Layered Graphitic Carbon Host Formation during Liquid-free Solid State Growth of Metal Pyrophosphates

Abstract

Original citationDiaz, C., Valenzuela, M. L., Lavayen, V. and O'Dwyer, C. (2012) 'Layered graphitic carbon host formation during liquid-free solid state growth of metal pyrophosphates', Inorganic Chemistry, 51 (11) AbstractWe report a successful ligand-and liquid-free solid state route to form metal pyrophosphates within a graphitic carbon matrix through a single step approach involving pyrolysis of previously synthesized organometallic derivatives of a cyclotriphosphazene. In this case, we show how single crystal Mn 2 P 2 O 7 can be formed either on the micro-or nanoscale in the complete absence of solvents or solutions by an efficient combustion process using rationally designed macromolecular trimer precursors, and present evidence and a mechanism for layered graphite host formation.Using in situ Raman spectroscopy, infrared spectroscopy, X-ray diffraction, high resolution electron microscopy, thermogravimetric and differential scanning calorimetric analysis, and near-edge X-ray absorption fine structure examination, we show evidence for the formation of a layered, graphitic carbon in the matrix and how the process occurs. The identification of thermally and electrically conductive graphitic carbon host formation is important for the further development of this general ligandfree synthetic approach for inorganic nanocrystal growth in the solid state, and can be extended to form a range of transition metals pyrophosphates. For important energy storage applications, the method gives the ability to form oxide and (pyro)phosphates within a conductive, intercalation possible, graphitic carbon as host-guest composites directly on substrates for high rate Li-ion battery and emerging alternative positive electrode materials.

Synthesis and magnetic properties of nanostructured metallic Co, Mn and Ni oxide materials obtained from solid-state metal-macromolecular complex precursors

“…(ii) The organic matter between the metal centers is removed as CO 2 and H 2 O aer the pyrolysis process, creating holes which nucleate the metal centers, subsequently forming nanoparticles. 20 (iii) At intermediate temperatures of the pyrolysis process, a graphite surface is formed from the organic polymer which acts as a solid-state template where the nanoparticles begin to grow. 20 (iv) By comparison, pyrolysis of the metallic salts without the polymer present usually yields big agglomerated particles.…”

“…20 (iii) At intermediate temperatures of the pyrolysis process, a graphite surface is formed from the organic polymer which acts as a solid-state template where the nanoparticles begin to grow. 20 (iv) By comparison, pyrolysis of the metallic salts without the polymer present usually yields big agglomerated particles. 21,22 In this paper, we present the preparation of Mn 2 O 3 , Co 2 O 3 and NiO nanoparticles from coordination metal-polymer complexes which grow over graphite.…”

Bimetallic Au/Ag Metal Superstructures From Macromolecular Metal Complexes in Solid-State

“…The first step involves the cross-linking 13 of the polymer induced by the coordination by the PSP-co-4-PVP or Chitosan polymer chains to the metal centers during the initial annealing step, followed by the carbonization of the organic matter to produce holes were the metal centers begin to coarsen and grow 43 . Carbonization of the organic matter usually occurs during pyrolysis of metallic and organometallic derivatives of polymers around 350 °C 43 .…”

“…Carbonization of the organic matter usually occurs during pyrolysis of metallic and organometallic derivatives of polymers around 350 °C 43 . Some incomplete combustion always produces some CO 44 which reduces the metallic Au(I) and Ag(I) salts to Au and Ag which bind together.…”

Solution, Solid-State Two Step Synthesis and Optical Properties of ZnO and SnO2 Nanoparticles and Their Nanocomposites with SiO2

“…We have previously reported two solid-state methods allowing the synthesis of different metallic nanostructured materials (M, M x O y , and M x P y O z ) for a range of transition, valve and noble metals. The first methodology employed organometallic derivatives directly linked to poly-and cyclotriphosphazenes as molecular precursors of the metallic nanostructure, [14][15][16][17] while the second used solid-state mixtures of an appropriate organometallic moiety and cyclotriphosphazenes not possesing any coordinative functional group (i.e. cyclospirophosphazenes of general formula [N=P(O 2 C 12 H 8 )] 3 ).…”