Batteries play an increasingly critical role in the functioning of contemporary society. To ensure future proofing of battery technology, new materials and methods that overcome the current shortcomings need to be developed. Here we report the use of the inexpensive and off the shelf metal-carboxylate, copper tartrate, as a high-capacity anode material for lithium-ion batteries, providing a specific capacity of 744 mA h g-1 when cycled at 50 mA g-1. Additionally, an unusual capacity gain with cycling is investigated using advanced techniques including X-ray absorption spectroscopy (XAS), X-ray diffraction (XRD), and small and ultra-small angle neutron scattering (SANS and USANS), providing insight into the structure-performance relationship of the electrode. Subsequently, a novel method of in situ generation of the active material is demonstrated using the reaction between the parent acid, tartaric acid, and the copper current collector during electrode formulation. This serves to increase and stabilise the electrode performance, as well as to make use of a cheaper feedstock (tartaric acid), and reduce some of the "dead mass" of the copper current collector.
New materials for battery electrodes are paramount to ensuring future battery supply can meet the ever-increasing demand for energy storage. Furthermore, detailed investigation on the various physical and chemical aspects of these materials is required to allow the same level of nuanced microstructural and electrochemical tuning that is available for conventional electrode materials. Here a comprehensive investigation is undertaken on the poorly understood in situ reaction between dicarboxylic acids and the copper current collector that occurs during electrode formulation, using a series of simple dicarboxylic acids. Specifically, we focus on the relationship between the extent of the reaction and the properties of the acid. Additionally, the extent of the reaction was demonstrated to affect both the electrode microstructure and the electrochemical performance. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and small and ultra-small angle neutron scattering (U/SANS) are used to provide unprecedented detail on the microstructure ultimately leading to a deeper understanding of formulation based performance enhancing techniques. Ultimately, it was determined that the copper-carboxylates are the active material, not the parent acid, and in some cases i.e., copper malate, capacities as high as 828 mA h g-1 were achieved. This work lays the foundation for future studies that use the current collector as an "active" component in electrode formulation and function rather than simply an inactive component of a battery.
The established cytotoxic agent RITA contains a thiophene-furan-thiophene backbone and two terminal alcohol groups. Herein we investigate the effect of using thiazoles as the backbone in RITA-like molecules and modifying the terminal groups of these trithiazoles, thereby generating 41 unique structures. Incorporating side chains with varied steric bulk allowed us to investigate how size and a stereocenter impacted biological activity. Subjecting compounds to growth inhibition assays on HCT-116 cells showed that the most potent compounds 7d, 7e, and 7h had GI50 values of 4.4, 4.4, and 3.4 µM, respectively, versus RITA (GI50 of 800 nM). Analysis of these compounds in apoptosis assays proved that 7d, 7e, and 7h were as effective as RITA at inducing apoptosis. Evaluating the impact of 7h on proteins targeted by RITA (p53, c-Myc, and Mcl-1) indicated that it acts via a different mechanism of action to that of RITA. RITA suppressed Mcl-1 protein via p53, whereas compound 7h suppressed Mcl-1 expression via an alternative mechanism independent of p53.
We report photochromic donor-acceptor Stenhouse adducts (DASAs) capable of fully reversible photoisomerization with visible light in organic solvents including chloroform, acetonitrile and benzene. The rates of photoisomerization and thermal reversion can be tuned by altering the electronics of the donor adduct. X-Ray crystallography and photo-NMR experiments unambiguously establish molecular structures.
