Repurposing Waste Tires as Tunable Frameworks for Use in Sodium-Ion and Lithium–Sulfur Batteries

Abstract

Selectively resourcing electrode components can provide a significant advantage in the uptake of next generation battery systems especially considering the performance of currently incumbent lithium-ion battery technology. This work systematically explores the use of a waste stream to generate electrode components and the influence that treatment and preparation factors have on electrochemical performance. A series of carbonaceous materials derived from waste rubber tires are prepared, involving pyrolysis at 700 and 900 °C as well as physical activation using a feed of CO 2 gas. Results from Raman spectroscopy and X-ray powder diffraction (XRD) show an increase in graphitic character and larger particle size distribution of the carbon with increasing temperatures of pyrolyzation. They also reveal the impact of air and moisture on the evolution of crystalline impurities such as ZnS, CaCO 3 , and Ca(OH) 2 , and consequently their impact on the evolution of the carbon morphology. Galvanostatic cycling of Na-ion and Li−S cells involving the pyrolyzed rubber tires as an electrode component reveal different priorities as to which parameters to improve when designing materials for different cell systems. While higher specific capacities are achieved with more graphitic carbon morphologies in Na half-cells (300 mAh g −1 discharge capacity maintained after 20 cycles at 10 mA g −1 ), less graphitic morphologies were observed to reduce capacity fading experienced in Li−S cells (1003 mAh g −1 discharge capacity maintained after 18 cycles at 167.2 mA g −1 , ∼ 76% of initial value). Ex situ Raman, XRD, and X-ray absorption near-edge structure (XANES) spectroscopies were used to elucidate the mechanisms involved in post electrochemical treatment. This work highlights a pathway to use waste tires to generate valuable electrode components (active material in Na half-cells and S hosts in Li−S cells), and a similar methodology could be applied to other waste streams.

Production and Upgrading of Recovered Carbon Black from the Pyrolysis of End-of-Life Tires

“…Moreover, after further processing [ 68 , 69 ], these activated carbon materials can be employed in a large variety of fields, as depicted in Figure 4 . In recent studies, activated rCB samples were investigated as adsorbents for the separation of compounds in gaseous [ 70 , 71 , 72 ] and liquid [ 73 ] phases (e.g., adsorption of dyes [ 74 , 75 ], organic compounds [ 76 , 77 , 78 , 79 ], and heavy metals [ 80 , 81 , 82 ]), as conductive additives for carbon electrodes of sodium and lithium batteries [ 83 , 84 , 85 , 86 ], as supercapacitors [ 87 ], as catalysts [ 88 , 89 ] and as nanomaterial precursors [ 90 , 91 ]. Even though rCB has been identified as a potential solid fuel (the HHV is within 25 to 34 MJ/kg [ 9 , 21 ]), its low reactivity, slow oxidation kinetics, small particle size, and low bulk density explain why rCB combustion studies are rarely found.…”

Investigation of low molecular weight sulfur–limonene polysulfide electrodes in Li–S cells

“…C K and S K-Edge XANES measurements were conducted on the so X-ray beamline at the Australian Synchrotron 41 following the same procedures outlined in previous work. 12,13,20,21 For normalization of the beam energy between scans all samples were measured simultaneously with TEY of an Au mesh situated in front of the sample (I 0 signal), i.e., sample signal divided by the I 0 TEY signal. For edge energy calibrations, S K-edge spectra of the samples were also simultaneously measured with a MoS 2 reference foil maintained in the beamline with a known absorption edge centered at 2471.2 eV, and a pyrolytic graphite (HOPG) reference foil centered at 291.65 (26) eV for C K-edge spectra.…”

“…For C K-edge spectra, normalization to account for contributions from internal carbon contamination of the beamline was achieved by scanning a clean Si photodiode reference following the procedure outlined by Watts et al 42 Calibration and normalization of the C and S K-edge XANES data were performed using the Quick AS NEXAFS Tool (QANT) macro developed for Igor Pro. 43 13 C NMR experiments were performed on a Bruker Biospin Avance III 300 MHz spectrometer equipped with a wide bore 7 T superconducting magnet (75 MHz for 13 C and 300 MHz for 1 H). Aer drying inside an Ar-lled glovebox, approximately 80 mg of as-synthesised copolymer was packed into 4 mm outer diameter zirconia rotors with Kel-F® caps and spun to 6.5 kHz at the magic angle for measurement.…”

“…Aer drying inside an Ar-lled glovebox, approximately 80 mg of as-synthesised copolymer was packed into 4 mm outer diameter zirconia rotors with Kel-F® caps and spun to 6.5 kHz at the magic angle for measurement. Tetramethylsilane (TMS, 0.0 ppm) and solid adamantane (CH 2 peak at 38.48 ppm as a secondary reference) were used as references for the 13 C chemical shis. 13 C NMR spectra were acquired using a 1 H-13 C Hartman-Hahn cross-polarization with a 1 ms contact pulse ramped from 70-100% for polarization transfer.…”

“…Tetramethylsilane (TMS, 0.0 ppm) and solid adamantane (CH 2 peak at 38.48 ppm as a secondary reference) were used as references for the 13 C chemical shis. 13 C NMR spectra were acquired using a 1 H-13 C Hartman-Hahn cross-polarization with a 1 ms contact pulse ramped from 70-100% for polarization transfer. A 40 ms gated decoupling time was used to suppress the signals of the protonated carbon species.…”