Unique properties of α-NaFeO2: De-intercalation of sodium via hydrolysis and the intercalation of guest molecules into the extract solution

Monyoncho, Evans A.; Bissessur, Rabin

doi:10.1016/j.materresbull.2013.03.027

Cited by 46 publications

(39 citation statements)

References 19 publications

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“…However, the porous product scale confirms the formation of the volatile products. Based on this and previous study results [1,2,3,4,5,6,7,8,9,18], the following corrosion mechanism is proposed: at initial stages of the corrosion, the Na 2 SO 4 and the H 2 O can react with the Fe to produce NaFeO 2 and H 2 SO 4(g) : 4Fe + 3O 2 + 2H 2 O +2Na 2 SO 4 → 4NaFeO 2 + 2H 2 SO 4 (g) Based on the above results and discussion as well as our previous study [9,17], in the electrochemical corrosion reaction coupled with a chemical corrosion reaction, the H 2 SO 4 would electrochemically react with the Fe. Cathodic reaction: H 2 SO 4 + 2e - → SO 4 2- + H 2 Anodic reaction: Fe − 2e - → Fe 2+ …”

Section: Discussionmentioning

confidence: 66%

“…However, the product scale changes to be uneven after corrosion for 10 h. In addition, the morphologies of needle- and nubbly-shape appear which are not seen in the case after 1 h. From the corresponding EDAX results (see Figure 10), the needle-shape product is composed of Fe, Na, and O elements, while Fe and O are the only two elements detected in the nubbly structure. According to the XRD and the previous research results [17], the needle-shape product is most likely a mixture of Fe 2 O 3 and NaFeO 2 and the nubbly product may be Fe 3 O 4 . Figure 10 shows the cross-sectional morphologies of the corrosion scale on the pure Fe after corrosion for 1 h and 10 h under a Na 2 SO 4 deposit in a H 2 O + O 2 atmosphere at 500 °C.…”

Section: Resultsmentioning

confidence: 76%

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The Corrosion Behavior of Pure Iron under Solid Na2SO4 Deposit in Wet Oxygen Flow at 500 °C

et al. 2014

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The corrosion behavior of pure Fe under a Na2SO4 deposit in an atmosphere of O2 + H2O was investigated at 500 °C by thermo gravimetric, and electrochemical measurements, viz. potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and surface characterization methods viz. X-ray diffraction (XRD), and scanning electron microscope (SEM)/energy dispersive spectroscopy(EDS). The results showed that a synergistic effect occurred between Na2SO4 and O2 + H2O, which significantly accelerated the corrosion rate of the pure Fe. Briefly, NaFeO2 was formed in addition to the customary Fe oxides; at the same time, H2SO4 gas was produced by introduction of water vapor. Subsequently, an electrochemical corrosion reaction occurred due to the existence of Na2SO4, NaFeO2, and H2O. When this coupled to the chemical corrosion reaction, the progress of the chemical corrosion reaction was promoted and eventually resulted in the acceleration of the corrosion of the pure Fe.

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Section: Discussionmentioning

confidence: 66%

Section: Resultsmentioning

confidence: 76%

The Corrosion Behavior of Pure Iron under Solid Na2SO4 Deposit in Wet Oxygen Flow at 500 °C

et al. 2014

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“…The interlayer spacing becomes larger due to increased repulsion between adjacent oxide layers because the shielding effect by the positively charged Na ions decreases. [38][39][40][41][42] (iii) Layered oxides can also uptake CO 2 on exposure to air, involving the unprecedented room temperature insertion of CO 3 2− within the TM layers of the Na-based metal oxide, which is simultaneously balanced by the oxidation of TM in the lattice to higher valence. [43] The mechanisms proposed above all result in the formation of electrochemically inactive NaOH or Na 2 CO 3 on the surface of active materials, leading to the deteriorated battery performance.…”

Section: Challengesmentioning

confidence: 99%

“…[56] Besides the low reversible capacity due to Fe 3+ migration and Jahn-Teller effect of Fe 4+ during cycling, another major disadvantage of NaFeO 2 electrode material is that Na + would be exchanged by H + when NaFeO 2 is in contact with water. [40] Out of this factor, NaFeO 2 changes quickly into FeOOH and NaOH when exposed in moisture and Na 2 CO 3 and/or NaHCO 3 might also form on the surface of the material by uptake of CO 2 . Such Na + /H + ion exchange gives rise to the storage instability www.advenergymat.de in O3-type NaFeO 2 in ambient environment, which requires a harsh environment for storage and preparing electrodes.…”

Section: Single-metal-based Oxides Peculiar To Sibsmentioning

confidence: 99%

Layered Oxide Cathodes for Sodium‐Ion Batteries: Phase Transition, Air Stability, and Performance

Wang

You

Yin

et al. 2017

Advanced Energy Materials

660

510

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sources into large-scale grids, inexpensive, efficient, and fast-responding electrical energy storage (EES) systems are essential to store the off-peak energy and releasing the stored energy during the onpeak period. Among various EES systems, rechargeable batteries represent one of the most competitive technologies because of their high conversion efficiency and environmental friendliness. [1][2][3][4] For stationary EES systems, batteries with low cost, high safety, high rate capability, and long cycle stability are highly desired.Lithium (Li)-ion batteries (LIBs) have achieved great success in the market of portable electronics and electric vehicles since their commercialization by Sony Company in 1991. However, the shortage of Li resources in nature gives rise to a concern about its sustainable development in grid scale. Compared with Li, sodium resource has rich natural abundance in the earth crust and a worldwide distribution, consequently leading to a low price of sodium-based raw materials (e.g., the cost of Na 2 CO 3 is about 25-30 times lower than that of Li 2 CO 3 ). Besides, sodium has a suitable redox potential (E 0 (Na + /Na) = −2.71 V versus standard hydrogen electrode (SHE), 0.3 V above that of Li + /Li) and similar physical and chemical properties with lithium. [5,6] Therefore, rechargeable sodium-ion batteries (SIBs), which have a similar "rockingchair" working principle of LIBs, are emerging as an appealing choice as alternatives for LIBs. Note that it is difficult for SIBs to bypass LIBs in terms of energy densities because of the much higher weight of Na and lower standard electrochemical potential. [7][8][9][10] Nevertheless, the use of low-cost materials, including inexpensive Na-based raw materials and Al current collectors for both cathodes and anodes in SIBs, could significantly reduce the cost. In this case, SIBs could be applied where cost-effectiveness rather than energy density is the most critical issue, e.g., in the field of large-scale EES. As a result, sodiumbased electroactive materials are enjoying renewed interest especially for very low cost systems for grid storage. [11,12] Given that cathode materials are the key component that determines energy density and cost, tremendous efforts have been devoted to exploring suitable positive electrode materials with high reversible capacity, rapid Na ions insertion/extraction, and good cycling stability in the past few years. [13,14] A broad range of compounds, including layered oxides, polyanionic frameworks, hexacyanoferrates, and organics, haveThe increasing demand for replacing conventional fossil fuels with clean energy or economical and sustainable energy storage drives better battery research today. Sodium-ion batteries (SIBs) are considered as a promising alternative for grid-scale storage applications due to their similar "rockingchair" sodium storage mechanism to lithium-ion batteries, the natural abundance, and the low cost of Na resources. Searching for appropriate electrode materials with acceptable electrochemical perfor...

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“…(The C rate is defined as the current that delivers a nominal capacity in 1 h, and the nominal capacity here is defined as one-electron redox of iron, i.e., 241 mA g −1 ). Another drawback of NaFeO 2 as an electrode material is the Na + /H + ion exchange when NaFeO 2 is in contact with water [44]. NaFeO 2 changes into FeOOH and NaOH (Na 2 CO 3 and/or NaHCO 3 by uptake of CO 2 ).…”

Section: Layered Oxides As Na Insertion Host Materialsmentioning

confidence: 99%

Recent research progress on iron- and manganese-based positive electrode materials for rechargeable sodium batteries

Yabuuchi

Komaba

2014

Science and Technology of Advanced Materials

217

156

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Large-scale high-energy batteries with electrode materials made from the Earth-abundant elements are needed to achieve sustainable energy development. On the basis of material abundance, rechargeable sodium batteries with iron- and manganese-based positive electrode materials are the ideal candidates for large-scale batteries. In this review, iron- and manganese-based electrode materials, oxides, phosphates, fluorides, etc, as positive electrodes for rechargeable sodium batteries are reviewed. Iron and manganese compounds with sodium ions provide high structural flexibility. Two layered polymorphs, O3- and P2-type layered structures, show different electrode performance in Na cells related to the different phase transition and sodium migration processes on sodium extraction/insertion. Similar to layered oxides, iron/manganese phosphates and pyrophosphates also provide the different framework structures, which are used as sodium insertion host materials. Electrode performance and reaction mechanisms of the iron- and manganese-based electrode materials in Na cells are described and the similarities and differences with lithium counterparts are also discussed. Together with these results, the possibility of the high-energy battery system with electrode materials made from only Earth-abundant elements is reviewed.

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Unique properties of α-NaFeO2: De-intercalation of sodium via hydrolysis and the intercalation of guest molecules into the extract solution

Cited by 46 publications

References 19 publications

The Corrosion Behavior of Pure Iron under Solid Na2SO4 Deposit in Wet Oxygen Flow at 500 °C

The Corrosion Behavior of Pure Iron under Solid Na2SO4 Deposit in Wet Oxygen Flow at 500 °C

Layered Oxide Cathodes for Sodium‐Ion Batteries: Phase Transition, Air Stability, and Performance

Recent research progress on iron- and manganese-based positive electrode materials for rechargeable sodium batteries

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