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Compared with the thiophene-based acceptor, the pyrrole-based acceptor exhibits a strong red-shift and the related device efficiency is significantly improved.

Acceptors (O-IC and O-IC2F) with different terminals have different effects when combined with the donor (D18) to form a device.

It was well known that the “face-on” molecular orientation of acceptors is crucial for efficient charge transport in devices, but less is known about the role of the halogen atoms in controlling the molecular packing. In this article, a set of three acceptor materials with a benzotriazole-based unfused core, coded as BTC6-XF respectively with zero, two and four F atoms on the end groups, were designed and synthesized. Moreover, the effect of halogen atoms on the molecular alignment control was investigated. GIWAXS profiles show that BTC6-0F prefers the edge-on stacking, BTC6-2F adopts the mixed edge-on and face-on packing, and BTC6-4F tends to form the face-on molecular orientation. Additionally, it was found that BTC6-4F possessed more effective carrier transport and less charge recombination than BTC6-0F or BTC6-2F. As a result, the BTC6-4F-based OSC achieved the champion PCE of 11.23% when paired with the polymer donor PBDB-T, while the corresponding BTC6-2F and BTC6-0F based devices respectively gave 10.10% and 8.49% PCEs. This work sheds some light upon the design of small-molecule non-fullerene acceptors for efficient organic solar cells.

Solution-processable organic–inorganic hybrid perovskites are being widely investigated for many applications, including solar cells, light-emitting diodes, photodetectors, and lasers. Herein, we report, for the first time, successful fabrication of xerographic photoreceptors using methylammonium lead iodide (CH3NH3PbI3) perovskite as a light-absorbing material. With the incorporation of polyethylene glycol (PEG) into the perovskite film, the ion migration inherent to the perovskite material can be effectively suppressed, and the resulting photoreceptor exhibits a high and panchromatic photosensitivity, large surface potential, low dark decay, and high environmental resistance and electrical cycling stability. Specifically, the energies required to photodischarge one half of the initial surface potential (E0.5) are 0.074 μJ cm−2 at 550 nm and 0.14 μJ cm−2 at 780 nm, respectively. The photosensitivites outmatch those of the conventionally used organic pigments having narrow spectral responses. Our findings inform a new generation of highly efficient and low-cost xerographic photoreceptors based on perovskite materials.

Organic polymer/inorganic particle composites with thermoelectric (TE) properties have witnessed rapid progress in recent years. Nevertheless, both development of novel polymers and optimization of compositing methods remain highly desirable. In this study, we first demonstrated a simulated in situ coagulation strategy for construction of high-performance thermoelectric materials by utilizing single-walled carbon nanotubes (SWCNTs) and a new D–A polymer TPO-TTP12 that was synthesized via incorporating dioxothiopyrone subunit into a polymeric chain. It was proven that the preparation methods have a significant influence on thermoelectric properties of the TPO-TTP12/SWCNT composites. The in situ prepared composite films tend to achieve much better thermoelectric performances than those prepared by simply mixing the corresponding polymer with SWCNTs. As a result, the in situ compositing obtains the highest Seebeck coefficient of 66.10 ± 0.05 μV K−1 at the TPO-TTP12-to-SWCNT mass ratio of 1/2, and the best electrical conductivity of up to 500.5 ± 53.3 S cm−1 at the polymer/SWCNT mass ratio of 1/20, respectively; moreover, the power factor for the in situ prepared composites reaches a maximum value of 141.94 ± 1.47 μW m−1 K−2, far higher than that of 104.68 ± 0.86 μW m−1 K−2 for the by-mixing produced composites. This indicates that the dioxothiopyrone moiety is a promising building block for constructing thermoelectric polymers, and the simulated in situ compositing strategy is a promising way to improve TE properties of composite materials.

As one of the most attractive inorganics to improve the thermoelectric (TE) performance of the conducting polymers, tellurium (Te) has received intense concern due to its superior Seebeck coefficient (

A practical protocol was disclosed for the nickel-catalyzed C-alkylation of 9-fluorenone hydrazone with alcohols using t-BuOK as the base, and 9-monoalkylated fluorene derivatives were obtained in good yields under the benign conditions.

Organic polymer/inorganic particle composites with thermoelectric (TE) properties have witnessed rapid progress in recent years. Nevertheless, both development of novel polymers and optimization of compositing methods remain highly desirable. In this study, we first demonstrated a simulated

A simple, mild and efficient protocol was developed for the alkylation of fluorene with alcohols in the presence of t-BuOK as catalyst, affording the desired 9-monoalkylfluorenes with near quantitative yields in most cases.

Solution-processed polycrystalline perovskite films have detrimental defects in the bulk and surfaces/grain boundaries, especially the uncoordinated lead ions (Pb2+) with low formation energy, limiting both the performance and stability of the photovoltaic devices. In this work, a conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) is incorporated into a bulk perovskite film by a facile in-situ polymerization method, where 5-bromo-2,3-dihydro-thieno[3,4-b] [1] , [4] dioxine (BEDOT) as monomer is directly added to a perovskite precursor solution and then in-situ polymerized within the perovskite film during the film formation. The PEDOT is chemically anchored at the surface and grain boundaries of the perovskite film via interaction of sulfur and oxygen atoms in PEDOT with uncoordinated lead ions in the perovskite, passivating the surface and bulk defects and also improving the charge extraction efficiency in the solar cell. Moreover, robust and hydrophobic properties of PEDOT can enhance the thermal and moisture resistance of the perovskite film. As a result, a champion power conversion efficiency (PCE) of 22.58% is achieved, along with significantly enhanced environmental, thermal, and light-soaking stability.

Studies have received intense concern on the classical conductive polymers for thermoelectric (TE) materials; but polypyrrole (PPy) seemed to be an exception due likely to its relatively poor TE behaviors. In this work, we present an unconventional two-step electrochemical post-treatment strategy to improve the TE performance of the PPy films electrodeposited, namely first oxidation at + 0.7 V and subsequent reduction at different potentials ranged from − 1.3 to 0 V (vs Ag/Ag+). The doping level of PPy films was regulated accurately by controlling the applied potential. Consequently, the significantly enhanced power factor and figure of merit have been achieved, which are far higher than those of the films obtained via one-step electrochemical post-treatment and hit the records high for the pure PPy. This indicates that the two-step electrochemical post-treatment is a feasible and effective protocol for perfecting thermoelectric performance of polymers, and may be extended to other conducting polymeric systems.

A simple Ni(dppe)Cl2/Ag2O combination has been established as an efficient catalyst system for the homo-coupling of aromatic terminal alkynes. Particularly, this reaction proceeds under mild conditions and can be applied to alkynone substrates. Various aromatic 1,3-diynes were obtained in good to excellent yields.

A nickel-based catalyst was employed in the cross-coupling of carboxylic anhydrides with arylboronic acids, and the reaction was carried out under mild conditions. This new protocol provides an efficient, cheap and convenient alternative to synthesizing aromatic ketones.

A nickel-catalyzed method for the cross-coupling of benzophenone hydrazone with aryl bromides is described. The use of a simple Ni(II)/NHC catalyst leads to the arylated hydrazones in good or acceptable yields. This protocol provides a simple, convenient alternative to the synthesis of arylhydrazines.

A copper-catalyzed C–N coupling reaction is described for the preparation of pyridine-2-carbaldehyde N,N-diarylhydrazones by the arylation of N-mono- or -non-substituted hydrazones with aryl bromides/iodides, and the subsequent conversion of the hydrazones into N,N-diarylhydrazines by a transimination process with an aqueous solution of H2NNH2. The reaction features the use of CuI as the catalyst without the need for external ligands. This methodology provides a convenient alternative to the synthesis of structurally diverse N,N-diarylhydrazines from simple, easily accessible precursors.

A simple and easily-used NiII complex, Ni(PPh3)2(1-naphthyl)Cl, was employed as a pre-catalyst in the Suzuki–Miyaura cross-coupling of benzylic pivalates with arylboronic acids, affording various tri- or diarylmethanes in good yields under mild conditions. This new protocol provides a cheap, convenient and practical alternative to synthesizing multiaryl methanes.

Room-temperature Suzuki―Miyaura aryl―aryl cross-coupling reactions have been achieved in high yields by using an easily accessible, air-stable Ni II ―(σ-aryl) complex as precatalyst without either the pretreatment of organometallic reagents or the presence of external reductants. The Ni II complex, in conjunction with monophosphane ligands such as PCy 3 ·HBF 4 or PPh 3 , allowed the efficient cross-coupling of aryl sulfonates (OTs, OMs) and/or halides (Cl, Br, I) with arylboronic acids at room temperature in toluene/water in the presence of K 2 CO 3 as base.

A practical, efficient protocol was developed for the Suzuki reaction of aryl tosylates with arylboronic acids. The process was promoted by a nickel-based catalyst system consisting of the easily available Ni II -(σ-aryl) complex and the simple ligand PPh 3 in toluene in the presence of the base K 2 CO 3 . The convenient operation, high yield, generality, and low cost make this method viable for most common laboratories and applicable in large-scale preparations.

Objective The aim of this study is to determine the effects of aromatic acids on stimulating blood circulation and removing blood stasis. Methods A systematic study of aromatic acids concentration in the herbs frequently used in Traditional Chinese Medicine (TCM) formula to stimulate blood circulation and remove blood stasis is performed to help to establish a bio-activity basis and a compatibility principle for TCM formula. Results Through the study, we find that aromatic acids' effect of stimulating blood circulation and removing blood stasis may be increased by combing with alkali. Besides, aromatic acid esters can better stimulate blood circulation and remove blood stasis. What's more, the solubilization of aromatic acids helps stimulating blood circulation and removing blood stasis. Conclusions Aromatic acids have been proved to be effective in preventing platelet aggregation and anti-thrombus. On the one hand, they have a biological contribution to TCM formula and on the other hand they improve blood circulation through working with other elements in the TCM formula. Aromatic acids make a lot of contributions to the whole TCM formula.

The synthesis, crystal structures and photophysical properties of a series of cycloplatinated complexes are presented. The complexes have the general formula (C∧N)Pt(O∧O), where O∧O is acetylacetonate and C∧N represents 2-arylimidazoline ligands. All of them are luminescent in CH2Cl2 solution at room temperature. Different aryl group on N-1 of the ligand has no significant effect on the emission properties of the platinum complexes. While introducing alkyl group on N-1 or electron-donating group on 2-aryl ring does result in a blue shift of emission maxima or even an increase in emission intensity.

Aromatic ketones (III) (27 examples) are efficiently and conveniently synthesized by the title reaction.

A nickel-catalyzed method for the cross-coupling of benzophenone hydrazone with aryl bromides is described. The use of a simple Ni(II)/NHC catalyst leads to the arylated hydrazones in good or acceptable yields. This protocol provides a simple, convenient alternative to the synthesis of arylhydrazines.

Triarylamines are prepared from aryl chlorides and diarylamines in the presence of Ni-catalyst and iPrMgCl in moderate to good yields.

A copper-catalyzed C–N coupling reaction is described for the preparation of pyridine-2-carbaldehyde N,N-diarylhydrazones by the arylation of N-mono- or -non-substituted hydrazones with aryl bromides/iodides, and the subsequent conversion of the hydrazones into N,N-diarylhydrazines by a transimination process with an aqueous solution of H2NNH2. The reaction features the use of CuI as the catalyst without the need for external ligands. This methodology provides a convenient alternative to the synthesis of structurally diverse N,N-diarylhydrazines from simple, easily accessible precursors.

The air-stable Ni(II)—(σ-aryl) complex NIC in conjunction with monophosphane ligands efficiently catalyzes the cross-coupling of arylsulfonates (OTos, OMes) and/or halides (Cl, Br, I).

A practical, efficient protocol was developed for the Suzuki reaction of aryl tosylates with arylboronic acids. The process was promoted by a nickel-based catalyst system consisting of the easily available Ni II -(σ-aryl) complex and the simple ligand PPh 3 in toluene in the presence of the base K 2 CO 3 . The convenient operation, high yield, generality, and low cost make this method viable for most common laboratories and applicable in large-scale preparations.

A combination of cupric bromide and Oxone® serves as a facile, mild and effective reagent for the bromination of aromatic amines. Primary, secondary and tertiary aromatic amines are all suitable substrates. The reaction possesses high regioselectivity and functional group tolerance, and mono- and multi-brominated products can be obtained controllably in moderate to excellent yields.