Ultrafast Synthesis of Urchin-Like Rutile TiO₂ by Single-Step Microwave-Assisted Method.

Liqin Xiang,Chen Zheng,Yang Liu,Xiaopeng Zhao,Yuchi Liu

doi:10.3390/nano8080630

Abstract

The preparations of crystal titanium dioxide (TiO2) are often time-consuming multistep processes involving high temperature. Rapid and efficient methods to obtain TiO2 with anatase or rutile phase are desirable. In this paper, we describe an ultrafast single-step method to obtain urchin-like rutile TiO2 particles via microwave irradiation. In the procedure, TiCl4 aqueous solution was used as a reactant and toluene was used as a solvent. It takes only a few minutes without any further heat treatment. The samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and thermal gravimetric analysis (TGA). The effect of temperature, irradiation time and the ratio of precursor to solvent on the morphology and crystal structure were studied. The results show urchin-like rutile TiO2 with high stability is formed after only 5 min microwave irradiation at 135 °C.

Highlights

As one of most important semiconductors, titanium dioxide (TiO2) is very popular in many fields due to its outstanding properties [1,2,3]
The quartz tube with mixture was loaded into a mono-mode microwave synthesis system (CEM explorer)
The microwave system was operated at a frequency of 2.45 GHz and power of 150–250 W, the sample temperature was ramped to 135 ◦C with 20 ◦C/min and kept at the temperature for 1 to 30 min

Summary

Introduction

As one of most important semiconductors, titanium dioxide (TiO2) is very popular in many fields due to its outstanding properties [1,2,3]. Conventional methods including sol-gel, hydrothermal, and solvothermal processes are usually adopted to prepare TiO2 materials [15]. They generally involves several steps, long reaction time or high temperature to obtain crystalline TiO2 by conventional methods [15]. Hydrothermal or solvothermal methods are usually adopted to prepare urchin-like TiO2 particles. The electrochemistry method can reduce the reaction time of urchin-like TiO2, it still takes several tens of minutes [10]. We present a facile microwave-assisted solvothermal process to obtain the rutile TiO2 particles with urchin-like morphology in just a few minutes without any further heat treatment. The effect of temperature, irradiation time and the ratio of reactants to solvent on the morphology and the crystal structure of the TiO2 particles were investigated systematically

Synthesis

Characterization

Photocatalytic Measrement

Results and Discussion

Conclusions