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A new wide bandgap (WBG) conjugated polymer diO-PBDB-T containing alkoxy substituted thiophene spacer was designed and synthesized for application as a donor in nonfullerene acceptor (NFA) based po...

A–D–A′–D–A-type nonfused-ring acceptors (NFRAs) have recently received extensive attention because of their suitable tuning of absorption spectra, frontier energy levels, and promising sunlight har...

Solution processability is one of the advantages of organic solar cells (OSCs). However, most high-efficiency OSCs are prepared using hazardous chlorinated solvents for the deposition of photoactive layers. The replacement of non-halogenated solvents with eco-friendly green solvents for photoactive materials is urgently required. Herein, we have developed a novel asymmetric T2-OEHRH, which is modified from the symmetric T2-ORH. The introduction of asymmetric alkyl side chains onto rhodanine end groups can effectively suppress excessive self-aggregation/crystallization and substantially improve solubility without sacrificing optoelectrical properties. Therefore, ternary-blend OSCs based on PTB7-Th:EH-IDTBR:T2-OEHRH processed using a non-halogenated solvent system exhibit a uniform and favorable morphology and give a high power conversion efficiency (PCE) of 12.10%. More importantly, we demonstrate an impressive PCE of 9.32% for large-area NFA-OSCs (substrate size = 100 cm2 and aperture size = 55.5 cm2) prepared via D-bar coating in air. To our knowledge, this PCE is the highest reported to date for NFA-based large-area OSC modules processed from a non-halogenated solvent. This asymmetric alkyl-chain engineering strategy can be exploited to develop high-performance large-area NFA-OSCs with eco-friendly solvent processing.

A simple-structured nonfullerene acceptor (NFA), T2-ORH, consisting of a bithiophene core and octyl-substituted rhodanine ends is utilized as the third component in ternary-blend solar cells with PTB7-Th and EH-IDTBr as host materials. T2-ORH is a wide band gap NFA and specially contributes to light absorption, which provides complimentary absorption with a low band gap acceptor, EH-IDTBR. In the ternary device, a PCE of 11.55%, a short circuit current (JSC) of 17.51 mA cm−2, a fill factor (FF) of 63% and an open circuit voltage (VOC) of 1.05 V were achieved with a 1 : 1 : 1 blend ratio. In this ternary system, it is estimated that the two NFAs work as one alloy-like acceptor and energy transfer model from T2-ORH to EH-IDTBR for efficient ternary-blend organic solar cells (OSCs). On conducting thermal, light, and air-process stability tests, the ternary-blend systems show superior stability performance owing to the formation of a stable and robust morphology. Finally, we fabricated a large-scale device (5 cm × 5 cm substrate, 13.5 cm2 aperture size, and a geometric FF of 54%) with the same ternary system. The sub-module ternary-blend OSCs displayed the highest PCE of 10.08% with JSC = 2.83 mA cm−2, VOC = 6.36 V and FF = 56%. As a result, ternary-blend OSCs show tremendous promise for use in actual applications.

A novel series of benzodithiophene-4,8-dione (BDD)-based copolymers, poly[(4,4,9,9-tetrakis(4-hexylphenyl)-4,9-dihydro-s-indacenodithiophene-2,7-diyl)-alt-(1,3-bis(2-ethylhexyl)-5,7-di(thiophene2-yl)benzodithiophene-4,8-dione)] (P1) and poly[(5,5,11,11-tetrakis(4-hexylphenyl)dithieno[2,3-d: 2',3'-d']-s-indacenodithiophene-3,9-diyl)-alt-(1,3-bis(2-ethylhexyl)-5,7-di(thiophene-2-yl)benzodithiophene-4,8-dione)] (P2), which have the same acceptor moiety but different donor segments, have been designed and synthesized for use as donor materials in solution-processable polymer solar cells (PSCs). The optical and photovoltaic properties of the copolymers were investigated. The band gaps of the copolymers were in the range 1.91-1.92 eV. Under optimized conditions, the BDD-based polymers showed power conversion efficiencies (PCEs) for the PSCs in the range 2.52-2.92% under AM 1.5 illumination (100 mW/cm2). Among the copolymers, P1, which contained an indacenodithiophene donor unit, showed a power conversion efficiency of 2.92% with a short circuit current of 7.30 mA/cm2, open circuit voltage of 0.92 V, and a fill factor of 0.43, under AM 1.5 illumination (100 mW/cm2).

BACKGROUND Postoperative nausea and vomiting (PONV) is one of the major concerns after anesthesia and surgery, and it may be more frequent in orthopedic patients receiving patient-controlled epidural analgesia (PCEA). The purpose of this study was to compare the effect of palonosetron and dexamethasone on the prevention of PONV in patients undergoing total joint arthroplasty and receiving PCEA. METHODS Patients scheduled for total hip or knee arthroplasty under spinal anesthesia/PCEA were randomly allocated to receive either intravenous palonosetron (0.075 mg, n = 50) or dexamethasone (5 mg, n = 50). Treatments were administered intravenously to the patients 30 min before the beginning of surgery. The total incidence of PONV and incidence in each time period, severity of nausea, need for rescue anti-emetics, pain score, and adverse effects during the first 48 h postoperatively were evaluated. RESULTS The total incidence of PONV was lower in the palonosetron group compared with the dexamethasone group (18.4% vs. 36.7%, P = 0.042), but there were no statistically significant differences in incidence between the groups at all time points. No significant intergroup differences were observed in the severity of nausea, use of rescue anti-emetics, pain score, and adverse effects. CONCLUSIONS Although there were no significant differences in the incidence of PONV between the treatment groups at all time points, intravenous palonosetron reduced the total incidence of PONV in orthopedic patients receiving PCEA compared with dexamethasone.

A newly synthesized small molecule donor, BDTT-2DPPBFu, is designed for incorporation into the photo-active layer in solution-processed small molecule organic photovoltaics (SM-OPVs). The effects of a solvent additive (1-chloronaphthalene, CN) on the bulk heterojunction morphology of a BDTT-2DPPBFu donor:fullerene derivative acceptor (PC71BM) are investigated and correlated with the device performance. A TEM analysis revealed that the nanomorphology of the SM-OPVs evolved dramatically with increasing solvent additive volume. With an optimum concentration of 2.5 vol% CN, a nanomorphology with a fibrillar and interpenetrating network on the order of exciton diffusion length (∼10–15 nm) is formed, resulting in improvement of the short-circuit current density, fill factor, and power conversion efficiency. Further GIWAXS studies have shown that the π–π stacking distance of BDTT-2DPPBFu small molecules is reduced and the inter-mixing of PC71BM within the BDTT-2DPPBFu-rich phase in the photo-active layer processed from 2.5 vol% CN is increased, leading to enhanced charge transport and reduced charge recombination and transfer resistance. The present work provides important progress in the nanomorphology of the photo-active layer, which can be effectively tuned via the use of a solvent additive in SM-OPVs.

We performed systematic experiments based on a small molecule donor and a polymer acceptor containing a naphthalene diimide (NDI)-based polymer as compared with fullerene-based acceptor (PC71BM) solar cells. Among polymer acceptors, the NDI-based polymer (PNDI-2T) shows good properties such as broad light absorbance with a strong absorption co-efficient and a well oriented crystalline structure leading to high electron mobility. We monitored the photovoltaic properties of both PNDI-2T and PC71BM acceptors with a BDT2TR donor. Although the BDT2TR:PC71BM device showed a higher PCE of 8.20%, the BDT2TR:PNDI-2T device also showed remarkable photovoltaic results with a PCE of 4.43%, VOC of 0.86 V, JSC of 7.26 mA cm−2, and FF of 71% indicating one of the highest efficiencies for small molecule donor and non-fullerene polymer acceptor systems. In particular, the PNDI-2T acceptor showed excellent thermal stability and intrinsic mechanical performance as compared with the PC71BM acceptor. To demonstrate the potential of the polymer acceptor for solar devices, we fabricated a device for testing thermal stability, high thickness tolerance, and the flexibility of the solar cell with bending stress. As a result, the PNDI-2T-based solar cell exhibited excellent thermal stability at 150 °C for 15 h and the PCE of the BDT2TR:PNDI-2T device with a thick active layer (around 610 nm) maintained 80% of its initial value. Moreover, the flexible device with the BDT2TR:PNDI-2T system retained its homogeneous morphology and showed maintained photovoltaic performance even after 100 bending cycles. Therefore, PNDI-2T based organic solar cells have good potential for application as flexible and portable real energy generators.

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 VOC of 1.00 V, a JSC 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:PC71BM. These results indicate that SF-HR is specialized as a non-fullerene acceptor for use in high-performance OSCs.

We studied fullerene-free organic solar cells based on electron-donating (BDT3TR) and -accepting (O-IDTBR) small molecules. Bulk heterojunction devices comprising BDT3TR:O-IDTBR showed an excellent power conversion efficiency exceeding 7% and much better thermal stability than BDT3TR:PC70BM devices after ageing at 120 °C for 300 hours.

The molecular self-organization of organic semiconductors, which is mainly determined by the structural design, film processing, and device configuration, is one of the crucial factors for achieving high-performance organic photovoltaics (OPVs) and perovskite solar cells (PvSCs). In this study, we newly synthesized and developed strongly self-organized small molecules via alkyl side-chain engineering. Replacing “H” to “C6H13” on the thienyl group, SM2 showed a well-ordered face-on orientation. Due to favorable self-organization leading to effective charge carrier dynamics, including enhanced charge transfer/transport and suppressed recombination, SM2-based OPVs and PvSCs exhibited improved device performance compared to the devices based on SM1 without an additional hexyl side-chain. The best fullerene-based OPV and planar PvSC with SM2 as a small-molecule donor and as a hole transport layer (HTL) achieved an unprecedentedly high efficiency of 9.38% and 20.56%, in contrast with SM1-based devices showing lower efficiency of 8.70% and 15.37%. Furthermore, the planar PvSCs based on undoped-SM2 HTL exhibited comparable efficiency but provided excellent heat and humidity stability compared with doped spiro-OMeTAD-based devices. These results clearly indicated that SM2 with highly-ordered and favorable self-organization is a promising organic semiconductor for future applications of high-performance organic and inorganic-organic hybrid electronics.

Two benzo[1,2-b:4,5-b’]dithiophene (BDT)-based copolymers, poly[4,8-bis(5-(2-ethylhexyl) thiophene-2-yl)benzo[1,2-b:4,5-b’]dithiophene-alt-5,8-(2,3-bis(4-octyloxy)phenyl)quinoxaline] (P1) and poly[4,8-bis(5-(2-ethylhexyl)thiophene-2-yl)benzo[1,2-b:4,5-b’]dithiophene-alt-5,7-(2,3-bis(4- octyloxy)phenyl)thieno[3,4-b]pyrazine] (P2), are synthesized and used as donor materials in polymer solar cells (PSCs). To obtain a low band gap polymer, we use a copolymerized donor-acceptor structure. The optical, electrochemical, and photovoltaic properties of the copolymers are investigated. The results indicate that the acceptor units in the copolymers influenced the band gap, electronic energy levels, and photovoltaic properties of the copolymers significantly. The band gaps of the copolymers are in the range 1.34 − 1.75 eV. Under optimized conditions, the BDT-based polymers showed power conversion efficiencies (PCEs) for the PSCs in the range 1.46 − 2.05% under AM 1.5 illumination (100 mW/cm2).

A series of four donor-acceptor alternating copolymers based on dialkyloxy-benzothiadiazole (ROBT) as an acceptor and thienoacenes as donor units were synthesized and tested for polymer solar cells (PSCs). These new polymers had different donor units with varied electron-donating ability (thieno[3,2-b]thiophene (TT), dithieno[3,2-b:2',3'-d]thiophene (DTT), benzo[1,2-b:4,5-b']dithiophene (BDT), and naphtha[1,2-b:5,6-b']dithiophene (NDT)) in the polymer backbone. To understand the effect of these thienoacenes on the optoelectronic and photovoltaic properties of the copolymers, we systematically analyzed and compared the energy levels, crystallinity, morphology, charge recombination, and charge carrier mobility in the resulting polymers. In this series, optimized photovoltaic cells yielded power conversion efficiency (PCE) values of 6.25% (TT), 9.02% (DTT), 6.34% (BDT), and 2.29% (NDT) with different thienoacene donors. The introduction of DTT into the thienoacene-ROBT polymer enabled the generation of well-ordered molecular packings with a π-π stacking distance of 3.72 Å, high charge mobilities, and an interconnected nanofibrillar morphology in blend films. As a result, the PSC employing the polymer with DTT exhibited the highest PCE of 9.02%. Thus, our structure-property relationship studies of thienoacene-ROBT-based polymers emphasize that the molecular design of the polymers must be carefully optimized to develop high efficient PSCs. These findings will help us to understand the impact of the donor thienoacene on the optoelectronic and photovoltaic performance of polymers.

Background: Coccygodynia is a pain in the region of the coccyx that radiates to the sacral, perineal area. The cause of the pain is often unknown. Coccygodynia is diagnosed through the patient's past history, a physical examination, and dynamic radiographic study, but the injection of local anesthetics or a diagnostic nerve blockade are needed to distinguish between somatic, neuropathic, and combined pain. Ganglion impar is a single retroperitoneal structure made of both paravertebral sympathetic ganglions. Although there are no standard guidelines for the treatment of coccygodynia, ganglion impar blockade is one of the effective options for treatment. Methods: Here, we report a 42-year-old female patient presenting with severe pain in the coccygeal area after spinal arachnoid cyst removal. Results: Treatment involved neurolysis with absolute alcohol on the ganglion impar through the transsacrococcygeal junction. Pain was relieved without any complications. Conclusion: Our case report offers the ganglion impar blockade using the transsacrococcygeal approach with absolute alcohol can improve intractable coccydynia.

Hyperlipidemia and marrow fat are associated with lowering bone density in vivo, suggesting that lipid contributes to bone loss. Using bone marrow-derived macrophages, we investigated the effect of saturated fatty acids (SFA) on osteoclastogenesis. The level of free fatty acids and adiposity in bone marrow was significantly elevated in obese mice. SFA increased osteoclast (OC) survival by preventing apoptosis. SFA caused the production of MIP-1alpha and led to activation of nuclear factor (NF)-kappaB in the OC. The absence of Toll-like receptor 4 (TLR4) or myeloid differentiation factor 88 (MyD88) abolished the survival effect of SFA on OC.

Ovariectomy (OVX)-induced estrogen withdrawal resulted in both bone loss and an increase in fat. We observed elevated osteoclast (OC) formation by bone marrow-derived macrophages treated with medium conditioned by fats from OVX mice, but not from sham-operated mice. Fats from OVX mice expressed and secreted higher levels of monocyte chemoattractant protein-1 (MCP-1) than those from sham-operated mice. Increased fat resulting from estrogen deficiency is thus responsible for bone loss due to enhanced OC formation, which is, at least partly, a consequence of elevated MCP-1 production.

The chemical states of the HfO2/Si (100) interface were investigated using transmission electron microscopy and high-resolution x-ray photoelectron spectroscopy. The depth distributions of Hf chemical states showed that the Hf 4f binding energy remains unchanged with the depth and there is no signature of more than one Hf-O state. These facts strongly suggest that the chemical state of the interfacial layer is not Hf-silicate, as previously believed. Instead, the compositions are mainly Si2O3 and SiO2, judging from the deconvolution of Si 2p spectra. The dielectric constant κ=4.8 of the interfacial layer is also consistent with the above conclusions.

Solution-processed organic solar cells are promising owing to their light weight, ease of processability, low cost, flexibility, and large-area fabrication. Particularly, small-molecule active materials have been recently developed using straightforward synthesizing methods, exhibiting the least batch-to-batch variation in physical and optoelectronic properties and highly reproducible efficiency. A series of 2D-BDT-based active materials with various numbers of benzodithiophene (BDT) units and how the number of 2D-BDT units influences the construction of a well-defined interconnected structure are reported. The systematically controlled morphology of the 2D-BDT material helps achieve a high power-conversion efficiency (PCE) of 8.56% and a high fill factor of 0.73 without the use of additives. The reduced charge recombination and well-constructed morphology of this material facilitate a PCE of 7.45% in a 77.8 cm2 rigid module, which is the outstanding performance in large-area modules.

We have investigated the electronic structure of transition-metal (TM=Sc, Y, Zr, and Nb)-doped Al2O3 by x-ray photoemission spectroscopy (XPS) and x-ray absorption spectroscopy (XAS). In valence bands of these TM-doped Al2O3 measured by XPS, the highest occupied levels and the shapes of valence bands are almost unchanged from the pure alumina. On the other hand, XAS spectra obtained at the oxygen K-edge show that Nb- and Zr-doped Al2O3 show localized d states in the bandgap below the conduction band minimum, while Y- and Sc-doped Al2O3 have d states inside the conduction band of the original Al2O3. This implies that Y- and Sc-doped Al2O3 will show little bandgap degradation and maintain the same band offset as silica at the Si interface, and can serve as promising candidates for an alternative gate oxide.

Curcumin (diferuloylmethane), a pigment derived from turmeric, has anti-oxidant and anti-inflammatory activities. Accumulating evidence points to a biochemical link between increased oxidative stress and reduced bone density. Osteoclast formation was evaluated in co-cultures of bone marrow stromal cells (BMSC) and whole bone marrow cells (BMC). Expression of receptor activator of nuclear factor-kappaB ligand (RANKL) was analyzed at the mRNA and protein levels. Exposure to curcumin led to dose-dependent suppression of osteoclastogenesis in the coculture system, and to reduced expression of RANKL in IL-1alpha-stimulated BMSCs. Addition of RANKL abolished the inhibition of osteoclastogenesis by curcumin, whereas the addition of prostaglandin E2(PGE2) did not. The decreased osteoclastogenesis induced by curcumin may reduce bone loss and be of potential benefit in preventing and/or attenuating osteoporosis.

We present the commissioning results of a micro‐spot high‐resolution VUV & soft x‐ray photoemission beamline with a spherical grating monochromator at PAL. A negative‐order NOGARD‐type monochromator shows a good energy resolution enough for high‐resolution angle‐resolved photoemission spectroscopy, which is demonstrated by experimental photoabsorption spectra of various gases. The beam‐spot size at a sample position is estimated to be smaller than 10 × 10 μm2 (FWHM).