Cell Chemistry of Sodium–Oxygen Batteries with Various Nonaqueous Electrolytes

Development of the nonaqueous Na–O₂ battery with a high electrical energy efficiency requires the electrolyte stable against attack of highly oxidative species such as nucleophilic anion O₂^•–. A combined evaluation method was used to investigate the Na–O₂ cell chemistry with various solvents, including ethylene carbonate/propylene carbonate (EC/PC)-, <i>N</i>-methyl-<i>N</i>-propylpiperidinium bis­(trifluoromethansulfonyl) imide (PP13TFSI)-, and tetraethylene glycol dimethyl ether (TEGDME)-based electrolytes. It is found that the TEGDME-based electrolytes have the best stability with the predominant yield of NaO₂ upon discharge and the largest electrical energy efficiency (approaching 90%). Both EC/PC- and PP13TFSI-based electrolytes severely decompose during discharge, forming a large amount of side products. Analysis of the acid dissociation constant (p<i>K</i>_a) of these electrolyte solvents reveals that the TEGDME has the relatively large value of p<i>K</i>_a, which correlates with good stability of the electrolyte and high round-trip energy efficiency of the battery

Rationally Turning the Interface Activity of Mesoporous Silicas for Preparing Pickering Foam and “Dry Water”

We develop a novel protocol to prepare smart, gas/water interface-active, mesoporous silica particles. This protocol involves modification of highly mesoporous silicas with a mixture of hydrophobic octyl organosilane and hydrophilic triamine organosilane. Their structure and compositions are characterized by transmission electron microscopy (TEM), N₂ sorption, solid state NMR, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectra (FT-IR), thermogravimetric analysis (TGA), and elemental analysis. It is demonstrated that our protocol enables the interface activity of mesoporous silica particles to be facilely tuned, so that the stable gas–water interfaces ranging from air bubbles dispersed in water (Pickering foam) and water droplets dispersed in air (“dry water”) can be achieved, depending on the molar ratio of these two organosilanes. The “dry water” is not otherwise attainable for the analogous nonporous silica particles, indicting the uniqueness of the chosen mesoporous structures. Moreover, these particle-stabilized Pickering foams and “dry waters” can be disassembled in response to pH. Interestingly, it was found that aqueous potassium carbonate droplets stabilized by these interface-active mesoporous silica particles (“dry K₂CO₃-containing water”) could automatically capture CO₂ from a simulated flue gas with enhanced adsorption rate and adsorption capacity when compared to the aqueous potassium carbonate bulk solution. This study not only supplies a novel type of efficient, smart, gas/water interface-active mesoporous silica particles but also demonstrates an innovative application of mesoporous materials in gas adsorption

Alignment of the predicted amino acid sequences of <i>Tomicus yunnanensis</i> sHSPs. The conserved α-crystallin domain is underlined.

<p>Identical residues are shaded black, conserved substitutions are shaded grey. Dash (–) indicates insertion or deletion.</p

Length distribution of unigenes.

<p>The number of y-axis has been transfer into logarithmic scale.</p

Alignment of the partial amino acid sequence of <i>Tomicus yunnanensis</i> HSP60 with that of other insects.

<p>(A) the ATP-binding motif. (B) The classical mt-HSP60 signature (underlined) motif. Identical amino acids are shaded black, and conserved residues are shaded grey. Tca, <i>Tribolium castaneum</i> (XP_971630), Ame, <i>Apis mellifera</i> (XP_392899), Csu, <i>Chilo suppressalis</i> (ACT52824); Lsa, <i>Liriomyza sativae</i> (AAW49251).</p

Characteristics of homology search of Illumina sequences against the nr database.

<p>(A) E-value distribution of BLAST hits for each unique sequence with a cut-off E-value of 1.0E-5. (B) Species distribution of the BLASTX results. We used the first hit of each sequence for analysis.</p

Putative genes of interest related to insecticide resistance.

<p>Putative genes of interest related to insecticide resistance.</p

Sequence statistics of the Illumina sequencing assembly.

<p>Sequence statistics of the Illumina sequencing assembly.</p

Alignment of the <i>Tomicus yunnanensis</i> HSP40 amino acid sequence with other insects HSP40 amino acid sequences.

<p>The conserved J domain is underlined. The Gly/Phe-rich domain is double underlined. The cysteine-rich domain is indicated as dotted line. Identical residues are shaded black, conserved substitutions are shaded grey. Dash (–) indicates insertion or deletion. Tca, <i>Tribolium castaneum</i> (EFA11191); Lsa, <i>Liriomyza sativae</i> (ABE57132); Lmi, <i>Locusta migratoria</i> (ABC84495); Bmo, <i>Bombyx mori</i> (BAD90846).</p

Putatively identified GST genes in <i>Tomicus yunnanensis</i>.

<p>Putatively identified GST genes in <i>Tomicus yunnanensis</i>.</p