J. Technology and Education, Vol.21, No.2, pp.39-43 (2014)

研究論文

 

過マンガン酸塩溶液への超音波照射による二酸化マンガンの合成

 

宮本　信明^＊，横尾　恭央

 

有明工業高等専門学校物質工学科（〒836-8585 大牟田市東萩尾町150番地）

miyamoto@ariake-nct.ac.jp

 

Synthesis of Manganese Dioxide by Ultrasonic Irradiation

in a Permanganate Solution

 

Nobuaki MIYAMOTO^*,  and Yasuo YOKOO

 

　 Department of Chemical Science and Engineering, Ariake National College of Technology

（150, Higashihagio-machi，Omuta，Fukuoka  836-8585, Japan）

 

(Received May 22, 2014; Accepted July 2, 2014)

 

Abstract

A colloidal manganese dioxide was prepared by reducing a permanganate solution with thiosulfate. This product was also obtained by ultrasonic irradiation in a permanganate solution, without a reducer, to form hydrogen peroxide from water. The formation of the α-MnO₂ phase by the colloidal process was confirmed by X-ray diffraction after heating at 375˚C for 3h in air. The powders were in a range of 200–600 nm, and the specific surface areas were 108–140 m² g^-1, increasing with ultrasonic irradiation. The Mn (IV) content of the products (78–83%) was lower than that of electrolytic manganese dioxide (EMD, 93%). The discharge capacities of the products obtained by ultrasonic irradiation were higher than that of the product without ultrasonic irradiation and that of EMD. The performance of manganese dioxide as a cathode material for a lithium-manganese dioxide cell has been improved by ultrasonic irradiation of the reaction solution.

 

Key Words : Ultrasonic Irradiation, Permanganate Solution, Manganese Dioxide, Battery Capability