Low-temperature synthesis of Mn3O4 hollow-tetrakaidecahedrons and their application in electrochemical capacitors

Facile Synthesis of Porous Mn3O4 Nano­crystal–Graphene Nanocomposites for Electrochemical Supercapacitors

“…NaOH was the precipitant that leaded to the conversion of the Mn ion-GOto Mn(OH) 2 -GO. Because Mn(OH) 2 is a metastable compound that can be oxidized easily to Mn 3 O 4 by oxygen, [26,28] Mn 3 O 4 -GO composites will form. Hydrothermal treatment of the mixture resulted in the formation of the Mn 3 O 4 -graphene nanocomposites in a one step reaction.…”

“…[21] Generally, there are two ways to overcome this intrinsic drawback: one way is to design structures that can provide more electroactive sites to promote the electrochemical reaction, such as hollow structures, or those with well defined octahedra and polyhedra with enhanced capacitive behavior. [26][27][28] Another way is form a composite (or hybrid) of Mn 3 O 4 with other components to improve the electrode conductivity. In this case structural control (shape, size, and texture) is somewhat complicated, and involves elaborately adjusting the synthetic parameters and reaction kinetics.…”

Cage-like MnO 2 -Mn 2 O 3 hollow spheres with high specific capacitance and high rate capability as supercapacitor material

“…However, due to the low cell voltage of aqueous systems, their active material must reach higher values of both specific capacitance (F g -1 ) and rate performance (F g -1 at high current density A g -1 ) to be competitive 1 . Hollow-structured electrode materials improve these properties due to their large surface area, high porosity, and shell permeability [2][3][4] . Furthermore, different synthesis strategies have managed to achieve hollow spheres [5][6][7] , cubes 8 , polyhedrons 2 and bowls 9 , and their manipulation into double-layer shells 10,11 and multi-layer shells 12,13 .…”

“…Furthermore, different synthesis strategies have managed to achieve hollow spheres [5][6][7] , cubes 8 , polyhedrons 2 and bowls 9 , and their manipulation into double-layer shells 10,11 and multi-layer shells 12,13 . Hollownanostructured manganese oxides are attractive due to the high abundance, environmental friendliness and high theoretical specific capacity of manganese oxides 2,[14][15][16][17] . Various studies have reported hollow MnO2 structures such as spheres [14][15][16]18 , tubes 19 , urchin 20 , and paramecium 21 , prepared using methods employing oxidationetching and hard-templates.…”

Novel synthesis and formation process of uniform Mn2O3 cubes

“…Many efforts have been devoted to the synthesis of manganese-based materials with different morphologies. [12][13][14][15] Mn 2 O 3 is a traditionally attractive material for various industrial applications, such as a cheap and environmentally-friendly catalyst for removing carbon monoxide and nitrogen oxide from waste gas, [16][17][18] the precursor for producing soft magnetic materials, 19 and the electrode material of rechargeable lithium batteries. 20 Up to now, a wide variety of Mn 2 O 3 with different morphologies, ranging from one to three-dimensional structures, such as rods, wires, cubes, octahedra, and hollow spheres, have been synthesized through various methods.…”