Ecofriendly Synthesis of Waste-Tire-Derived Graphite Nanoflakes by a Low-Temperature Electrochemical Graphitization Process toward a Silicon-Based Anode with a High-Performance Lithium-Ion Battery.

Here, the successful transformation of graphitic carbon with a high degree of graphitization and a nanoflake structure from pyrolytic tire carbon black was demonstrated. First, amorphous carbon black with a porous structure was obtained after pyrolysis and simple preacid treatments. Subsequently, the carbon black was converted into a highly graphitic structure at a relatively low temperature (850 °C) through a facile electrochemical route using molten salt, which is ecofriendly and has high potential for large-scale graphitization compared to conventional incineration techniques. Moreover, we further improved the crystallinity and uniformity of the product simultaneously by directly mixing the metal oxide catalyst Fe2O3 with a carbon precursor. The mechanism of this metal-catalyzed electrochemical graphitization has been discussed in detail. To confirm their potential in practical applications, the as-prepared graphitized nanoflakes were used as conductive additives for silicon anodes in lithium-ion batteries, which showed a performance comparable to those utilizing commercial Super-P additives, exhibiting an initial Coulombic efficiency of approximately 79.7% and a high capacity retention of approximately 45.8% after 100 cycles with a reversible capacity of 1220 mAh g-1 at a current rate of 400 mA g-1. Hence, successfully recovered waste-tire-derived carbon black utilizing a low-temperature Fe2O3-catalyzed electrochemical process opens a pathway in low-temperature graphitization toward a sustainable value-added application in the field of energy storage.

Three-Dimensional CuO/TiO2 Hybrid Nanorod Arrays Prepared by Electrodeposition in AAO Membranes as an Excellent Fenton-Like Photocatalyst for Dye Degradation.

Three-dimensional (3D) CuO/TiO2 hybrid heterostructure nanorod arrays (NRs) with noble-metal-free composition, fabricated by template-assisted low-cost processes, were used as the photo-Fenton-like catalyst for dye degradation. Here, CuO NRs were deposited into anodic aluminum oxide templates by electrodeposition method annealed at various temperatures, followed by deposition of TiO2 thin films through E-gun evaporation, resulting in the formation of CuO/TiO2 p-n heterojunction. The distribution of elements and compositions of the CuO/TiO2 p-n heterojunction were analyzed by EDS mapping and EELS profiles, respectively. In the presence of H2O2, CuO/TiO2 hybrid structure performed more efficiently than CuO NRs for Rhodamine B degradation under the irradiation of 500-W mercury-xenon arc lamp. This study demonstrated the effect of length of CuO NRs, on the photo-degradation performance of CuO NRs as well as CuO/TiO2 heterostructure. The optimized CuO/TiO2 hybrid NR array structure exhibited the highest photo-degradation activity, and the mechanism and role of photo-Fenton acting as the catalyst in photo-degradation of dye was also investigated.

High-Performance Rechargeable Aluminum-Selenium Battery with a New Deep Eutectic Solvent Electrolyte: Thiourea-AlCl3.

Aluminum-sulfur batteries (ASBs) have attracted substantial interest due to their high theoretical specific energy density, low cost, and environmental friendliness, while the traditional sulfur cathode and ionic liquid have very fast capacity decay, limiting cycling performance because of the sluggishly electrochemical reaction and side reactions with the electrolyte. Herein, we demonstrate, for the first time, excellent rechargeable aluminum-selenium batteries (ASeBs) using a new deep eutectic solvent, thiourea-AlCl3, as an electrolyte and Se nanowires grown directly on a flexible carbon cloth substrate (Se NWs@CC) by a low-temperature selenization process as a cathode. Selenium (Se) is a chemical analogue of sulfur with higher electronic conductivity and lower ionization potential that can improve the battery kinetics on the sluggishly electrochemical reaction and the reduction of the polarization where the thiourea-AlCl3 electrolyte can stabilize the side reaction during the reversible conversion reaction of Al-Se alloying processes during the charge-discharge process, yielding a high specific capacity of 260 mAh g-1 at 50 mA g-1 and a long cycling life of 100 times with a high Coulombic efficiency of nearly 93% at 100 mA g-1. The working mechanism based on the reversible conversion reaction of the Al-Se alloying processes, confirmed by the ex situ Raman, XRD, and XPS measurements, was proposed. This work provides new insights into the development of rechargeable aluminum-chalcogenide (S, Se, and Te) batteries.

Three-Dimensional Molybdenum Diselenide Helical Nanorod Arrays for High-Performance Aluminum-Ion Batteries.

The rechargeable aluminum-ion battery (AIB) is a promising candidate for next-generation high-performance batteries, but its cathode materials require more development to improve their capacity and cycling life. We have demonstrated the growth of MoSe2 three-dimensional helical nanorod arrays on a polyimide substrate by the deposition of Mo helical nanorod arrays followed by a low-temperature plasma-assisted selenization process to form novel cathodes for AIBs. The binder-free 3D MoSe2-based AIB shows a high specific capacity of 753 mAh g-1 at a current density of 0.3 A g-1 and can maintain a high specific capacity of 138 mAh g-1 at a current density of 5 A g-1 with 10 000 cycles. Ex situ Raman, XPS, and TEM characterization results of the electrodes under different states confirm the reversible alloying conversion and intercalation hybrid mechanism during the discharge and charge cycles. All possible chemical reactions were proposed by the electrochemical curves and characterization. Further exploratory works on interdigital flexible AIBs and stretchable AIBs were demonstrated, exhibiting a steady output capacity under different bending and stretching states. This method provides a controllable strategy for selenide nanostructure-based AIBs for use in future applications of energy-storage devices in flexible and wearable electronics.

3D CoMoSe4 Nanosheet Arrays Converted Directly from Hydrothermally Processed CoMoO4 Nanosheet Arrays by Plasma-Assisted Selenization Process Toward Excellent Anode Material in Sodium-Ion Battery.

In this work, three-dimensional (3D) CoMoSe4 nanosheet arrays on network fibers of a carbon cloth denoted as CoMoSe4@C converted directly from CoMoO4 nanosheet arrays prepared by a hydrothermal process followed by the plasma-assisted selenization at a low temperature of 450 °C as an anode for sodium-ion battery (SIB) were demonstrated for the first time. With the plasma-assisted treatment on the selenization process, oxygen (O) atoms can be replaced by selenium (Se) atoms without the degradation on morphology at a low selenization temperature of 450 °C. Owing to the high specific surface area from the well-defined 3D structure, high electron conductivity, and bi-metal electrochemical activity, the superior performance with a large sodium-ion storage of 475 mA h g-1 under 0.5-3 V potential range at 0.1 A g-1 was accomplished by using this CoMoSe4@C as the electrode. Additionally, the capacity retention was well maintained over 80 % from the second cycle, exhibiting a satisfied capacity of 301 mA h g-1 even after 50 cycles. The work delivered a new approach to prepare a binary transition metallic selenide and definitely enriches the possibilities for promising anode materials in SIBs with high performances.