The lithiation/delithiation properties of α-Si N and β-Si N are compared and the carbon coating effects are examined. Then, β-Si N at various fractions is used as the secondary phase in a Si anode to modify the electrode properties. The incorporated β-Si N decreases the crystal size of Si and introduces a new NSiO species at the β-Si N /Si interface.
View Article and Find Full Text PDFSolid-state lithium-metal batteries have great potential to simultaneously achieve high safety and high energy density for energy storage. However, the low ionic conductivity of the solid electrolyte and large electrode/electrolyte interfacial impedance are bottlenecks. A composite solid electrolyte (CSE) that integrates electrospun LiLaTiO (LLTO) nanofibers, poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) is fabricated in this work.
View Article and Find Full Text PDFACS Appl Mater Interfaces
November 2019
Electrolyte is a key component in high-voltage lithium-ion batteries (LIBs). Bis(trifluoromethanesulfonyl)imide-based ionic liquid (IL)/organic carbonate hybrid electrolytes have been a research focus owing to their excellent balance of safety and ionic conductivity. Nevertheless, corrosion of Al current collectors at high potentials usually happens for this kind of electrolyte.
View Article and Find Full Text PDFTo realize the sustainability of Na-ion batteries (NIBs) for large-scale energy storage applications, a resource-abundant and cost-effective anode material is required. In this study, sugarcane bagasse (SB), one of the most abundant types of biowaste, is chosen as the carbon precursor to produce a hard carbon (HC) anode for NIBs. SB has a great balance of cellulose, hemicellulose, and lignin, which prevents full graphitization of the pyrolyzed carbon but ensures a sufficiently ordered carbon structure for Na transport.
View Article and Find Full Text PDFSnO @CMK-8 composite, a highly promising anode for Na-ion batteries (NIBs), was incorporated with polyvinylidene difluoride (PVDF), sodium carboxymethylcellulose (NaCMC), sodium polyacrylate (NaPAA), and NaCMC/NaPAA mixed binders to optimize the electrode sodiation/desodiation properties. Synergistic effects between NaCMC and NaPAA led to the formation of an effective protective film on the electrode. This coating layer not only increased the charge-discharge Coulombic efficiency, suppressing the accumulation of solid-electrolyte interphases, but also kept the SnO nanoparticles in the CMK-8 matrix, preventing the agglomeration and removal of oxide upon cycling.
View Article and Find Full Text PDFNanosized SnO particles (∼2 nm in diameter) are embedded in ordered mesoporous CMK-8 carbon with unique three-dimensional interconnected pore channels and used as a sodium-ion battery (NIB) anode. Due to the CMK-8 confinement effects, the growth of SnO is suppressed during synthesis, leading to high material electroactivity. The CMK-8 not only serves as an electronic conducting pathway, but also creates interpenetrating tunnels, which guarantee electrolyte accessibility and thus Na transport throughout the electrode.
View Article and Find Full Text PDFWell-ordered periodic mesoporous organosilicas (PMOs) functionalized with high contents of carboxylic acid (COOH) groups, up to 85 mol % based on silica, were synthesized by co-condensation of 1,2-bis(triethoxysilyl)ethane (BTEE) and carboxyethylsilanetriol sodium salt (CES) under acidic conditions by using alkyl poly(oxyethylene) surfactant Brij 76 as a structure-directing agent. A variety of techniques including powder X-ray diffraction (XRD), nitrogen adsorption/desorption, Fourier-transformed infrared (FTIR), transmission electron microscopy (TEM), (13) C- and (29) Si solid-state nuclear magnetic resonance (NMR) were used to characterize the products. The materials thus obtained were used as an effective support to synthesize metal nanoparticles (Ag and Pt) within the channel of 2D hexagonal mesostructure of PMOs.
View Article and Find Full Text PDF