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A novel method of using anion-functionalized ionic liquids (ILs) with high NO absorption capacity and reversibility for the capture and in situ oxidation of low-concentration NO was established. For the mixed gas containing 0.25% NO, the accumulation rate of nitric acid in these ILs was significantly higher than that in the conventional ILs; after absorption and oxidation reached equilibrium, the molar ratio of HNO₃ to [P₄₄₄₆][PhSO₃] was 0.86, which was 5 times as high as that of the conventional IL. Therefore, the problems of low efficiency and poor reversibility of traditional ILs in the absorption and oxidation process were solved. Through absorption and oxidation experiments, quantum chemical calculation, NMR, and time-resolved in situ ATR-FTIR spectroscopic investigation, the results demonstrated that such a high accumulation rate of HNO₃ originated from high uptake of NO through multiple-site interaction. Moreover, high reversibility is attributed to low volatility of conjugated acid of anions and decreased basicity of O sites on anions. We believe that such highly efficient and reversible conversion of low-concentration NO to HNO₃ by ILs provides a new strategy for improving atomic economy of fossil fuel combustion, that is, converting post-combustion pollutants to good valuable chemicals.

A series of basicity-tunable ionic liquids with carboxylate and sulfonate anion were designed, prepared, and applied in NO capture. Both high absorption capacity and low desorption residue were ach...

A strategy to prepare liquid anion-functionalized pillar[5]arene by incorporating a large asymmetrical cation on the rims was proposed. This kind of pillar[5]arene-based ionic liquid showed high th...

In this work, a simple dichlororesorufin-based colorimetric and fluorescent probe R-Hg with the recognition receptor of carbonothioate was designed, synthesized, and exploited to determine mercury ions in aqueous solution and living cells as well as in zebrafish. After a series of analytical tests, probe R-Hg showed some excellent characteristics, such as ultrasensitivity, high selectivity, and good water solubility. The probe solution exhibited a very large fluorescence enhancement (about 150-fold) upon addition of Hg2+. Additionally, probe R-Hg exhibited excellent sensitivity, which could quantificationally detect Hg2+ at the nanomolar level, and the detection limit was 0.49 nM. Moreover, probe R-Hg could be used as a “naked-eye” probe for monitoring Hg2+, because the color of its solution transformed remarkably from yellow into pink with the participation of Hg2+. Importantly, probe R-Hg has potential application value and has been successfully applied to the determination of Hg2+ in practical water sa...

The sensitive and accurate detection of intracellular gasotransmitter carbon monoxide (CO) is of great significance for unraveling its diverse cellular functions. Herein, we report a simple highly specific and sensitive 4-hydroxynaphthalimide-based ratiometric fluorescent probe Ratio-CO for monitoring CO levels in living cells. Probe Ratio-CO could quantitatively detect CO in the range of 0–50 μM by the ratiometric fluorescence spectroscopy method and the detection limit was measured to be about 17.9 nM. Additionally, probe Ratio-CO has been proven to possess preeminent selectivity towards CO over other bioactive species. Most importantly, the excellent response properties of probe Ratio-CO enable its applications in the monitoring of the fluctuations of CO levels in living cells by the ratiometric fluorescence imaging technique, and we thus anticipate that this probe would be a novel tool for further elucidating the biological functions of CO in living systems.

A novel anion-functionalized fluorescent ionic liquid was designed and prepared, which was capable of capturing sulphur dioxide with high capacity and could also be used as a good colorimetric and fluorescent SO2 sensor. Compared to conventional fluorescent sensors, this fluorescent ionic liquid did not undergo aggregation-caused quenching or aggregation-induced emission, and the fluorescence was quenched when exposed to SO2, and the fluorescence would quench when exposed to SO2. The experimental absorption, spectroscopic investigation, and quantum chemical calculations indicated that the quenching of the fluorescence originated from SO2 physical absorption, not chemical absorption. Furthermore, this fluorescent ionic liquid exhibited high selectivity, good quantification, and excellent reversibility for SO2 detection, and showed potential for an excellent liquid sensor.

Structural defects such as micro-pores and cracks generated during the micro-arc oxidation process can greatly reduce the corrosion resistance of the coating. This work proposed a method to improve the anti-corrosion property of the micro-arc oxidation (MAO) coating by layer-by-layer (LBL) assembling a polyurea layer on the surface of it. Organic silane (KH) and isophorone diisocyanate (IPDI) were self-assembled alternately on the MAO coating surface and formed a polyurea layer. The assembled layers were investigated using XPS, FTIR, EDS-SEM, EIS and polarization curves measurements. Three organic layers obtained couldn't be seen from SEM morphology. Whereas the XPS results showed the existence of polyurea layers with the disappearance of Al 2p signals and appearance of N 1s signals. The MAO coating surface was hydrophilic, and the contact angles of samples with odd-numbered layer (KH550 surface) were up to 95°, while the samples with even-numbered layer (IPDI surface) were about 87°, meaning that the silane and IPDI were successfully assembled on the MAO surface, improving the hydrophobicity of coating. The KH550/IPDI coating exhibited remarkably corrosion protection, and the corrosion resistance of the coating was maintained above 109 Ω·cm2 after exposure in NaCl solution for 288 h. In addition, the self-corrosion current density was under 1.46 × 10−9 mA·cm−2 after 288 h immersion, indicating that the KH550/IPDI coating would keep the anti-corrosion ability for longer time.

To decrease coefficient of friction (CoF) of the 6063 aluminum alloy modified by microarc oxidation (MAO) treatment, a MoS2 lubricating layer was synthesized on the MAO coating by hydrothermal reaction. The as-synthetized MoS2 powders demonstrated high purity and interesting micro-spheres structure assembled by many nano-lamellae. The prepared MoS2 layer was ~11 ± 3.3 μm thick, and padded the surface porosity of MAO ceramic coatings. These composite coatings were slidden against GCr15 steel counterparts in air at variable applied loads. According to the results of tribological test, the CoF of MAO/MoS2 composite coatings reduced by ~31.4%, 45.5% and 42.1% compared to single MAO coatings at 2, 4 and 6 N loads, respectively, due to the low shear strength of MoS2. The wear track of MAO/MoS2 composite coatings also displayed more uniform and smoother, causing more stable sliding process. Additionally, the existence of MoS2 layer significantly decreased the wear rate of both coatings and related counterpart balls, implying the enhanced anti-wear properties. Scanning electron microscopy (SEM) and Raman spectrometer revealed that the primary wear mechanism of single MAO coating was a combination of adhesive wear, abrasive wear and oxidation, while the MAO/MoS2 self-lubricating composite coating only showed slight abrasive wear combined with oxidation occurrence.