We are currently in the midst of a race to discover and develop new battery materials capable of providing high energy-density at low cost. By combining a high-performance Si electrode architecture with a room temperature ionic liquid electrolyte, here we demonstrate a highly energy-dense lithium-ion cell with an impressively long cycling life, maintaining over 75% capacity after 500 cycles. Such high performance is enabled by a stable half-cell coulombic efficiency of 99.97%, averaged over the first 200 cycles. Equally as significant, our detailed characterization elucidates the previously convoluted mechanisms of the solid-electrolyte interphase on Si electrodes. We provide a theoretical simulation to model the interface and microstructural-compositional analyses that confirm our theoretical predictions and allow us to visualize the precise location and constitution of various interfacial components. This work provides new science related to the interfacial stability of Si-based materials while granting positive exposure to ionic liquid electrochemistry.

Sequestering carbon dioxide emissions by the trap and release of CO2 via thermally activated chemical reactions has proven problematic because of the energetic requirements of the release reactions. Here we demonstrate trap and release of carbon dioxide using electrochemical activation, where the reactions in both directions are exergonic and proceed rapidly with low activation barriers. One-electron reduction of 4,4'-bipyridine forms the radical anion, which undergoes rapid covalent bond formation with carbon dioxide to form an adduct. One-electron oxidation of this adduct releases the bipyridine and carbon dioxide. Reversible trap and release of carbon dioxide over multiple cycles is demonstrated in solution at room temperature, and without the requirement for thermal activation.

We describe a new electrochemical cycle that enables capture and release of carbon dioxide. The capture agent is benzylthiolate (RS), generated electrochemically by reduction of benzyldisulfide (RSSR). Reaction of RS with CO produces a terminal, sulfur-bound monothiocarbonate, RSCO, which acts as the CO carrier species, much the same as a carbamate serves as the CO carrier for amine-based capture strategies. Oxidation of the thiocarbonate releases CO and regenerates RSSR. The newly reported S-benzylthiocarbonate (IUPAC name benzylsulfanylformate) is characterized by H andC NMR, FTIR, and electrochemical analysis. The capture-release cycle is studied in the ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (BMP TFSI) and dimethylformamide. Quantum chemical calculations give a binding energy of CO to benzyl thiolate of -66.3 kJ mol, consistent with the experimental observation of formation of a stable CO adduct. The data described here represent the first report of electrochemical behavior of a sulfur-bound terminal thiocarbonate.

Objectives-To assess the relationship between quality of hospital care, as measured by ACOVE quality indicators, and post-discharge mortality for hospitalized seniors. Design-Observational cohort study Setting-Single academic medical centerParticipants-Patients age 65 and over who were identified as "vulnerable" using the Vulnerable Elder Survey (VES-13) Measurements-Adherence to 16 ACOVE measures through chart audit; Post-discharge mortality obtained through Social Security Death Index Results-856 inpatient vulnerable elders were enrolled. Mean quality of care score was 59.5% (SD 19.2) and 495 (26.7%) died within one year of discharge. In multivariate logistic regression, controlling for sociodemographic and disease severity variables (Charlson comorbidity score, VES-13 score, number of quality indicators triggered, length of stay, baseline ADL limitations, code status), higher quality of care appeared to be associated with a lower risk of death at one year. For each 10% increase in quality score, patients were 7% less likely to die [OR 0.93 (0.87-1.00), p=0.045]. In Cox proportional hazard models, those hospitalized patients receiving quality of care better than the median quality score were less likely to die 1 year period postdischarge [HR 0.82, 95% CI (0.68-1.00), p=0.05]. Those patients that received a nutritional status assessment were less likely to die one year after discharge [HR 0.61, p=0.022].Conclusion-Higher quality of care for hospitalized seniors, as measured by ACOVE measures, may be associated with a lower likelihood of death 1 year after discharge. Given these findings, future work testing interventions to improve adherence to these quality indicators is warranted.