Synthesis process control of low-thermal-expansion Fe2W3O12 by suppressing the intermediate phase Fe2WO6

The investigation reports in Fe2W3O12 are few due to the synthesis difficulty of pure phase Fe2W3O12. In the paper, rapid synthesis of pure phase Fe2W3O12 is developed using solid state sintering method with Fe2O3 and WO3 as raw materials and the addition of MoO3. The intermediate phase Fe2WO6 is easy to form by sintering Fe2O3 and WO3 with the content of addition MoO3 less than 3 mol%. Only after the content of addition MoO3 reaches 5 mol%, the Fe2W3O12 could form easily, even the temperature lower to 1000 degrees C. It is considered that addition MoO3 plays as a catalyst-stabilizer in the formation of Fe2W3O12. The as-synthesized Fe2W3O12 shows low thermal expansion (1.35 x 10(-6) degrees C-1) from 445 to 600 degrees C.