Hydrothermal reaction of NaBiO₃·nH₂O with transition-metal (Co, Ni, Cu) salts

Abstract

Hydrothermal reactions of a hydrated sodium bismuth oxide, NaBiO₃·1.4H₂O were performed with transition-metal salts MCl₂, M(NO₃)₂ and MSO₄ (M: Co, Ni, Cu). The common identified products from nitrate and chloride solutions were (Bi,M)₂O₂(OH)NO₃ and (Bi,M)OCl, respectively and every product contained a small amount of unknown impurity phases. Various unknown phases also appeared in the products from the sulfate solutions, and no common crystalline phases were observed. During the course of these hydrothermal reactions, a new bismuth sulfate, BiOHSO₄ was found by using a H₂SO₄ solution, and its crystal structure was clarified by using single-crystal X-ray diffraction data. No photocatalytic activity for the phenol degradation of BiOHSO₄ was observed under ultraviolet and visible light irradiation.