Search

e15561 Background: Immunotherapy has improved outcomes for metastatic colorectal cancer(mCRC) patients with MSI-H/dMMR but has not been effective in MSS/pMMR tumors, which comprise 95% of mCRC. In metastatic cancers, radiotherapy can be used as a local therapy and a sensitizer to PD-1/PD-L1 inhibitors. The synergistic effects of radiotherapy and PD-1/PD-L1 inhibitors can be reinforced by adding cytokines like granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-2(IL-2). Our previous PRaG trial demonstrated that PD-1 inhibitors in combination with radiotherapy and GM-CSF could improve clinical response in patients with advanced refractory solid tumors. We found that mCRC patients with MSS/pMMR could also benefit from the PRaG regimen. Methods: Patients of mCRC with MSS/pMMR were collected from the PRaG trial and PRaG 2.0 trial. A treatment cycle consisted of radiotherapy (5 or 8Gy×2-3f) delivered for one metastatic lesion, PD-1 inhibitor dosing within one week after completion of radiotherapy, GM-CSF 200μg subcutaneous (SC) injection once daily for 14 days(d1-14), or GM-CSF 200μg (d1-7), and then sequentially followed by IL-2 200 million IU SC once daily for 7 days(d8-14). PRaG regimen was repeated every 21 days for at least 2 cycles until no appropriate lesions for irradiation or reached the tolerance dose. Pooled analysis of response rate (ORR), median progression-free survival (PFS), and treatment-related adverse eventswere calculated. Results: With the cutoff date of 31 December 2021, a total of 9 mCRC patients with MSS/pMMR were enrolled. All of the patients completed at least 2 cycles of PRaG therapy and one evaluation. The median follow-up was 7.6 months (95%CI, 3.8, 11.4). The ORR was 22.2%, and the disease control rate(DCR) was 66.7%. The median PFS was 5.6 months (95%CI, 1.5 to 9.7). One patient got complete remission, with PFS over 17months. Treatment-related adverse events (TRAE) occurred in 7 of 9 (77.8%) patients. One patient (11.1%) occurred Grade3 TRAE of renal insufficiency. Conclusions: Our preliminary results suggest that the PRaG regimen could improve clinical outcomes in mCRC patients with MSS/pMMR with acceptable toxicity.

Background: Assemble Flavone of Rhizoma Drynariae (AFRD) is not only the extract of Rhizoma Drynariae, but also the effective component of Qianggu capsule, which is widely used in the treatment of fracture, bone defect, osteoporosis and other orthopedic diseases, and has achieved good results. Purpose of this trial was to explore effects of AFRD on bone graft mineralization and osteoblast differentiation in Masquelet induced membrane in rats.Methods: Twenty male Sprague-Dawley rats aged 10-12 weeks were randomLy divided into AFRD group (n=10) and control group (n=10). Critical-sized defects model of rats was established with 10 rats in each group. Polymethyl methacrylate (PMMA) was implanted into the defect of femur in rats. After the formation of the induced membrane, autogenous bone was implanted into the induced membrane. After 10 weeks of bone grafting, bone tissue in the bone graft area was examined by X-ray, Micro-CT and hematoxylin-eosin (HE) staining to evaluate the growth of the bone graft. Serums of the two groups of rats were extracted respectively, and these serums were used to culture osteoblasts in vitro. CKK8 method, Alkaline phosphatase (ALP) staining, Western blot and RT-PCR and other methods were used to evaluate the effects of AFRD on the proliferation of osteoblasts and the regulation of Wnt/β-catenin signal pathway.Results: In vivo experiment showed that the growth and mineralization effect of bone graft in AFRD group was better. In vitro experiment showed that osteoblasts proliferated faster, ALP activity was higher, number of mineralized nodules was more, and expression of proteins related to Wnt/β-catenin signal pathway and osteogenesis were more in AFRD group.Conclusions: AFRD can promote mineralization of bone graft and differentiation of osteoblasts during the bone graft growth period of induced membrane technique, which is related to the activation of Wnt/ β-catenin signal pathway.

A density functional theory based semiempirical van der Waals (vdW) method with dielectric functions being incorporated is developed for two-dimensional materials. The coefficients of interatomic pairwise potentials are derived from atomic polarizabilities obtained via a Clausius-Mossotti relation dedicated for layered crystals. The method not only can efficiently describe the dispersion energy for a range of planar graphene-like materials at nearly the same accuracy as the adiabatic connection fluctuation-dissipation theorem, but also rationalizes experimentally measured relative interfacial strengths of heterostructures and interlayer registry of hexagonal boron nitride that have plagued other vdW methods.

The finite element software ABAQUS is used to calculate and analyze the mechanical performance of cold-formed thin-walled curved channel steel members under horizontal reciprocating load. Double nonlinear finite element model needs to be considered, the influence of geometric imperfection and residual stress. The accuracy of the results was verified by comparing with the relevant test results. On the basis of controlling the main parameters such as width-thickness ratio, axial compression ratio, slenderness ratio and buckling mode, the numerical simulation results of 9 hysteretic specimens were selected to research the influence of the above factors on the hysteretic performance of the flexural members. The analysis results show that the width to thickness ratio, axial compression ratio and slenderness ratio have great influence on the hysteretic performance of the flexural members. The larger the three main parameters are, the worse the bearing capacity, ductility and energy consumption of the members will be. Therefore, the design should avoid as far as possible to choose a larger width-thickness ratio and slenderness ratio section components.

In this paper, we consider a new technique for variable order fractional functional differential equations (FDE for short). The proposed method relies on the reproducing kernel splines method (RKSM). The method can lessen computation cost and provide highly precise approximate solutions. Numerical results demonstrate that the algorithm is more effective and efficient.

Interfaces in Sb

Numerous defects may occur during the preparation of perovskite films, and these defects obstruct the charge transfer and accelerate the decomposition of films. Herein, the 1-propionate-4-amino-1,2,4-triazolium tetrafluoroborate (PATMBF4) is employed as a multifunctional additive for caesium (Cs), methylammonium (MA) and formamidinium (FA) triple-cation-based perovskites (CsFAMA) to prepare inverted planar solar cells. The amino group (-NH2) in PATM+ can donate free electron pair to form a Pb-N coordination bond with perovskite, which can not only regulate crystal growth, but also decrease the generation of charge recombination centers to make charge transfer more effective. The hydrogen bond formed between the carbonyl group (C O) contained in PATM+ and FA+ (O···H-N) restrains the migration of FA+ to the film surface, thus retarding the decomposition of film. Hence, the photoelectric conversion efficiency (PCE) of the champion device is as high as 21.35%. In addition, the PCE can sustain over 85% after exposure to air for 4000 h with a relative humidity of 40 ± 5%, and only drops by 10% in the case of 85 °C more than 1000 h (N2). It can retain 90% of PCE under the full-spectrum sunlight for 800 h (N2).

SnO2 is regarded as the most promising electron transporting layer (ETL) material for perovskite solar cells (PSCs). Various functional groups are introduced onto the SnO2 surface by interface modification with the purpose of improving the performance of the PSCs. However, most of the modifications are achieved in two-step approach, which are complicated and not easily realized. Here, we employ a facile one-step, low-temperature, and effective method to synthesis urea-complexed SnO2 ETL (referred as Urea-SnO2). The –NH2 groups on Urea-SnO2 attributes to facilitate the charge transfer within the SnO2 ETL and reduce trap state density in the perovskite film through the chemical interactions. Therefore, The PSCs based on the Urea-SnO2 ETL exhibit a champion power conversion efficiency (PCE) of 20.25%, which is more excellent than the devices based on the pristine SnO2 ETL (17.60%). Functionalization of SnO2 in situ by the precursor solution method offers an efficient method for high performance planar PSCs.

Solution treatment of perovskite films introduces many defects in the grain boundaries (GBs), which affects the power conversion efficiency (PCE) and long-term stability of the perovskite solar cells (PSCs). Designing suitable modification materials is the key to solving these problems. Herein, we synthesize the poly(styrene-co-acrylonitrile) polymer (PS-PAN polymer) through a facile polymerization method. The polymer successfully introduces nitrile (C≡N) into the PS chain and exhibits good thermal stability. When the PS-PAN polymer is added to the antisolvent to modify the perovskite film, it can passivate the GBs/surface defects and restrain the carrier recombination of the perovskite film. As a result, we obtain an enhanced PCE in inverted PSCs increasing from 18.18% to 22.02%. More importantly, the nonencapsulated PS-PAN-modified PSCs demonstrate good illumination and thermal stabilities and maintain 90% PCE under full-spectrum illumination at 75 °C in nitrogen glove box for 800 h. In addition, the designed device is resistant to moisture, retaining 91% PCE in air (50 ± 5% relative humidity) for 4000 h.

Focusing on the chemiluminescent properties of the flame is an effective way to study the flame structure and reaction mechanism. In this paper, based on the CCD camera imaging system, the chemiluminescent distributions of OH* and CH* in CH4/O2 diffusion flames with different global equivalence ratios and CO2 dilution levels were obtained. The changes in the reaction zones of OH* layer and CH* layer were further compared. The peak intensity ratios of OH* and CH* were used to quantitatively characterize the global equivalence ratio and the CO2 dilution level. The results show that variations in the global equivalence ratio and the CO2 dilution level do not obviously alter the shape and thickness of the CH* layer. The distribution and intensity changes of the OH* layer are much more significant than those of the CH* layer when the experimental conditions are varied. For the flame with a low dilution level, the CH* layer is located on the inner rim of the OH* layer, and the radial positions of two peaks are not much different. The increase of the CO2 dilution level leads to the displacement of the OH* peak, which becomes closer to the flame axis. In addition, due to the narrowing of the OH* layer, the CH* layer eventually becomes at the outer rim of the OH* layer. The peak intensity ratio of OH* and CH* decreases linearly with the rise of the global equivalence ratio, and changes as a power function with the increasing CO2 dilution level.

A kind of Y-bearing ferritic/martensitic fuel cladding tube with qualified dimensions, acceptable mechanical properties as well as good flattening and flaring performance was manufactured recently by our group. In this paper, to improve and further evaluate its oxidation resistance, the cladding tube was aluminized firstly and then subjected to high temperature steam oxidation at 1200 °C for 8 h. The results indicated that aluminizing coating with gradient content of Al was prepared on the tube successfully. And the matrix microstructure was transformed from tempered martensite into ferrite during aluminizing. Weight gains after high temperature steam oxidation were 72.7 and 1.48 mg cm−2 for the bare and aluminized tubes, respectively. The latter one exhibited better oxidation resistance due to the generated dense aluminum oxide film. Meanwhile, Kirkendall pores were formed near oxidation surface and should be eliminated for the real application of the aluminized tube in the future.

Stacked graphene platelet nanofibers (SGNF) dispersed in the electrolyte of dye-sensitized solar cells (DSSCs) can efficiently improve the charge transport and catalytic reactions of the Co(III)/(II) redox couple so that the quinoxaline dye AQ308-based DSSC containing 0.2 mg mL−1 SGNF exhibits the best power conversion efficiency (PCE) of 9.81%.

A series of new pyrido[3,4-b]pyrazine-based organic sensitizers (PP-I and APP-I–IV) containing different donors and π-spacers have been synthesized and employed in dye-sensitized solar cells (DSSCs). The absorption spectra properties of dyes are analysed by density functional theory (DFT). The calculated results in combination with the experiments suggest that the absorption characteristics and excited state features will mainly be dominated by charge transfer transitions from the highest occupied molecular orbital (HOMO) to the lowest unoccupied molecular orbital (LUMO) and to higher LUMO orbitals. Furthermore, attaching the octyloxy groups significantly extends the π-conjugation of the donor in APP-IV, which raises the HOMO energy and facilitates its oxidation. As a consequence, APP-IV exhibits the lowest HOMO–LUMO energy gap among all dyes, which, in turn, corresponds well with the red shift of the absorption spectra. Transient photovoltage and photocurrent decay experiments as well as electrochemical impedance spectroscopy indicate that the electron lifetime and charge recombination resistance are increased due to the introduction of octyloxy chains on the donor unit, resulting in the high photovoltage based on APP-IV. It was found that APP-IV based DSSCs with liquid electrolyte display the highest power conversion efficiency (PCE) of 7.12%. Importantly, a PCE of 6.20% has been achieved for APP-IV based DSSCs with ionic-liquid electrolytes and retained 97% of the initial value after continuous light soaking for 1000 h at 60 °C. This renders these pyrido[3,4-b]pyrazine-based sensitizers quite promising candidates for highly efficient and stable DSSCs.

Thin wall cladding tubes of yttrium-bearing 9Cr ferritic-martensitic steel have been fabricated by cold-rolling process, with the final dimensions of 6 mm outer diameter, 0.5 mm thickness and 3 m length. The changes of microstructure of hot-rolled plate, forged rod and the final tubes were attributed to the cold-rolling process and the intermediate heat treatment. Mechanical properties were tested from room temperature to 600 °C. The final tubes showed the strength level between the traditional ferritic-martensitic steel and the metallurgy alloyed oxide dispersion strengthened steel. It was also found that the degradation of ductility at 400 °C was related to the dynamic strain ageing (DSA) effect. At last, ultra-sound test, flattening test and flaring test were carried out to evaluated the qualities of the final tubes.

Two new thiocarbonyl quinacridone compounds (TQA-H and TQA-TPA) were designed and synthesized, and their fluorescent behaviors toward various metal ions were investigated. The measurements of sensing behavior to various metal ions reveal that both of them are excellent “turn on” fluorescent chemosensors for mercury ion. Addition of Hg2+ to the chloroform solution of TQA-TPA gave the lowest detection limit at 4.7 nM. In addition, colorimetric changes of sensors interacted with Hg2+ are also successfully demonstrated. The recognition is attributed to Hg2+-induced conversion of thiocarbonyl quinacridones into their carbonyl analogues.

The effects of chenodeoxycholic acid (CDCA) in a dye solution as a co-adsorbent on the photovoltaic performance of dye-sensitized solar cells (DSSCs) based on two organic dyes containing phenothiazine and triarylamine segments (P1 and P2) were investigated. It was found that the coadsorption of CDCA can hinder the formation of dye aggregates and improve electron injection yield and thus Jsc. This has also led to a rise in photovoltage, which is attributed to the decrease of charge recombination. The DSSC based on dye P2 showed better photovoltaic performance than P1: a maximum monochromatic incident photon-to-current conversion efficiency (IPCE) of 89.5%, a short-circuit photocurrent density (Jsc) of 9.57 mA/cm2, an open-circuit photovoltage (Voc) of 697 mV, and a fill factor (FF) of 0.66, corresponding to an overall conversion efficiency of 4.42% under the standard global AM 1.5 solar light condition. The overall conversion efficiency was further improved to 5.31% (Jsc = 10.36 mA/cm2, Voc = 0.730 V, FF = 0.70) upon addition of 10 mM CDCA to the dye solution for TiO2 sensitization. Electrochemical impedance data indicate that the electron lifetime was improved by coadsorption of CDCA, accounting for the significant improvement of Voc. These results suggest that interfacial engineering of the organic dye-sensitized TiO2 electrodes is important for highly efficient photovoltaic performance of the solar cell.

Two new linear and hyperbranched conjugated polymers P1 and P2 have been synthesized by Sonogashira coupling reaction, in which the main chain consists of bithiazole moieties as electron acceptors and triphenylamino groups as donors. The conjugated polymers were characterized by TGA, UV–vis absorption, fluorescence emission, electrochemical cyclic voltammetry, and two-photon absorption measurements. They exhibited excellent solubility in organic solvents and high thermal stability (5% of weight loss at 299 °C). The two-photon absorption cross sections (σ) measured by the open aperture Z-scan technique using 140 femtosecond (fs) pulse were determined to be 1014 and 552 GM per repeating unit for P1 and P2, respectively. This result shows that the σ of linear conjugated P1 is higher than that of hyperbranched P2, indicating that the linear polymer offers better intramolecular charge transfer ability. In THF, P1 and P2 exhibit intense frequency up-converted fluorescence under the excitation of 140 fs pulses at 800 nm with the peaks located at 580 and 548 nm, respectively. Meanwhile, the optical limiting behaviors for the polymers were studied by using a focused 800 nm laser beam of 140 fs duration. It was found that these polymers also exhibit good optical-limiting properties and make them potential candidates for optical limiters in the photonic fields. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

As research interest moves from micromaterials to nanomaterials and quantum structures, the surface energy of the structures has an increasing impact on the nanomaterial growth and its properties. In terms of the nanowire research field, the role of surface energy has been debated for years since both surface energy and supersaturation in droplets play a role in affecting nanowire growth, making it challenging to distinguish the role of surface energy from supersaturation. Recent advances in nanowire research have gradually revealed that surface energy, which was underestimated in the past, is as important as supersaturation during nanowire growth. Here, this review discusses the available basic concepts and thermodynamic models about surface energy in determining nanowire growth. Recent experimental findings show that surface energy can determine the nanowire growth phenomenon, including nanowire growth direction, morphology, crystal polytype, axial and lateral heterostructure. The impact of surface energy for both nanowire growth mechanisms, vapor–liquid–solid and vapor–solid, are discussed. Through this review, the aim is to clarify the current understanding of surface energy in nanowire growth and build a knowledge pool for future nanostructure and quantum structure synthesis using a surface energy engineering process.

Dye-sensitized solar cells (DSSCs) with cobalt electrolytes have gained increasing attention. In this Research Article, two new pyrido[3,4-b]pyrazine-based sensitizers with different cores of bulky donors (indoline for DT-1 and triphenylamine for DT-2) were designed and synthesized for a comparative study of their photophysical and electrochemical properties and device performance and were also analyzed through density functional theory calculations. The results of density function theory calculations reveal the limited electronic communication between the biphenyl branch at the cis-position of N-phenylindoline and the indoline core, which could act as an insulating blocking group and inhibit the dye aggregation and charge recombination at the interface of TiO2/dye/electrolyte. As expected, DSSCs based on DT-1 with cobalt redox electrolyte gained a higher photoelectric conversion efficiency of 8.57% under standard AM 1.5 G simulated sunlight, with Jsc = 16.08 mA cm(-2), Voc = 802 mV, and FF = 0.66. Both electrochemical impedance spectroscopy (EIS) and intensity-modulated photovoltage spectroscopy (IMVS) suggest that charge recombination in DSSCs based on DT-1 is much less than that in their counterparts of DT-2, owing to the bigger donor size and the insulating blocking branch in the donor of DT-1.

Epidermal growth factor (EGF) ameliorates stress and prevents incomplete gastrointestinal development in early-weaned piglets in commercial swine farming. This study aimed to further analyze the biological activities of intracellularly expressed EGF (IE-EGF), extracellularly expressed EGF (EE-EGF), and tagged EGF (T-EGF) from Saccharomyces cerevisiae in early-weaned pigs. In this study, we assigned 24 pigs to each of 5 groups that were provided a basic diet (the control group) or a diet supplemented with empty vector-expressing S. cerevisiae [the INVSc1(EV) group], T-EGF-expressing S. cerevisiae [the INVSc1-TE(-) group], EE-EGF-expressing S. cerevisiae [the INVSc1-EE(+) group], or IE-EGF-expressing S. cerevisiae [the INVSc1-IE(+) group]. All treatments were delivered at a dose of 60 μg EGF/kg body weight (BW) everyday. All the piglets were sacrificed after 21 day to determine their physio-biochemical indexes, immune functions, and intestinal development. In the piglet experiments, recombinant S. cerevisiae survived throughout the intestinal tract. The BW and intestinal development (e.g., mean villous height, crypt depth, villous height:crypt depth ratio (IVR), and total protein, DNA, and RNA contents) of the piglets were significantly enhanced in the INVSc1-IE(+) group compared with the animals in the INVSc1-EE(+) and INVSc1-TE(-) groups (P 0.05). In addition, increased proliferating cell nuclear antigen (PCNA) staining was observed in the piglets that received the INVSc1-IE(+) treatment (approximately 80 %) compared with those that received the INVSc1-TE(-) (approximately 70 %) and INVSc1-EE(+) treatments (approximately 70 %). The levels of lactate dehydrogenase (LDH), creatine kinase (CK), alkaline phosphatase (ALP), immunoglobulin A (IgA), immunoglobulin M (IgM), and immunoglobulin G (IgG) were also significantly increased in the INVSc1-IE(+) group compared with the INVSc1-EE(+) and INVSc1-TE(-) groups (P 0.05). Furthermore, the proliferation of piglet enterocytes was also significantly stimulated by both IE-EGF and EE-EGF compared with T-EGF in vitro (P 0.05). Our data further demonstrate the previously reported hypothesis that IE-EGF is more suitable than EE-EGF or T-EGF for applications in early-weaned pigs.

Epidermal growth factor (EGF) ameliorates stress and prevents incomplete gastrointestinal development in early-weaned piglets in commercial swine farming. This study aimed to further analyze the biological activities of intracellularly expressed EGF (IE-EGF), extracellularly expressed EGF (EE-EGF), and tagged EGF (T-EGF) from Saccharomyces cerevisiae in early-weaned pigs. In this study, we assigned 24 pigs to each of 5 groups that were provided a basic diet (the control group) or a diet supplemented with empty vector-expressing S. cerevisiae [the INVSc1(EV) group], T-EGF-expressing S. cerevisiae [the INVSc1-TE(−) group], EE-EGF-expressing S. cerevisiae [the INVSc1-EE(+) group], or IE-EGF-expressing S. cerevisiae [the INVSc1-IE(+) group]. All treatments were delivered at a dose of 60 μg EGF/kg body weight (BW) everyday. All the piglets were sacrificed after 21 day to determine their physio-biochemical indexes, immune functions, and intestinal development. In the piglet experiments, recombinant S. cerevisiae survived throughout the intestinal tract. The BW and intestinal development (e.g., mean villous height, crypt depth, villous height:crypt depth ratio (IVR), and total protein, DNA, and RNA contents) of the piglets were significantly enhanced in the INVSc1-IE(+) group compared with the animals in the INVSc1-EE(+) and INVSc1-TE(−) groups (P

A new quinoxaline-fused tetrathiafulvalene-based sensitizer has been prepared and characterized. The resulting power conversion efficiency of 6.47% represents the best performance to date for tetrathiafulvalene-sensitized solar cells.

We report two new molecularly engineered push-pull dyes, i.e., YA421 and YA422, based on substituted quinoxaline as a π-conjugating linker and bulky-indoline moiety as donor and compared with reported IQ4 dye. Benefitting from increased steric hindrance with the introduction of bis(2,4-dihexyloxy)benzene substitution on the quinoxaline, the electron recombination between redox electrolyte and the TiO2 surface is reduced, especially in redox electrolyte employing Co(II/III) complexes as redox shuttles. It was found that the open circuit photovoltages of IQ4, YA421, and YA422 devices with cobalt-based electrolyte are higher than those with iodide/triiodide electrolyte by 34, 62, and 135 mV, respectively. Moreover, the cells employing graphene nanoplatelets on top of gold spattered film as a counter electrode (CE) show lower charge-transfer resistance compared to platinum as a CE. Consequently, YA422 devices deliver the best power conversion efficiency due to higher fill factor, reaching 10.65% at AM 1.5 simulated sunlight. Electrochemical impedance spectroscopy and transient absorption spectroscopy analysis were performed to understand the electrolyte influence on the device performances with different counter electrode materials and donor structures of donor-π-acceptor dyes. Laser flash photolysis experiments indicate that even though the dye regeneration of YA422 is slower than that of the other two dyes, the slower back electron transfer of YA422 contributes to the higher device performance.

Two new near-infrared chemodosimeters for cyanide anion based on 5,10-dihexyl-5,10-dihydrophenazine were designed and synthesized. With dicyano-vinyl groups as the recognition site and electron-withdrawing groups on both sides, probe 1 exhibited an intramolecular charge transfer (ICT) absorption band at 545 nm and emission band at 730 nm, respectively, and thus showed an ICT block process and realized an "on-off" response after bilateral reaction with cyanide anions in CH₃CN. Probe 2 utilized an unreactive formyl group instead of one of the two reactive dicyano-vinyl groups as the electron-withdrawing component. Due to the unilateral recognition process the ICT of probe 2 was redirected and lead to a remarkably colorimetric and ratiometric near-infrared (NIR) fluorescent response for cyanine. Both probes provided high sensitivity and selectivity with apparent response signals which can be observed by naked eyes, even in the copresence of various other interference anions. Optical spectroscopic techniques, NMR titration measurements, and density functional theory calculations were conducted to rationalize the sensing mechanisms of these two probes.

A series of new push-pull or- ganic dyes (BT-I-VI), incorporating electron-withdrawing bithiazole with a thiophene, furan, benzene, or cyano moiety, as p spacer have been synthe- sized, characterized, and used as the sensitizers for dye-sensitized solar cells (DSSCs). In comparison with the model compound T1, these dyes con- taining a thiophene moiety between tri- phenylamine and bithiazole display en- hanced spectral responses in the red portion of the solar spectrum. Electro- chemical measurement data indicate that the HOMO and LUMO energy levels can be tuned by introducing dif- ferent p spacers between the bithiazole moiety and cyanoacrylic acid acceptor. The incorporation of bithiazole substi- tuted with two hexyl groups is highly beneficial to prevent close p-p aggre- gation, thus favorably suppressing charge recombination and intermolecu- lar interaction. The overall conversion efficiencies of DSSCs based on bithia- zole dyes are in the range of 3.58 to 7.51 %, in which BT-I-based DSSCs showed the best photovoltaic perform- ance: a maximum monochromatic inci- dent photon-to-current conversion effi- ciency (IPCE) of 81.1 %, a short-circuit photocurrent density (Jsc )o f 15.69 mA cm 2 , an open-circuit photo- voltage (Voc) of 778 mV, and a fill factor (ff) of 0.61, which correspond to an overall conversion efficiency of 7.51 % under standard global AM 1.5 solar light conditions. Most important- ly, long-term stability of the BT-I-III- based DSSCs with ionic-liquid electro- lytes under 1000 h of light soaking was demonstrated and BT-II with a furan moiety exhibited better photovoltaic performance of up to 5.75 % power conversion efficiency.

Five new multi-branched two-photon absorption triazine chromophores (T1-T5) with different donor strength, conjugation length, and direction of charge transfer have been designed and synthesized. The one-photon fluorescence, fluorescence quantum yields, and two-photon properties have been investigated. The two-photon absorption (2PA) cross sections measured by the open aperture Z-scan technique were determined to be 447, 854, 1023, 603, and 766 GM for T1, T2, T3, T4, and T5, respectively. This result indicates that their 2PA cross section values (σ) increase with increasing electron-donating strength of the end group, extending the conjugation length of the system, and introducing electron-withdrawing perfluoroalkyl as side groups to the end donor. In addition, the σ value of T5 is also larger than that of T1, which provides evidence that the σ value is relative to the direction of charge transfer (from the ends to the center of the molecule or from the center to the ends). Moreover, significant enhancement of the two-photon absorption cross section was achieved by introducing a thiophene moiety to a conjugated C==C bond. At the same time, the optical limiting behavior for these chromophores was studied by using a focused 800 nm laser beam with pulses of 140 fs duration. It was found that these molecules also exhibit good optical limiting properties. These initial results clearly demonstrate that multi-branched triazine chromophores are a highly suitable class of two-photon absorbing materials.

In this work, three new quinacridone-based dyes containing a furan moiety (QA1–3) have been synthesized through simple synthetic routes for the application of dye-sensitized solar cells (DSSCs). Their absorption spectra, electrochemical, photovoltaic properties and the cell long-term stability have been extensively investigated. Electrochemical measurement data indicates that the tuning of the HOMO and LUMO energy levels can be conveniently realized by alternating the donor moiety. The theoretical calculations show that the dihedral angle between the quinacridone moiety and the furan ring is less than 1 degree, indicating excellent planarity between the two groups, which is beneficial for intramolecular charge transfer. All of these dyes performed as sensitizers for DSSCs tested under similar AM 1.5 experimental conditions, and a maximum solar energy to electricity conversion efficiency of 7.70% (Jsc = 13.25 mA cm−2, Voc = 804 mV, FF = 0.73) for the 20 mM chenodeoxycholic acid (CDCA) co-adsorbed DSSCs based on QA1 is obtained. Electrochemical impedance experiments indicate that the electron lifetime is improved by co-adsorption of CDCA, accounting for the significant improvement of Voc. Most importantly, the long-term stability of the QA1–3-based DSSCs with ionic-liquid electrolytes under 1000 h light-soaking has been demonstrated.

Three new phenothiazine organic dyes containing thiophene, 3-(5-(3-(4-(bis(4-methoxy phenyl)amino)phenyl)-10-octyl-10H-phenothiazin-7-yl)thiophen-2-yl)-2-cyanoacrylic acid (P1), 3-(5-(3-(4-(diphenylamino)phenyl)-10-octyl-10H-phenothiazin-7-yl)thiophen-2-yl)-2-cyanoacrylic acid (P2) and 2-cyano-3-(5-(10-octyl-3-(4-(2,2-diphenylvinyl)phenyl)-10H-phenothiazin-7-yl)thiophen-2-yl) acrylic acid (P3) were designed and synthesized as sensitizers for application in dye-sensitized solar cells (DSSCs). For these dyes, the phenothiazine derivative moiety and the cyanoacetic acid take the roles of electron donor and electron acceptor, respectively. The absorption spectra, electrochemical and photovoltaic properties of P1–P3 and the cell long-term stability were extensively investigated. It was found that HOMO and LUMO energy level tuning can be conveniently accomplished by alternating the donor moiety. The DSSCs based on dye P2 showed the best photovoltaic performance: a maximum monochromatic incident photon-to-current conversion efficiency (IPCE) of 84.9%, a short-circuit photocurrent density (Jsc) of 10.84 mA cm−2, an open-circuit photovoltage (Voc) of 592 mV, and a fill factor (ff) of 0.69, corresponding to an overall conversion efficiency of 4.41% under standard global AM 1.5 solar light conditions. These results demonstrated that the DSSCs based on phenothiazine dyes could achieve both high performance and good stability.

The inward diffusion of metal electrodes is one of the main reasons for the deterioration of the long-term device stability of perovskite solar cells (PSCs). Thus, herein, we adopt a simple additive engineering strategy to modify the barrier material bathocuproine (BCP) with 1,3,5-triazine-2,4,6-trithiol trisodium salt (TTTS). Different from the traditional physical blocking strategies, TTTS could prevent the metal electrodes (e.g., gold, silver, and copper) from diffusing inward through the strong chemical coordination between TTTS and the metal electrode. The TTTS additive also improved the conductivity and band structure of BCP, thus enhancing the ability of BCP to extract electrons from the perovskite layer to the electrode. Consequently, the inverted device modified with TTTS exhibited a high efficiency of 22.59%, which is among the highest efficiencies reported to date for inverted PSCs. More importantly, it showed excellent operational, ambient, and thermal stability. The target device maintained its initial efficiency with no loss under continuous one-sun illumination at maximum power point tracking after 1000 h (the champion device), 91% in air (50% +/- 5% RH) for 5000 h, and 93% after heating at 85 degrees C for 1500 h (average efficiency from ten devices).

The inferior power conversion efficiency (PCE) compared to their regular counterparts (n-i-p) and undesirable stability issues of inverted (p-i-n) perovskite solar cells (PSCs) are the foremost issues hindering their commercialization. Here, for the first time, we demonstrate a polymeric room-temperature molten salt (poly-RTMS), namely poly(1-vinyl-3-ethyl-acetate) imidazole tetrafluoroborate (PEa), as a novel type of additive to modulate the perovskite crystallization and its electronic properties. The PEa poly-RTMS containing multiple chemical anchoring sites along with strong bonding stability can firmly bond to Pb ion defects at grain boundaries and the interface of the perovskite film via coordination bond, which effectively passivates the electronic defects and enhances the photo-, thermal-, and moisture-stability of perovskite films. As a result, the PEa-modified inverted PSCs show striking performance improvements over the control with the PCE exceeding 21.4% and excellent long-term operational stability, maintaining over 92% of the initial efficiency for 1200 hours under continuous full sun illumination at 70-75 degrees C. This strategy opens a new avenue to modulate the properties of perovskites for optoelectronic applications.

Two new [1,2,5]thiadiazolo[3,4-c]pyridine-containing D-A-pi-A organic dyes (PT-1 and PT-2) have been designed and synthesized for utilization in dye-sensitized solar cells. PT-2 sensitizer, which was synthesized by incorporating the 4,4-bis(2-ethylhexyl)-4H-cyclopenta[1,2-b:5,4-b']dithiophene moiety as an additional pi-bridge into the organic sensitizer PT-1, not only brings about significant changes in the absorption spectrum but also suppresses the charge recombination rate as compared to PT-1. Moreover, PT-2 exhibits an aesthetic blue color covering a broad spectral range into the NIR region. The incident-photon to electron-conversion efficiency of PT-2 shows an onset approaching 850 nm with power conversion efficiency of 6.796 fabricated when utilizing an iodide-based redox electrolyte. These results demonstrate that these [1,2,5]thiadiazolo[3,4-c]pyridine-based sensitizers are quite promising candidates to use for lowering the HOMO-LUMO gap and shifting the spectral response toward the NIR.