Self-healing for nanolayered manganese oxides in the presence of cerium(iv) ammonium nitrate: new findings†
Abstract
The self-healing reactions for metal oxides are among the most important reactions. For Mn oxides in the presence of cerium(IV) ammonium nitrate, Mn(II) and MnO4− combine and heal the Mn oxide. In the reaction, Mn(II) is formed from the reductive dissolution of the Mn oxide or by disproportionation of Mn(III) on the surface of the oxide. This Mn(II) is then oxidized by cerium(IV) ammonium nitrate to MnO4−. The MnO4− in the presence of Mn oxide oxidizes water or in a second pathway is reduced by Mn(II) to form Mn oxide. Here, we use the multivariate curve resolution-alternative least squares method for the first time to analyze spectroscopic data and obtain concentration profiles of cerium(IV) ammonium nitrate and MnO4− during the reaction under different conditions.