Gemischte Übergangsmetalloxide: Design, Synthese und energierelevante Anwendungen

Abstract

Seit kurzem findet eine Familie gemischter Übergangsmetalloxide (mixed transition‐metal oxides, MTMOs; beschrieben durch AxB3−xO4; A, B=Co, Ni, Zn, Mn, Fe usw.) mit stöchiometrischen oder gar nichtstöchiometrischen Zusammensetzungen (typischerweise in Spinellstruktur) weltweit Interesse. Diese MTMOs dürften dank ihrer ausgezeichneten elektrochemischen Eigenschaften große Bedeutung für kostengünstige und umweltfreundliche Technologien zur Energiespeicherung/‐umwandlung erlangen. In diesem Aufsatz fassen wir die jüngsten Fortschritte beim rationalen Design von MTMOs mit steuerbaren Formen, Größen, Zusammensetzungen und Mikro‐/Nanostrukturen sowie ihren Anwendungsmöglichkeiten zusammen, z. B. als Elektrodenmaterialien für Lithium‐Ionen‐Batterien und elektrochemische Kondensatoren oder als effiziente Elektrokatalysatoren bei der Sauerstoffreduktionsreaktion in Sauerstoff/Luft‐Batterien und Brennstoffzellen. Zum Schluss diskutieren wir die weitere mögliche Entwicklung von MTMOs für die nächste Technologiegeneration der elektrochemischen Energiespeicherung/‐umwandlung.

Hydrothermal Synthesis of Unique Hollow Hexagonal Prismatic Pencils of Co3V2O8⋅n H2O: A New Anode Material for Lithium‐Ion Batteries

“…[11][12][13] Nevertheless,i nc ontrast to the active research on the synthesis of mixed transition-metal oxides (TMOs;d onated as A x B 3-x O 4 ;A ,B= Co,N i, Zn, Mn, Fe) [11] as important mixed-metal oxides,m etal vanadates appear to be underexplored, likely because of the lack of suitable synthetic methods. [14][15][16] Herein, we report the hydrothermal synthesis of the new phase of Co 3 V 2 O 8 ·n H 2 Ow ith non-spherical structures and ac omplex geometry.W ith properly manipulating the precursor system and thus reaction kinetics,the growth of certain specific planes could be inhibited simply by changing the NaOH content in the presence of NH 4 + without the use of any template or surfactant;t his approach resulted in the gradual evolution of solid hexagonal prismatic pencils into concave hexagonal prismatic pencils and finally into hollow hexagonal prismatic pencils (HHPPs).…”

Spatially Self‐Confined Formation of Ultrafine NiCoO2 Nanoparticles@Ultralong Amorphous N‐Doped Carbon Nanofibers as an Anode towards Efficient Capacitive Li+ Storage

“…With the rapid growth of electric vehicles (EVs), hybrid EVs, and portable electronic devices,e lectrochemical energy storage is ak ey to tackling many fundamentalp roblemsi nt he field of electronic devices. [1][2][3] Over the past decades, rechargeable secondary Li-ion batteries (LIBs) have becomet he primary energy source for thesea pplicationsd ue to their high reversible capacities, highc ost efficiency,l ong lifetime, low self-discharge,a nd environmental friendliness. [4,5] Unfortunately,t he commercial graphite anode is still limited seriously by its low capacity(% 372 mA h À1 g À1 )a nd modest rate capability.T herefore, anode materials with high theoretical capacity are urgently required for practical applications of LIBs.…”

“…[3,6] ParticularlyN i-Co-based mixed oxides have attracted much attention,thanks to their better electronic conductivity and richer redox reactions comparedt ot heir single-phase counterparts. [3,7] Face-centered cubic NiCoO 2 (NCO)h as recently stood out from Ni-Co-based mixed oxides as an emerging anode candidate, [8][9][10][11] beside the well-known spinel NiCo 2 O 4 . [3,12] However,c ubic-phase NCO has rarely been researched as anode for LIBs (fewer than ten contributions in the literature).…”

In Situ Growth and Characterization of Metal Oxide Nanoparticles within Polyelectrolyte Membranes

“…Doing so endears the composite material to applications in heterogeneous catalysis, [1][2][3] sensors [4] for both biological compounds [5] and chemical warfare agents; [6,7] actuators, [8] optoelectronics, [9,10] energy storage, [11] and chemical protection. The method is demonstrated drawing on the example of Nafion membranes and avariety of metal oxides with an emphasis placed on zinc oxide.T he in situ formation of nanoparticles is controlled by changing the solvent composition and conditions of synthesis that for the first time allows one to tailor not only the size, but also the nanoparticle shape,g iving ap reference to growth of ap articular crystal facet.…”

“…Doing so endears the composite material to applications in heterogeneous catalysis, [1][2][3] sensors [4] for both biological compounds [5] and chemical warfare agents; [6,7] actuators, [8] optoelectronics, [9,10] energy storage, [11] and chemical protection. Doing so endears the composite material to applications in heterogeneous catalysis, [1][2][3] sensors [4] for both biological compounds [5] and chemical warfare agents; [6,7] actuators, [8] optoelectronics, [9,10] energy storage, [11] and chemical protection.…”