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Nanosize CdS and TiO2 sol were prepared by precipitation reaction of Cd(NO3)2 and Na2S aqueous solutions and by sol–gel reaction of Ti alkoxide, respectively. They were mixed together mechanically with variation of the mole ratio (r) of TiO2/(CdS+TiO2). Then, the CdS−TiO2 mixed sols were further treated with the hydrothermal processing at the temperatures of 120–240°C. CdS–TiO2 composite particulate films were thus prepared by casting the resulting sol onto F:SnO2 conducting glass and a subsequent heat-treatment at 400°C under air. Again, the physical properties of these films were controlled by the surface treatment with TiCl4 aqueous solution. With the hydrothermal treatment, the crystallinity of both CdS and TiO2 particles increased, and CdS particles were seen to be surrounded homogeneously by TiO2 particles. Hydrogen photo-production rates measured under the present experimental conditions varied according to the mole ratio (r) and showed the maximum value at r=0.8, which were in consistent with the photocurrent trend of the composite films, suggesting the importance of effective distribution and contacts among the particles. Also, the film surface treatment with TiCl4 aqueous solution caused a considerable improvement in photocatalytic activity and photocurrent of the films, probably as a result of closer contacts between the primary particles by the etching effect of TiCl4. [Copyright &y& Elsevier]

Abstract: A series of quinoxaline (Qx)-based copolymers, poly[2,7-(9,9-bis(2-ethylhexyl)dibenzosilole)-alt-5,5-(5′,8′-di-2-thienyl-2,3-bis(4-octyloxyl)phenyl)quinoxaline] (P1), poly[4,8-bis(2-ethylhexyloxy)benzo[1,2-b:4,5-b′]dithiophene-alt-5,5-(5′,8′-di-2-thienyl-2,3-bis(4-octyloxyl)phenyl)quinoxaline] (P2), and poly[4,4′-bis(2-ethylhexyl)-dithieno[3,2-b:2′,3′-d]silole-alt-5,5-(5′,8′-di-2-thienyl-2,3-bis(4-octyloxyl)phenyl)quinoxaline] (P3), were synthesized and characterized for use in polymer solar cells (PSCs). We describe the effects of the various donor segments on the optical, electrochemical, field-effect carrier mobilities, and photovoltaic characteristics of the resulting Qx-based copolymers. The results indicated that the donor units in the copolymers significantly influenced the band gap, electronic energy levels, carrier mobilities, and photovoltaic properties of the copolymers. The band gaps of the copolymers were 1.71–2.03eV. Under optimized conditions, the Qx-based polymers showed power conversion efficiencies for the PSCs of 0.87–2.15% under AM 1.5 illumination (100mW/cm2). Among the studied Qx-based copolymers, P2, which contained a benzo[1,2-b:4,5-b′]dithiophene unit, showed a power conversion efficiency of 2.15% with a short circuit current of 7.06mA/cm2, an open-circuit voltage of 0.67V, and a fill factor of 0.46, under AM 1.5 illumination (100mW/cm2). [Copyright &y& Elsevier]

Abstract: A new series of fullerene (C60) multiadducts of methyl ester substituted thieno-o-quinodimethane were synthesized for polymer solar cells (PSCs). The synthesized 5-methyl ester thieno-o-quinodimethane fullerene (C60) multiple adducts, such as METFMA (mono-adduct), METFBA (bis-adduct) and METFTA (tris-adduct), showed good solubility in toluene, CHCl3 and ODCB. Their molecular structures were confirmed by 1H, 13C NMR, UV–visible spectroscopy, DSC, TGA and HRMS Cyclic voltammetry revealing a lowest unoccupied molecular orbital (LUMO) energy level of −3.65eV for METFMA, −3.53eV for METFBA and −3.42eV for METFTA, which is higher than that of PC61BM. The higher LUMO energy level of METFMA, METFBA and METFTA resulted in an enhancement of the open-circuit voltages (V oc) of PSCs. Device of the multiple adduct acceptors was blended with a P3HT donor with the configuration, ITO/PEDOT/P3HT:acceptor/LiF/Al, using METFMA, METFBA, METFTA and PC61BM as the electron acceptor. The optimal photovoltaic performances were achieved using METFBA and METFTA with power conversion efficiencies of 3.00% and 2.93%, respectively. These results were comparable to the device conducted with P3HT:PC61BM (3.42%) under the same conditions. [Copyright &y& Elsevier]

Abstract: A new conjugated polymer containing pentaselenophene (5Se) electron donor moieties was designed for use in polymer solar cells and synthesized via a Stille coupling reaction. The structure, optical properties, electrochemical properties, hole mobility, photovoltaic properties, and AFM morphology of the homopolymer (P5Se) and the donor–acceptor copolymer (P5SeDTDPP) with a diketopyrrolopyrrole (DPP) acceptor were investigated and are discussed. The polymers showed good solubility, film-forming properties, and thermal stabilities. P5Se exhibited a broad absorption across the visible range, 400–700nm, which is a prerequisite for photovoltaic applications. P5SeDTDPP yielded a broader absorption spectrum, enhanced π–π interactions, and a lower band gap compared to P5Se, due to the enhanced intramolecular charge transfer interactions between the donating moiety (pentaselenophene) and the DPP accepting moiety. Solution-processed field effect transistors fabricated from these polymers displayed p-type organic thin film transistor characteristics. P5Se and P5SeDTDPP exhibited typical p-type organic semiconductor characteristics with hole mobilities of 2.3×10−3 and 1.2×10–2 cm2 V−1 s−1, respectively. Photovoltaic devices were fabricated using polymer:PCBM blends in ITO/PEDOT:PSS/blend/Al structures. The P5SeDTDPP device exhibited an open circuit voltage (V OC) of 0.44V, a short circuit current (J SC) of 10.67mA/cm2, a fill factor (FF) of 0.51, and a power conversion efficiency (PCE) of 2.40% under AM 1.5G (100mW/cm2) conditions. [Copyright &y& Elsevier]

Abstract: A new donor unit viz. 3,8-bis(2-butyloctyloxy)naphtho[3,2-b:7,6-b′]dithiophene (NDT) was developed for a novel donor–acceptor semiconducting polymer. And the new NDT-based polymers (PNDTTT-C and PNDTTT-CF) with thienothiophene units were synthesized. The polymers showed deep HOMO levels of −5.44eV and −5.51eV with the optical band gap of ∼1.6eV. The electrochemical as well as optical and photovoltaic properties of these polymers were studied. The OPV devices fabricated from the blends of polymer PNDTTT-C/PNDTTT-CF: PC71BM were afforded a high power conversion efficiency of 4.49% and 5.16%, respectively. The optimization of device fabrication included different solvents, different weight ratios and usage of solvent processing additive. To obtain the high PCE a typical processing additive 1,8-diiodooctane was used. The effect of processing additive was studied using AFM analysis. In addition, the field-effect hole mobilities of 3.5×10−4 cm2V−1s−1 and 5.7×10−4 cm2V−1s−1 were observed for the polymers PNDTTT-C and PNDTTT-CF, respectively. Since we have developed the synthetic process of the 3,8-bis(2-butyloctyloxy)- naphtho[3,2-b:7,6-b′]dithiophene(NDT) monomer, the NDT unit will play an important role in future research on conjugated polymer and small molecule design for high-performance organic semiconducting material. [Copyright &y& Elsevier]

Abstract: Two linear-type π-conjugated small molecules based on thiophene and benzothiadiazole, β -DH5TB(1) and β -DH5TB(2), were synthesized using the Suzuki coupling reaction to have β-substituted solubilizing alkyl groups. The solubility of β -DH5TBs was significantly improved by changing the direction of the alkyl group compared to α-substituted oligothiophene ( α -DH5TB). The relationship between the alkyl substitution pattern and the photovoltaic properties was investigated by measuring the optical and electrochemical properties and the film morphology. Among them, the 4-hexyl substituted β -DH5TB(2) showed the lowest optical band gap and HOMO level together with a red-shifted broad UV absorption. In addition, a high degree of molecular alignment was also observed in β -DH5TB(2), indicative of good charge transport. The β -DH5TB(2) film showed higher field-effect mobility (μFET) of 6.28×10−4 cm2 V−1 s−1 than β -DH5TB(1) film. Owing to the improved solubility, two of the synthesized β -DH5TBs could be used as donor materials in solution-processed organic photovoltaic cells (OPVs), whereas the α -DH5TB:PC71BM blend film showed no photovoltaic properties due to the poor solubility of α -DH5TB. The improved absorption and molecular alignment of the β -DH5TB(2) yielded a device efficiency (0.98%) higher than that of β -DH5TB(1). [Copyright &y& Elsevier]

Abstract: Arylenevinylene based bis(arylhalide) monomers were synthesized as low band gap electron-accepting blocks, and were copolymerized with 9,9-dioctyl-2,7-fluorene or 9-(heptadecan-9′-yl)-2,7-carbazole diboronic esters as electron-donating blocks using Suzuki coupling polymerization. Four alternating copolymers were synthesized through the combination of two different bis(arylhalide)s and diboronic esters, and their optical, thermal and electrochemical properties were characterized. The intra-molecular charge transfer interaction between the electron donating and electron accepting blocks in the polymeric backbone induced a broad absorption from 300 to 650nm. The optical band gap energies of the polymers were measured from their absorption onsets to be 1.97–2.18eV depending on the polymer structure. Bulk heterojunction photovoltaic devices were fabricated using the synthesized polymers as the electron donors and 6,6-phenyl C71-butyric acid methyl ester (PC70BM) as the electron acceptor. One of these devices showed a high power conversion efficiency of 3.22%, with an open-circuit voltage of 0.74V, a short-circuit current of 10.60mA/cm2, and a fill factor of 0.41 under air mass (AM) 1.5 global (1.5G) illumination conditions (100mW/cm2). [Copyright &y& Elsevier]

Abstract: A novel fullerene derivative with an N-hexylphenothiazine moiety, PTZ-C60, was synthesized and characterized. The new synthesized fullerene showed good solubility in common organic solvents such as toluene, chlorobenzene and 1, 2 dichlorobenzene. The synthetic product PTZ-C60 was characterized by 1H and 13C NMR, FT-IR and UV–vis spectroscopy. Photovoltaic devices were fabricated using the new fullerene derivative as the electron acceptor and P3HT as the electron donor. The configuration of the device was as follows: ITO/PEDOT:PSS/active layer/LiF/Al. The weight ratios of the electron donor to the acceptor in the active layer were 1:0.5, 1:0.7, and 1:1. The open-circuit voltage (V oc) of the fabricated devices was found to be higher than that of devices based on C60 because the LUMO energy level of the new fullerene derivative was higher than that of C60. Further, the power conversion efficiency (PCE) of these devices was observed to be high when annealing was carried out at 150°C for 5min and the thickness of the active layer was 80nm. The maximum V oc, short-circuit current density, and PCE of the best device were 0.608V, 4.393mA/cm2, and 1.29%, respectively. [Copyright &y& Elsevier]

Abstract: This article reports our investigation on H2 generation from visible light (λ ≥420nm) photodecomposition of H2S by nanomaterial catalysts, α-Fe2O3 and its chemically modified Fe2−x Ga x O3 (Ga substitution at x =0.6, FeGaO3-I and x =1.0, FeGaO3-II). Simple template-free hydrothermal technique was employed to synthesize the three photocatalysts. XRD study reveals rhombohedral nanocrystalline structure and FESEM shows nanospheres morphology for Fe2O3 and nanosticks/nanorods for both FeGaO3-I, and FeGaO3-II. In H2 generation, Fe2O3 and FeGaO3-II perform moderate and almost same activities in the fresh and used conditions (quantum yield, QY=6.0–6.8% at 550nm). Contrarily, fresh FeGaO3-I exhibits a greater activity (11.2% QY) and the activity is further enhanced (QY=15.3%) on regeneration and reuse. The intricacy, as resolved by XRD and FESEM, appears to take place through morphology transformation. The present work, thus, successfully demonstrates H2 generation from H2S by nanostructured photocatalysts involving morphology dependent activity enhancement. [Copyright &y& Elsevier]

Abstract: Thermally evaporated tungsten oxide (WO3) films are investigated as a buffer layer on anodes to improve the performance of bulk-heterojunction solar cells based on poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61 butyric acid methyl ester (PCBM-60). Characterization of the WO3 film under study shows that it is amorphous with the conductivity on the order of 10−6 S/cm and can effectively planarize an originally rough ITO surface down to the RMS roughness of 0.88nm. Insertion of 5–30nm-thick WO3 layers resulted in power conversion efficiency and fill factor as high as 3.1% and 0.70, respectively, showing an improvement with a good batch-to-batch consistency over conventional cells. The observed improvement is related mainly to the relatively large shunt resistance of WO3-based cells under illumination that is linked to a low carrier recombination resulting in high fill factor and open-circuit voltage. [Copyright &y& Elsevier]

Abstract: We report here the novel approach to synthesis of layer perovskite photocatalysts, Pb2Ga2Nb2O10 and RbPb2Nb2O7 using solid state route (SSR) and molten salt synthesis (MSS) method. The reported modified MSS method has advantage over conventional SSR method for uniform particle size, well-defined crystal structure, controlled morphology and stoichiometry vis-à-vis photocatalysis. The structural study was performed using X-ray difractometry (XRD) and computation based on density functional theory (DFT). The simulation study showed that both the compounds belong to the Ruddlesden-Popper phase (A′2A n−1B n O3n+1; n =2 or 3). The surface morphology of the materials was studied using field emission scanning electron microscope (FESEM) and high resolution transmission electron microscope (HRTEM). The average particles size of perovskites Pb2Ga2Nb2O10 and RbPb2Nb2O7 was in the range 20–40 and 70–90nm respectively. The efficacy of these materials was studied to particle size and morphology as a visible light driven photocatalyst for the hydrogen generation from H2S. Electronic band structure with DOS has also been performed for both the materials. Being a stable single-phase ternary-layered oxide perovskites and band gap (2.75eV) in visible domain, they may have potential applications in electronic devices as well. [Copyright &y& Elsevier]

Abstract: Photocatalytic application of the thermal catalyst Fe2O3 in hydrogen production from H2S requires a chemical modification to lessen/avoid the chemical attack by H2S. Incorporating this objective, in the present work FeGaO3 with equimolar Fe and Ga contents was prepared by solid state (SS) and hydrothermal (HT) routes. The resulting materials, FeGaO3-SS and FeGaO3-HT are found to have characteristically different crystalline structures and morphology. Their photocatalytic activities in the unloaded/pristine and 1 wt% NiO x -loaded forms as well as in the fresh and used conditions in hydrogen production from H2S under visible light (λ ≥420nm) reveal that the synthesized photocatalysts are stable in their functionalities and the trends are quite interesting and unusual. The structure–activity investigation clearly suggests the key role of their material configurations in deciding photofunctionalities. The fair quantum yields (7–9% at 550nm), the regenerative and reusable features plus the scope for improvement through optimum Ga content, all make the new photocatalysts promising. [Copyright &y& Elsevier]

Abstract: Spinel metal oxide photocatalysts, a rarely studied group in visible light driven photocatalytic decomposition of and solar production, have been investigated in the present work. p-block element, Ga containing spinel in pristine and doped (, ) states, was prepared by ceramic route without/with noble metal oxide, loading to the extent of 1wt%. XRD analysis reveals a single-phase cubic spinel crystalline structure for all the catalysts. FESEM displays an irregular-shaped grain morphology for and smaller size almost cubic particles for . Energy dispersive X-ray spectroscopy suggests a chemical composition consistent with the stoichiometric molecular formula. Optically, the catalysts display an intensive light absorption in UV and visible regions with an onset at about 900nm in the near IR region. doping constructively influences the morphology and optical properties of pristine . All these physico-chemical and material characteristics infuse a facile catalytic function into the prepared spinel oxides such that the naked and spinels exhibit a moderate to fairly good photocatalytic activity while the co-catalyst-loaded spinel performs an exceedingly good photocatalytic activity with 15% quantum efficiency. Thus, the present work leads to the emergence of functionally high performance, stable and visible active photocatalysts in the spinel group for the production of solar hydrogen from . [Copyright &y& Elsevier]

Abstract: The present communication is the report of our research work on synthesis of new delafossite oxides containing Ga/Ga and In p-block elements, and their visible light driven catalytic activity in solar H2 production from H2S decomposition. CuGaO2 and its indium doped analogue CuGa1−x In x O2 (x =0.065) delafossite oxides without/with NiO and RuO2 co-catalysts loading in nanostructures were prepared by solid state reaction method. These materials possess hexagonal rhombohedral structure (XRD); morphologically CuGaO2 has irregularly-shaped plate like particles while all others have ordered hexagonal rod-like arrangements (FESEM). Co-catalyst deposits of few nm sizes are observable as white spots/patches on the surface of naked oxide catalysts. Acquiring p-type conductivity from the mixed valence of Cu (+1 and +2) and oxygen deficiency, these catalysts strongly absorb visible light (Eg=1.85eV) in a wide wavelength range. They decompose H2S in aqueous 0.5M KOH solution under visible light (λ ⩾420nm) irradiation and generate H2 to the tune of 4300μmol/h, giving rise to a high quantum efficiency of 13.6% at 550nm. The exceedingly higher rate of H2 production appears to result from a combined contribution of chemical nature (p-block elements Ga and In), p-type conductivity and an efficient e−–h+ separation. [Copyright &y& Elsevier]

Abstract: Rose-red color oxynitride photocatalyst was synthesized by thermal ammonolysis of at 1073K. TEM image of sample showed prismatic pseudo orthorhombic shaped particles with clear edges and an average particle size in the range of 80–90nm. The photocatalytic activities of the oxynitride samples were studied for hydrogen production by splitting under visible light irradiation. The oxynitride gave the quantum yield of 13.5% in the production of hydrogen from decomposition of hydrogen sulfide under visible light irradiation. [Copyright &y& Elsevier]

Abstract: We report here the synthesis of self-assembled aligned hexagonal prismatic Cu doped ZnO nanoparticles in aqueous and organic medium. The average particle size was found to be in the range of 40–85nm. Structural study revealed the existence of ZnO phase with wurtzite structure. The copper was present as oxide, situated at the core of prismatic form of wurtzite ZnO nanoparticle with clear edges and faces. The maximum hydrogen production rate achieved was 1932μmolh−1 over the as synthesized Cu doped ZnO suggesting as an active photocatalyst for hydrogen sulfide decomposition under visible light irradiation. The effect of copper concentration as a dopant on the photocatalytic activity of Cu-ZnO was studied. The photocatalytic activity of Cu-ZnO synthesized in organic media was observed to be higher as compared to aqueous medium. [Copyright &y& Elsevier]

Abstract: We have calculated electronic structure of InTaO4 using first-principle method, in order to investigate the relationship between its electronic structures and visible light absorption. We have calculated densities of states (DOS) for various states of InTaO4, such as pristine, oxygen vacancy, Ni-doped, and A-doped (A=C, N, and S) states. We have found that oxygen vacancy can induce the gap states and Ni-doping can narrow the band gap by generating additional states on the top of the valence band as well as on the top of the gap states. For A-doped states, it was found that N-doping and S-doping could narrow the pristine band gap inducing the additional states above the pristine valence band, while C-doping can generate the gap states in the middle of the pristine band gap. To cite this article: H. Chang et al., C. R. Chimie 9 (2006) . [Copyright &y& Elsevier]

Abstract: Enantioselective esterification of racemic ibuprofen catalyzed by Candida rugosa lipase in isooctane was coupled with pervaporation of water by-produced by the reaction. A cross-linked poly(vinyl alcohol) (PVA) membrane and commercially available perfluorinated membranes (Nafion® 117 and Nafion® NE 450) were tested for selective removal of water from the reaction mixture. Effects of the reaction temperature, the concentration and nature of alcohol on the reaction rate and enantioselectivity were investigated systematically with and without pervaporation. The PVA pervaporation membrane appeared to be more suitable for the enantioselective esterification of ibuprofen than the Nafion® membranes. The highest initial rate and enantiomeric ratio were obtained at an equimolar ratio of 1-octanol/1-decanol to racemic ibuprofen regardless of the application of pervaporation. Raising the reaction temperature from 30 to 60°C increased the reaction rate, but decreased the enantiomeric ratio. However, in most cases, the concomitant pervaporation operation brought about the enhancement of the reaction rate and the enantiomeric ratio. This was thought to be due to the selective removal of excess water by pervaporation, leading to the reduction of undesirable effects on the enzymatic reaction by the excess water. [Copyright &y& Elsevier]

Abstract: Lipase from Candida rugosa was entrapped by drop-wise addition of an aqueous mixture of sodium alginate and the biocatalyst to a hardening solution of a Ca2+ salt. Effects of immobilization conditions such as alginate concentration, CaCl2 concentration, ratio by weight of enzyme to alginate (E/A) and bead size on loading efficiency (percent of total enzyme entrapped) and immobilization yield (specific activity ratio of entrapped lipase to free lipase) were investigated. An increase in alginate concentration raised loading efficiency, but decreased immobilization yield. CaCl2 concentration was expected to have a similar effect on loading efficiency and immobilization yield, but the effect was small in the tested range of 50–300mM. With increasing bead size, immobilization yield decreased due to mass transfer resistance, but loading efficiency was unchanged. In order to prevent enzyme from leaking out of the gel beads, beads were coated with chitosan and silicate. Compared to non-coated beads, coated alginate beads showed the higher re-usability, illustrating the effectiveness of the coating method. When coated with silicate, lipase-entrapped beads retained the highest catalytic activity. [Copyright &y& Elsevier]

Abstract: We have carried out the first-principle electronic structure calculations based on density functional theory on InTaO4 in various states, such as pristine, oxygen vacancy, and Ni-doped states. We have found that oxygen vacancy can induce the gap states and Ni-doping can narrow the band gap by generating additional states on the top of the valence band as well as on the top of the gap states. From our calculated results, we have shown that oxygen vacancy can do a crucial role to generate gap states which let InTaO4 absorb the visible light. [Copyright &y& Elsevier]

2,2-bis(3,4-Dicarboxyphenyl) hexafluoropropane dianhydride (6FDA)–based polyimides with a polar group of hydroxyl or carboxyl such as 6FDA–BAPAF, 6FDA–DAP, and 6FDA–DABA were synthesized by the thermal imidization method. The corresponding composite membranes were then prepared by the dip-coating technique using a poly (ether sulfone) (PES) membrane as a supporting layer. Some alcohols and glycol ethers were used as coating solvents during the membrane preparation. The solubility of the polyimides synthesized in this study in these solvents depended on the nature of polymers and solvents. CO2 permeances for these composite membranes were measured in comparison with those for other gases such as H2, O2, N2, and CH4. The membrane performances were affected considerably by the preparation conditions such as the kinds of diamine moiety, coating solvent, and coating polymer concentration. It was expected that these composite membranes could be applied usefully to the CO2 separation, considering the CO2 permeances in the range of 20–38 gas permeation unit (GPU) and the selectivities for CO2/N2 and CO2/CH4 equal to or even higher than those of other dense or asymmetric membranes of 6FDA-based polyimides reported in the literature. [Copyright &y& Elsevier]

The room temperature (RT) processability of the photoactive layers in polymer solar cells (PSCs) from halogen‐free solvent along with their highly reproducible power conversion efficiencies (PCEs) and intrinsic thickness tolerance are extremely desirable for the large‐area roll‐to‐roll (R2R) production. However, most of the photoactive materials in PSCs require elevated processing temperatures due to their strong aggregation, which are unfavorable for the industrial R2R manufacturing of PSCs. These limiting factors for the commercialization of PSCs are alleviated by synthesizing random terpolymers with components of (2‐decyltetradecyl)thiophen‐2‐yl)naphtho[1,2‐c:5,6‐c′]bis[1,2,5]thiadiazole and bithiophene substituted with methyl thiophene‐3‐carboxylate (MTC). In contrast to the temperature‐dependent PNTz4T polymer, the resulting random terpolymers (PNTz4T‐MTC) show better solubility, slightly reduced crystallinity and aggregation, and weaker intermolecular interaction, thus enabling PNTz4T‐MTC to be processed at RT from a halogen‐free solvent. Particularly, the PNTz4T‐5MTC‐based photoactive layer exhibits an excellent PCE of 9.66%, which is among the highest reported PCEs for RT and ecofriendly halogen‐free solvent processed fullerene‐based PSCs, and a thickness tolerance with a PCE exceeding 8% from 100 to 520 nm. Finally, large‐area modules fabricated with the PNTz4T and PNTz4T‐5MTC polymer have shown 4.29% and 6.61% PCE respectively, with an area as high as 54.45 cm2 in air. [ABSTRACT FROM AUTHOR]

Abstract: The P3HT:PCBM bulk heterojunction solar cell fabricated by doctor blade was investigated. Interestingly, the bladed solar cell showed higher the open-circuit voltage (Voc), the short-circuit current (Jsc), fill factor, and power conversion efficiency (PCE) than spin-coated solar cell, and it is also observed that the phases of P3HT and PCBM is separated well. The bladed cell shows high UV–Vis absorption and external quantum efficiency, therefore it is estimated that the dense film might be coated for some reason. The PCE of the optimized solar device was 3.6%. [Copyright &y& Elsevier]

Abstract: We prepared the inverted polymer solar cells (PSCs) with a fluorine-doped tin oxide (FTO) as a transparent electrode and with TiO2, WO3 and WO x as selective charge transport layers. An adequately thick TiO2 nanoparticles layer was employed for covering a very rough FTO surface. Using a solution-based WO x film instead of a vacuum deposited WO3 layer in inverted polymer solar cells showed comparable device performance. A self-assembled molecular (SAM) layer of PCBA and N719 on top of TiO2 improves the device performance by reducing the series resistance at the interface between the active layer and the TiO2 film. The power conversion efficiency (PCE) was improved by 16%, especially in the case of [6,6]-phenyl-C61-butyric acid (PCBA). [Copyright &y& Elsevier]

This study aimed to quantify the predictability of arch expansion in children with early mixed dentition treated with the Invisalign First® system and evaluate the clinical factors for the predictability of arch expansion. Pretreatment, predicted and posttreatment digital models from Invisalign's ClinCheck® software were obtained for 90 children with mean (standard deviation) age of 8.42 (0.93) who planned arch expansion. Arch width measurements were collected using Invisalign's arch width table. The predictability of expansion was calculated by comparing the amount of expansion achieved with the predicted expansion. Linear regression analysis was used to evaluate clinical factors associated with predictability of expansion. The predictability of the expansion of the maxillary teeth was as follows: 71.1% primary canines (n = 55), 67.5% first primary molars (n = 46), 65.2% second primary molars (n = 79), and 53.4% first permanent molars (n = 90); the predictability of the expansion of the mandibular teeth was 81.1% primary canines (n = 31), 81.2% first primary molars (n = 51), 77.8% second primary molars (n = 80), and 69.4% first permanent molars (n = 90). The predictability of arch expansion was significantly higher in the mandibular arch compared to the maxillary arch and significantly lower in the permanent first molar than in the other primary teeth. Predictability decreased significantly as the amount of predicted expansion per aligner increased in the upper and lower permanent first molars, primary second molars, and upper primary canines. Predictability significantly increased when buccal or palatal attachments were placed on the bilateral side compared to cases without attachment at the upper permanent first and primary second molars. The predictability of arch expansion using the Invisalign First® system varies according to arch and tooth type. The amount of predicted expansion per aligner and the number of attachments to the maxillary teeth are potential clinical factors that can affect the predictability of expansion., Competing Interests: The authors declare no conflict of interest., (©2024 The Author(s). Published by MRE Press.)

The data provided in this data set is the study of organic-inorganic hybrid perovskite solar cells fabricated through incorporating the small amounts of ammonium halide NH 4 X (X = F, Cl, Br, I) additives into a CH 3 NH 3 PbI 3 (MAPbI 3 ) perovskite solution and is published as "High-Performance CH 3 NH 3 PbI 3 Inverted Planar Perovskite Solar Cells via Ammonium Halide Additives", available in Journal of Industrial and Engineering Chemistry [1]. A compact and uniform perovskite absorber layer with large perovskite crystalline grains, is realized by simply incorporating small amounts of additives into precursor solutions, and utilizing the anti-solvent engineering technique to control the nucleation and growth of perovskite crystal, turning out the enhanced device efficiency (NH 4 F: 14.88 ± 0.33%, NH 4 Cl: 16.63 ± 0.21%, NH 4 Br: 16.64 ± 0.35%, and NH 4 I: 17.28 ± 0.15%) compared to that of a reference MAPbI 3 device (Ref.: 12.95 ± 0.48%). In addition, this simple technique of ammonium halide addition to precursor solutions increase the device reproducibility as well as long term stability., (© 2019 The Authors.)

Most non-fullerene acceptors (NFAs) are designed in a complex planar molecular conformation containing fused aromatic rings in high-efficiency organic solar cells (OSCs). To obtain the final molecules, however, numerous synthetic steps are necessary. In this work, a novel simple-structured NFA containing alkoxy-substituted benzothiadiazole and a rhodanine end group (BTDT2R) is designed and synthesized. We also investigate the photovoltaic properties of BTDT2R-based OSCs employing representative polymer donors (wide band gap and high-crystalline P3HT, medium band gap and semicrystalline PPDT2FBT, and narrow band gap and low-crystalline PTB7-Th) to compare the performance capabilities of fullerene acceptor-based OSCs, which are well matched with various polymer donors. OSCs based on P3HT:BTDT2R, PPDT2FBT:BTDT2R, and PTB7-Th:BTDT2R achieved efficiency as high as 5.09, 6.90, and 8.19%, respectively. Importantly, photoactive films incorporating different forms of optical and molecular ordering characteristics exhibit favorable morphologies by means of solvent vapor annealing. This work suggests that the new n-type organic semiconductor developed here is highly promising as a universal NFA that can be paired with various polymer donors with different optical and crystalline properties.

A non-fullerene small molecule acceptor, SF-HR composed of 3D-shaped spirobifluorene and hexyl rhodanine, was synthesized for use in bulk heterojunction organic solar cells (OSCs). It possesses harmonious molecular aggregation between the donor and acceptor, due to the interesting diagonal molecular shape of SF-HR. Furthermore, the energy level of SF-HR matches well with that of the donor polymer, poly(3-hexyl thiophene) (P3HT) in this system which can affect efficient charge transfer and transport properties. As a result, OSCs made from a P3HT:SF-HR photoactive layer exhibited a power conversion efficiency rate of 4.01% with a high V OC of 1.00 V, a J SC value of 8.23 mA cm -2 , and a FF value of 49%. Moreover, the P3HT:SF-HR film showed superior thermal and photo-stability to P3HT:PC 71 BM. These results indicate that SF-HR is specialized as a non-fullerene acceptor for use in high-performance OSCs., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

Solution-processed organic solar cells (OSCs) and hybrid perovskite solar cells (PvSCs) generally require appropriate transparent electrode with a low work function, which improves the electron extraction, increases the built-in potential, and suppresses charge recombinations. Hence, interfacial modifiers between the cathode and the photoactive layer play a significant role in OSCs and PvSCs, as they provide suitable energy-level alignment, leading to desirable charge carrier selectivity and suppressing charge carrier recombinations at the interfaces. Here, we present a comprehensive study of the energy-level mapping between a transparent electrode and photoactive layers to enhance the electron-transport ability by introducing amine-based interfacial modifiers (ABIMs). Among the ABIMs, polyethylenimine ethoxylated (PEIE) incorporating inverted OSCs shows enhanced power conversion efficiencies (PCEs) from 0.32 to 9.83% due to large interfacial dipole moments, leading to a well-aligned energy level between the cathode and the photoactive layer. Furthermore, we explore the versatility of the PEIE ABIM by employing different photoactive layers with fullerene derivatives, a nonfullerene acceptor, and a perovskite layer. Promisingly, inverted nonfullerene OSCs and planar n-i-p PvSCs with PEIE ABIM show outstanding PCEs of 11.88 and 17.15%, respectively.

The reduction of charge carrier recombination and intrinsic defect density in organic-inorganic halide perovskite absorber materials is a prerequisite to achieving high-performance perovskite solar cells with good efficiency and stability. Here, we fabricated inverted planar perovskite solar cells by incorporation of a small amount of excess organic/inorganic halide (methylammonium iodide (CH 3 NH 3 I; MAI), formamidinium iodide (CH(NH 2 ) 2 I; FAI), and cesium iodide (CsI)) in CH 3 NH 3 PbI 3 perovskite film. Larger crystalline grains and enhanced crystallinity in CH 3 NH 3 PbI 3 perovskite films with excess organic/inorganic halide reduce the charge carrier recombination and defect density, leading to enhanced device efficiency (MAI+: 14.49 ± 0.30%, FAI+: 16.22 ± 0.38% and CsI+: 17.52 ± 0.56%) compared to the efficiency of a control MAPbI 3 device (MAI: 12.63 ± 0.64%) and device stability. Especially, the incorporation of a small amount of excess CsI in MAPbI 3 perovskite film leads to a highly reproducible fill factor of over 83%, increased open-circuit voltage (from 0.946 to 1.042 V), and short-circuit current density (from 18.43 to 20.89 mA/cm 2 ).

Aiming at improving the phase behavior of the OPVCs, we have designed and synthesized a series of C60 and C70 derivatives, which showed high electron mobility, electron affinity, and good solubility. These methanofullerene acceptor materials having ethyleneoxy substituent, PCBEs, were synthesized from the reaction of fullerene C60 or C70 with each hydrizide. Device performances of OPVC using the mixture of P3HT and PCBEs as an active layer were measured under illumination of 100 mW/cm2 AM 1.5G simulated light. Pristine OPVC using P3HT:compound 3 showed 2.59% of power conversion efficiency, which is much higher than 1.65% of pristine P3HT:PCBM device. The electrochemical and photophysical properties of these methanofullerene derivatives were examined by using cyclicvoltammetry and UV-Vis spectroscopy, respectively. We revealed that ethyleneoxy substituted methanofullerenes can be used as a good candidate for acceptor materials in OPVCs.

We report studies of the effect of hydrothermal treatment on physical properties such as crystalline phase, size, and morphology of nanosized cadmium sulfide (CdS) particles. CdS precipitates have been synthesized by the reaction of Cd(NO(3))(2) with Na(2)S at room temperature. These CdS precipitates have been hydrothermally treated in the range 120-240 degrees C with variation of the treatment time. The effects of acid catalysts and other additives were also investigated. The particles prepared were characterized by XRD, TEM, and BET methods. With increased hydrothermal treatment temperature and time, crystallization from amorphous to crystalline form, cubic or hexagonal, and an increase of particle size occurred. CdS particles of well-developed hexagonal form were obtained at a hydrothermal treatment temperature of 240 degrees C; the primary hexagonal grain size was on the order of 20-30 nm. The addition of an acid catalyst, HCl, or of Cd(NO(3))(2) into the precipitate sol promoted crystal growth and phase transformation during the hydrothermal treatment, but another additive, Na(2)S, showed the opposite trend. It appears that hydrothermal treatment combined with proper additives could be an effective method for preparation of nanosize crystalline CdS particles. Copyright 2001 Academic Press.