Relationship between Silicon Percentage in Graphite Anode to Achieve High-Energy-Density Lithium-Ion Batteries.

High-weight-percentage silicon (Si) in graphite (Gr) anodes face commercialization hurdles due to fundamental and interrelated challenges. Nevertheless, using the existing manufacturing line, the optimized Si/Gr ratio is the most efficient and valuable way to fabricate high-energy-density lithium-ion batteries (LIBs). Still, literature has not thoroughly examined the Si/Gr ratio. This study addresses this critical gap by systematically evaluating Si content (5-20 wt %) in commercial graphite. The goal is to optimize the Si/Gr ratio for exceptional specific capacity while mitigating inherent Si limitations like cyclic stability and first-cycle irreversible capacity loss. This work employs a multidirectional approach, including in situ electrochemical impedance spectroscopy for interface analysis, rate capability assessment (up to 3 C-rate), Li diffusion coefficient measurement, and thorough cyclic stability evaluation. Increasing the silicon (Si) weight percent from 10% to 15% in the Si15Gr75 composite anode resulted in significant improvements in the first lithiation and delithiation capacities by approximately 16.8% and 16.0%, respectively. The Si15Gr75 cell delivered a high initial Coulombic efficiency of roughly 82.9%, nearly equivalent to a pure graphite anode. Furthermore, the Si15Gr75 Li cell exhibited excellent cyclic stability at a current rate of 0.5 C, retaining about 60% of its capacity after 215 cycles. Additionally, full-cell testing against a commercial NMC622 cathode showcases excellent performance across various current rates (0.1-0.5 C). This study paves the way for the development of high-energy-density LIBs by providing valuable insights into the optimization of Si/Gr composite anodes for commercial viability.

Automated Generation of hiPSC-Derived Hepatic Progeny by Cost-Efficient Compounds.

Human pluripotent stem cell (hPSC)-derived hepatocyte-like cells (HLCs) hold great promise for liver disease modeling, drug discovery, and drug toxicity screens. Yet, several hurdles still need to be overcome, including among others decrease in the cost of goods to generate HLCs and automation of the differentiation process. We here describe that the use of an automated liquid handling system results in highly reproducible HLC differentiation from hPSCs. This enabled us to screen 92 chemicals to replace expensive growth factors at each step of the differentiation protocol to reduce the cost of goods of the differentiation protocol by approximately 79%. In addition, we also evaluated several recombinant extracellular matrices to replace Matrigel. We demonstrated that differentiation of hPSCs on Laminin-521 using an optimized small molecule combination resulted in HLCs that were transcriptionally identical to HLCs generated using the growth factor combinations. In addition, the HLCs created using the optimized small molecule combination secreted similar amounts of albumin and urea, and relatively low concentrations of alfa-fetoprotein, displayed similar CYP3A4 functionality, and a similar drug toxicity susceptibility as HLCs generated with growth factor cocktails. The broad applicability of the new differentiation protocol was demonstrated for 4 different hPSC lines. This allowed the creation of a scalable, xeno-free, and cost-efficient hPSC-derived HLC culture, suitable for high throughput disease modeling and drug screenings, or even for the creation of HLCs for regenerative therapies.

Germanium-Free Dense Lithium Superionic Conductor and Interface Re-Engineering for All-Solid-State Lithium Batteries against High-Voltage Cathode.

Li10GeP2S12 (LGPS) solid electrolyte is not affordable due to the high cost of Ge metal, making it economically unviable despite being a lithium superionic conductor. The synthesis of such solid electrolytes is much more time- and energy-consuming and needs an inert environment. Here, we report Si (silicon)-based composition [Li10SiP2S12 (LSiPS)] to make it cost-effective through microwave heating (MW). The total time for synthesis processes, including ball milling, heating rate, and heating dwell time, is ∼120 min, much less than the previous reports. We have also avoided vacuum sealing/Ar-purging to reduce the synthesis cost further. During MW heating, the densification process dominates over coarsening, resulting in a dense nanoflake morphology with a finer crystallite size. The synthesized LSiPS has a high fraction (∼89%) of more conducting tetragonal phase as identified by NMR analysis. Further, we modified the interface between the Li anode and LSiPS by forming a lithiophobic and lithiophilic kind of gradient interlayer to reduce the reduction of LSiPS and suppress the side reactions. The interface modification resulted in a better Li/LSiPS/Li cyclic performance for 1800 h at 0.2 mA/cm2 and 500 h at 1.0 mA/cm2. All-solid-state lithium-metal batteries (ASSLIB) have been developed against a high-voltage cathode (LCMO-coated LCO) and showed an excellent cycling performance with a reversible capacity of ∼110 mAh/g after 300 cycles.

Regulating Polysulfide Conversion Kinetics Using Tungsten Diboride as Additive For High-Performance Li-S Battery.

The practical application of Li-S batteries is severely limited due to low sulfur utilization, sluggish sulfur redox kinetics, intermediate polysulfide dissolution/shuttling, and subsequent anode degradation. A smart cathode with efficient electrocatalyst and a protected anode is necessary. Herein, hollow carbon (HC) spheres are used as a sulfur host to improve the electrical conductivity and buffer the volume expansion of active materials. Considering the weak interaction between carbon and lithium polysulfides (LiPS), tungsten diboride (WB2 ) nanoparticles are used as a conductive additive. Both experimental and density functional theory (DFT) comprehensively exhibit that metallic WB2 nanoparticles can firmly anchor the LiPS through B-S bond formation, accelerate their electrocatalytic conversion, and immobilize them. DFT also reveals that boron interacts with LiPS either through molecular or dissociative adsorption depending on its boron layer arrangement in WB2 . Further, a freestanding lithiated-poly(4-styrene sulfonate) membrane constructed on lithium, offers a homogeneous Li-ion flux, stable interface, and protection from LiPS. Finally, cells with the HC-S+WB2  cathode and protected anode exhibit improved active material utilization, superior rate performance, and impressive cycling stability, even at high sulfur loading and less quantity of the electrolyte. Further, the pouch cells demonstrate high reversible capacity and an excellent capacity retention.

Artificial Organo-Fluoro-Rich Anode Electrolyte Interface and Partially Sodiated Hard Carbon Anode for Improved Cycle Life and Practical Sodium-Ion Batteries.

In this work, a strategy is introduced wherein without keeping any excess cathode, a practical full-cell sodium-ion battery has been demonstrated by utilizing a hard carbon (HC) anode and sodium vanadium fluorophosphate and carbon nanotube composite (NVPF@C@CNT) cathode. A thin, robust, and durable solid electrolyte interface (SEI) is created on the surface of HC through its incubation wetted with a fluoroethylene carbonate (FEC)-rich warm electrolyte in direct contact with Na metal. During the incubation, the HC anode is partially sodiated and passivated with a thin SEI layer. The sodium-ion full cell fabricated while maintaining N/P ∼1.1 showed the first cycle Coulombic efficiency of ∼97% and delivered a stable areal capacity of 1.4 mAh cm-2 at a current rate of 0.1 mA cm-2 realized for the first time to the best of our knowledge. The full cell also showed a good rate capability, retaining 1.18 mAh cm-2 of its initial capacity even at a high current rate of 0.5 mA cm-2, and excellent cycling stability, giving a capacity of ∼1.0 mAh cm-2 after 500 cycles. The current strategy presents a practical way to make a sodium-ion full cell, utilizing no excess cathode material, significantly saving cost and time.

Direct-Contact Prelithiation of Si-C Anode Study as a Function of Time, Pressure, Temperature, and the Cell Ideal Time.

Direct-contact prelithiation (PL) is a facile, practical, and scalable method to overcome the first-cycle loss and large volume expansion issues for silicon anode (with 30 wt % Si loading) material, and a detailed study is absent. Here, an understanding of direct-contact PL as a function of the PL time, and the effects of externally applied pressure (weight), microstructure, and operating temperature have been studied. The impact of PL on the Si-C electrode surfaces has been analyzed by electrochemical techniques and different microstructural analyses. The solid electrolyte interface (SEI) layer thickness increases with the increase in PL time and decreases after 2 min of PL time. The ideal PL time was found to be between 15 (PL-15) and 30 (PL-30) min with 83.5 and 97.3% initial Coulombic efficiency (ICE), respectively, for 20 g of externally applied weight. The PL-15 and PL-30 cells showed better cyclic stability than PL-0 (without prelithiation), with more than 90% capacity retention after 500 cycles at 1 A g-1 current density. The discharge capacities for PL-15 and PL-30 have been observed as highest at 45 °C operating temperature with limited cyclability. We propose here a synchronization strategy in prelithiation time, pressure, and temperature to achieve excellent cell performance.

Cocrystal of 5-Fluorouracil: Characterization and Evaluation of Biopharmaceutical Parameters.

To prepare the cocrystals of 5-fluorouracil (5-FU) with GRAS status coformers via a cocrystallization technique with an aim to improve physicochemical properties as well as bioavailability for colon cancer, breast cancer, and prostate cancer. The mechanochemical method was used in the preparations of three crystals of 5-FU with gentisic acid (5-FUGA), 3,4-dihydroxybenzoic acid (5-FUBA), and 4-aminopyridine (5-FUPN). A thermoanalytical and spectroscopic technique was used for their characterization. Their biological evaluation was done in different cancer cell lines. The new solid pure crystal forms were characterized by DSC, FTIR, and PXRD. The crystal structure was determined from single crystal and PXRD that exposed the existence of the monoclinic and triclinic crystal system with P21/n and P-1 space groups. The dermatokinetic studies on the rat skin revealed two- to threefold improvement in relative bioavailability as compared to pure 5-FU. "MTT assay was performed by varying the concentrations of the drug from 1 to 50 µg mL-1. After 24 h, the cell viability dropped to 70.67%, 74.05%, and 76.37% in MCF-7, Hela, and Caco-2 cell lines when the concentration of 5-FU was 50 µg mL-1", while it dropped dramatically in cocrystals 5-FUGA (22.06%, 24.63%, and 25.61%), 5-FUBA (31.22%, 29.46%, and 32.81%), and 5-FUPN (21.65%, 32.64%, and 21.46%). All the results indicated that 5-FU cocrystals possess better antitumor efficacy than free drug. Thus, cocrystallization expands the extent of the existing pre-formulation options ahead of pure API form to ameliorate the bioavailability and permeability.

Oral dosing of pentoxifylline, a pan-phosphodiesterase inhibitor restores bone mass and quality in osteopenic rabbits by an osteogenic mechanism: A comparative study with human parathyroid hormone.

The non-selective phosphodiesterase inhibitor pentoxifylline (PTX) is used for the treatment of intermittent claudication due to artery occlusion. Previous studies in rodents have reported salutary effects of the intraperitoneal administration of PTX in segmental bone defect and fracture healing, as well as stimulation of bone formation. We determined the effect of orally dosed PTX in skeletally mature ovariectomized (OVX) rabbits with osteopenia. The half-maximal effective concentration (EC50) of PTX in rabbit bone marrow stromal cells was 3.07 ±â€¯1.37 nM. The plasma PTX level was 2.05 ±â€¯0.522 nM after a single oral dose of 12.5mg/kg, which was one-sixth of the adult human dose of PTX. Four months of daily oral dosing of PTX at 12.5 mg/kg to osteopenic rabbits completely restored bone mineral density, bone mineral content (BMC), microarchitecture and bone strength to the level of the sham-operated (ovary intact) group. The bone strength to BMC relationship between PTX and sham was similar. The bone restorative effect of PTX was observed in both axial and appendicular bones. In osteopenic rabbits, PTX increased serum amino-terminal propeptide, mineralized nodule formation by stromal cells and osteogenic gene expression in bone. PTX reversed decreased calcium weight percentage and poor crystal packing found in osteopenic rabbits. Furthermore, similar to parathyroid hormone (PTH), PTX had no effect on bone resorption. Taken together, our data show that PTX completely restored bone mass, bone strength and bone mineral properties by an anabolic mechanism. PTX has the potential to become an oral osteogenic drug for the treatment of post-menopausal osteoporosis.

Bilateral macular holes in X-linked retinoschisis: now the spectrum is wider.

Bilateral occurrence of macular hole in X-linked retinoschisis is an extremely rare event. Spectral domain optical coherence tomography (OCT) findings revealed that formation of a macular hole is secondary to the retinoschisis process alone. Bilateral macular holes should be added to the spectrum of X-linked retinoschisis variations and the retinoschisis process alone should be accounted for their formation.

Detection of bioconjugated quantum dots passivated with different ligands for bio-applications.

Bioconjugation of quantum dots has resulted in a significant increase in resolution of biological fluorescent labeling. This intrinsic property of quantum dots can be utilized for sensitive detection of target analytes with high sensitivity; including pathogenic bacteria and cancer monitoring. The quantum dots and quantum dot doped silica nanoparticles exhibit prominent emission peaks when excited at 400 nm but on conjugation to model rabbit antigoat antibodies exhibit diminished intensity of emission peak at 600 nm. It shows that photoluminescence intensity of conjugated quantum dots and quantum dot doped silica nanoparticles could permit the detection of bioconjugation. Samples of conjugated and unconjugated quantum dots and quantum dot doped silica nanoparticles were subjected to enzyme linked immunosorbent assay for further confirmation of bioconjugation. In the present study ligand exchange, bioconjugation, fluorescence detection of bioconjugated quantum dots and quantum dot doped silica nanoparticles and further confirmation of bioconjugation by enzyme linked immunosorbent assay has been described.