A controlled synthesis of γ-MnOOH nanorods via a facile hydrothermal method for high-performance Li-ion batteries

Abstract

In this work, a hydrothermal reduction route was applied for the controlled production of MnOOH nanohydrangeas and MnOOH nanorods. The structure and morphology of formed products were characterized. Both MnOOH...

Synthesis and Electrochemical Properties of One‐Dimensional γ‐MnOOH Nanorods

“…The weak broad peak near 1400 cm −1 is the C−O stretching vibration peak, which can be attributed to the CO 3 2− stretching vibration and bending vibration absorption peaks. CO 3 2− may come from CO 2 in the air, which is adsorbed on the surface of the material with the pore structure [28] . The absorption peak at 1620 cm −1 is a deformation vibration of the O−H bond in the Mn−OH group.…”

“…CO 3 2À may come from CO 2 in the air, which is adsorbed on the surface of the material with the pore structure. [28] The absorption peak at 1620 cm À 1 is a deformation vibration of the OÀ H bond in the MnÀ OH group. The absorption peak at 2920 cm À 1 is the symmetric telescopic vibration peak of methylene, and the broad peak at 3430 cm À 1 is the telescopic vibration peak of À OH in the surface moisture of the material.…”

“…In recent years, manganese oxides have attracted much attention in the field of supercapacitors due to their advantages such as abundant resources, environmental friendliness, and high theoretical specific capacity [17–27] . MnOOH, as a trivalent hydroxide polycrystalline material stable at room temperature with easy preparation and flexible structure, as well as higher conductivity (10 −4 –10 −5 S/cm) compared to MnO 2 , is considered a promising candidate for supercapacitor electrode materials [28–31] …”

“…[17][18][19][20][21][22][23][24][25][26][27] MnOOH, as a trivalent hydroxide polycrystalline material stable at room temperature with easy preparation and flexible structure, as well as higher conductivity (10 À 4 -10 À 5 S/cm) compared to MnO 2 , is considered a promising candidate for supercapacitor electrode materials. [28][29][30][31] MnOOH has a structural unit based on [MnO 6 ] octahedra, which form tunneled or layered alkaline manganese oxide crystalline compounds by means of co-prisms or co-angles between these [MnO 6 ] octahedra. According to the different internal structures, MnOOH can be classified into α, β, and γ crystal types, and among these three crystalline types, γ-MnOOH has the most stable thermodynamic properties, showing a (1×1) tunneling structure with H atoms located in the tunnel.…”

The Synthesis of Manganese Hydroxide Nanowire Arrays for a High-Performance Zinc-Ion Battery

“…In such electrochemical systems, the typical chemical conversion reaction mechanism of the cathodic MnO 2 is one electron redox (Mn 4+ to Mn 3+ ) in the conventional natural aqueous electrolyte: MnO 2 + H + + e − ↔ MnOOH [ 29 ]. Inspired by this equation, Zhang et al synthesized γ-MnOOH nanorods that possess an enhanced electrochemical performance with a specific capacity of 965 mA h g −1 at a current density of 200 mA g −1 for lithium-ion batteries [ 30 ]. As a layered material, manganese hydroxide possesses a large interlayer spacing, which provides a rapid transport pathway for efficient Zn 2+ insertion/extraction.…”