Photoreduction of nitrite to ammonia by metal phthalocyanines-adsorbed membrane

Abstract

The metal phthalocyanines (MPCs)-adsorbed Nafion (Nf) membranes (Nf/MPCs) are prepared and used for the photocatalytic reduction of nitrite ion. The selective formation of NH₄OH is observed when the Nf/MPC membrane is dipped in nitrite ion solution and photolysed in the presence of sacrificial electron donor such as triethanolamine (TEA). The Nf/MPC membranes behave as p-type semiconductors. The photosensitized reaction mechanism of the photocatalytic reduction of NO₂ ^- to NH₄ ⁺ formation is explained by the reaction of the e^- _{c b} with nitrite ion and the hole (h⁺ _{v b}) with TEA.