Search

Using etherification to convert glycerol into biofuel additives is an effective way to solve the current problem of excess glycerol. In this study, a series of environmentally friendly (x)HPW/ZrO2 catalysts were synthesized for the etherification of glycerol and tert-butyl alcohol (TBA). The internal microstructure and acidity analysis of the synthesized samples were derived from BET, XRD, Raman spectroscopy, FTIR, SEM, NH3-TPD and Py-FTIR. The results revealed that the synthesized catalysts retained the complete Keggin structure of phosphotungstic acid (HPW) which supported on it. The (15)HPW/ZrO2 catalyst with suitable structure and acidity had an excellent catalytic effect on the etherification reaction. Driven by the (15)HPW/ZrO2 catalyst, the optimal reaction conditions were determined from parameters of reaction temperature, time, molar rate of glycerol and TBA, and catalyst dosage. 93.2% glycerol conversion and 42.5% selectivity of multi-substituted tert-butyl glycerol ethers (DTBG + TTBG) were obtained under optimal conditions. In addition, even after a total of four consecutive reactions, (15)HPW/ZrO2 catalyst still demonstrated relatively good catalytic activity.

Synthesis of 5-hydroxymethylfurfural (HMF) from carbohydrates was achieved over the homogeneous catalyst acid poly(4-styrenesulfonic acid) (PSS). The various reaction conditions like reaction temperature, reaction time, various solvent, solvent volume, and catalyst dosages were explored. The results showed that the PSS catalyst resulted in 86.8% HMF yield from fructose and 48.5% HMF yield from glucose in solvent 1-methyl-2-pyrrolidone and dimethyl sulfoxide, respectively. The catalyst has reused five cycles without obviously reduced on HMF yield, suggesting that PSS showed high catalytic activity at recycle experiment. Thus, PSS was a potential candidate for homogeneous catalyst acids and can convert carbohydrate compound into HMF conveniently.

A bithiophene donor unit, 3-alkoxy-3′-alkyl-bithiophene (TRTOR), was copolymerized with difluorobenzochalcogenadiazole (ffBZ) containing different heteroatoms on its diazole structure to afford a series of PffBZ copolymers (where Z = X, T, Se) with narrow optical bandgaps in the range of 1.34–1.47 eV. The effects of the ffBZ heteroatoms (O, S, and Se) on the optical properties, electrochemical characteristics and film morphologies of the polymers as well as the device performance were fully investigated. The results revealed that the highest occupied molecular orbitals (HOMOs) of the polymers gradually elevated accompanied by their increased materials solubility in common organic solvents as the size of the heteroatoms increased. The PffBZ copolymers exhibited a substantial hole mobility of 0.08–1.6 cm2 V−1 s−1 in organic thin-film transistors (OTFTs). The PffBX, PffBT, and PffBSe-based polymers exhibited maximum power conversion efficiencies (PCEs) of 5.47%, 10.12%, and 3.65%, respectively, in polymer solar cells (PSCs). For the PffBZ copolymers, the alkyl chain exerts a great influence on the morphology of the polymer:PC71BM blend films and hence affect the PCEs in PSCs. It was found that the performance of the polymers with branching on the 2nd position of the alkyl chain and the 3rd position of the alkoxy chain were the best among the PffBT and PffBSe-based polymers, different from the tetrathiophene-based benchmark polymer with branching on the 2nd position of the alkyl chain. X-ray diffraction revealed that all of the PffBZ-based polymers showed obvious face-on dominant orientation, and that chalcogen atoms and branched positions on the alkoxy chain have a great influence on the morphologies of the neat and blend films. The above results indicated that the branching positions and chalcogen atoms should be carefully optimized to maximize performance.

Heterojunction engineering is a very prospective approach to modulate the photocatalytic behaviors of semiconductors. Herein, Venus flytrap-like NiCo hydroxide nanoflowers (HNF) with surface modification by different contents of CoSn(OH)

Background Hepatocellular carcinoma (HCC) is a common cause of cancer-related deaths and has low sensitivity to conventional therapies. Dendritic cell (DC) loaded tumor-exosomes (TEX) have shown antitumor effects in a murine HCC model. However, the combined antitumor efftcts of DC-TEX and programmed death protein 1 antibody (PD-1 Ab) at different time application has not been investigated. Methods In this study, ectopic, orthotopic, and diethylnitrosamine (DENA)-induced HCC models were established and treated with DC-TEX alone or in combination with PD-1 Ab at different time points. Meanwhile, we established an orthotopic HCC model in BALB/C nude mice and restore t cells. Results The results showed that along with the increased number of CD8+ T cells, the PD-1+CD8+ T-cell population was also significantly increased after DC-TEX injection. The number of CD8+ T cells peaked 72 h after DC-TEX injection, and the PD-1+CD8+ T cells also showed a similar result. Subsequently, the PD-1 Ab was applied in combination with DC-TEX at a series of time points (0, 24,72, 96, 120 or 168 h). Surprisingly, the combined treatment showed strong antitumor effects and this effect was most prominent when PD-1 Ab was administerd at 72 h. In vitro, PD-1 Ab also significantly reversed the proliferative ability of PD-1+CD8+ T cells at 72 h. The combined antitumor effects of PD-1 Ab and DC-TEX were mainly through their stimulation on CD8+T cells proliferation as well as repression for T cell exhaustion. Conclusion In conclusion, the combination of DC-TEX and PD-1 Ab significantly suppresses tumor growth in a murine HCC model and that the antitumor effect is affected by the timing of PD-1 Ab treatment.

N,N-dimethylformamide (DMF) is a commonly-used solvent in industry and pharmaceutics for extracting acetylene and fabricating polyacrylonitrile fibers. It is also a starting material for a variety of intermediates such as esters, pyrimidines or chlordimeforms. However, after being used, DMF can be form 5–25% spent liquors (mass fraction) that are difficult to recycle with distillation. From the point of view of energy-efficiency and environment-friendliness, an emergent separation technology, pervaporation, is broadly applied in separation of azeotropic mixtures and organic–organic mixtures, dehydration of aqueous–organic mixtures and removal of trace volatile organic compounds from aqueous solutions. Since the advances in membrane technologies to separate N,N-dimethylformamide solutions have been rarely reviewed before, hence this review mainly discusses the research progress about various membranes in separating N,N-dimethylformamide aqueous solutions. The current state of available membranes in industry and academia, and their potential advantages, limitations and applications are also reviewed.

Driven by the exceptional success of 2,2′-bithiophene-3,3′-dicarboximide imide (BTI) for enabling high-performance polymer semiconductors, herein two BTI analogues 2,2′-bifuran-3,3′-dicarboximide (...

A planar backbone conformation is essential for enabling polymer semiconductors with high charge carrier mobility in organic thin-film transistors. Benefiting from the smaller van der Waals radius ...

3594 Background: Irinotecan and fluorouracil are the most effective drugs in the treatment of metastatic colorectal cancer (mCRC). But XELIRI (irinotecan plus capecitabine) has not been recommended in the 1st-L setting due to the toxicity in the Western countries. While, modified 3-weekly XELIRI has been proved to be effective and safe in the 2nd-L therapy in Asian mCRC patients. Therefore, this study aimed to assess the efficacy and safety of biweekly mXELIRI with reduced dose of irinotecan in the 1st-L treatment of mCRC. Methods: This was a randomized, open-label, non-inferiority study undertaken at 11 hospitals in China. Eligible patients were aged ≥18 years with unresectable metastatic histologically diagnosed colorectal adenocarcinoma; had an ECOG of 0 or 1 and at least one measurable disease according to the RECIST v 1.1 without any systemic chemotherapy for metastatic disease. Patients were randomly assigned (1:1) stratified by the location of primary tumor (left or right site) to receive 9 cycles of mXELIRI + bevacizumab (Bev) (irinotecan 150mg/m2 D1, capecitabine 1000mg/m2 bid D1-10, Bev 5mg/kg D1, Q2W) or FOLFIRI + Bev (irinotecan 180mg/m2 D1, CF 400mg/m2 D1, 5-Fu 400mg/m2 bolus D1, 5-Fu 2400mg/m2 civ 46h D1, Bev 5mg/kg D1, Q2W) followed by maintenance treatments with capecitabine + Bev or 5-FU + CF + Bev. The primary endpoint was 12-month progression-free survival (PFS) rate. The secondary endpoints included objective response rate (ORR), PFS, overall survival (OS) and safety. Results: From May, 2018 to Apr, 2021, 264 pts were randomized (mXELIRI + Bev 132; FOLFIRI + Bev 132). The median age was 61 (29-80) years old. 62.5% of the patients were men. With a median follow-up of 17.1 months, the 12-month PFS rates were 43.9% vs. 28.8% in the mXELIRI + Bev and FOLFIRI + Bev groups, respectively. The HR was 0.72 (95%CI 0.51 -1.02) which didn’t cross the predefined non-inferiority margin of 1.18 (upper bound < 1.18). The median PFS were 10.5 months vs. 9.6 months (p = 0.056, HR 0.74, 95%CI 0.55-1.01). The median OS was still not mature. The ORR were 51.5% vs. 47.0% (p = 0.460), respectively. The incidence of treatment related adverse events (TRAEs) between these two groups were similar. The most common TRAEs were neutropenia (mXELIRI + Bev vs. FOLFIRI + Bev: 51.8% vs. 57.0%), leukopenia (43.9% vs. 55.3%), anemia (54.4% vs. 45.6%), nausea (31.6% vs. 40.4%), ALT/AST increased (22.8% vs. 23.7%), diarrhea (21.1% vs. 16.7%), fatigue (20.2% vs. 23.7%), vomiting (17.5% vs. 20.2%) and hyperbilirubinemia (14.9% vs. 17.5%). No treatment- related deaths were reported. Conclusions: Biweekly mXELIRI with reduced dose of irinotecan plus bevacizumab was noninferior to the standard dose of FOLFIRI + Bev in PFS, with similar safety profile in the patients with untreated mCRC. Clinical trial number: NCT04247984. Research Sponsor: No Clinical trial information: NCT04247984.

Exosomes are protein-containing vesicles that are secreted into the blood to mediate important biological and pathological processes. The present study enrolled 86 patients with advanced hepatocellular carcinoma (HCC) and 60 healthy controls. Serum exosome levels of the patient group were significantly elevated compared with the healthy control group (P = 0.001). No significant differences were observed between patients with serum alpha-fetoglobulin levels of less than 200 ng/mL and more than 200 ng/mL. In vitro, dendritic cells (DCs) were activated by exosomes and could promote T cell proliferation, exhibiting a killing effect on HepG2 cells. In addition, DCs loaded with tumor exosomes (DC-TEX) showed an antitumor effect in a subcutaneous tumor model. This study shows exosome levels in patients with HCC to be significantly higher than in healthy individuals. Furthermore, exosomes derived from serum of patients with advanced HCC function as tumor antigens.

A new polymer acceptor poly{(N,N'-bis(2-ethylhexyl)-1,4,5,8-naphthalenedicarboximide-2,6-diyl)-alt-5,5-(3,3'-didodecyl-2,2'-bifuran)} (NDI-BFR) made from naphthalenediimide (NDI) and furan-derived head-to-head-linked 3,3'-dialkyl-2,2'-bifuran (BFR) units is reported in this study. Compared to the benchmark polymer poly(naphthalenediimide-alt-bithiophene) (N2200), NDI-BFR exhibits a larger bathochromic shift of absorption maxima (842 nm) with a much higher absorption coefficient (7.2 × 104 m-1 cm-1 ), leading to an ultranarrow optical bandgap of 1.26 eV. Such properties ensure good harvesting of solar light from visible to the near-infrared region in solar cells. Density functional theory calculation reveals that the polymer acceptor NDI-BFR possesses a higher degree of backbone planarity versus the polymer N2200. The polymer NDI-BFR exhibits a decent electron mobility of 0.45 cm2 V-1 s-1 in organic thin-film transistors (OTFTs), and NDI-BFR-based all-polymer solar cells (all-PSCs) achieve a power conversion efficiency (PCE) of 4.39% with a very small energy loss of 0.45 eV by using the environmentally friendly solvent 1,2,4-trimethylbenzene. These results demonstrate that incorporating head-to-head-linked BFR units in the polymer backbone can lead to increased planarity of the polymer backbone, reduced optical bandgap, and improved light absorbing. The study offers useful guidelines for constructing n-type polymers with narrow optical bandgaps.

Alkylphosphinates have received extensive attention in the past few decades because of their very useful mechanical properties, electrical properties, low density, and low toxicity, and have been widely used in flame-retardant materials and other fields. In this work, aluminum diethylphosphinate is successfully synthesized under atmospheric pressure. More importantly, two novel dialkylphosphinates, aluminum dioctylphosphinate and aluminum didecylphosphinate, are first synthesized and characterized. The structures of these aluminum dialkylphosphinates are confirmed by nuclear magnetic resonance, Fourier-transform infrared spectroscopy, and high-resolution mass spectrometry, and the microscopic morphology and thermal stability are analyzed by scanning electron microscopy and thermogravimetric analysis, respectively. Furthermore, conditions for the synthesis of aluminum dioctylphosphinate are optimized. Compared with the traditional method of synthesizing dialkylphosphinates under high pressure, the method reported in this paper has the advantages of high safety, easy operation, and low economic cost, which makes it suitable for industrial production.

Advanced hepatocellular carcinoma (HCC) has limited therapeutic options. Immunotherapy is a promising treatment, while sorafenib is a first-line drug-based treatment for advanced HCC. However, the efficacy of sorafenib and immunotherapy in combination, have not been clearly evaluated. Sorafenib treatment has been shown to promote immunosuppression by increasing hypoxia in orthotopic HCC models. Here, we found that sorafenib treatment in mice with orthotopic HCC increased the expression of inhibitor programmed death-ligand 1 (PD-L1) and T-regulatory cells in tumor tissues. We pulsed dendritic cells with exosomes derived from tumor cells (DC-TEX) and found that the number of T-regulatory cells decreased and the number of CD8+T cells increased. However, combining DC-TEX and sorafenib did not prolong survival in these mice. Moreover, we found that the number of PD-1+CD8+T cells significantly increased after DC-TEX treatment. Therefore, we next added PD-1 antibody (PD-1 Ab) to the treatment regimen to block the PD-1/PD-L1 pathway, and found that the exhausted CD8+T cells were restored, without affecting the number of T-regulatory cells. Thus, our data suggest that the combination of DC-TEX and PD-1 Ab enhanced the efficacy of sorafenib, but treatment with either DC-TEX or PD-1 Ab alone, did not.

Due to their high-lying lowest unoccupied molecular orbitals (LUMOs), π-conjugated polymers based on benzothiadiazole and its derivatives typically are p-type. We report here the successful development of two narrow bandgap, ambipolar donor–acceptor copolymers, PDCNBT2T and PDCNBSe2T, which are based on new cyano-substituted strong electron acceptors, 4,7-dibromo-5,6-dicyano-2,1,3-benzothiadiazole (DCNBT) and 4,7-dibromo-5,6-dicyano-2,1,3-benzoselenadiazole (DCNBSe), respectively. Compared to their polymer analogues with fluorine substituents, the LUMO was lowered by a big margin of ca. 0.6 eV and the bandgap was reduced by 0.2–0.3 eV for the cyano-substituted polymers. Therefore, the cyano-substituted benzothiadiazole polymers showed very low-lying LUMO levels of ca. 4.3 eV. Benefiting from their narrow bandgaps of 1.1–1.2 eV and appropriately positioned LUMO levels, both polymers exhibit well balanced ambipolar transport characteristics in organic thin-film transistors, which differ from the p-type dominating transport properties of their fluorinated polymer analogues. A balanced hole/electron mobility of 0.59/0.47 cm2 V−1 s−1 was achieved for polymer PDCNBT2T, and a reduced hole/electron mobility of 0.018/0.014 cm2 V−1 s−1 was observed for the benzoselenadiazole-based PDCNBSe2T due to its lower crystallinity. These results show that the electron mobility can be enhanced by approximately two orders versus the electron mobility of the previously reported 4,7-di(thiophen-2-yl)-5,6-dicyano-2,1,3-benzothiadiazole-based polymer. This improvement was achieved by using the new acceptor units without additional electron-rich thiophene flanks, which allow a higher degree of freedom in selecting the donor co-unit and more effective tuning of energy levels of frontier molecular orbitals.

The conversion of cellulose to levulinic acid (LA) and other platform chemicals is a promising route to solve the energy crisis. For this purpose, a series of new SO3H-functionalized ionic liquids (ILs), containing different halogen-anions were synthesized and applied for catalytic conversion of cellulose to LA. The structure, thermal stability, and acidity of SO3H-functionalized ILs were characterized by Nuclear magnetic resonance (NMR) spectra, Fourier-transform infrared (FT-IR), High resolution mass spectrometry (HRMS), thermogravimetric analysis (TGA), and Hammet acidity method. The results revealed that as the size of halogen anions increased, the Hammett acidity gradually increased from SO3H-functionalized ILs containing fluorine- to chlorine- and then to bromine-anions. When SO3H-functionalized ILs were used as a catalyst for the production of LA from cellulose, the yield of LA gradually increased as the size of halogen-anions increased from fluorine- to chlorine- and then to bromine-anions. Among the SO3H-functionalized ILs, 1,1-bis(3-(4-sulfobutyl)imidazolium-1-yl)butylene bromine ([BSim]Br) exhibited the best catalytic activity with 76.5% yield of LA in cellulose/[BSim]Br/H2O (m/m/m = 1:9:8) reaction system at 180 °C for 20 min, which was the highest yield compared to previous literature reports using ILs as catalyst. Besides, the [BSim]Br was easily recovered and showed high catalytic activity after five cycles. The efficient catalyst, [BSim]Br is then proposed to have a great potential for mass production of LA from biomass.

A series of new SO3H-functionalized ionic liquids (ILs) were synthesized and characterized, which were successfully applied to catalyze cellulose to produce levulinic acid (LA) via one-pot reaction. The structure, thermal property, and acidity of ILs were characterized by NMR, TGA, and Hammett acidity measurement. The Hammett acidity (H0) of ILs increase in the following order: [BSim]H2PO4

The purpose of the present study was to identify an "easy-to-adopt" strategy to enhance immune responses using functionalized alginate (ALG) nanoparticles (MAN-ALG/ALG=OVA NPs), which were prepared by CaCl2 cross-linking of two different types of ALG. The mannose (MAN) modified ALG (MAN-ALG) was used for dendritic cell targeting. The other component, composed of ovalbumin (OVA), a model antigen, is conjugated to ALG (ALG=OVA) via pH sensitive Schiff base bond. Grafting of alginate was demonstrated by FT-IR and 1H NMR, while the morphological structure, particle size, Zeta potential of MAN-ALG/ALG=OVA NPs were measured using TEM and DLS. The OVA releasing behavior of MAN-ALG/ALG=OVA NPs was determined as a function of pH. Antigen uptake was examined by flow cytometry and confocal laser scanning microscopy in vitro using mouse bone marrow dendritic cells (BMDCs). The results showed that MAN-ALG/ALG=OVA NPs facilitated antigen uptake of BMDCs and cytosolic release of the antigen. Significant up-regulation of cytokine secretion and expression levels of the surface co-stimulatory molecules were also observed in MAN-ALG/ALG=OVA NPs-treated BMDCs, compared to free OVA. In vivo bio-distribution study using Cy7 (a near-infrared fluorescence dye) labeled MAN-ALG/ALG=OVA NPs showed efficient in vivo trafficking of the nanoparticles from the injection site to the draining lymph nodes. Moreover, MAN-ALG/ALG=OVA NPs were found to enhance cross-presentation of OVA to B3Z T cell hybridoma in vitro. Subcutaneous administration of MAN-ALG/ALG=OVA NPs also induced major cytotoxic T lymphocytes (CTL) response and inhibition of E.G7 tumor growth in C57BL/6 mice. In summary, we report here that the MAN-ALG/ALG=OVA NPs have the potential as a potent nanovaccine for cancer immunotherapy.

Building blocks having a high degree of backbone planarity, good solubilizing characteristics, and well-tailored physicochemical properties are highly desirable for constructing high-performance polymer semiconductors. Due to the detrimental steric hindrance created by alkyl chain substituents at the 3- and 3′-positions of bithiophene, “head-to-head” linkage containing 3,3′-dialkyl-2,2′-bithiophenes (BTR) are typically avoided in materials design. Replacing alkyl chains with less steric demanding alkynyl chains should greatly reduce steric hindrance by eliminating two H atoms at the sp-hybridized carbon center. Here we report the synthesis of a novel electron donor unit, 3,3′-dialkynyl-2,2′-bithiophene (BTRy), and its incorporation into conjugated polymer backbones. The alkynyl-functionalized head-to-head bithiophene linkage yields polymers with good solubility without sacrificing backbone planarity; the BTRy-based polymers show a high degree of conjugation with a narrow bandgap of ∼1.6 eV. When incorpora...

In this study, the photochemical internalization (PCI) technique was adopted in a nanoparticle-based antigen delivery system to enhance antigen-specific CD8+ T cell immune response for cancer immunotherapy. Pheophorbide A, a hydrophobic photosensitizer, grafted with polyethylenimine (PheoA-PEI) with endosome escape activity and near-infrared imaging capability was prepared. A model antigen ovalbumin (OVA) was then complexed with PheoA-PEI to form PheoA-PEI/OVA nanoparticles (PheoA-PEI/OVA NPs) that are responsive to light. Flow cytometry analysis revealed increased endocytosis in a murine dendritic cell line (DC2.4) that was treated with PheoA-PEI/OVA NPs compared to free OVA. Generation of reactive oxygen species (ROS) in DC2.4 cells was also confirmed quantitatively and qualitatively using 2′,7′-dichlorodihydrofluorescein diacetate (DCFH-DA). Confocal laser scanning microscopy (CLSM) further demonstrated that the PheoA-PEI/OVA NPs enhanced cytosolic antigen release after light stimulation. Moreover, Phe...

Currently, n-type acceptors in high-performance all-polymer solar cells (all-PSCs) are dominated by imide-functionalized polymers, which typically show medium bandgap. Herein, a novel narrow-bandgap polymer, poly(5,6-dicyano-2,1,3-benzothiadiazole-alt-indacenodithiophene) (DCNBT-IDT), based on dicyanobenzothiadiazole without an imide group is reported. The strong electron-withdrawing cyano functionality enables DCNBT-IDT with n-type character and, more importantly, alleviates the steric hindrance associated with typical imide groups. Compared to the benchmark poly(naphthalene diimide-alt-bithiophene) (N2200), DCNBT-IDT shows a narrower bandgap (1.43 eV) with a much higher absorption coefficient (6.15 × 104 cm-1 ). Such properties are elusive for polymer acceptors to date, eradicating the drawbacks inherited in N2200 and other high-performance polymer acceptors. When blended with a wide-bandgap polymer donor, the DCNBT-IDT-based all-PSCs achieve a remarkable power conversion efficiency of 8.32% with a small energy loss of 0.53 eV and a photoresponse of up to 870 nm. Such efficiency greatly outperforms those of N2200 (6.13%) and the naphthalene diimide (NDI)-based analog NDI-IDT (2.19%). This work breaks the long-standing bottlenecks limiting materials innovation of n-type polymers, which paves a new avenue for developing polymer acceptors with improved optoelectronic properties and heralds a brighter future of all-PSCs.

Polythiophenes, built on the electron-rich thiophene unit, typically possess high-lying energy levels of the lowest unoccupied molecular orbitals (LUMOs) and show hole-transporting properties. In this study, we develop a series of n-type polythiophenes, P1-P3, based on head-to-head-linked 3,3'-dialkoxy-4,4'-dicyano-2,2'-bithiophene (BTCNOR) with distinct side chains. The BTCNOR unit shows not only highly planar backbone conformation enabled by the intramolecular noncovalent sulfur-oxygen interaction but also significantly suppressed LUMO level attributed to the cyano-substitution. Hence, all BTCNOR-based polymer semiconductors exhibit low-lying LUMO levels, which are ∼1.0 eV lower than that of regioregular poly(3-hexylthiophene) (rr-P3HT), a benchmark p-type polymer semiconductor. Consequently, all of the three polymers can enable unipolar n-type transport characteristics in organic thin-film transistors (OTFTs) with low off-currents ( I

Imidazolium ionic liquids functionalized UiO-66-NH2 MOFs were synthesized by two different approach, further applied as efficient catalysts for the catalytic conversion of CO2 into cyclic carbonates. The functionalized UiO-66-NH2 were investigated using various characterization technologies including XRD, NMR, FT-IR, XPS, TG-DTG, TEM, N2-adsorption, and NH3-TPD. The octahedron structure of UiO-66-NH2 becomes rough after UiO-66-NH2 interacted with 1-(4-carboxybutyl)-3-methylimidazolium bromide via amidation, while some small grains were formed around UiO-66-NH2 species when UiO-66-NH2 was functionalized by 1-(3-sulfopropyl)-3-methylimidazolium bromide ([SPMIM]Br) via the H2N– and HSO3– interaction. Moreover, when [SPMIM]Br was grafted onto the surface of UiO-66-NH2, a higher catalytic activity was found to exhibit 98.12% conversion of epichlorohydrin (ECH) and 98.23% selectivity to chloropropene carbonate (CPC) under optimized conditions (Initial pressure 2.5 MPa, 1.2 wt% catalyst of ECH, 95 °C, reaction time 8 h). No significant deactivation of the catalyst was observed after the [SPMIM]Br functionalized UiO-66-NH2 was reused three times. Furthermore, several additional coupling reactions were investigated with other epoxides as substrates.

Biselenophene (BS) is generally considered as a promising building block for constructing organic semiconductors, and the 3-positions of selenophene in BS offer a great opportunity for further structural modification. Herein, a novel fluorinated biselenophene, 3,3′-difluoro-2,2′-biselenophene (BSF), was designed and synthesized successfully, and subsequently incorporated into a polymer backbone leading to the resulting polymer PNDIBSF. The polymer backbone planarity was significantly improved via the enhanced intramolecular noncovalent Se⋯F coulombic interactions. Meanwhile, the electronic structure of the polymer was effectively tuned by the high electronegativity of F atoms. All-polymer solar cells (all-PSCs) with J71 and PNDIBSF as polymer donor and acceptor achieved power conversion efficiency (PCE) of 5.20%. In comparsion, all-PSCs based on the nonfluorinated analogue polymer acceptor (PNDIBS) had low PCE of 2.74%. The results demonstrated that BSF is a promising building block for constructing polymer acceptor in all-PSCs, and the fluorination offers a sufficient strategy for further improving performance of selenophene-based polymer semiconductors.

Narrow bandgap (1.37-1.46 eV) polymers incorporating a head-to-head linkage containing 3-alkoxy-3'-alkyl-2,2'-bithiophene are synthesized. The head-to-head linkage enables polymers with sufficient solubility and the noncovalent sulfur-oxygen interaction affords polymers with high degree of backbone planarity and film ordering. When integrated into polymer solar cells, the polymers show a promising power conversion efficiency approaching 10%.