Synthesis of MnO2 nanoparticles from sonochemical reduction of MnO4(-) in water under different pH conditions

Abulikemu Abulizi; Guo Hai Yang; Kenji Okitsu; Jun-Jie Zhu

doi:10.1016/j.ultsonch.2014.03.030

Synthesis of MnO2 nanoparticles from sonochemical reduction of MnO4(-) in water under different pH conditions

Ultrason Sonochem. 2014 Sep;21(5):1629-34. doi: 10.1016/j.ultsonch.2014.03.030. Epub 2014 Apr 13.

Authors

Abulikemu Abulizi¹, Guo Hai Yang², Kenji Okitsu³, Jun-Jie Zhu⁴

Affiliations

¹ Graduate School of Engineering, Osaka Prefecture University, Osaka 599-8531, Japan; State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, PR China; College of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046, PR China.
² State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, PR China.
³ Graduate School of Engineering, Osaka Prefecture University, Osaka 599-8531, Japan. Electronic address: okitsu@mtr.osakafu-u.ac.jp.
⁴ State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, PR China. Electronic address: jjzhu@nju.edu.cn.

PMID: 24793308
DOI: 10.1016/j.ultsonch.2014.03.030

Abstract

MnO2 was synthesized by sonochemical reduction of MnO4(-) in water under Ar atmosphere at 20°C, where the effects of solution pH on the reduction of MnO4(-) were investigated. The obtained XRD results showed that poor crystallinity δ-MnO2 was formed at pH 2.2, 6.0 and 9.3. When solution pH was increased from 2.2 to 9.3, the morphologies of δ-MnO2 changed from aggregated sheet-like or needle-like structures to spherical nanoparticles and finally to cubic or polyhedron nanoparticles. After further irradiation, MnO2 was readily reduced to Mn(2+). It was confirmed that H2O2 and H atoms formed in the sonolysis of water acted as reductants for both reduction for MnO4(-) to MnO2 and MnO2 to Mn(2+). The optimum irradiation time for the effective synthesis of MnO2 was 13 min at pH 2.2, 9 min at pH 6.0, 8 min at pH 9.3, respectively.

Keywords: Effect of pH; Manganese dioxide; Permanganate; Sonochemical reduction.

Publication types

Research Support, Non-U.S. Gov't