ABSTRACT
The pursuit of safer and high-performance lithium-ion batteries (LIBs) has triggered extensive research activities on solid-state batteries, while challenges related to the unstable electrode-electrolyte interface hinder their practical implementation. Polymer has been used extensively to improve the cathode-electrolyte interface in garnet-based all-solid-state LIBs (ASSLBs), while it introduces new concerns about thermal stability. In this study, we propose the incorporation of a multi-functional flame-retardant triphenyl phosphate additive into poly(ethylene oxide), acting as a thin buffer layer between LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode and garnet electrolyte. Through electrochemical stability tests, cycling performance evaluations, interfacial thermal stability analysis and flammability tests, improved thermal stability (capacity retention of 98.5% after 100 cycles at 60 °C, and 89.6% after 50 cycles at 80 °C) and safety characteristics (safe and stable cycling up to 100 °C) are demonstrated. Based on various materials characterizations, the mechanism for the improved thermal stability of the interface is proposed. The results highlight the potential of multi-functional flame-retardant additives to address the challenges associated with the electrode-electrolyte interface in ASSLBs at high temperature. Efficient thermal modification in ASSLBs operating at elevated temperatures is also essential for enabling large-scale energy storage with safety being the primary concern.
ABSTRACT
Solid-state batteries (SSBs), which have high energy density and are safe, are recognized as an important field of study. However, the poor interfacial contact with high resistance, the dendrite problem, and the volume change of the metallic lithium anode prevent the use of SSBs. Li0.5La0.5TiO3 (LLTO) particles and molten lithium were used to create a high-performance LLTO-Li composite lithium with a sequential ion-conducting phase. With garnet electrolytes, this lithium has better wettability and reduced surface tension. To compensate for the lithium depletion that occurs during stripping, the Li-Ti phase with a high ionic diffusion coefficient that forms in the anode can rapidly transport lithium from the bulk to the solid-state interface, ensuring tight interface contact, preventing the formation of gaps, and homogenizing the current and Li+ flux. The LLTO-Li| LLZTO| LLTO-Li symmetric cell exhibits a good cyclic stability of 1000 h at room temperature, a low interfacial resistance of 22 Ω cm2, and a high critical current density of 1.2 mA cm-2. Furthermore, fully built cells with a LiFePO4 cathode showed outstanding cycling performance, maintaining 95% of their capacity after 900 cycles at 1 C and 92% capacity retention after 100 cycles at 2 C.
ABSTRACT
The photocatalytic degradation of conventional and emerging pollutants (i.e., methyl, ethyl, and butyl parabens) was investigated under light irradiation with 315-1050 nm wavelength using core-shell zinc doped hexacyanoferrate@Prussian blue nanoparticles. Different synthesis parameters including precursors loading, drying temperature and different metal ions precursors were studied. The ten different composite systems obtained, were investigated for the photodegradation of methylene blue in deionized water. The optimal performance photocatalyst (20 mg/L) photodegrade 94% of 10 ppm methylene blue within 24 min. The optimized sample was further used for the photodegradation of methylene blue in municipal wastewater matrix; it completely degraded the methylene blue after 51 min. Finally, the developed nanoparticles were investigated for the photodegradation of parabens. The chemical oxygen demand showed 30% of parabens was degraded in the municipal wastewater matrix. The results of this research show that ZnHCF@PB nanoparticles could be used for the effective photocatalytic remediation of conventional and emerging pollutants, i.e., parabens. STATEMENT OF ENVIRONMENTAL IMPLICATION: Through this study, it is anticipated that ZnO-derived ZnHCF@PB NPs can achieve a bandgap of 1.11 eV, which is much lower than that of ZnO NPs (3.15 eV). Interestingly, ZnHCF@PB NPs were efficiently used for the degradation of conventional (i.e., dyes) and emerging contaminants (i.e., parabens) in deionized water and municipal wastewater matrices to mimic industrial wastewater.
Subject(s)
Environmental Pollutants , Nanoparticles , Zinc Oxide , Water , Methylene Blue , Parabens , WastewaterABSTRACT
Intensive efforts have been taken to decrease the over-potentials of solid-state lithium batteries. Lowering the anode-electrolyte interface resistance is an effective method. Compared to simply improving the interface contact, constructing both ionically and electronically conductive phases within the anode demonstrates superior improvement in reducing the interface resistance and promoting electrochemical stability. However, complex preparation procedures are usually involved in the construction of the conductive phases and the loading of metallic lithium. Herein, a composite anode containing metallic lithium and well-dispersed ionically conductive Li3N and electronically conductive components (Fe, Fe3C, and amorphous carbon) shows an effective decrease in lithium stripping/plating over-potentials at high current densities of up to 3 mA cm-2. The unique dual ionically and electronically conductive phases exhibit good cycling stability for 3000 h. A full battery with the composite anode and a LiFePO4 cathode also demonstrates decent performance. This work confirms the importance of constructing dual conductive phases that are electrochemically stable to Li and will not be consumed during the electrochemical reaction and provides a facile preparation method. The new knowledge discovered and the new methods developed in this work would inspire the future development of new Li-containing composite anodes.
