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Non-noble metal for surface plasmon resonance (SPR)-induced nano-enzymatic photoelectrochemical (PEC) biosensors is a promising method for broad applications. Non-noble metal bismuth (Bi) is gradually being valued for their properties such as non-toxicity, abundant reserves, and good catalysis. Meanwhile, metallic Bi nanoparticles (NPs) have superior SPR properties similar to that of noble metal. Therefore, a non-noble metal Bi/BiVO4 photoanode based on SPR was designed for the PEC detection of H2O2 in this work. The synergistic effect of BiVO4 with suitable band gap (2.5 eV) and Bi NPs with superior SPR effectively reduces the recombination of photogenerated electrons and holes, which significantly improves the PEC activity of Bi/BiVO4 electrode at low voltage. The in situ Bi/BiVO4/FTO photoelectrode not only exhibits a more comprehensive linear range of 0.005–2.6 mM with a lower detection limit of 2.0 μM but also possesses excellent selectivity for the determination of H2O2 because the coexisting substances are difficult to be oxidized at 0 V bias voltage. The investigation of Bi/BiVO4-based sensor has contributed to the development of non-noble metal for SPR-induced PEC biosensors. [ABSTRACT FROM AUTHOR]

Bismuth (Bi) is a particular element with many distinctive properties such as low toxicity or nontoxicity, high specific gravity, photoluminescence, photoelectronic and photovoltaic effects, strong oxidation ability, water insolubility, etc. These distinctive properties help to boost various applications of Bi. The recent decades have witnessed a dramatic increase in the application research of Bi‐based materials, especially on photocatalysis. This paper begins with an introduction to the history of Bi, followed by a summary of its distinctive properties, and then provides a comprehensive overview of its applications in photocatalysis, sensing, medicine, and diagnosis and treatments, with a particular focus on near‐infrared photocatalysis, flexible wearable sensor, in vivo detection and therapeutics. Finally, the main challenges and development prospects of the Bi‐based materials are introduced. With the development trends of Bi research discussed, this paper is aimed at improving the knowledge of Bi and arising the research interest of Bi in the hope of extending the applications of Bi. [ABSTRACT FROM AUTHOR]

In2S3/BiOI composites were synthesized at room temperature which significantly improved the photocatalytic degradation of tetracycline hydrochloride (TC) under visible light irradiation. Structure and morphology characterization techniques have been performed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction measurements (XRD) and X-ray photoelectron spectra (XPS). The separation ability of photogenerated carriers is enhanced due to the formation of heterojunctions of the composites. The best performance is obtained when the content of In2S3 is 7 wt%. Compared with In2S3 and BiOI alone, 7-In2S3/BiOI has the highest specific surface area and can provide more active sites. Based on the photo-electrochemical characterization and free radical tests, a photocatalytic mechanism of In2S3/BiOI composites in the presence of superoxide radicals (˙O2−) and holes (h+) is reasonably proposed. [ABSTRACT FROM AUTHOR]

BiOCl has been identified to be a promising semiconductor material with exceptional performance for photodegradation of organic pollutants. In this work, a feasible strategy to synthesize octagon‐like BiOCl nanoflakes (G‐BiOCl NFs) with novel morphology was developed by one‐step solvothermal reaction in ethylene glycol/water solution with the addition of glutamate acid. The obtained G‐BiOCl NFs with large surface areas and negatively charged surfaces possessed excellent photocatalytic activity for the degradation of organic pollutant Rhodamine B (RhB). RhB was almost completely degraded in only 4 mins under ultraviolet−visible light irradiation. It was confirmed that the holes and.O2− played crucial roles in the RhB photocatalytic degradation process. This work provided a new strategy for the preparation of efficient photocatalysts. [ABSTRACT FROM AUTHOR]

To develop a greener method to separate phenols from oils, four kinds of halogen-free zwitterions, including 1-(propyl-3-sulfonate)-triethylaminium (TEA-PS), 1-(propyl-3-sulfonate)-tripropylaminium (TPA-PS), 1-(butyl-4-sulfonate)-triethylaminium (TEA-BS) and 1-(butyl-4-sulfonate)-tripropylaminium (TPA-BS), were designed and synthesized to separate phenols from model oils via forming deep eutectic solvents (DESs) based on the formation of hydrogen bonding between OH group on phenol and the oxygen atom on SO 3 − group of the zwitterions. The effects of time, temperature, dosage of zwitterions, initial phenol content, and structure of zwitterions were investigated. The results show that the extraction process can reach equilibrium within 2 min and the extraction efficiency is not sensitive to temperature. The zwitterions separate well phenol from model oils at room temperature, and the minimum phenol contents follow the order: TEA-PS > TPA-PS > TEA-BS > TPA-BS. The minimum phenol content and the maximum extraction efficiency at 25 °C can reach 4.8 g dm −3 and 98.6%, respectively, by using TPA-BS. All the maximum extraction efficiency can be obtained with n zwitterions : n phenol of less than 0.4, which greatly reduces the dosages of extractants. Importantly, these zwitterions can avoid the introduction of halide ion, which can seriously corrode the process equipment. All these zwitterions can be easily regenerated by an anti-solvent method without an obvious mass loss and a decrease in phenol extraction efficiency. Lastly, the extraction mechanism was studied with FT-IR and the freezing points of DESs indicate that the DESs are formed through hydrogen bonding. [ABSTRACT FROM AUTHOR]

The separation of aromatics from aliphatics is challenging and energy-consuming because of the very close boiling points among these compounds and the possibility of forming azeotropes. In this work, we designed two imidazolium-based dicationic ionic liquids, [C5(MIM)2][NTf2]2 (DIL1) and [C6(MIM)2][NTf2]2 (DIL2), and found that they could highly efficiently extract aromatics from aliphatics. Three different aromatic and aliphatic mixtures, toluene/n-heptane, benzene/n-hexane and benzene/cyclohexane, were used to investigate the universality of DILs. The extractive performance of both DILs was compared with those of other promising ILs and sulfolane. The mixtures of toluene and aliphatics with different chain lengths were also investigated. The results showed that the two DILs had relatively high selectivity and distribution coefficients for different aromatic and aliphatic mixtures. At 30 °C, the highest values of selectivity and distribution coefficient for toluene/n-heptane, benzene/n-hexane and benzene/cyclohexane systems were 50.4, 64.8, and 24.9 and 1.44, 2.44, and 2.25, respectively. The performance of DILs at 30 °C was better than that at 40 °C. Besides, a higher selectivity could be obtained when toluene is used with a longer chain aliphatic, such as a selectivity of 61.4 could be obtained when the aliphatic was n-nonane. The study of the physicochemical properties of DILs showed that they were more stable than the previous ones. In a word, the two DILs were evaluated as potential solvents for the separation of aromatics from aliphatics. [ABSTRACT FROM AUTHOR]

The separation of phenolic compounds from oil mixtures is widely used in the chemical industry. In this research, we found that two types of environmentally benign quaternary ammonium-based zwitterions, betaine and l -carnitine, could be used as new extractants for the separation of phenol from model oils by forming deep eutectic solvents (DESs). The effects of extraction time, temperature, mole ratio of zwitterion to phenol and initial phenol content on the efficiency of phenol separation were investigated. The results indicated that betaine and l -carnitine could form DESs with phenol, and the DESs were insoluble in model oils. Phenol in model oils could be extracted with extraction efficiencies up to 94.6% at an l -carnitine:phenol mole ratio of 0.4 (an l -carnitine:phenol mass ratio of 0.68) and 298.2 K. Phenol in DES could be recovered using an anti-solvent, and betaine and l -carnitine could be regenerated and reused for 4 cycles without obvious decreases in extraction efficiency and extractant mass, and they were not changed in their structures after reuse. The separation mechanism was investigated using FT-IR, which showed that betaine and l -carnitine formed DESs with phenol through hydrogen bonding. [ABSTRACT FROM AUTHOR]

In this article, dicationic ionic liquids (DILs), including N , N , N , N ′, N ′, N ′-hexaethyl-ethane-1,2-diammonium dibromide (HEDBr), N , N , N , N ′, N ′, N ′-hexaethyl-propane-1,3-diammonium dibromide (HPDBr) and N , N , N , N ′, N ′, N ′-hexaethyl-butane-1,4-diammonium dibromide (HBDBr), were designed and used to extract phenolic compounds from model oil and coal tar oil. The effects of stirring time, temperature, DIL:phenol mole ratio, and initial phenol concentration on the extraction of phenol were studied. It is found that the DIL:phenol mole ratio is only around 0.3 when the highest extraction efficiency of phenol is obtained. The extraction process completes within 5 min at room temperature, and the extraction efficiency is not dependent on temperature. Also, the ultimate phenol concentration remains constant despite the difference in initial phenol concentrations. Of these DILs, HPDBr shows the lowest ultimate phenol concentration of 3.9 g/dm 3 , and the extraction efficiency of phenol can reach as high as 97.0%. These DILs can be regenerated by anti-solvent method and reused several times without significant reduction in extraction efficiency. In addition, HPDBr was demonstrated to extract phenolic compounds from real coal tar oil, and its extraction efficiency of phenolic compounds is 92.7%. The mechanism, analyzed by FT-IR, shows that there is a hydrogen bond between phenol and DIL. [ABSTRACT FROM AUTHOR]

Forming deep eutectic solvents (DESs) by quaternary ammonium salts (QASs) and phenolic compounds to extract phenolic compounds from oil mixtures is effective. However, a small amount of neutral oil is entrained in the DESs. In this work, we proposed an anti-extraction method to remove the neutral oil entrained in DESs. Low-carbon alkanes (LCAs, including n -hexane, cyclohexane, and n -nonane) were added to model DESs to remove neutral oil. We found that the LCAs could effectively remove neutral oil entrained in the DESs. Of the three LCAs, n -hexane showed the best performance, and the removal rate of neutral oil could reach as high as 92.2%. The separation process could complete within 15 min, and the removal rate of neutral oil did not change significantly with temperature. In addition, n -hexane could effectively remove neutral oils in DESs formed by real coal tar and choline chloride. The neutral oil content in the phenolic compound product decreased to only 1.9 wt%, which greatly improves the purity of the phenolic compound product. [ABSTRACT FROM AUTHOR]