Novel morphology of needle-Like nanoparticles of Na2Mo2O7 synthesized by using Ultrasonic spray pyrolysis

Ivana Lj Validžić,Miodrag Mitrić

doi:10.1590/s1516-14392012005000142

Abstract

Low-temperature method for the synthesis of novel morphology of needle-like nanoparticles of disodium dimolybdate (Na2Mo2O7) in the process of ultrasonic spray pyrolysis (USP) using aqueous solutions of thermodynamically stable molybdenum (VI) oxide clusters as precursor is described. Needle-like Na2Mo2O7 particles were obtained and collected in toluene, while centrifugation was employed to isolate solid material from solution. The scanning electron microscopy (SEM) confirmed that the morphology of the synthesized Na2Mo2O7 particles is needle-like collected into bundles. The X-ray Powder Diffraction (XRPD) analysis revealed appearance of orthorhombic Na2Mo2O7, synthesized at 300 °C. By comparing the XRPD pattern of the synthesized needle-like Na2Mo2O7 powder obtained in the process of USP with the XRPD pattern simulated for randomly-distributed crystallites by planes, the most prefered growth plane of needle-like nanoparticles were found.

Highlights

Ternary molybdates generally (Na–Mo–O) have attracted considerable attention because of their interesting structural and thermodynamic properties[1]
We report the low-temperature synthesis in the process of ultrasonic spray pyrolysis (USP) using molybdenum (VI) oxide clusters as a precursor
The Na2Mo2O7 powders were obtained in the process of ultrasonic spray pyrolysis (USP) using solutions consisting of molybdenum (VI) oxide clusters as a starting material

Summary

Introduction

Ternary molybdates generally (Na–Mo–O) have attracted considerable attention because of their interesting structural and thermodynamic properties[1]. Molybdate compounds have been extensively studied for solid-state lighting with light emitting diodes. In most cases, this structure is luminescent ion hosts in order to obtain a well defined emission property[3,4]. Conventional method for preparation of disodium dimolybdate (Na2Mo2O7) is thermal treatment of mixture consisting of sodium molybdate and molybdenum trioxide in a platinum crucible for two weeks at 700 °C11. A new low‐temperature method has been reported for the synthesis of Na2Mo2O7 in the process of USP using acidified aqueous solutions of thermodynamically stable molybdenum (VI). The. In this paper, we report the low-temperature synthesis in the process of USP using molybdenum (VI) oxide clusters as a precursor. Drastic variation in the morphology as well as in the structure preferential orientation were found only by changing the solvent polarity

Experimental Procedures

Results and Discussion

Summary