Designing molecular precursors for inorganic nanomaterials

SSCI-VIDE+CDFA+SMRInternational audienceIndustrial development of chemical solution and vapor routes such as Sol-gel, MOD or MOCVD methods to inorganic nanomaterials is strongly dependent on the molecular engineering that involves design of tunable metal-organic precursors. These molecular precursors are usually the starting point of the processes and influence the micro- & nano-structure and, therefore, the nature and the properties of the obtained materials.1 The use of well-defined precursors also allows to establish relationships between the precursors and the final material and, therefore, to get some insight in to their transformation. This presentation will address different concepts of the ‘bottom-up’ approach with a special emphasis on the design of homo or heterometallic (‘single-source’) precursors which have (i) a formulation that matches well with that of the final materials, particularly stoichiometry between metals for multimetallic materials, (ii) appropriate physicochemical properties (solubility, thermal stability, volatility…), (iii) the required chemical functionalities (coordination sphere with an appropriate set of ligands), and (iv) a clean, low temperature conversion into materials with minimized undesired residues in the end.2,3 Catalytic applications of the obtained nanomaterials, especially in the field of photocatalysis, will be described. Keywords: molecular precursor, nanomaterials, Sol-Gel, metal-organic decomposition, metal oxide, metal selenide nanoparticles, metal fluoride composites, photocatalysisREFERENCES [1] S. Mishra, S. Daniele, Metal-organic derivatives with fluorinated ligands as precursors for inorganic nanomaterials, Chem. Rev. 2015, 115, 8379-8448.[2] a) S. Mishra, F. Morfin, V. Mendez, P. N. Swamy, J.-L. Rousset, S. Daniele, Nanometric NaYF4 as an unconventional support for Gold catalysts for oxidation reactions, ACS Omega, 2019, 4, 5852−5861; b) S. Mishra, E. Jeanneau, S. Mangematin, H. Chermette, M. Poor Kalhor, G. Bonnefont, G. Fantozzi, S. Le Floch, S. Pailhese, S. Daniele, A convenient and quantitative route to Sn(IV)–M [M = Ti(IV), Nb(V), Ta(V)] heterobimetallic precursors for dense mixed-metal oxide ceramics, Dalton Trans., 2015, 44, 6848–6862; c) Y. Chen, S. Mishra, G. Ledoux, E. Jeanneau, M. Daniel, J. Zhang, S. Daniele, Direct synthesis of hexagonal NaGdF4 nanocrystals from a single-source precursor: Upconverting NaGdF4:Yb3+,Tm3+ and its composites with TiO2 for near-IR-driven photocatalysis. Chem. Asian J., 2014, 9, 2415‒2421.[3] a) S. Gahlot, E. Jeanneau, F. Dappozze, C. Guillard, S. Mishra, Precursor-mediated synthesis of Cu2-xSe nanoparticles and its composites with TiO2 for improved photocatalysis, Dalton Trans. 2018, 47, 8897–8905; b) S. Mishra, D. Du, E. Jeanneau, F. Dappozze, C. Guillard, J. Zhang, S. Daniele, A facile molecular precursor-based synthesis of Ag2Se nanoparticles and its composites with TiO2 for enhanced photocatalytic activity, Chem. Asian J. 2016, 11, 1658-1663