A new sol-gel synthesis of Mn3O4 oxide and its electrochemical behavior in alkaline medium

Abstract

International audienceIn this investigation, Mn3O4 spinel-type oxide was synthesized at low temperature using the Pechini process. We employed a sol-gel route, in which a solution of Mn(II) in a mixture of citric acid and ethylene glycol was heated to form a polymeric precursor, followed by annealing at lower temperature. The oxide obtained was identified by X-ray diffraction, scanning electron spectroscopy, and Raman spectroscopy. The results revealed that the formation of Mn3O4 hausmannite structure with a minor secondary phase of MnSO4 occurred at or above 280 A degrees C. The sample powder consisted of fine grains with homogeneous morphology and an average size close to 1 mu m was obtained. This new preparation procedure yielded an electrode oxide which appears to be a promising cathode material for fuel cells and metal-air batteries

Pseudocapacitive Hausmannite Nanoparticles with (101) Facets: Synthesis, Characterization, and Charge‐Transfer Mechanism

“…[22,34,[41][42][43][44][45][46][47] Mn 3 O 4 octahedra with (111) [48] or (101) [39] facets have been synthesized; however, the sizes of these particles were approximately 100-200 nm. [22,34,[41][42][43][44][45][46][47] Mn 3 O 4 octahedra with (111) [48] or (101) [39] facets have been synthesized; however, the sizes of these particles were approximately 100-200 nm.…”

“…High-temperature calcinations and sol-gel methods are commonly used to synthesize Mn 3 O 4 materials, yielding micrometer-sized structures with an array of morphologies such as rods, wires, and particles. [22,34,[41][42][43][44][45][46][47] Mn 3 O 4 octahedra with (111) [48] or (101) [39] facets have been synthesized; however, the sizes of these particles were approximately 100-200 nm. A reliable room-temperature synthesis of faceted Mn 3 O 4 nano-octahedra (less than 20 nm) with a narrow size distribution and high percentages of certain low-index facets, such as (001) or (101), has only been reported in a limited number of cases.…”

Rapid synthesis of Mn3O4 powder from pyro-synthesis of ethylene glycol–metal nitrate precursor assisted by nitric acid

“…Peaks ascribed to as econdary phase weren ot detected, stronglysuggesting that the synthesized oxide was asingle phase of Mn 3 O 4 .T he average crystallite size, estimated through Eq. The bands centered at 844, 903 and 1346 cm -1 are attributed to the vibration of the O-Hbond combined with manganese atoms [3,21]. As can be seeninTable 1, the crystallite size obtained in this work lies among the lowest reported in the literature [29 -38] forMn 3 O 4 .…”

Metal oxide/hydroxide based materials for supercapacitors

“…Among these, Mn 3 O 4 with spinel structure is one of the most stable mixed oxides state. It is widely used as electrode material for supercapacitors [85], a cathode material for fuel cells/metal-air batteries [86] and anode material for lithium batteries [87]. It has high theoretical SC (1370 Fg −1 ) [88], abundance, low cost, and low toxicity.…”