Low-Temperature Green Synthesis of Multivalent Manganese Oxide Nanowires

Abstract

Manganese oxide nanomaterials hold promise for sustainable nanotechnologies given their utility for a variety of applications, the Earth's abundance of manganese, and their low toxicity relative to other nanomaterials. However green scalable synthesis methods for such nanomaterials are needed. We report here a green room-temperature synthesis of polycrystalline Mn 3 O 4 nanowires. In this procedure, aqueous Mn(II) is oxidized under circumneutral conditions by atmospheric oxygen in the presence of nanocrystalline iron oxide (α-Fe 2 O 3 ), an inexpensive catalyst, and a classic biochemical Good's buffer, PIPES (piperazine-N,N I -bis(2ethanesulfonic acid). The synthesis method is novel due to its simplicity, minimal energy input and waste output, and potential scalability. The Mn 3 O 4 nanowires have been characterized with a suite of electron microscopy techniques.

Hydrogen Reduction of Hematite Ore Fines to Magnetite Ore Fines at Low Temperatures

“…Step 3. During the above process, the reduction reaction extended continuously to the inner layer, and the entire hematite particle was completely reduced to magnetite [32]. Figure 11 shows the SEM images of samples reduced for 1 h and 2.5 h at 400 ∘ C as well as for 0.5 h and 2 h at 500 ∘ C.…”

“…Step 2. The new generation of Fe 2+ combined with Fe 2 O 3 , thereby producing Fe 3 O 4 through lattice reconstruction [31,32]:…”

Controllable Synthesis of Mn3O4 Nanowires and Application in the Treatment of Phenol at Room Temperature

“…Nanowires feature superior functional properties and mechanical strengths which have been used in micro/nanoelectromechanical systems and photovoltaic applications [6]. Veeramani et al presented a room-temperature synthesis of Mn 3 O 4 nanowires solely from water and manganese salt, catalyzed by iron oxide nanocrystals in the presence of piperazine-N,N I -bis(2-ethanesulfonic acid) (PIPES) [7]. Sambasivam et al synthesized single-crystalline Mn 3 O 4 nanowires using solvothermal technique [8].…”

Green synthesis, characterisation, and photocatalytic activity of manganese dioxide nanoparticles

“…Manganese oxide NPs have engrossed consideration due to their extensive applications in several fields such as catalysis, ion‐sieves, rechargeable batteries, chemical sensing devices, microelectronics [8] and optoelectronics [9]. Furthermore, due to the existence of numerous attachments for a diversity of usage, they are based against earth extra elements, as Mn is the twelfth most plenty element on the planet and the third most common transition element after Fe and Ti [10]. Moreover, the manganese dioxide nanoparticles (MnO 2 NPs) have a good photocatalytic activity for dye degradation [11, 12].…”