Self-sufficient metal-air battery systems enabled by solid-ion conductive interphases.

Metal-air batteries including Li-air, Na-air, Al-air, and Zn-air, have received significant scientific and technological interest for at least the last three decades. The interest stems primarily from the fact that the electrochemically active material (O2) in the cathode can in principle be harvested from the surroundings. In practice, however, parasitic reactions with reactive components other than oxygen in dry air passivate the anode, limit cycling stability of air-sensitive (e.g., Li, Na, Al) and electrolyte-sensitive (e.g., Zn) anodes, in most cases obviating the energy-density benefits of harvesting O2 from ambient air. As a compromise, so-called metal-oxygen batteries in which pure O2 is used as the active cathode material have been extensively studied but are understood to be of little practical relevance because of the large infrastructure required to produce the pure O2 stream. Here, we report on the design of solid-ion conductive chemically inert metal interphases that simultaneously protect a metal anode from parasitic reactions with electrolyte components and which facilitate rapid interfacial ion transport. Interphases composed of indium (In) are reported to be of particular interest for protecting Li and Na anodes from passivation in air whereas interphases composed of Sn are shown to prevent chemical and electrochemical corrosion of Zn anodes in alkaline electrolytes. We report further that these protections enable so-called self-sufficient metal-air batteries capable of extended cycling stability in ambient air environments.

Microbiota and mycobiota in bronchoalveolar lavage fluid of silicosis patients.

BACKGROUND: The contribution of bronchoalveolar lavage fluid (BALF) microbiota and mycobiota to silicosis has recently been noticed. However, many confounding factors can influence the accuracy of BALF microbiota and mycobiota studies, resulting in inconsistencies in the published results. In this cross-sectional study, we systematically investigated the effects of "sampling in different rounds of BALF" on its microbiota and mycobiota. We further explored the relationship between silicosis fatigue and the microbiota and mycobiota. METHODS: After obtaining approval from the ethics board, we collected 100 BALF samples from 10 patients with silicosis. Demographic data, clinical information, and blood test results were also collected from each patient. The characteristics of the microbiota and mycobiota were defined using next-generation sequencing. However, no non-silicosis referent group was examined, which was a major limitation of this study. RESULTS: Our analysis indicated that subsampling from different rounds of BALF did not affect the alpha- and beta-diversities of microbial and fungal communities when the centrifuged BALF sediment was sufficient for DNA extraction. In contrast, fatigue status significantly influenced the beta-diversity of microbes and fungi (Principal Coordinates Analysis, P = 0.001; P = 0.002). The abundance of Vibrio alone could distinguish silicosis patients with fatigue from those without fatigue (area under the curve = 0.938, 95% confidence interval [CI] 0.870-1.000). Significant correlations were found between Vibrio and haemoglobin levels (P < 0.001, ρ = -0.64). CONCLUSIONS: Sampling in different rounds of BALF showed minimal effect on BALF microbial and fungal diversities; the first round of BALF collection was recommended for microbial and fungal analyses for convenience. In addition, Vibrio may be a potential biomarker for silicosis fatigue screening.

Lithium Iron Phosphate Enhances the Performance of High-Areal-Capacity Sulfur Composite Cathodes.

Lithium iron phosphate (LiFePO4, "LFP") was investigated as an additive in the cathode of lithium-sulfur (Li-S) batteries. LFP addition boosted the sulfur utilization during Li-S cycling, achieving an initial capacity of 1465 mAh/gS and a long cycle life (>300 cycles). Polysulfide adsorption experiments showed that LFP attracted polysulfides, and thus, the presence of LFP should alleviate the shuttle effect, a common failure mode. Postmortem characterization found iron phosphides, iron phosphates, and LiF in the electrode, indicating that LFP underwent dynamic reconstruction during Li-S cycling. We suspect that the formation of these species played a role in the observed performance. From the processing standpoint, adding LFP improved slurry rheology, making the preparation of a high-loading electrode more consistent. Benefiting from the high sulfur utilization and the ability to prepare electrodes with high mass loading, the S-LFP hybrid cell showed an excellent areal capacity of 2.65 mAh/cm2 and could be stably cycled at 2 mAh/cm2 for 250 cycles. Our results demonstrated the LFP addition as a promising strategy for realizing Li-S batteries with high sulfur loading and areal capacity.

Designing interphases for practical aqueous zinc flow batteries with high power density and high areal capacity.

Aqueous zinc flow batteries (AZFBs) with high power density and high areal capacity are attractive, both in terms of cost and safety. A number of fundamental challenges associated with out-of-plane growth and undesirable side reactions on the anode side, as well as sluggish reaction kinetics and active material loss on the cathode side, limit practical deployment of these batteries. We investigated artificial interphases created using a simple electrospray methodology as a strategy for addressing each of these challenges. The effectiveness of the electrospray interphases in full cell zinc-iodine flow batteries was evaluated and reported; it is possible to simultaneously achieve high power density [115 milliwatts per square centimeter (mW/cm2)] and high areal capacity [25 milliampere hour per square centimeter (mA·hour/cm2)]. Last, we extended it to aqueous zinc-bromine and zinc-vanadium flow batteries of contemporary interest. It is again found that high power density (255 and 260 mW/cm2, respectively) and high areal capacity (20 mA·hour/cm2) can be simultaneously achieved in AZFBs.

Production of fast-charge Zn-based aqueous batteries via interfacial adsorption of ion-oligomer complexes.

Aqueous zinc batteries are attracting interest because of their potential for cost-effective and safe electricity storage. However, metallic zinc exhibits only moderate reversibility in aqueous electrolytes. To circumvent this issue, we study aqueous Zn batteries able to form nanometric interphases at the Zn metal/liquid electrolyte interface, composed of an ion-oligomer complex. In Zn||Zn symmetric cell studies, we report highly reversible cycling at high current densities and capacities (e.g., 160 mA cm-2; 2.6 mAh cm-2). By means of quartz-crystal microbalance, nuclear magnetic resonance, and voltammetry measurements we show that the interphase film exists in a dynamic equilibrium with oligomers dissolved in the electrolyte. The interphase strategy is applied to aqueous Zn||I2 and Zn||MnO2 cells that are charged/discharged for 12,000 cycles and 1000 cycles, respectively, at a current density of 160 mA cm-2 and capacity of approximately 0.85 mAh cm-2. Finally, we demonstrate that Zn||I2-carbon pouch cells (9 cm2 area) cycle stably and deliver a specific energy of 151 Wh/kg (based on the total mass of active materials in the electrode) at a charge current density of 56 mA cm-2.

Bronchoalveolar Lavage Fluid microRNA-146a: A Biomarker of Disease Severity and Pulmonary Function in Patients With Silicosis.

OBJECTIVE: To examine the impact of microRNA-146a (miR-146a) on pulmonary function and disease severity in silicosis patients. METHODS: Twenty-nine silicosis patients and six observation subjects were recruited. MiR-146a expression level was detected by qRT-PCR, and pulmonary function was assessed with a spirometer. RESULTS: MiR-146a expression level was higher in silicosis patients than in observation subjects, and the probability of suffering from silicosis increased with increasing miR-146a level. MiR-146a was associated with the severity of silicosis. As the miR-146a increased, the probability of suffering from silicosis increased for stage I patients, and for stage II & III patients, the probability first increased and then decreased. MiR-146a was also associated with decreased pulmonary function measures, pulmonary function impairment, and restrictive ventilator dysfunction. CONCLUSIONS: miR-146a was significantly associated with the disease severity and pulmonary function of silicosis.

Genome-wide analysis of aberrantly expressed microRNAs in bronchoalveolar lavage fluid from patients with silicosis.

Background To identify differentially expressed miRNAs profiles in bronchoalveolar lavage fluid (BALF) from patients with silicosis and consider the potential contribution of miRNAs to silicosis.Methods miRNAs expression profiling were performed in the cell fraction of BALF samples obtained from 9 subjects (3 silicosis observation subjects, 3 stage I and stage II silicosis patients, respectively). The differential expression of two selected miRNAs hsa-miR-181c-5p and hsa-miR-29a-3p were confirmed by RT-qPCR. Furthermore, miRNAs Gene Ontology Enrichment categories and target mRNAs were determined based on miRWalk.Results We found 110 dysregulated miRNAs in silicosis samples, most of which showed a down-regulation trend. Microarray results were confirmed by RT-qPCR. With the observation group samples set as standards, stage I samples showed 123 differentially expressed miRNAs, and stage II 46. 23 miRNAs were dysregulated in both stages. Finally, functional enrichment analysis indicated that these miRNAs played an important role in various biological processes, including ECM-receptor interaction and endocytosis.Conclusions This is the first time to acquire the BALF-derived microRNAs expression profiling targeting to human silicosis. These results contribute to unravelling miRNAs involved in the pathogenesis of silicosis, and provide new tools of potential use of as biomarkers for diagnosis and/or therapeutic purposes.