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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.

Tin-based halide perovskite materials have been successfully employed in lead-free perovskite solar cells, but the overall power conversion efficiencies (PCEs) have been limited by the high carrier concentration from the facile oxidation of Sn2+ to Sn4+ . Now a chemical route is developed for fabrication of high-quality methylammonium tin iodide perovskite (MASnI3 ) films: hydrazinium tin iodide (HASnI3 ) perovskite film is first solution-deposited using presursors hydrazinium iodide (HAI) and tin iodide (SnI2 ), and then transformed into MASnI3 via a cation displacement approach. With the two-step process, a dense and uniform MASnI3 film is obtained with large grain sizes and high crystallization. Detrimental oxidation is suppressed by the hydrazine released from the film during the transformation. With the MASnI3 as light harvester, mesoporous perovskite solar cells were prepared, and a maximum power conversion efficiency (PCE) of 7.13 % is delivered with good reproducibility.

Electron acceptors with nonfused aromatic cores (NCAs) have aroused increasing interest in organic solar cells due to the low synthetic complexity and flexible chemical modification, but the corresponding device performance still lags behind. Herein, we designed and synthesized two new quinoxaline-based NCAs, namely, QOC6-4H and QOC6-4Cl. Although both NCAs show good backbone coplanarity, QOC6-4Cl with chlorinated end groups exhibits higher extinction coefficient, enhanced crystallinity, and more compact π-π stacking, which is correlated with the stronger intermolecular interactions induced by chlorine atoms. Benefiting from the broader and stronger optical absorption, improved carrier mobilities, and suppressed charge recombination, a notable power conversion efficiency (PCE) of 12.32% with a distinctly higher short-current density (Jsc) of 22.91 mA cm-2 and a fill factor (FF) of 69.01% could be obtained for the PBDB-T:QOC6-4Cl-based device. The PCEs of PBDB-T:QOC6-4H were only lower than 8%, which could mainly be attributed to the unsymmetric charge transport. Our work proves that the chlorination of end groups is a facile and effective strategy to enhance the intermolecular interactions and thus the photovoltaic performance of NCAs, and a careful modulation of the intermolecular interactions plays a vital role in further developing both high-performance and low-cost organic photovoltaic 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

Defects from grain interiors and boundaries of perovskite films cause significant nonradiative recombination energy loss, and thus perovskite films with controlled crystallinity and large grains is critical for improvement of both photovoltaic performance and stability for perovskite-based solar cells. Here, a methylamine (MA0) gas-assisted crystallization method is developed for fabrication of methylammonium lead iodide (MAPbI3) perovskite films. In the process, the perovskite film is formed via controlled release of MA0 gas molecules from a liquid intermediate phase MAPbI3·xMA0. The resulting perovskite film comprises millimeter-sized grains with (110)-uniaxial crystallographic orientation, exhibiting much low trap density, long carrier lifetime, and excellent environmental stability. The corresponding perovskite solar cell exhibits a power conversion efficiency (PCE) of ~ 21.36%, which is among the highest reported for MAPbI3-based devices. This method provides important progress towards the fabrication of high-quality perovskite thin films for low-cost, highly efficient and stable perovskite solar cells., Suppressing grain boundaries and defects in perovskite solar cells remains a quest to address the efficiency and stability issues. Here, the authors use methylamine gas for assisting the growth of uniaxial-oriented perovskite thin films with millimeter-sized grains.

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.

There has been growing interest in the effectual strategy of constructing non-fullerene acceptors for organic solar cells that may overcome the defect of traditional fullerene-based acceptors. Herein, two novel push–pull (acceptor–donor–acceptor) type small-molecule acceptors, that is, TPA-PDI2 and TPA-PDI3, with triphenylamine (TPA) as the core unit and pyran-annulated perylene diimides (Py-PDIs) as peripheral groups are designed and synthesized for non-fullerene organic solar cells (OSCs). After device optimization, OSCs based on TPA-PDI3 demonstrate good device performance with a power conversion efficiency (PCE) as high as 5.84%, surpassing the TPA-PDI2-based counterparts fabricated under identical conditions (1.314% PCE). The high efficiency for TPA-PDI3 can be attributed to the complementary absorption spectra with the donor material (PBDB-T), balanced carrier transport and favorable morphologies. To the best of our knowledge, this PCE of 5.84% is among the highest values based on ethynyl-functionalized TPA-shaped non-fullerene acceptors so far.

We report two new propeller-shaped perylene diimide (PDI) acceptors based on tetraphenylethylene (TPE) as the core and flanked with S/Se-fused PDIs, named as TPE-PDI4-S and TPE-PDI4-Se. Compared to the sulfur-annulated counterpart, TPE-PDI4-Se exhibits a blue-shifted absorption spectrum, stronger absorption in the region of 400–600 nm, higher LUMO energy level and twisted molecular geometry. The TPE-PDI4-Se based device with PBDB-T1 as the donor achieved a power conversion efficiency (PCE) of 7.63% along with a high VOC of 1.08 V, a JSC of 10.28 mA cm−2 and a high fill factor of 68.8%, a 11.4% boost in PCE with respect to the TPE-PDI4-S based control device (6.85%). The high photovoltaic performance of the TPE-PDI4-Se based device can be attributed to its relatively high-lying LUMO level, complementary absorption spectra with the donor material, relatively favorable morphology and balanced carrier transport. To the best of our knowledge, a PCE of 7.63% is among the highest values for TPE core-based non-fullerene organic solar cells. Overall, our work provides a simple and effective molecule-designing method to promote the PCE of non-fullerene OSCs.

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.

The low toxicity, narrow bandgaps, and high charge‐carrier mobilities make tin perovskites the most promising light absorbers for low‐cost perovskite solar cells (PSCs). However, the development of the Sn‐based PSCs is seriously hampered by the critical issues of poor stability and low power conversion efficiency (PCE) due to the facile oxidation of Sn2+ to Sn4+ and poor film formability of the perovskite films. Herein, a synthetic strategy is developed for the fabrication of methylammonium tin iodide (MASnI3) film via ion exchange/insertion reactions between solid‐state SnF2 and gaseous methylammonium iodide. In this way, the nucleation and crystallization of MASnI3 can be well controlled, and a highly uniform pinhole‐free MASnI3 perovskite film is obtained. More importantly, the detrimental oxidation can be effectively suppressed in the resulting MASnI3 film due to the presence of a large amount of remaining SnF2. This high‐quality perovskite film enables the realization of a PCE of 7.78%, which is among the highest values reported for the MASnI3‐based solar cells. Moreover, the MASnI3 solar cells exhibit high reproducibility and good stability. This method provides new opportunities for the fabrication of low‐cost and lead‐free tin‐based halide perovskite solar cells., Tin fluoride and methylammonium iodide are employed as precursors for the fabrication of methylammonium tin iodide (MASnI3) film via an ion exchange/insertion reactions approach, and a highly uniform, pinhole‐free perovskite film is obtained with a high concentration of SnF2 and a low content of Sn4+. The corresponding solar cell exhibits the highest power conversion efficiency of 7.78% with high reproducibility and stability.

A nickel-based catalyst was employed for the first time in the crossing-coupling of indenoindoles with bromo-/iodoarenes. A simple and practical method was provided for the synthesis of N-aryl substituted indenoindole and the mechanism of this reaction was discussed.

Perylenediimide (PDI) possesses intense absorption, a low-lying energy level, and a high electron mobility. However, its highly planar conformation and thus strong intermolecular π–π stacking prevents its application as an electron acceptor used in efficient bulk heterojunction (BHJ) organic solar cells (OSCs). Herein, we report a structurally non-planar molecule TRIP-PDI3, in which a rigid and shape-persistent triptycene (TRIP) unit is employed as a central unit to collect three PDI arms at the periphery. As an electron acceptor, TRIP-PDI3 exhibits a low-lying LUMO energy level of −3.81 eV similar to that of conventional PCBM, but with an intensive light absorption in the range of 450–600 nm. BHJ OSCs were fabricated using TRIP-PDI as an electron acceptor and a low band gap polymer PBDT-TS1 as an electron donor, exhibiting a power conversion efficiency (PCE) of 4.53%. The result demonstrates that TRIP is a promising building block for the construction of structurally non-planar PDI derivatives as non-fullerene (NF) electron acceptors for efficient OSCs.

Methylammonium bismuth iodide (MA3Bi2I9) perovskite, has been deposited on a mesoporous TiO2 film with high homogeneousity and coverage through interdiffusion of solution-processed BiI3/CH3NH3I stacking layers, resulting in higher power conversion efficiency in the perovskite solar cell as compared with that prepared using a conventional one-step solution method.

Currently, the hybrid perovskite solar cells were exclusively dominated by the Pb or Sn-based perovskite materials, and these materials, however, exhibit long term instabilities associated with ambient hydrolysis and oxidation, limiting their widespread applications. In this work, two layered cupric bromide hybrid perovskite compounds are prepared as light absorbers for application in heterojunction solar cells. The perovskite layers can be deposited from the solutions of the as-prepared perovskites or directly from their precursor solutions at ambient condition. Their preliminary phoyovoltaic performance was carried out in mesoporous TiO2 heterojunction solar cells. (c) 2015 Elsevier B.V. All rights reserved.

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.

Two novel donor–acceptor organic dyes (PPL-1 and PPL-2) with pyrazino-[2,3-f][1,10]phenanthroline as an electron-withdrawing anchoring group were designed and synthesized for dye-sensitized solar cells, achieving a promising power conversion efficiency of 4.04% under standard AM 1.5 conditions.

A push–pull thienoquinoidal dye (QT-1), was synthesized as a sensitizer in a p-DSC, giving a high short-circuit photocurrent density of 8.2 mA cm−2. The result would pave new organic semiconductor sensitizers for use in p-DSCs and other organic optoelectronic devices.

Two small molecular quinoidal thiophene dyes, featuring quinoidal thiophene as a spacer, N,N-diethylaniline or N,N-bis(p-methylphenyl)aniline as an electron donor moiety, and dicyanomethylene as an electron acceptor moiety, have been synthesized as donors for organic photovoltaic cells, and a best power conversion efficiency of 5.12% has been achieved.

Three diketopyrrolopyrrole (DPP) dyes ( ICD-3 , ICD-4 and ICD-5 ) with a D-π-A conjugation were designed and synthesized, where a symmetric phenyl-DPP-phenyl unit was used to connect a substituted diphenylamine and a thienyl acrylic acid, and two n -hexyl or 2-ethyl-hexyl chains were introduced on the periphery of the DPP macrocycle. The dyes were characterized by photophysical, electrochemical, and density functional theory calculations. Among the three dyes, the ICD-5 -based DSC afforded the best photovoltaic performance: a short circuit photocurrent density ( J sc ) of 16.34 mA/cm 2 , an open circuit voltage ( V oc ) of 753 mV, and a fill factor ( FF ) of 0.74, corresponding to an overall conversion efficiency ( η ) of 9.10% using I − / I 3 − redox couple-based liquid electrolyte under AM 1.5 conditions. The experimental results demonstrate that the DPP-based sensitizer is a promising option for DSCs, and rational molecular engineering is crucial for constructing highly efficient charge transfer sensitizers.

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.

Two asymmetric DPP dyes with a D–π–A structure are reported, where DPP is used as a bridge to connect the triphenylamine donor and cyanoacetic acid acceptor. The compact dyes exhibit high light absorption ability covering the whole visible spectral region. The most efficient cell exhibited a short-circuit current density of 17.72 mA cm−2, an open-circuit voltage of 725 mV, and a fill factor of 74%, yielding a power conversion efficiency of 9.51% under standard test conditions (irradiation of 1000 W m−2, air mass = 1.5 G), which is the highest value reported for DPP-based DSCs employing an I−/I3− redox couple. Furthermore, the DPP dyes show remarkable stability under long-term irradiation over 1000 h. Considering the facile synthesis and excellent stability, the DPP sensitizer would be a promising option for highly efficient DSCs. The results show that judicious molecular engineering is crucial for constructing highly efficient charge transfer sensitizers in DSCs.

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.

Pyrazino[2,3-g]quinoxaline was first employed as a π-linker in D–π–A type dyes, exhibiting an unusually broad and intense spectral absorption ranged from the visible to the near infrared region. A power conversion efficiency of 6.86% was achieved in dye-sensitized solar cells.

Electromer is a unique excited-state species which can only be formed under electrical excitation. Currently, a clear understanding of electromer has not been realized yet. A big obstacle is that the electromer emission can hardly be separated from the emission of molecular excitons. Obtaining a complete electromer emission is essential for photophysical investigations of this kind of excited-state species and is useful for its potential application in optoelectronic logic gates. We report that a complete electromer emission can be achieved by introduction of a weak-fluorescence layer in organic light-emitting diodes, which will quench the molecular excitons produced in the adjacent emissive layer but leave the electromers undisturbed. In addition, a possible mechanism for the electromer formation is proposed based on the analysis of the single crystal structure of the compound 9,9-bis[4-(di-p-tolyl)aminophenyl]-2,7-bis(9-carbazolyl)fluorene which can produce electromers.

Pyrene is an alternant polycyclic aromatic hydrocarbon consisting of four fused benzene rings with a large, flat aromatic system, showing high thermal stability, extensive electron delocalization and electron accepted nature. In this work, pyrene was firstly employed as π-conjugated bridge to construct electron donor–π–electron acceptor (D–π–A) organic dyes, where diarylamine or indoline was used as donor, and cyanoacrylic acid as electron acceptor. The peryne-based dyes were employed as sensitizers in dye-sensitized solar cells, and give a short circuit photocurrent density (Jsc) of 12.1 mA/cm2, an open circuit voltage (Voc) of 0.71 V, and a fill factor (FF) of 0.71, corresponding to an overall conversion efficiency (η) of 6.1% under AM 1.5 conditions.

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.

Dye-sensitized photoelectrochemical solar cells (DSCs) are one of the most promising alternatives to conventional inorganic devices owing to their potential low production costs and high conversion efficiencies. In a typical DSC, a mesoporous n-type TiO2 electrode, anchored with an electron-injecting sensitizer, acts as an photoanode for light absorption, and a platinized fluorine-doped tin oxide (FTO) glass as a passive cathode for catalysis of the electrolyte with a redox couple I /I3 , sandwiched between the two electrodes (n-DSC). In this n-DSC, light-induced electron injection from the excited sensitizer into the conduction band of TiO2 is followed by hole injection into the electrolyte, generating a photovoltage defined by the difference in chemical potential between the TiO2 photoanode and the electrolyte. On the other hand, a p-type semiconductor electrode (such as NiO) can be sensitized by a hole-injection sensitizer and used as a photocathode in combination with a Pt passive anode in a DSC (p-DSC). In this case, an opposite process occurs, with electron injection into the electrolyte and hole injection into the valence band of NiO, resulting in a photovoltage equal to the difference in chemical potential between the NiO photocathode and the electrolyte. With the combination of a photoanode and a photocathode in a single device (np-DSC), a tandem DSC has been advanced with a theoretical efficiency limitation well beyond that of a single junctionDSC (nor p-DSC). In this double junction tandem device, both the active electrodes are connected in series, and thus a high photovoltage, namely a sum of the photovoltages obtained in the corresponding p and n devices, can be expected, with the potential to dramatically improve the efficiency. Since the first report in 2000, the p-type NiO semiconductor has been extensively investigated, and efforts were mainly focused on the development of hole injection sensitizers for the electrode. In most reports, the NiO based pDSCs gave the very limited photocurrent densities of 1– 2 mAcm 2 and low open-circuit voltages Voc of typically < 150 mV, resulting in efficiencies of < 0.2%. Recently, a record conversion efficiency of 0.41% was achieved in a pDSC through a combinational optimization of NiO electrode, electrolyte, and sensitizer. The efficiency is encouraging, but is still low owing to the intrinsic limitation of the NiO electrode, where 30–40% of photons are absorbed by the NiO electrode itself, but made almost no photocurrent contribution to the device. Furthermore, the Voc is also limited by its high positive valence band energy level. Thus, it is necessary to develop new photocathodes to further improve the efficiency of the tandem device. Most recently, an acidtreated CdS quantum-dot-based electrode was reported as a photocathode, giving a photocurrent density (Jsc) of 0.1 mAcm 2 and open-circuit voltage of 111 mV. Herein, we present a selenium-based photocathode that was developed by deposition of selenium on the TiO2 electrode by an electrochemical deposition method. With this photocathode, a photoelectrochemical solar cell was prepared using a Pt counter electrode and a standard I /I3 electrolyte, exhibiting a cathodic photocurrent of 3.73 mAcm , an open-circuit voltage (Voc) of 318 mV, and an overall efficiency of 0.34% under AM1.5 (100 mWcm ) illumination. A tandem device was further constructed by replacing the Pt counter electrode with a conventional N719sensitized TiO2 anode, giving a Jsc of 2.72 mAcm , a Voc of 940 mV, and an overall efficiency of 0.98%. The tandem device is represented with an energy scale in Figure 1. For the preparation of the selenium-based photocathode, a 2.4 mm-thick porous TiO2 layer was firstly coated on a FTO glass substrate by the doctor blade technique with TiO2 paste (particle size 60 nm) synthesized according to a previous report. Then a thin selenium layer on the mesoporous TiO2 electrode was obtained by the electrochemical deposition method, which was widely used owing to its simplicity, good reproducibility, and controllable deposition fashion. Elemental selenium was deposited inside the mesoporous TiO2 film by reduction of selenite ions

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.