Spray‐combustion synthesis of indium tin oxide nanopowder

Abstract

Nanocrystalline indium tin oxide (ITO) powders were prepared by a novel spray combustion method. Using single-drop study equipment, we studied the thermodynamics of the combustion reaction. The reaction can be ignited at air temperature as lower as 171.3°C when using urea and glucose as composite fuel. Once the reaction is ignited, the combustion temperature can surge to above 500°C, generating nanocrystalline ITO powders with grain size about 40 nm. Footages from high-speed camera demonstrated that the reaction is in three-step: moderate beginning, violent middle, and decaying end. It is also noticed that the ignition is very sensitive to the air temperature, even 0.2°C minus deviation may fail the combustion. The combustion reaction is self-sustainable, which saves the energy supply. And the low ignition temperature means the combustion reaction can be carried out in a conventional spray dryer. Our results provide a feasible way to mass production of nanocrystalline ITO powders, which as a methodology, may be extended to the production of other oxide nanopowders.

Powder Metallurgy Route to Ultrafine‐Grained Refractory Metals

“…However, for nanopowders, surface diffusion‐enabled particle coarsening and repacking can contribute to early‐stage sintering at very low temperatures. [ 92,93 ] Coarsening of the nanopowders relative to the pore size could cause concurrent repacking and result in a higher packing factor, thus densification via surface diffusion only, and this mechanism could work even at low densities and for the pores larger than the critical size of the thermodynamically sinterable pores. Meanwhile, coarsening of the nanopowders also reduces the coordination number of the pore and changes the balance of pore surface tension, resulting in further densification via grain boundary diffusion.…”

Morphological evolution driven semiconducting nanostructures for emerging solar, biological and nanogenerator applications

“…The combustion method is emerging as a facile and economically viable technique, and was successfully used in the preparation of a large number of technologically useful oxides and nanomaterials. 78–88 In addition to these novel synthesis methods, mixed strategies including physical and chemical routes are used to fabricate different nanomaterials. Currently, the hybrid synthesis is a popular approach to achieve the desired nanostructures through both chemical and physical efforts.…”

“…The combustion method is emerging as a facile and economically viable technique, and was successfully used in the preparation of a large number of technologically useful oxides and nanomaterials. [78][79][80][81][82][83][84][85][86][87][88] In addition to these novel synthesis methods, mixed strategies including physical and chemical routes are used to fabricate different nanomaterials. Currently, the hybrid synthesis is a popular approach to achieve the desired nanostructures through both chemical and physical efforts.…”

Fabrication of Custom-Designed and Cost-Effective Spin-Spray Pyrolysis Unit

“…The diameter of the spray drops depends on the size of the nozzle head, the surface tension of the precursor solution, its viscosity and the pressure difference before and after the spraying. Alternatively, ultrafine dispersive powders [20] could be produced by the swift rise of the temperature inside the chamber. The rotation enables uniform film deposition throughout the area.…”