Sur quelques nouvelles phases de formule NaxMnO2 (x ⩽ 1)

Parant, Jean-Paul; Olazcuaga, R.; Devalette, Michel; Fouassier, C.; Hagenmuller, Paul

doi:10.1016/0022-4596(71)90001-6

Cited by 475 publications

(404 citation statements)

References 13 publications

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“…75 The high temperature form of Na 2/3 MnO 2 reported by Paulsen and Dahn, β-Na 0.7 MnO 2 , exhibits a monoclinic distortion, while the low temperature α form is essentially undistorted. 77 Stoyanova et al have reported an orthorhombic distortion (Cmcm) when quenching Na 2/3 MnO 2 from 1000…”

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confidence: 90%

Review—Manganese-Based P2-Type Transition Metal Oxides as Sodium-Ion Battery Cathode Materials

Clément

Bruce

Grey

2015

J. Electrochem. Soc.

438

388

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Sodium transition metal oxides (NaMO 2 ) with a P2 structure exhibit good Na + ion conductivity and are promising sodium-ion battery cathode materials. Manganese-based compounds have a high working potential vs. Na + /Na, and high capacity. Yet, the layered nature of these materials means that they are prone to structural rearrangements at high voltage/low Na contents, the phase transformations and Na + ion/vacancy ordering transitions resulting in capacity fade and poor reversibility. This review discusses the latest advances in the field and focuses mainly on recent work on Na y Mn 1-x M x O 2 (x, y ≤ 1, M = Ni, Mg, Li) compounds. We compare the different lithium and sodium transition metal layered oxides (P2, O3, etc.) and describe the structures and mechanisms observed on alkali (de)intercalation. The strategies used to enhance the electrochemical properties and stabilize the structural framework of sodium transition metal oxides are reviewed. We show how X-ray diffraction and 7 Li/ 23 Na solid-state Nuclear Magnetic Resonance can be combined to provide a detailed insight into the structural and electronic processes occurring upon electrochemical cycling of these materials. Why Are We Interested in Na-Ion Battery Cathodes?Together, the increasing demand for energy and the threat from Global Warming make electrical energy storage (EES) a world wide strategic priority. EES is expected to play a key role in the decarbonization of electric power sources. The two billion people worldwide not currently served by a reliable electricity supply are likely to be connected via local grids, for which EES is essential. While Li-ion batteries (LIBs) will play a role, a key challenge is to develop lower cost batteries that deliver safe, reliable storage with high cycle and calendar life. In this regard, Na-ion batteries (NIBs) are potentially important. NIBs operate in a similar fashion to LIBs, offering both advantages and disadvantages. Concerning the former, the ability to use Al instead of Cu as a current collector at the anode could substantially reduce cost. Na is also far more abundant in the Earth's crust than Li, and more widely distributed geographically. Regarding the disadvantages, the standard operating potential of Na metal is 300 mV more positive than Li metal. This generally translates into lower operating potentials for Na-ion systems, although the potential of a full cell depends on the difference in the chemical potentials of Na in the anode and cathode materials. There are considerable opportunities for scientists to develop new combinations of anode, electrolyte and cathode that are optimized for a variety of applications with different criteria such as high energy density, high power, and high operating potential. This has encouraged a rapid growth of interest in research into NIB components. Hard carbons show some promise as anodes, [1][2][3] but more must be done to improve performance. The cathode remains a major challenge and it is to this that we direct the current review. A comparative plot sho...

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confidence: 90%

Review—Manganese-Based P2-Type Transition Metal Oxides as Sodium-Ion Battery Cathode Materials

Clément

Bruce

Grey

2015

J. Electrochem. Soc.

438

388

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“…. For alkali ion deficient phases (x = 0.75) a strong monoclinic distortion may be observed: Nao.75Mn02(0 / 3) [13], KzCr02(0'3) (0.70 < z < 0.77) [14]. These last phases are isostructural with the JahnTeller distorted ct-NaMn02 [13] and NaNi02 [15].…”

Section: The Abc Abc (03) Oxygen Packingmentioning

confidence: 97%

Trigonal Prismatic or Octahedral Surrounding in Sheet Oxides ?

Delmas

Braconnier

Fouassier

et al. 1981

Zeitschrift Für Naturforschung B

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Abstract Layer Oxides, Intercalate, Trigonal Prismatic of Octahedral Surrounding According to the oxygen packing two types of alkali ion surroundings (octahedral or trigonal prismatic) are possible in the AxMO2 sheet oxides or the related A2MO3 compounds. The stability of both environments is discussed from the geometrical and electrostatic view points. Structural transitions to metastable forms can be induced by high pressure, intercalation, desintercalation or exchange reactions. The possibility of room temperature transformations can be anticipated from the relationships between the various oxygen packings.

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“…En algunos de los difractogramas de esta serie los máximos son anchos, lo que indica que las fases formadas no son tan cristalinas como en el caso de las obtenidas a partir de las muestras potásicas; los difractogramas no son tan "limpios", registrándose muchos picos de baja intensidad, debido a la gran variedad de compuestos de estequiometría próxima que forma el sodio con el manganeso y oxígeno [35]. La relación glucosa/catión no modifica las fases cristalinas presentes en los sólidos obtenidos tras la calcinación, observándose únicamente ligeras variaciones en la intensidad o la anchura de los picos de las distintas fases formadas.…”

Section: Sistemas Calcinadosunclassified

“…La fase Na 2 Mn 5 O 10 (Na 0.4 MnO 2 ) es una estructura tipo túnel (2x3) de la familia de la romanechita [8]. El compuesto Na 0.2 MnO 2 ha sido identificado por Parant y col. [35] como perteneciente a la familia de las holanditas, con estructura túnel (2x2), y cuyo tamaño de túnel es mucho menor del habitual debido al menor tamaño del catión Na + , con respecto al de K + . Para las muestras sódicas intercambiadas se obtienen resultados prácticamente iguales para ambas series, independientemente de la relación glucosa/ catión utilizada, como era de esperar a la vista de los resultados obtenidos para las muestras originales no calcinadas.…”

Section: Sistemas Calcinadosunclassified

Birnesitas obtenidas mediante cambio iónico. Evolución estructural con la calcinación

Rives¹,

Arco²,

Prieto³

2004

Bol. Soc. Esp. Ceram. Vidr.

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Se han preparado birnesitas con Na + o K + en la interlámina mediante un método sol-gel, con una relación inicial glucosa/catión de 1 y 1.5. Estas muestras se han sometido a cambio iónico con los cationes Li + , Mg 2+ y Cu 2 , caracterizando las muestras intercambiadas por diversas técnicas (análisis químico elemental, difracción de rayos X, espectroscopía FT-IR, análisis térmico y determinación de superficie específica). En ningún caso se alcanza un cambio iónico completo de los iones sodio o potasio iniciales, aunque el sodio se intercambia en mayor medida que el potasio. El intercambio es más efectivo al incorporar el Li + , menor en el caso del Cu 2+ y menos eficiente, todavía, al incorporar Mg 2+. El cambio iónico se produce topotácticamente, manteniéndose en todos los casos la estructura laminar con una distancia interlaminar de, aproximadamente, 7 Å. Las muestras son estables hasta 600 ºC; a partir de esta temperatura se produce la transformación a estructura túnel 2x2 (criptomelano) en el caso de la birnesita de K y a la espinela de Li-Mn (LiMn 2 O 4 ) en el caso de tener Li en la interlámina. Palabras claves: birnesita, óxidos de Mn, no estequiometría. Birnessites prepared by ion exchange. Structural evolution with temperatureBirnessites containing Na + or K + in the interlayer have been prepared following a sol-gel method, with an initial glucose/cation ratio of 1 or 1.5. The solids have been submitted to ion exchange with Li , and all the materials have been characterised by several physicochemical techniques (elemental chemical analysis, X-ray diffraction, FT-IR spectroscopy, thermal analysis and specific surface area assessment). Total cation exchange was not achieved in any case, although sodium is better exchanged than potassium. Exchange is larger for Li + , lower for Cu 2+ and even lower for Mg 2+. Ionic exchange is topotactic, and the layered structure is maintained in all cases, with an interlayer spacing close to 7 Å. The samples are stable up to 600 °C; above this temperature cryptomelane (a 2x2 tunnel structure) is formed in most of the samples containing potassium, while LiMn 2 O 4 spinel is formed is Li was present in the birnessite.

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Sur quelques nouvelles phases de formule NaxMnO2 (x ⩽ 1)

Cited by 475 publications

References 13 publications

Review—Manganese-Based P2-Type Transition Metal Oxides as Sodium-Ion Battery Cathode Materials

Review—Manganese-Based P2-Type Transition Metal Oxides as Sodium-Ion Battery Cathode Materials

Trigonal Prismatic or Octahedral Surrounding in Sheet Oxides ?

Birnesitas obtenidas mediante cambio iónico. Evolución estructural con la calcinación

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