.  VO2(B) nanorods: solvothermal preparation, electrical properties, and conversion to rutile VO2 and V2O3 , 2009 .

[17]  日本化学会.  Bulletin of the Chemical Society of Japan , 2022 .

[18]  T. Takada,et al.  Phase Transition and Electrical Properties of VO2 (A) , 1989 .

[19]  S. Zaman,et al.  Influence of pH, precursor concentration, growth time, and temperature on the morphology of ZnO nanostructures grown by the hydrothermal method , 2011 .

[20]  L. Mai,et al.  Electrical property of Mo-doped VO2 nanowire array film by melting-quenching sol-gel method. , 2006, The journal of physical chemistry. B.

[21]  M. Rajamathi,et al.  N-doped graphene-VO2(B) nanosheet-built 3D flower hybrid for lithium ion battery. , 2013, ACS applied materials & interfaces.

[22]  Yong Ding,et al.  Phase and shape controlled VO2 nanostructures by antimony doping , 2012 .

[23]  Wanxia Huang,et al.  Synthesis and properties of Mo and W ions co-doped porous nano-structured VO2 films by sol–gel process , 2012, Journal of Sol-Gel Science and Technology.

[24]  Gunnar A. Niklasson,et al.  Thermochromic VO2 Films for Energy-Efficient Windows , 1987, Optics & Photonics.

[25]  A. Magnéli,et al.  On the MoO2 Structure Type. , 1955 .

[26]  S. Wolf,et al.  Ferromagnetism in Rutile Structure Cr Doped VO2 Thin Films Prepared by Reactive-Bias Target Ion Beam Deposition , 2008 .

[27]  P. Schilbe.  Raman scattering in VO2 , 2002 .

[28]  P. Casey,et al.  Production of VO2 M1 and M2 nanoparticles and composites and the influence of the substrate on the structural phase transition. , 2009, ACS applied materials & interfaces.

[29]  Claes-Göran Granqvist,et al.  Nanothermochromics with VO2-based core-shell structures: Calculated luminous and solar optical properties , 2011 .

[30]  Yunlong Zhao,et al.  Nanoscroll Buffered Hybrid Nanostructural VO2 (B) Cathodes for High‐Rate and Long‐Life Lithium Storage , 2013, Advanced materials.

[31]  D. W. Sheel,et al.  Intelligent window coatings: atmospheric pressure chemical vapour deposition of vanadium oxides , 2002 .

[32]  L. Miao,et al.  Sol–gel template synthesis and characterization of VO2 nanotube arrays , 2012, Journal of Sol-Gel Science and Technology.

[33]  J. Darr,et al.  Optical and photocatalytic behaviours of nanoparticles in the Ti–Zn–O binary system , 2014 .

[34]  J. Dahn,et al.  Electrochemical Lithium Intercalation in VO 2 ( B ) in Aqueous Electrolytes , 1996 .

[35]  Xueliang Li,et al.  Hydrothermal synthesis and characterization of VO2 (B) nanorods array , 2007 .

[36]  W. Fan,et al.  Precursor Morphology Controlled Formation of Rutile VO2 Nanorods and Their Self-Assembled Structure , 2002 .

[37]  Zheng Hu,et al.  Preparation of VO2 nanowires and their electric characterization , 2005 .

[38]  Jawwad A. Darr,et al.  Direct Synthesis of Nanosized NiCo2O4 Spinel and Related Compounds via Continuous Hydrothermal Synthesis Methods , 2007 .

[39]  Younan Xia,et al.  Hydrothermal Synthesis of Monoclinic VO2 Micro- and Nanocrystals in One Step and Their Use in Fabricating Inverse Opals , 2010 .

[40]  A. Cheetham,et al.  Thermochromic VO2 nanorods and other vanadium oxides nanostructures , 2006 .

[41]  B. Dunn,et al.  Preparation of Nanotextured VO2[B] from Vanadium Oxide Aerogels , 2006 .

[42]  E. Baudrin,et al.  Synthesis and electroactivity of hydrated and monoclinic rutile-type nanosized VO2 , 2007 .

[43]  Liuming Yan,et al.  Mg-doped VO2 nanoparticles: hydrothermal synthesis, enhanced visible transmittance and decreased metal-insulator transition temperature. , 2013, Physical chemistry chemical physics : PCCP.

[44]  P Ekins,et al.  Evidence to Treasury Select Committee ‘Inquiry into Climate change and the Stern review: the implications for HM Treasury policy on tax and the environment’ , 2007 .

[45]  C. Patel,et al.  Simple Malonate and Maleate Complexes of Oxovanadium(IV) , 1967 .

[46]  Yadong Li,et al.  A CTAB-assisted hydrothermal orientation growth of ZnO nanorods , 2003 .

[47]  Kunio Arai,et al.  Rapid and Continuous Hydrothermal Crystallization of Metal Oxide Particles in Supercritical Water , 1992 .

[48]  C. Patel,et al.  Studies of Ammonium Dioxovanadium(V) Bisoxalate Dihydrate , 1964 .

[49]  I. Parkin,et al.  Vanadium(IV) oxide thin films on glass and silicon from the atmospheric pressure chemical vapour deposition reaction of VOCl3 and water , 2004 .

[50]  Christopher J. Tighe,et al.  Scaling-up a Confined Jet Reactor for the Continuous Hydrothermal Manufacture of Nanomaterials , 2013 .