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Pd-catalyzed C-H (hetero)arylation methodology has been optimized for the efficient synthesis of various useful end-capping groups that are widely applied in small-molecule optoelectronic materials. We report herein the synthesis of a broad scope of target molecules ranging from donor-type through acceptor-type to hybrid-type end-capping groups. To demonstrate their application in dye-sensitized solar cells, we have designed two new D-A-p-A'-type organic sensitizers (CYL-3 and CYL-4), which were synthesized in a step-economic manner by sequential C-H arylations using the facilely obtained end-capping groups. The devices based on CYL-3 and CYL-4 give Voc values of 0.67-0.71 V, Jsc values of 10.07-11.63 mA cm-2, and FF values of 70.6-72.9%, which correspond to overall power conversion efficiencies of 4.76-6.02%. This work is expected to become a practical synthetic alternative allowing materials scientists to access small-molecule organic materials in fewer synthetic transformations. [ABSTRACT FROM AUTHOR]

Two low-symmetry phthalocyanines (Pcs) substituted with thiophene units at the non-peripheral (α) and peripheral (β) positions were synthesized and their optical, electronic-structure, and electrochemical properties were investigated. The substitution of thiophene units at the α positions of the phthalocyanine skeleton resulted in a red shift of the Q band and significantly modified the molecular-orbital electronic distributions just below the HOMO and just above the LUMO, with distortion of the typical Gouterman four-orbital arrangement of MOs. Two amphiphilic Ω-shaped ZnPcs ( αPcS1 and αPcS2) bearing a π-conjugated side chain with an adsorption site at an α position of the Pc macrocycle were synthesized as sensitizers for dye-sensitized solar cells (DSSCs). The absorption spectra of αPcS1 and αPcS2 showed red shifted Q bands and a broad band from 350 to 550 nm assignable to the intramolecular charge-transfer transition from the ZnPc core to the side chains. Time-dependent DFT calculations provided a clear interpretation of the effect of the thiophene conjugation on the typical phthalocyanine core π MOs. Compound αPcS1 was used as a light-harvesting dye on a TiO2 electrode for a DSSC, which showed a panchromatic response in the range 400-800 nm with a power conversion efficiency of 5.5 % under one-sun conditions. [ABSTRACT FROM AUTHOR]

A class of dinuclear alkynylplatinum(II) terpyridine complexes has been successfully synthesized and characterized, and their photophysical, electrochemical and excited state properties have been revealed. These dinuclear alkynylplatinum(II) terpyridine complexes have been shown to serve as photosensitizers in light-harvesting processes. [ABSTRACT FROM AUTHOR]

Carbon quantum dots (CQDs) have been incorporated as a sensitizer into TiO2 films to regulate the light-induced cell-detachment performance. Depending on the amount of CQDs incorporated, nanodots or porous films are obtained. It was found that the right amount of CQDs incorporation significantly improves the cell-sheet detachment efficiency, and an intact cell sheet could be obtained after merely five minutes of UV illumination (365 nm, UV365), which is much faster than that from CQDs-free TiO2 film. Furthermore, cell sheets on CQDs-sensitized TiO2 films show improved viability, and alkaline phosphatase and collagen I activity either before or after light-induced detachment. The improved cell-detachment performance is ascribed to the effective inhibition of charge recombination of the TiO2 film and the microstructure variations, which increase the negative surface potential and change the secondary structure of the adsorbed extracellular protein molecules; this results in a faster release of cells. It is suggested that the faster release reduces the possible detrimental impact on cell functions during detachment and helps in maintaining the excellent cellular activity. This study demonstrates that CQDs sensitization is an effective approach for optimizing the performance of light-induced cell-sheet harvest. [ABSTRACT FROM AUTHOR]

The production of hydrogen from sunlight and water is finding an increasingly important role in the production of clean fuels from sustainable and abundant energy sources. In this process, commonly referred to as artificial photosynthesis, the role of the dye sensitizer is critical for optimizing the harvesting of visible light and triggering the reduction reaction at the catalytic active site. In recent decades organometallic sensitizers have mainly been studied, often requiring the use of scarce and, in some cases, toxic elements. This microreview describes the state of the art in the use of metal-free organic sensitizers, highlighting advantages over their organometallic counterparts. The main design and synthetic strategies, specific properties, and device performances are presented. Thanks to recent advances and lower manufacturing costs, organic sensitizers seem set to be of increasing importance for next-generation clean fuels. [ABSTRACT FROM AUTHOR]

Photoelectrochemical water splitting is a promising and environmentally friendly route for the conversion of solar energy into hydrogen. However, the efficiency of this energy conversion process is low because of the limited light absorption and rapid bulk recombination of charge carriers. In this study, the combination of a novel ternary sensitizer AgFeS2, having a narrow bandgap of 0.9 eV, with a BiVO4 electrode is presented for the enhancement of the solar-energy-to-hydrogen conversion efficiency. The photoelectrochemical properties of this combined material were investigated and the photocurrent densities of AgFeS2-BiVO4 composite electrodes were greatly enhanced compared with pristine BiVO4 (15 times higher at 0.6 V vs. Ag/AgCl under AM 1.5G illumination). The enhanced photoelectrochemical properties arise from extended light absorption, fast charge transfer and appropriate energy gap alignment. It was demonstrated that AgFeS2 nanowires are promising inorganic sensitizers for improving the efficiency of solar water splitting. [ABSTRACT FROM AUTHOR]

Cocamidopropyl betaine (CAPB) is a common surfactant widely used in personal care products. Dimethylaminopropylamine (DMAPA) and lauramidopropyldimethylamine (LAPDMA) are two chemicals present as impurities in CAPB and have been reported as skin sensitizers. A rapid and sensitive ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC–MS/MS) method, using a core shell hydrophilic interaction liquid chromatography (HILIC) column, has been developed to quantify DMAPA and LAPDMA in cosmetic products. Corresponding stable isotopically labeled analogues of the above native compounds were used as internal standards to compensate for matrix effect and for loss of recovery. Each sample was first screened to determine whether the sample needed to be diluted to minimize matrix effects as well as to fit the calibration range. The concept of matrix effect factor (MEF) was introduced to quantitatively evaluate each sample with a unique matrix using the internal standards. Recoveries at three spiking levels of low, medium, and high concentrations ranged from 98.4 to 112% with RSDs less than 5%. This method has been validated and is the first UHPLC–MS/MS method, which uses core shell HILIC column and stable isotopically labeled internal standards to simultaneously determine these two CAPB impurities in cosmetic products. [ABSTRACT FROM AUTHOR]

Subporphyrinatoboron(III) (SubB) sensitizers were synthesized for use in dye-sensitized solar cells (DSSCs). The prototype, which comprises a sterically demanding 3,5-di- tert-butylphenyl scaffold, a meso-ethynylphenyl spacer, and a cyanoacrylic acid anchoring group, achieved an open-circuit voltage VOC of 836 mV, short-circuit current density JSC of 15.3 mA cm−2, fill factor of 0.786, and a photon-to-current conversion efficiency of 10.1 %. Such astonishing figures suggest that a bright future lies ahead for SubB in the realm of DSSCs. [ABSTRACT FROM AUTHOR]

Aims To investigate the UVB-independent and exogenous indirect photoinactivation of eight human health-relevant bacterial species in the presence of photosensitizers. Methods and Results Eight bacterial species were exposed to simulated sunlight with greatly reduced UVB light intensity in the presence of three synthetic photosensitizers and two natural photosensitizers. Inactivation curves were fit with shoulder log-linear or first-order kinetic models, from which the presence of a shoulder and magnitude of inactivation rate constants were compared. Eighty-four percent reduction in the UVB light intensity roughly matched a 72-95% reduction in the overall bacterial photoinactivation rate constants in sensitizer-free water. With the UVB light mostly reduced, the exogenous indirect mechanism contribution was evident for most bacteria and photosensitizers tested, although most prominently with the Gram-positive bacteria. Conclusions Results confirm the importance of UVB light in bacterial photoinactivation and, with the reduction of the UVB light intensity, that the Gram-positive bacteria are more vulnerable to the exogenous indirect mechanism than Gram-negative bacteria. Significance and Impact of the Study UVB is the most important range of the sunlight spectrum for bacterial photoinactivation. In aquatic environments where photosensitizers are present and there is high UVB light attenuation, UVA and visible wavelengths can contribute to exogenous indirect photoinactivation. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells (DSSCs) have become a topic of significant research in the last two decades because of their scientific importance in the area of energy conversion. Currently, DSSC is using inorganic ruthenium (Ru)-based, metal-free organic dyes, quantum-dot sensitizer, perovskite-based sensitizer, and natural dyes as sensitizer. The use of metal-free, quantum-dot sensitizer, perovskite-based sensitizer, and natural dyes has become a viable alternative to expensive and rare Ru-based dyes because of low cost, ease of preparation, easy attainability, and environmental friendliness. Most of the alternatives to Ru-based dyes have so far proved inferior to the Ru-based dyes because of their narrow absorption bands (Δ λ ≈ 100-250 nm), adverse dye aggregation, and instability. This review highlights the recent research on sensitizers for DSSC, including ruthenium complexes, metal-free organic dyes, quantum-dot sensitizer, perovskite-based sensitizer, mordant dyes, and natural dyes. It also details and tabulates all types of sensitizer with their corresponding efficiencies. Plot of progress in efficiency ( η) of DSSC till date based on different types of sensitizers is also presented. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The synthesis, photophysical and electrochemical properties, and photovoltaic performances in dye-sensitized solar cells (DSSCs) of five new metal-free organic sensitizers with a carbazole moiety as the electron donor are reported. The compounds contain a thiophene at various positions and a cyanoacrylic acid unit as the electron acceptor. The position of the thiophene moiety affected both the photophysical and electrochemical properties, leading to conversion efficiencies of 1.44 to 4.57 % under AM 1.5 solar conditions (100 mW cm-2). The best performance and longest electron lifetime were found when a thiophene was located on both donor and acceptor sites. The DSSC showed a short-circuit current ( Jsc) of 8.59 mA/cm2, an open-circuit photovoltage ( Voc) of 0.75 V, and a fill factor ( FF) of 0.71. The position of the π-conjugated bridges not only affects the absorption spectra and the energy levels of the sensitizers, but also adjusts the electron lifetime. [ABSTRACT FROM AUTHOR]

A series of directly meso- meso-linked Pd-porphyrin oligomers (PdDTP-M, PdDTP-D, and PdDTP-T) have been prepared. The absorption region and the light-harvesting ability of the Pd-porphyrin oligomers are broadened and enhanced by increasing the number of Pd-porphyrin units. Triplet-triplet annihilation upconversion (TTA-UC) systems were constructed by utilizing the Pd-porphyrin oligomers as the sensitizer and 9,10-diphenylanthracene (DPA) as the acceptor in deaerated toluene and green-to-blue photon upconversion was observed upon excitation with a 532 nm laser. The triplet-triplet annihilation upconversion quantum efficiencies were found to be 6.2 %, 10.5 %, and 1.6 % for the [PdDTP-M]/DPA, [PdDTP-D]/DPA, and [PdDTP-T]/DPA systems, respectively, under an excitation power density of 500 mW cm−2. The photophysical processes of the TTA-UC systems have been investigated in detail. The higher triplet-triplet annihilation upconversion quantum efficiency observed in the [PdDTP-D]/DPA system can be rationalized by the enhanced light-harvesting ability of PdDTP-D at 532 nm. Under the same experimental conditions, the [PdDTP-D]/DPA system produces more 3DPA* than the other two TTA-UC systems, benefiting the triplet-triplet annihilation process. This work provides a useful way to develop efficient TTA-UC systems with broad spectral response by using Pd-porphyrin oligomers as sensitizers. [ABSTRACT FROM AUTHOR]

A diiodo distyryl boron dipyrromethene (BODIPY) core was conjugated to two ferrocenyl quenchers through acid-labile ketal and/or thiol-cleavable disulfide linkers, of which the fluorescence and photosensitizing properties were significantly quenched through a photoinduced electron-transfer process. The two symmetrical analogues that contained either the ketal or disulfide linkers could only be activated by a single stimulus, whereas the unsymmetrical analogue was responsive to dual stimuli. Upon interaction with acid and/or dithiothreitol (DTT), these linkers were cleaved selectively. The separation of the BODIPY core and the ferrocenyl moieties restored the photoactivities of the former in phosphate buffered saline and inside the MCF-7 breast cancer cells, rendering these compounds as potential activable photosensitizers for targeted photodynamic therapy. The dual activable analogue exhibited the greatest enhancement in intracellular fluorescence intensity in both an acidic environment (pH 5) and the presence of DTT (4 m m). Its photocytotoxicity against MCF-7 cells also increased by about twofold upon preincubation with 4 m m of DTT. The activation of this compound was also demonstrated in nude mice bearing a HT29 human colorectal carcinoma. A significant increase in fluorescence intensity in the tumor was observed over 9 h after intratumoral injection. [ABSTRACT FROM AUTHOR]

In this work, selective and aerobic photooxidation of a range of aromatic, aliphatic and α,β-unsaturated alcohols to corresponding carbonyl compounds has been performed with tetraphenylporphyrin (HTPP), ClFeTPP and ZnTPP as sensitizers using visible light and in the presence of molecular oxygen in solvent-free conditions. The conversion rates for alcohols oxidations were in the order of free-base porphyrin (HTPP) > metalloporphyrin (ClFeTPP) and (ZnTPP). This method has a wide range of applications, remarkable conversion and product yield in reasonable time, does not include cumbersome work-up, exhibits chemoselectivity, and proceeds under mild reaction conditions. As the matter of oxidation of cycloheptanol and cyclooctanol using HTPP as photosensitizer, the TON reached up to 1686 and 2464, respectively and selectivity more than 99 %. Graphical abstract: [ABSTRACT FROM AUTHOR]

This review focuses on our work on metal-free sensitizers for dye-sensitized solar cells (DSSCs). Sensitizers based on D−A′−π−A architecture (D is a donor, A is an acceptor, A′ is an electron-deficient entity) exhibit better light harvesting than D−π−A-type sensitizers. However, appropriate molecular design is needed to avoid excessive aggregation of negative charge at the electron-deficient entity upon photoexcitation. Rigidified aromatics, including aromatic segments comprising fused electron-excessive and -deficient units in the spacer, allow effective electronic communication, and good photoinduced charge transfer leads to excellent cell performance. Sensitizers with two anchors/acceptors, D(-π-A)2, can more efficiently harvest light, inject electrons, and suppress dark current compared with congeners with a single anchor. Appropriate incorporation of heteroaromatic units in the spacer is beneficial to DSSC performance. High-performance, aqueous-based DSSCs can be achieved with a dual redox couple comprising imidazolium iodide and 2,2,6,6-tetramethylpiperidin- N-oxyl, and/or using dyes of improved wettability through the incorporation of a triethylene oxide methyl ether chain. [ABSTRACT FROM AUTHOR]

A series of indeno[2,1- b]thiophene-containing organic dyes ( IDT1- IDT5) have been synthesized, and their UV/Vis spectra extend beyond 700 nm. These dyes were employed as sensitizers for dye-sensitized solar cells (DSSCs). Among them, dyes IDT3- IDT5 with a thiophene unit conjugated with an anchor have better light harvesting ability and higher JSC values. Dye aggregation contributes substantially to the photocurrent in the near infrared region. The dye IDT5, with chenodeoxycholic acid (CDCA) as the co-adsorbent, has the highest power conversion efficiency (5.06 %) under AM 1.5G simulated sunlight irradiation, which is 68 % of the standard device based on N719 dye. [ABSTRACT FROM AUTHOR]

Polymethine dyes as photosensitizers for dye-sensitized solar cells (DSCs) are reviewed. The review provides a summary of design strategies, the main synthetic routes, and the optical and photovoltaic properties of polymethine dyes applied in hybrid photovoltaics. In particular, we focus on cyanine and squaraine dyes and their structure-properties relationships, highlighting the role of the active molecule design on device performance. [ABSTRACT FROM AUTHOR]

Quantum-dot-sensitized solar cells (QDSCs) are promising solar-energy-conversion devices, as low-cost alternatives to the prevailing photovoltaic technologies. Compared with molecular dyes, nanocrystalline quantum dot (QD) light absorbers exhibit higher molar extinction coefficients and a tunable photoresponse. However, the power-conversion efficiencies (PCEs) of QDSCs are generally below 9.5 %, far behind their molecular sensitizer counterparts (up to 13 %). These low PCEs have been attributed to a large free-energy loss during sensitizer regeneration, energy loss during the charge-carrier transport and transfer processes, and inefficient charge separation at the QD/electrolyte interfaces, and various interfacial engineering strategies for enhancing the PCE and cell stability have been reported. Herein, we review recent progress in the interfacial engineering of QDSCs and discuss future prospects for the development of highly efficient and stable QDSCs. [ABSTRACT FROM AUTHOR]

The report presented details on different types of inhibitors and their localized actions on cells. The review presented details from specific studies conducted in cancer clinical care. The work also presented reviews on the use of inhibitor for other clinical treatments and practices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Five new dysprosium (III) complexes are synthesized using β-ketoester as main ligand and ancillary ligand. • Complexes are analyzed systematically by using CHN, EDAX, IR, NMR, TG-DTG, UV, DR, and PL. • Photoluminescence study as well as color purity and CCT values confirm cool white emission. • The energy transfer mechanism approves the effective complexation of ligands with metal ion. The synthesis of a novel series of five dysprosium complexes is reported in this work. This series contains one binary and four ternary complexes of dysprosium synthesized with chelating bidentate ligand 2-(methacryloxy)ethylacetoacetate and ancillary ligands i.e. neocuproine; 1,10-phenanthroline; 4,4′-dimethyl-2,2′-bipyridyl; 2,2′-bipyridyl and characterized by Fourier transform infrared, elemental analysis, energy dispersive X-ray analysis, ultra-violet visible spectroscopy and proton NMR spectroscopy. Under ultra violet excitation these complexes reveal characteristic bands of blue emission at 485 nm (4F 9/2 →6H 15/2) and yellow emission at 576 nm (4F 9/2 →6H 13/2). The theoretical values of band gap are obtained using density functional theory which are resembles with experimentally obtained values. Further, their superior practicability in white organic light emitting diodes (WOLEDs) is authenticated by the color purity, corelated color temperature and Commission International de I'Eclairage 1931 coordinates. The color coordinates are found to be consistent with white light coordinates of "National Television System Committee". [ABSTRACT FROM AUTHOR]

Two fused-thiophene-containing ruthenium sensitizers, [Ru(Hdcbpy)(ottip)(NCS)2]- ·0.5[H]+ ·0.5[N(C4H9)4]+ [ Z1, H2dcbpy = 4,4′-dicarboxy-2,2′-bipyridine, ottip = 2-(5-octylthieno[3,2- b]thiophen-2-yl)-1 H-imidazo[4,5- f][1,10]phenanthroline] and [Ru(Hdcbpy)(odttip)(NCS)2]- ·0.5[H]+ ·0.5[N(C4H9)4]+ { Z2, odttip = 2-[6-octyldithieno(3,2- b:2′,3′)thiophen-2-yl]-1 H-imidazo[4,5- f][1,10]phenanthroline}, were designed for use in dye-sensitized solar cell (DSSC) applications. The fused-thiophene-based Z1 and Z2 have stronger light-harvesting capabilities compared with a non-fused-thiophene analog, [Ru(Hdcbpy)(otip)(NCS)2]- ·0.5[H]+ ·0.5[N(C4H9)4]+ [ JF-2t, otip = 2-(5-octylthiophen-2-yl)-1 H-imidazo[4,5- f][1,10]phenanthroline], and a standard N3 dye. The power-conversion efficiency of the Z1- and Z2-sensitized solar cells were superior (8.70 % and 8.15 %) to JF-2t- and N3-sensitized solar cells (7.85 and 7.40 %, respectively) under standard AM1.5G full sunlight irradiation. The photovoltaic performance of Z1 was better than Z2, primarily owing to the fact that Z1-based cells have a higher level of dye loading and less charge recombination, as seen from the electrochemical impedance spectroscopy data. This study not only demonstrates the excellent power-conversion efficiency of new fused-thiophene ruthenium sensitizers, but also points to the promise that fused-thiophene antennas might be a useful molecule in the engineering of ruthenium dyes for DSSCs. [ABSTRACT FROM AUTHOR]

Two novel branched sensitizers bearing biphenyl or fluorenyl groups as the linking skeleton and triphenylamine-stilbene-thiomethyl benzonitrile as peripheral branches were designed. Strong absorption of light in the UV–vis range ( λ max = 389–397 nm, ε max = 60,200–90,300 M −1 cm −1 ) matched the emission of new light sources, i.e., UV–vis light-emitting diodes at 365–450 nm. The reactive species produced from the photoinitiating systems based on these chromophores themselves or combined with an iodonium salt, N-vinylcarbazole, or an amine were highly efficient for versatile photopolymerizations (radical, cationic, and thiol-ene polymerizations) upon soft exposure conditions (365–450 nm light-emitting diodes). The UV–vis spectra, theoretical calculation of molecular orbitals, electrochemistry, and fluorescence quenching measurements were studied to reveal the photochemical mechanism. [ABSTRACT FROM AUTHOR]

Catalysis is a topic of continuous interest since it was discovered in chemistry centuries ago. Aiming at the advance of reactions for efficient processes, a number of approaches have been developed over the last 180 years, and more recently, porphyrins occupy an important role in this field. Porphyrins and metalloporphyrins are fascinating compounds which are involved in a number of synthetic transformations of great interest for industry and academy. The aim of this review is to cover the most recent progress in reactions catalysed by porphyrins in scalable procedures, thus presenting the state of the art in reactions of epoxidation, sulfoxidation, oxidation of alcohols to carbonyl compounds and C–H functionalization. In addition, the use of porphyrins as photocatalysts in continuous flow processes is covered. [ABSTRACT FROM AUTHOR]

Three new d10 transition-metal dithiocarbamates containing ferrocene, namely [M(FcCH2EtOHdtc)2] (M = Zn, Cd and Hg; dtc = dithiocarbamate) have been synthesized and characterized by elemental analyses, IR, 1H, and 13C NMR spectroscopy, and X-ray crystallography. The coordination geometries around the zinc and mercury ions in the complexes are distorted tetrahedral and distorted linear, respectively. The distorted linear geometry around the mercury complex can be attributed to the presence of the bulky methylferrocenyl groups. These complexes have been used in dye-sensitized solar cells (DSSCs) as co-sensitizers and co-adsorbents. The assembly fabricated by using the zinc complex and N719 (Zn/N719) showed the best performance with an overall photon-to-current conversion efficiency (PCE) of 7.10 ± 0.02 %, which is an improvement of 23 % in the cell performance compared with the DSSC fabricated by using N719 (PCE 5.76 ± 0.04 %) alone under identical conditions. [ABSTRACT FROM AUTHOR]

A new additional benzothiazole (BT) acceptor has been introduced into metal-free organic dyes ( MCG1- MCG4) to construct donor-acceptor-π-acceptor (D-A-π-A) architecture with the systematic replacement of diheteroanthracene donors and heteroaromatic π-bridge components. BT not only facilitates effective electron transfer from the donor to the anchoring group, but also lowers the band gap. The planarity of the sensitizers induces J aggregation on TiO2, causes the redshift on TiO2, and enhances the light-harvesting efficiency up to λ=750-800 nm. Transient absorption spectroscopy and electrochemical impedance spectroscopy have been used to understand the trends in short-circuit current ( Jsc) and open-circuit voltage ( Voc). Dye MCG4 showed a superior efficiency of 6.46 %. DFT has been complemented with experimentally determined photoelectrochemical properties. These molecules are new and support π-bridge extension with BT for better performance of D-A-π-A organic sensitizers. [ABSTRACT FROM AUTHOR]