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Arsenite (AsO2–) is a toxic pollutant for the environment and very harmful to human health. Hence, highly selective and ultrasensitive detection of AsO2– is a very significant issue for a scientifi...

By rationally introducing multi-interactions sites, supramolecular polymer networks (SPN-TDPG) has been successfully designed and constructed. SPN-TDPG gel shows aggregation-induced emission, meanw...

It is noteworthy that highly selective molecular recognition endows host-guest gels, especially hydrogel, with valuable properties. Therefore, in pure water, a supramolecular hydrogel (SH-α-CD) was constructed by using benzimidazolium-based positive charged guest molecule (J2) assembled with cyclodextrin (α-CD) through host-guest interaction, and accompanied an aggregation-induced emission (AIE). The self-assemble process of the hydrogel-based AIEgen was investigated using 1H NMR titration, 2D NOESY, XRD and SEM. In particular, the hydrogel-based AIEgen was investigated as a good candidate for fluorescent quenching and gel state destruction dual-channel recognizing negative charged dye molecule methyl orange (MO). The competitive inclusion interaction triggered the dissolution of aggregate, which induced the gel to transform into sol, with disappearance of the AIE of SH-α-CD. However, the addition of the competitive dye molecules methylene blue (MB) and xylenol orange (XO) only made the fluorescence quenching of hydrogel-based AIEgen. Meanwhile, the hydrogel-based AIEgen also exhibited an excellent thermal responsiveness under temperature transition. Such a performance is highly beneficial for potential applications in probe material for organic dye molecules.

Recently, ultrasensitive detection and multi-guest sensing have received extensive attention due to their high sensitivity and efficiency. Herein, we report a novel approach to achieve ultrasensitive detection of multi-analyte. This approach is concluded as "rationally introduce Aggregation-Induced Emission (AIE) into chemosensor". According to this approach, by rationally introducing self-assembly moiety, the obtained chemosensor DNS could serve as a novel AIEgen and show strong AIE in DMSO/H2O (water fraction 80%) binary solution. Interestingly, a simple fluorescent sensor array based on the DNS has been developed. This sensor array could selectively sense Fe3+, Al3+, H2PO4- and L-Arg in water solution. More importantly, this sensor array shows ultrasensitive detection for Fe3+, Al3+ and L-Arg. The LODs of the sensor array for Fe3+, Al3+ and L-Arg are in the range of 3.54×10-9M to 9.42×10-9M. Moreover, H2PO4- could realize the reversible detection of Fe3+ in the DMSO/H2O (water fraction 80%) solution. Meanwhile, DNS-based test papers and thin films were prepared, which could serve as test kits for convenient detection Fe3+, Al3+, and L-Arg in water. In addition, they could also act as efficient erasable fluorescent display materials.

A bi-component supramolecular gel (RQ) was successfully constructed by the assembly of the gelators 4-aminophenyl functionalized naphthalimide derivative (R) and tri-(pyridine-4-yl)-functionalized trimesic amide (Q) in DMSO–H2O (6.1 : 3.9, v/v) binary solution. The gel RQ exhibits excellent self-healing capacity. Interestingly, the RQ could fluorescently detect and reversibly remove Hg2+ from water through cation–π interactions with high selectivity, efficient adsorption and quick response. The limit of lowest detection (LOD) of the RQ for Hg2+ is 4.52 × 10−8 M and the separation ratio is 91.14%. Moreover, the RQ could be efficiently recycled and regenerated with little loss via a simple treatment by I−. Notably, thin films based on RQ and RQ + Hg2+ were prepared, which could serve as convenient and efficient test tools for the detection of Hg2+ and I−, respectively. This work provided an efficient method and novel supramolecular gel material for the separation and detection of Hg2+.

A novel supramolecular aggregation induced emission (AIE) π-gel (ONT) was constructed by using a functionalized trimesic amide (TCP) molecule assembled with a bis-pyridine functionalized naphthalene diimide (ND) molecule using a non-covalent interaction. The ONT showed strong AIE at 468 nm. Furthermore, the ONT could detect and adsorb ferric (Fe3+) or cupric (Cu2+) ions from water. Meanwhile, a thin film based on supramolecular AIE π-gel ONT was prepared, which could be used as a fluorescent security display material for detecting Fe3+ or Cu2+. Thus, the AIE π-gel ONT shows potential for practical applications in efficient multi-analyte detection and separation and as a fluorescent display material.

Herein, a novel way to design and construct multi-functional spongy supramolecular polymer gels through an easy to make tripodal guest (TA) and a naphthalimide functionalized-pillar[5]arene host (AP5) has been developed. According to this approach, a novel pillar[5]arene-based supramolecular polymer gel (SHG) was constructed via multi-non-covalent interactions such as host-guest inclusion, C-Hπ, ππ and hydrogen bonds and so on. Interestingly, the SHG exhibits a spongy structure and strong aggregation induced emission (AIE). Furthermore, the SHG also exhibited multi-responsiveness toward outer stimuli such as heating-cooling, pH, competitive agents and mechanical. More importantly, the SHG xerogel shows separation properties for Fe3+, methyl orange, methylene blue and sudan I dyes. The separation rates of SHG xerogel for Fe3+ ions and organic dyes can reach up to 99.8%. Simultaneously, the SHG could ultrasensitively detect Fe3+ (LOD is 0.9 nM). In addition, a thin film based on SHG was also prepared, which was confirmed to be a convenient test kit for detecting Fe3+.

Efficient detection of explosives (e.g. picric acid) and toxic compounds (e.g. cyanide) is an important task. Herein, we report a simple and efficient method for the selective and sensitive detection of picric acid (PA) and CN−via a novel guest competitive controlled aggregation-induced emission (AIE) method. First, a tripodal host compound (TG) based on a tris-naphthalimide derivative was designed and synthesized. The TG can self-assemble to a supramolecular system and show blue AIE. Then, we employed the TG-based supramolecular system as a novel supramolecular sensor (S-TG). Interestingly, S-TG could selectively detect PA through a competitive binding interaction, and the detection limit (LOD) of S-TG for PA is 1.19 × 10−8 M. In this process, the self-assembly of S-TG was destroyed and a TG and PA complex (TG–PA) was produced, meanwhile, the AIE of S-TG was quenched. More interestingly, TG–PA could act as a novel supramolecular sensor for the AIE fluorescent ‘turn-on’ detection of CN−, and the LOD of TG–PA for CN− is 7.45 × 10−7 M. Moreover, PA and CN− test kits were prepared by loading S-TG or TG–PA on silica gel plates. These test kits could conveniently and efficiently detect PA or CN− with high selectivity and sensitivity.

A novel bis-component AIE-gel TG was facilely constructed from two "easy-to-synthesize" tripodal gelators by a simple host-guest self-assembly process. Interestingly, the TG shows strong aggregation-induced emission (AIE) and could be used for highly efficient and sensitive detection and separation of ions (CN-, Fe3+ and H2PO4-). The LODs (limits of lowest detection) of TG for CN-, Fe3+ and H2PO4- are in the range of 4.93 × 10-9-7.80 × 10-8 M. Meanwhile, the xerogel of TG could adsorb and separate Fe3+ from aqueous solutions, and the adsorption rate is 96%. In addition, a thin film based on the TG could act as a convenient test kit for the detection of CN- and Fe3+. What is more, the TG-Fe film could not only be used as an erasable secure fluorescent display material, but also as a convenient reversible H2PO4- test kit.

Herein, we report two novel approaches for highly sensitive detection and efficient adsorption of formaldehyde and 3-fluorobenzaldehyde by forming a water-soluble supramolecular polymer and an aggregation-induced emission enhancement (AIEE) hydrogel, respectively. The host compound DTA could highly selectively and sensitively detect formaldehyde by forming a water-soluble supramolecular polymer in pure water. The LOD of DTA for formaldehyde was 1.79 × 10−8 M. More importantly, DTA could also efficiently adsorb formaldehyde from its water solution, and the adsorption percentage was 98.41%. In addition, DTA could also selectively detect 3-fluorobenzaldehyde from its isomers by forming a supramolecular AIEE hydrogel. The LOD of DTA for 3-fluorobenzaldehyde was 8.87 × 10−9 M; this result reached an ultrasensitive level. These methods are novel and useful approaches for highly sensitive detection and adsorption of aldehydes, as well as new ways for the construction of water-soluble supramolecular polymer materials and hydrogels.

Abnormal formaldehyde (FA) is known to induce a variety of diseases. Herein, we report a novel and efficient method for ultrasensitive detection of formaldehyde in gas and solutions by a catalyst preplaced sensor based on the pillar[5]arene derivative (DP5J). By the catalyzation of (CF3SO3)2Bi, DP5J could selectively and sensitively sense formaldehyde through an aggregation-induced emission (AIE) “turn-on” response within 7.5 s, and the detection limits for formaldehyde is 3.27 × 10–9 M. Moreover, a FA test kit was prepared by loading the catalyst (CF3SO3)2Bi preplaced DP5J sensor (DP5J-Bi) on a silica gel plate. The test kit could conveniently and efficiently detect formaldehyde in gas or solution with ultrasensitivity. The catalysts preplaced method and FA reaction-induced AIE fluorescence “turn-on” mechanism is a novel approach to achieve ultrasensitive detection of FA. Importantly, it is also a novel approach for the efficient detection of other volatile organic compounds.

The novel recovery process of potassium oxide and alumina from alunite concentrate was studied under different conditions, and the key technology of this process was the combination of high-temperature reductive calcination and low-temperature Bayer process. Results showed that high-temperature reductive desulfurization achieved efficient removal of sulfur in potassium aluminum sulfate, and it also accomplished the selective leaching of aluminum and potassium on the premise that the alkaline-digesting properties of alumina was kept. The desulfurization degree reached 75%, and almost all of aluminum potassium sulfate was decomposed in desulfurization process. The leaching rate of potassium oxide was 86% in hydro-leaching procedure. The digestion rate of alumina in hydro-leaching residues reached 80% as a Na2Ok of 140 g/L, a temperature of 150 °C, and a solid-liquid ratio of 1: 6 after 60 min in low-temperature Bayer process.

An easy-to-make supramolecular polymer was successfully constructed by self-assembly of tripodal tri-(pyridine-4-yl)-functionalized trimesic amide (DTB) in DMSO–H2O binary solutions. The supramolecular polymer DTB showed strong white aggregation-induced emission (AIE) in the solid state as well as in water suspensions. DTB could also form a stable supramolecular polymer hydrogel (DTB-G) in pure water. Interestingly, DTB showed excellent coordination ability for rare earth metal ions (Tb3+, Eu3+, La3+, Th4+ and Ce3+) and formed the corresponding complexes (DTB-Ms). Interestingly, by introducing the above-mentioned rare earth metal ions, the fluorescence colour of the obtained DTB-Ms showed corresponding variations. By inseting UV-LED lamps (λ = 365 nm) into different rare earth metal ion-coordinated xerogel DTB-Ms in small test tubes, a series of LED devices with multicolour lights were obtained. Therefore, DTB and DTB-Ms can act as fluorescence colour-tunable photoluminescence materials.

A novel organic gelator (WJ) based on benzimidazole and acylhydrazone naphthol moities has been designed and synthesized. The organic gelator (WJ) could form a stable organogel (WJG) with strong aggregation-induced emission (AIE). Interestingly, the WJG shows multi-stimuli-response for many analytes such as CN−, Al3+ and Fe3+ and L-Cys. Therefore, a multi-analyte sensor array based on WJG has been successfully developed. The WJG presents selective fluorescent and colorimetric response for CN−. Meanwhile, the WJG could selectively identify Fe3+ and Al3+ in the gel state. With the addition of Fe3+ the yellow-green AIE of WJG was quenched. In addition, the AIE of WJG could be selectively recovered by adding L-Cys. So the AIE presents an “on–off–on” type by alternatively adding Fe3+ and L-Cys. Moreover, upon the addition of Al3+, the yellow-green AIE of WJG shows a blue shift and changes to blue. The detection limits of the sensor array for CN−, Al3+ and Fe3+ are 3.02 × 10−6 M, 5.78 × 10−8 M, and 3.81 × 10−9 M, respectively. The WJG could act as a multi-analyte detection and fluorescent display material.

The selective detection and separation of target ions or molecules is an intriguing issue. Herein, a novel supramolecular organic framework (SOF-THBP) was constructed by bis-thioacetylhydrazine functionalized pillar[5]arenes. The SOF-THBP shows a fluorescent response for Fe3+ , Cr3+ , Hg2+ and Cu2+ ions. The xerogel of SOF-THBP shows excellent recyclable separation properties for these metal ions and the absorption rates were up to 99.29 %. More interestingly, by rationally introducing these metal ions into the SOF-THBP, a series of metal-ion-coordinated SOFs (MSOFs) such as MSOF-Fe, MSOF-Hg and MSOF-Cu were constructed. These metal ions coordinated MSOFs could selectively sense F- , Br- , and l-Cys, respectively. The detection limits of these MSOFs for F- , Br- and l-Cys were about 10-8 m.