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[en] Highlights: ► P(VDF-HFP)/SBA-15 nanocomposite membranes in DSSCs was prepared by a solution casting method. ► The ionic conductivity of the P(VDF-HFP) electrolyte membranes were improved by addition of an optimal quantity of I-SBA-15 fillers, because the mesoporous SBA-15 fillers act as a micro-electrolyte reservoir, trapping DMPII within its mesoporous stricture. ► DSSC devices based on P(VDF-HFP)/I-SBA-15 nanocomposite membrane produced the highest conversion efficiency of ca. 5.29%, while illuminated at 100 mW cm−2. - Abstract: Poly(vinylidenefluoride-co-hexafluoropropylene)/SBA-15 molecular sieves (designated as P(VDF-HFP)/SBA-15) nanocomposite membranes were prepared by a solution casting method. Prior to blending, the SBA-15 molecular sieves were impregnated with dimethylpropylimidazolium iodide (DMPII) ionic liquid. The P(VDF-HFP)/SBA-15 nanocomposite membranes were characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and AC impedance spectroscopy. The room temperature ionic conductivity of the P(VDF-HFP)/SBA-15A nanocomposite polymer electrolyte was of the order of around 10−3 S cm−1. The quasi-solid-state dye-sensitized solar cells (DSSCs) were assembled by using photo-electrodes of TiO2 films on FTO/glass and the counter electrode based on the pulsed-plated Pt films. P(VDF-HFP)/I-SBA-15 nanocomposite electrolyte membrane containing dimethylpropylimidazolium iodide (DMPII) provides the best energy conversion efficiency of ca. 5.29%. This result indicates that the P(VDF-HFP)/I-SBA-15 nanocomposite membrane is a good candidate for a quasi-solid-state DSSC applications.
[en] Graphical abstract: - Highlights: • The work reports the preparation of a V-doped Li4Ti5O12/C anode material by a solid-state method. • LiFe0.5Mn0.5PO4/C cathode material was also prepared by a ball-milled solid state method. • Li4Ti4.90V0.10O12/C cell achieves the specific capacities of 132 and 110 mAh g−1 at 1C/1C and 20C/20C rate, respectively. • Li4Ti5O12/LiFe0.5Mn0.5PO4 full cell exhibits excellent performance with the discharge capacity of 161 mAh g−1 at 0.2 C. - Abstract: In this study, a V-doped Li4Ti5O12/C (LTO/C) anode material is prepared using a solid-state method. Furan resin and vanadium are employed to metal dope and carbon coat LTO, respectively. To prepare LiFe0.5Mn0.5PO4/C (LFMP/C) cathode materials, a ball-milling method is used to induce a solid-state reaction by using polystyrene and citric acid as a carbon source and complexing agent, respectively. The characteristic properties of the samples are examined using X-ray diffraction (XRD), micro-Raman spectroscopy, scanning electron microscopy (SEM), and the AC impedance and galvanostatic charge–discharge methods. Finally, an LTO/LFMP full cell is constructed and examined. The full cell exhibited discharge capacities of 161, 152, 141, 123, 111, and 84 mAh g−1 at 0.2, 0.5, 1, 3, 5, and 10 C, respectively, showing that both the Li4Ti4.95V0.05O12/C anode and LFMP/C cathode are potential candidates for application in high-power Li-ion batteries
[en] Graphical abstract: - Highlights: • PVDF-HFP/SBA15 membrane and NCM cathode material were prepared for Li ion battery. • SBA15 fillers can trap more liquid electrolytes to enhance the ionic conductivity. • Modified fillers with functional groups play a key role in reducing impedance. • LiNi_0_._5Co_0_._2Mn_0_._3O_2 polymer battery showed excellent electrochemical performance. - Abstract: This study reports the preparation of a composite polymer electrolyte for application in LiNi_0_._5Co_0_._2Mn_0_._3O_2 lithium-polymer batteries. Poly(vinylidiene fluoride-hexafluoropropylene) (denoted as PVDF-HFP) was used as the polymer host and mesoporous modified-silica fillers (denoted as m-SBA15) used as the solid plasticizer were added into the polymer matrix. The characteristic properties of the composite polymer membranes were examined using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), and an AC impedance method. The discharge capacities of LiNi_0_._5Co_0_._2Mn_0_._3O_2 polymer batteries with a PE separator, pure PVDF-HFP polymer membrane, or a PVDF-HFP/10 wt.%m-SBA15 composite at 0.1 C were determined to be 155.5, 159.5, and 198.6 mAh g"−"1, respectively. The LiNi_0_._5Co_0_._2Mn_0_._3O_2 polymer battery containing the PVDF-HFP/10 wt.%m-SBA15 composite achieved discharge capacities of 194, 170, 161, 150, 129, 115, and 87 mAh g"−"1 at 0.1, 0.2, 0.5, 1, 3, 5, and 10 C, respectively. The lithium-polymer battery demonstrated a high coulomb efficiency of ca. 99%. The PVDF-HFP/m-SBA15 composite membrane is a strong candidate for application in LiNi_0_._5Co_0_._2Mn_0_._3O_2 lithium-polymer batteries
[en] Highlights: • The LiFePO4/porous graphene oxide/C was prepared by a hydrothermal method and a spray dry process. • The porous graphene oxide was prepared through an activation method. • The discharge capacity of the SP-LFP/1%PGO/C is 107 mAh g−1 after 1000 cycles at 10C rate. • The SP-LFP/PGO/C material shows promising candidate for high-power Li-ion battery in EV. - Abstract: A 3D spray-dried micro/mesoporous LiFePO4/porous graphene oxide/C (denoted as SP-LFP/PGO/C) composite material is synthesized via a three-step process, i.e., hydrothermal process, carbon coating, and spray dry method in sequence. The 2D porous graphene oxide (denoted as PGO) material is first prepared through an activation method. The galvanostatic charge-discharge measurements of LFP composites without graphene oxide, with 1 wt% graphene oxide, and 1 wt% PGO are conducted in the potential range of 2–3.8 V at various rates (0.1–10C). It is revealed that the SP-LFP/PGO/C material shows the best performance among three samples. The discharge capacities of the SP-LFP/PGO/C composites are observed to 160, 152, 151, 149, 144, 139, 127 mAh g−1 at 0.1C, 0.2C, 0.5C, 1C, 3C, 5C and 10C rate. In particular, the discharge capacity of the SP-LFP/PGO/C composite with 1 wt% PGO is 107 mAh g−1 after 1000 cycles at a 10C rate, and its capacity retention is ca. 97%. It is due to the unique structural and geometrical feature of SP-LFP/PGO/C composite, there the diamond-like (rhombus) LFP nanoparticles are embedded in porous GO matrix which forming a porous three-dimensional network for fast electronic and ionic transport channels.