Search

A perylene bisimide based electrolyte PDIN-TEMPO pendent with a stable radical 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) was synergistically integrated and used as a thickness-insensitive cathode interlayer for efficient organic solar cells.

Perovskite and organic solar cells usually require electron-transport interlayers to efficiently transport electrons from the photoactive layer to the metal electrode. In general, pure organic or i...

The development of a facile approach to simultaneously detect and separate Hg(ii) ions in an aqueous solution is a challenging topic in the chemosensing field. Herein, we focus on constructing the Hg(ii)-sensitive fluorescence “turn-on”-type composite materials by using halloysite nanotube (HNT) as substrate. Two types of HNTs-based chemosensors, HNTs-PHT and HNTs-BP, were developed in this study, which exhibit Hg(ii)-sensitive fluorescence “turn on” behavior by forming interparticle and intraparticle excimers, respectively. Fortunately, HNTs-PHT is able to effectively restrict the solvent relaxation of π–π* transition and make it a better detection tool in aqueous solution than HNTs-BP. The addition of Hg(ii) can trigger a dramatical increase at 469 nm in emission curves of HNTs-PHT, which cannot exhibit emission behaviors without the addition of Hg(ii). Furthermore, the formation of interparticle excimers makes Hg(ii) serve as a crosslinker to aggregate HNTs-PHT into precipitations. Following this way, Hg(ii) ions can be facilely removed from the water via a simple filtration or centrifugation approach. The as-prepared HNTs-PHT shows high specificity and precision in simultaneously detecting and separating Hg(ii) without the recourse to energy consumption, which will give a novel insight to deal with heavy metal pollution.

Non-fused near-infrared electron acceptors based on a naphthobistriazole core were developed for organic solar cells with efficiencies over 10%.

Single-component organic solar cells (SCOSCs) with high stability and simplified fabrication process are supposed to accelerate the commercialization of organic photovoltaics. However, the types of photo-active materials and photovoltaic performance of SCOSCs are still far lagging behind the bulk-heterojunction type organic solar cells (BHJ OSCs). It is still an arduous task to introduce new photo-active materials into SCOSCs, aiming to improve the efficiencies of SCOSCs. One feasible way is to construct double-cable polymers with new structures and tune conformation, morphology and mobility for the improvement in power conversion efficiencies (PCEs). Hence, in this work, we constructed a new double-cable polymer PBTT-BPTI by introducing fused core 5,7-dibromo-2,3-bis(2-ethylhexyl)benzo[此处b,c斜体么? 正文中斜了]dithiophene-4,8-dione (TTDO) into the main backbone and benzo[ghi]-perylene triimide (BPTI) unit into the side chain. Both of the two units show strong electron-withdrawing property, which are expected to broaden absorption spectra and enhance intermolecular interaction. The double-cable polymer exhibited a broad absorption in the range of 300-700 nm with an optical band gap (Eg) of 1.79 eV. The PCE of PBTT-BPTI-based SCOSCs was 2.15%, which may be limited by the unconstructed efficient electron transporting channels.

It is possible to stabilize the O–W, O–Sn, R–OOSn and ST3 terminations of the α-SnWO4(010) surface. The O–Sn termination exhibits a low overpotential value of 0.51 V, showing remarkable oxygen evolution reaction (OER) performance.

Maleimide-functionalized HNTs (HNTs-I) were prepared and explored as a nanophotoinitiator. Vinyl monomers can be grafted onto the nanotubes following a spatially controllable, metal-free and non-contact photoinitiated approach. The obtained HNTs-I were further used in a 3D printing system to fabricate hydrogels with designed configurations.

Double-cable conjugated polymers have been successfully applied into single-component organic solar cells (SCOSCs) in recent years. The chemical structures of conjugated backbones and aromatic cable units, and the rational tuning of nanophase separation between them, are clue factors for double-cable polymers to further enhance the photovoltaic performance. In this work, we introduced a benzothiadiazole (BT) unit into the backbone of double-cable polymers, where BT was conjugated with two linkers, thiophene and thienothiophene, which were used to control the aggregation behavior. The studies reveal that, although thiophene-containing polymer backbones show less aggregation tendency, the corresponding perylene bisimide (PBI) side units form better stacking. Therefore, thiophene-based double-cable polymers had high hole/electron mobilities and hence a high efficiency of 4.35%, while thienothiophene-containing polymer exhibited a low efficiency of 2.35%. These results demonstrate that BT-polymers display a promising application for high performance double-cable conjugated polymers for SCOSCs.

Two metal–organic coordination complexes whose chemical formulae were [Co2(Htpt)2(H2O)2]·CH3CN}n (1) and [Co(H2tpt)2]·3H2O (2) based on the polydentate 4-(2,4,6-tricarboxyphenyl)-2,2′,6,2″-terpyridine ligand (H3tpt) have been synthesized using a hydrothermal reaction method, and their structures were determined via a series of characterization methods. The as-prepared coordination complexes were studied via single-crystal X-ray diffraction, powder X-ray diffraction, elemental analysis, and thermogravimetric analysis. Structural analysis revealed that complex 1 has a 2D-layered structure with a (3,3)-linked hcb network, while complex 2 features discrete structure, which is further extended into a 3D supramolecular network via H-bond interactions. Their treatment activity on osteoarthritis induced by anterior ligament reconstruction was evaluated. First, the inflammatory response in the bone joint was assessed using an enzyme-linked immunosorbent assay detection kit. The activation of the nf-κb signaling routine at the bone joint was assessed using real-time reverse transcription polymerase chain reaction.

For new ladder-type oligomers and polymers with versatile and robust synthetic strategies, in this study, four fully conjugated ladder-type overcrowded 9,9'-bifluorenylidene-based compounds and oligomers (

An organic-inorganic hybrid electrolyte based on a cyclic Ti-oxo cluster as the inorganic core and naphthalene-based organic ammonium bromide salts as the electrolyte was developed with easy synthesis and low cost. The new hybrid electrolyte exhibits excellent solubility in methanol, aligned work function, good conductivity, and amorphous state in thin film, enabling its successful application as a cathode interlayer in organic solar cells with a high power conversion efficiency of 17.19 %. This work demonstrates that the hybrid electrolytes are a new kind of semiconductor, exhibiting promising applications in organic electronics.

Symmetric ladder-type oligo(p-aniline)s and poly(p-aniline)s were successfully synthesized by an intramolecular ring closure in a highly efficient SNAr reaction from oligo(p-phenylene)s and poly(p-phenylene)s with fluorine (F) and secondary amine (NH) groups. Unlike Cadogan ring closure, the newly designed cyclization reaction will not produce a mixture of symmetric and nonsymmetric structures. Moreover, the introduction of the F atom does not hinder Suzuki polymerization. The result indicates that preparing regular oligomers and polymers with a nitrogen bridge is possible.

A facile strategy for the free radical polymerization and coupling of −OH groups and −NCO groups in one pot was carried out to synthesize hyperbranched poly(6-O-methacryloyl mannose/2-isocyanatoeth...

Data encryption, protection, and anticounterfeiting are crucial in the modern information society. Though a number of technologies have been developed, data security is still facing severe challeng...

Benzothiadiazole (BT) is an electron-deficient unit with fused aromatic core, which can be used to construct conjugated polymers for application in organic solar cells (OSCs). In the past twenty years, huge numbers of conjugated polymers based on BT unit have been developed, focusing on the backbone engineering (such as by using different copolymerized building blocks), side chain engineering (such as by using linear or branch side units), using heteroatoms (such as F, O and S atoms, and CN group), etc. These modifications enable BT-polymers to exhibit distinct absorption spectra (with onset varied from 600 nm to 1000 nm), different frontier energy levels and crystallinities. As a consequence, BT-polymers have gained much attention in recent years, and can be simultaneously used as electron donor and electron acceptor in OSCs, providing the power conversion efficiencies (PCEs) over 18% and 14% in non-fullerene and all-polymer OSCs. In this article, we provide an overview of BT-polymers for OSCs, from donor to acceptor, via selecting some typical BT-polymers in different periods. We hope that the summary in this article can invoke the interest to study the BT-polymers toward high performance OSCs, especially with thick active layers that can be potentially used in large-area devices.

In order to adapt to new situation of cascade hydropower enterprises (CHEs) participating in the joint market of day-ahead energy and frequency regulation (FR), a short-term optimal scheduling strategy for cascade hydropower plants (CPPs) is proposed. Firstly, the development situation of AGC in China is introduced and the CPPs’ AGC mode of participation in FR from the perspective of economy and solvability is analyzed. Secondly, for maximizing the revenue, the economic dispatching model of CPPs based on the two-part FR compensation mechanism is proposed, which combines the benefits of both the energy and FR. Finally, a two-stage optimization method that couples the load distribution among multi plants with the economic operation of a single plant is proposed for solving the model above. The experimental results show that the two-stage optimization method has good convergence and robustness in solving the proposed model, and compared with the single energy model, the total benefits of the proposed model increases by $ \$ $ 72935.6 (5.54%) through optimizing the distribution of electricity quantity and AGC capacity, which provides a new idea for cascade hydropower enterprises (CHEs) to explore market dividend and optimize market decision-making.

We present the results of the generalized-gradient approximation of Perdew, Burke and Ernzerhof (GGA-PBE) and the Heyd–Scuseria–Ernzerhof (HSE06) hybrid functional calculations of the atomic and the electronic structures of ZnWO4 (010) surfaces. The total energies obtained from these calculations are used to analyze the thermodynamic stability of the surfaces. The surface phase diagrams are constructed by surface Gibbs free energies obtained as a function of temperature and oxygen partial pressure. Our results suggested that the stable area of the surface terminations of ZnWO4 (010) has little correlation with the functional selected. The stability phase diagram shows that O-Zn, DL-W, and DL-Zn terminations of ZnWO4 (010) can be stabilized under certain thermodynamic equilibrium conditions. Based on the HSE06 hybrid functional, we calculate the electronic structures for three possible stability surface terminations. It is found that there is a fat band of the surface states in DL-W termination, which shows a delocalized feature. This fat band acts as an electron transition bridge between the valence band (VB) and conduction band (CB). It contributes to visible-light absorption by two-step optical transition with the first transition from the VB to the fat band and the second from the fat band to the CB. Significantly, the conduction band minimum (CBM) band edge position of DL-W termination is favourable for H2 evolution as the CBM edge is located above the water reduction level (H+/H2). Simultaneously, DL-W termination's valence band maximum (VBM) potential shows a strong potential for O2 generation from water oxidation because of the higher VBM edge with respect to the water oxidation level (H2O/O2). These results may help explore ZnWO4 (010) surfaces' intrinsic properties, providing a helpful strategy for experimental studies of ZnWO4-based photocatalysts in the future.

Side-chain engineering plays a significant role in the design of conjugated materials. In this work, a series of conjugated polymers PBDB-T-R with functionalized groups at the end of side units were developed as electron donor for organic solar cells (OSCs). The donor polymers PBDB-T-I and PBDB-T-OAc with iodine and acetate end groups exhibited similar absorption and energy levels, but showed much improved PCEs in OSCs compared to the polymer PBDB-T-H without substitutions at the end groups. Additionally, we found that PBDB-T-I and PBDB-T-OAc based cells exhibited optimized performance when using chloroform as solution-processed solvent without any additives. These results indicate that these conjugated polymers can act as self-additive to fabricate photoactive layers via solution process in OSCs.

We demonstrate the use of a supernormal valence transition-metal (Ce(IV) and Cu(III))-mediated redox system for the surface grafting on the halloysite nanotubes (HNTs). Following this way, commonly-used vinyl monomers were grafted on HNTs in one step under mild condition. The grafting was evidenced using FTIR, X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The micro-morphology was carefully characterized by transmission electron microscope (TEM). The results indicate that the surface grafting reaction was successfully processed in all cases, in which the Ce(IV) shows a much higher initiation activity than that of Cu(III). Then a uniform hydrogel was constructed by mixing poly(triethyl(4-vinylbenzyl)phosphonium chloride-grafted HNTs (HNTs-P(Et-P)) with sodium polyacrylate-grafted HNTs (HNTs-P(AA-Na)), which show desirable antibacterial activity.

Development of oral phosphorus binding agent with desirable biocompatibility and stability is full of significance in the treatment of chronic kidney disease. In this study, a natural product, cellulose, was selected as the substrate agent in which the –OH groups are able to chelate with Ce(IV) to generate the radicals and thereby initiate the surface grafting polymerization. Following this way, allylamine-grafted cellulose was prepared (ALE-CLS) under mild environment with high grafting ratio (160.2%) and desirable phosphorus binding capacities (23.3 mg/g). The phosphorus binding capacity increases with the rise of grafting ratio. The degradation tests give the result that the product possesses a good stability in acid environment and oxidation environment, suggesting a good stability in gastrointestinal tract. The in vivo experiment is also conducted to reveal the effect on reducing the serum phosphate levels in healthy rats and rats with hyperphosphatemia. The prepared ALE-CLS shows a much lower swelling ratio than that of RenaGel® (0.25 vs 3.69), which may serve as a good candidate as oral phosphorus binding agent with less gastrointestinal discomfort.

Background Over the past decade, endoscopic approaches have been increasingly successful in removing various types of extra-dural lesions from the skull base. Resection of tuberculum sellae meningiomas (TSMs) is challenging. The endoscopic endonasal approach (EEA) for the removal of TSMs is currently an acceptable surgical approach in neurosurgery and, despite the surgical results, the indications and limitations of this approach remain controversial. Objective This paper reviews the authors' experience and outcomes with the EEA for TSM, as well as postoperative complications. Methods Retrospective analyses were performed on patients who underwent endoscopic surgical resection of TSMs involving the suprasellar region between January 2018 and March 2019. Results Three patients underwent resection of their TSM by the EEA. Tumors in the suprasellar region were completely resected. Patients recovered normally with uneventful postoperative outcomes and were followed-up for at least six months after surgery with no neurological deficits noted. Conclusions The EEA for resection of TSMs is feasible, safe, and effective, with fewer complications and lower mortality than other surgical methods. This a promising surgical approach.

In this work, ternary organic solar cells (OSCs) combining a fullerene derivative PC71BM with a non-fullerene acceptor N2200-F blended with a polymer donor PM6 were reported. Compared with the binary systems, the highest power conversion efficiency (PCE) of 8.11% was achieved in ternary solar cells with 30 wt% N2200-F content, mainly due to the improved short-circuit current density (Jsc) and fill factor (FF). Further studies showed that the improved Jsc could attribute to the complementary absorption of the two acceptors and the enhanced FF was originated from the higher hole mobility and the fine-tuned morphology in the ternary system. These results demonstrate that the combination of fullerene and non-fullerene acceptors in ternary organic solar cells is a promising approach to achieve high-performance OSCs.

A novel coumarin-derived Cu2+-selective Schiff base fluorescent “turn-off” chemosensor CTPE was successfully obtained, which showed an AIE effect. It could identify Cu2+ by quenching its fluorescence. The lower limit of detection was 0.36 μM. CTPE can act as a highly selective and sensitive fluorescence probe for detecting Cu2+.