Related Experiment Video
Updated: May 26, 2025
Characterization of Electrode Materials for Lithium Ion and Sodium Ion Batteries Using Synchrotron Radiation Techniques
Published on: November 11, 2013
Stabilizing Lattice Oxygen to Enable Durable MnO2 Electrocatalyst for Simultaneous Acidic Hydrogen Production and
Yingjie Song1,2, Jialong Qian1, Shengnan Li2
1State Key Laboratory of Chemical Resource Engineering, College of Chemistry, Beijing University of Chemical Technology, 100029, Beijing, China.
None:
Understanding and steering the stability of earth-abundant electrocatalysts in acidic medium is essential for proton exchange membrane (PEM) water electrolyzer. Manganese oxide (MnO2) is one of the promising candidates for acidic oxygen evolution reaction (OER), but it still suffers from the overoxidation and the underlying mechanism remains elusive. Here, we observed that lattice oxygen was involved in the OER process on γ-MnO2 via Mars-van-Krevelen mechanism. Combined with theoretical calculation, we revealed that the release of lattice oxygen lowers the energy barrier of Mn dissolution and compromises the electrode durability. Based on this finding, we propose a strategy to efficiently stabilize lattice oxygen and suppress Mn overoxidation by replacing OER with glucose oxidation to formic acid, which follows a Langmuir-Hinshelwood mechanism. As a result, the durability of γ-MnO2 was enhanced by 1100 times, enabling long stability up to 960 hours. Moreover, we demonstrated a production rate of 487.1 mmol h-1 for formic acid and 16.7 L h-1 for H2 at 40 A in a PEM electrolyzer, providing a sustainable and scalable route for converting water and biomass into valuable chemicals and fuels.
Related Concept Videos
01:09Complexation Equilibria: Factors Influencing Stability of Complexes
02:54Trends in Lattice Energy: Ion Size and Charge
02:54Lewis Structures of Molecular Compounds and Polyatomic Ions
02:16Resonance and Hybrid Structures
Resonance Structures and Resonance Hybrids
The Lewis structure of a nitrite anion (NO2−) may actually be drawn in two different ways, distinguished by the locations of the N–O and N=O bonds.
02:46Covalent Bonding and Lewis Structures
02:51Metal-Ligand Bonds
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...