Electrochemical Behaviour of Carbon Anodes in Na3AlF6-K3AlF6-Based Low-Melting Electrolytes for Aluminium Electrolysis

Some types of anodes that could replace the usual carbon anodes in aluminium production by the Hall-Heroult process are based on SnO2. The present investigation deals with SnO2-Sb2O3-CuO ceramics having an SnO2 content of ≥96%), Sb2O3 and CuO being dopants. The ceramic pellets, thermally treated at 1400 °C for 4 hours, were analysed by X-ray diffraction and IR spectroscopy. The structural analysis of the samples evidenced an SnO2 (ss) type solid solution. All samples were electronically conductive (small negative values of the Seebeck coefficients), having an activation energy ranging within 0.02 - 0.3 eV.The anodic polarisation curves obtained with those anodes in an electrolyte of 88% Na3AlF6, 7% Al2O3 and 5% CaF2 were studied. The results were correlated with the microstructure of the investigated samples.

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Microstructure and Electrochemical Behaviour of some SnO2-based Inert Electrodes in Aluminium Electrolysis

Zeitschrift für Naturforschung A ◽

10.1515/zna-2002-1-210 ◽

2002 ◽

Vol 57 (1-2) ◽

pp. 71-75 ◽

Cited By ~ 11

Author(s):

Ana-Maria Popescu ◽

Suzana Mihaiu ◽

Stefania Zuca

Keyword(s):

Solid Solution ◽

Structural Analysis ◽

Ir Spectroscopy ◽

Electrochemical Behaviour ◽

X Ray Diffraction ◽

X Ray ◽

Seebeck Coefficients ◽

Aluminium Production ◽

Anodic Polarisation ◽

Carbon Anodes

Some types of anodes thai could replace die usual carbon anodes in aluminium production by die Hall-Keroult process are based on SnO2. The presenr Investigation deals nidi SnO2-Sb2O3-CuO ceramics having an SnO2. conrent of ≥ 96%), Sb2O3, and CuO being dopants The ceramic pellets, thermally treated at 1400 °C for 4 hours, were analysed by X-ray diffraction and IR. spectroscopy. The structural analysis of the samples evidenced an SnO2(88) type solid solution. All samples were electronically conductive (small negative values of the Seebeck coefficients), having an sanation energy ranging within 0.02 - 0.3 eV.The anodic polarisation curves obtained with those anodes in an electrolyte of 88 % Na3AlF6, 7% Al2O3, and 5% CaF2 were studied- The results were correlated with the microstrucrure of die invesagated samples.

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Algae-derived hard carbon anodes for Na-ion batteries

Journal of Applied Electrochemistry ◽

10.1007/s10800-021-01609-2 ◽

2021 ◽

Author(s):

Eugenio Gibertini ◽

Francesco Liberale ◽

Carlo Dossi ◽

Gilberto Binda ◽

Barbara Mattioli ◽

...

Keyword(s):

Low Cost ◽

Electrochemical Behaviour ◽

Active Material ◽

Added Value ◽

Environmentally Benign ◽

X Ray Diffraction ◽

Hard Carbon ◽

Decomposition Products ◽

Na Ions ◽

Carbon Anodes

Abstract In this work, the production of low cost and environment friendly anodes for sodium ion batteries is investigated. Algae are selected as bio-source of non-graphitic Hard Carbon (HC) with open structure acting as intercalation active material for Na ions storage. Chlorella vulgaris algae were pyrolyzed at temperatures comprised between 800 and 1100 °C. The decomposition products have been characterized with Scanning Electrode Microscope (SEM) and X-Ray Diffraction (XRD) analyses and their structure compared to one of the synthetic commercial HC. Thermogravimetric analysis (TGA) allowed to assess the decomposition process throughout the selected temperature scan. The obtained algae-derived HC is tested as anodic material for Na-ion battery, investigating the effect of pyrolysis temperature on the electrochemical behaviour. Their performances are compared with respect to a commercial synthetic HC active material. The results allow to consider algae as an environmentally benign and sustainable high added-value material for the production of HC anodes for Na-ion batteries. Graphic abstract

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