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It is of great significance to study the treatment of organic dye pollution. In this work, a method of electrochemical treatment for reactive blue 19 dye (RB19) wastewater system was established, and it was applied to the actual dye wastewater treatment. The effects of applied voltage, electrolyte concentration, electrode spacing, and initial concentration on the removal effect of RB19 have been studied in detail. The results show that the removal rate of RB19 can reach 82.6% and the chemical oxygen demand (CODcr) removal rate is 54.3% under optimal conditions. The removal of RB19 in the system is mainly the oxidation of hydroxyl free radicals. The possible degradation pathway is inferred by ion chromatography: hydroxyl free radicals attack the chromophoric group of RB19 to make it fall off, and then decompose it into ring-opening. The product is finally oxidized to CO2 and water. The kinetic fitting is in accordance with the zero-order reaction kinetics. At the same time, using the established electrochemical system to treat the actual dye wastewater has also achieved good results. After 3 hours of treatment, the CODcr removal rate of the raw water is 44.8%, and the CODcr removal of the effluent can reach 89.5%. The degradation process conforms to the zero-order reaction kinetics. The result is consistent with the electrochemical treatment of RB19.

Among the factors that lead to the reduction of the efficiency of perovskite solar cell (PSCs), is the difficulty involved in realizing a high-quality film and the efficient charge transfer that take place at the interface between electron-transport layer (ETL) and perovskite. Here, we demonstrated a strategy for planar-type devices by natural bio-functional interfaces that uses a buried electron-transport layer made of cobalamin complexed tin oxide (SnO2@B12). As systematically investigating the effects of SnO2@B12 interfacial layer in perovskite solar cells, cobalamin can chemically link SnO2 layer and perovskite layer, resulting in improved perovskite film quality and interfacial defect passivation. Utilizing SnO2@B12 improves the efficiency of planar-type PSCs by 20.60 %. Furthermore, after 250 hours of exposure to an ambient atmosphere, unsealed PSCs containing SnO2@B12 degrade by 10%. This research provides a viable method for developing bio-functional molecules that will increase the effectiveness and durability of planar-perovskite solar cells.

Sb2Se3 is an emerging and promising thin-film photovoltaic absorber material. However, for commonly CdS/Sb2Se3 heterojunction device structure, low carrier concentration and back contact barrier will prevent the further improvement of device efficiency. Here we have successfully applied Cu2ZnSnS4 (CZTS) nanoparticles (NPs) as a hole-transport layer (HTL) to construct a low-cost n-i-p Sb2Se3 solar cell with FTO/CdS/Sb2Se3/CZTS/Carbon configuration. We found that CZTS HTL can effectively suppress the back interface carrier recombination and improve carrier collection efficiency in the Sb2Se3 solar cells. The average Jsc, FF, and efficiency of Sb2Se3 solar cells with an optimum CZTS HTL are increased by 10.64%, 7.91%, and 17.14%, respectively, compared with Sb2Se3 solar cells without a HTL. Consequently, with CZTS NPs as HTL and carbon as electrode, the n-i-p Sb2Se3 solar cells have achieved a champion efficiency of 6.06%.

Cu2ZnSnS4 nanocrystal is a highly potential inorganic hole conducting material for perovskite solar cells employing low temperature carbon electrodes, which exhibit great prospect in future commercialization. However, Cu2ZnSnS4 nanocrystals are most commonly synthesized using the hot-injection method, which is not suitable for mass production. Here, a scalable one-step heating up synthesis method is demonstrated to successfully produce Cu2ZnSnS4 nanocrystals. First, the reaction time is optimized to be 60 min after evaluating the performances of perovskite solar cell employing the small-batch synthesized Cu2ZnSnS4 nanocrystals with different reaction time. Then, gram-scale Cu2ZnSnS4 nanocrystals are successfully synthesized under the optimized reaction time. Using these gram-scale synthesized Cu2ZnSnS4 nanoparticles, the best-performing perovskite solar cell can demonstrate a power conversion efficiency of 16.10%.

The rising incidence of ulcerative colitis has become a new challenge for public health. Chimonanthus nitens Oliv. leaf granule (COG) is a natural medicine used for the treatment of respiratory diseases, which has excellent anti-inflammatory and antioxidant effects. However, the therapeutic effect of COG in ulcerative colitis (UC) has not been reported. Here, the experimental colitis was treated with dextran sodium sulfate (DSS) and COG. After treatment with high (30 g/kg), medium (15 g/kg), and low (7.5 g/kg) doses of COG for 11 consecutive days, the body weight, disease activity index (DAI) score, colon length, colon weight index, and the pathological score of mice were effectively improved. COG significantly reduced the levels of inflammatory cytokines in UC mice in vitro and in vivo and restored the secretion levels of IL-6 and IL-10 in the colon. Meanwhile, compared to mice with colitis, COG-treated mice showed lower levels of MDA, MPO, NO, and eNOS and higher levels of GSH-Px and MAO, which indicated that oxidative stress damage in colitic mice was alleviated by COG. Moreover, less Th17 and more Tregs were observed in the COG-treated groups. In addition, COG improved the diversity and relative abundance of gut microflora in the colon of colitic mice, and Lachnospiraceae_NK4A136_group and Lachnospiraceae_UCG-006 were obviously regulated at the genus level. In summary, COG has a protective effect on DSS-induced experimental colitis, mainly through inhibition of immune-inflammatory responses and oxidative stress and regulation of mTreg cell responses and intestinal flora composition.

Power conversion efficiency and stability of perovskite solar cells are greatly influenced by the defects of the perovskite films. To enhance the performance of perovskite solar cells, the defects of perovskite films should be effectively passivated. In this work, we provide an easy and feasible method to passivate the defects of perovskite films using chlorobenzene/perylene mixed anti-solvent. The validity of the defects passivation is confirmed experimentally. Under the optimized concentration, chlorobenzene/perylene mixed anti-solvent can boost the power conversion efficiency of the perovskite solar cells to 19.42%, which is 13.63% higher than the reference solar cells (17.09%). A champion power conversion efficiency of 20.05% is also demonstrated.

Manipulating the structure of Bi-based pyrochlores can produce excellent physicochemical properties and novel phenomena due to lattice disorders and distortions. Herein, bismuth iron niobate pyrochlores via high-level Co-doping were successfully fabricated by a sol-gel auto-combustion method and the doping effects on their structural, magnetic, dielectric and sonocatalytic properties were systematically investigated. Rietveld refinements revealed substituting Fe sites with Co ions (at a ratio of 30%–80%) can maintain the pyrochlore phase and induce larger lattice distortion. New dielectric relaxation and outstanding magneto-dielectric effect with a maximal 4% coefficient were clearly observed in the heavily Co-doped sample at low temperatures, which correlate with structural disorder and magnetic state transitions. New types of dielectric anomalies that gradually change the relative permittivity but maintain the dielectric loss almost constant with increasing temperature or frequency and can be tuneable at different doping levels were first observed above room temperature. The activation of ultrasonic vibration-driven degradation in the specimens was evaluated by the catalytic oxidation of dye, and the Fe/Co-coexisting catalysts exhibited superior sonocatalytic activity with magnetic recyclability, opening up a new pathway of developing feature-rich pyrochlores in the catalytic field.

Among the factors that lead to the reduction of the efficiency and stability of perovskite solar cells (PSCs) using [6,6]-phenyl C61 butyric acid methyl ester (PCBM) versus those of conventional structure, is the difficulty involved in realizing a high-quality film, and the non-radiative recombination that takes place at the interface between PCBM and perovskite. Our present work proposes a fabrication technique capable of overcoming these issues. Organic small molecule material was introduced along with PCBM, to obtain a homogeneously seamless film that plays the role of a dipole layer. The incorporated triethyl citrate (TEC) boosts the power conversion efficiency (PCE) from 14.56% to 17.86% with suppressed hysteresis, which originates primarily from the efficient electron transfer between the perovskite/PCBM and the Ag cathode interface. The results of electrochemical impedance spectroscopy measurements imply efficient electron transfer, low series resistance, and large recombination resistance in the photovoltaic device employing PCBM@TEC as the cathode interfacial layer. Specifically, the highly hydrophobic PCBM@TEC cathode interfacial layer (CIL) showed higher resistance to moisture, leading to a more environmentally-stable device. The results also showed the efficiency of the device retained 84% of its initial value after 30 days of operation under ambient conditions, which shows a visibly superior stability compared to a reference device that, under the same environment, retained only 37% its initial efficiency. Such advancement in the operational efficiency and stability of the device, will contribute to the longevity and cost-effectiveness of inverted PSC devices.

p-GeSe is a promising absorber material for thin-film solar cell. In this letter, p-GeSe thin films were fabricated by post-annealing treatment of a-GeSe films. We systematically studied the effects of annealing time on the crystallinity, surface morphology and photoelectric properties of GeSe films, and we found the bandgaps, optical constant and conductivity of GeSe films have shown significant variations when GeSe films transformed from amorphous to polycrystalline. The bandgap of GeSe film can be tuned in a range of 1.17–1.42 eV and the hole mobility can reach as high as 15.02 cm2 V−1 s−1. Finally, a thin-film solar cell based on FTO/CdS/p-GeSe/Au configuration was fabricated and has realized an efficiency of 0.65% and a short circuit current of 12.61 mA/cm2.

Cu2ZnSnS4 (CZTS) nanoparticles have been demonstrated to be a potential hole transporting material for low temperature paintable carbon electrode based perovskite solar cells, yet the reported power conversion efficiency is not satisfactory. Hot injection synthesized CZTS nanoparticles are usually capped with long chain oleylamine, which hampers the charge transportation between CZTS nanoparticles. It is reported that replacing the long chain oleylamine with short chain organic ligand can promote the charge transportation of CZTS nanoparticles. Here, we have demonstrated that CZTS nanoparticles with hexanethiol modification exhibit superior charge transportation properties, which results in better hole extraction capability of the CZTS nanoparticles. Therefore, power conversion efficiency of MAPbI3 perovskite solar cells employing CZTS hole transporting layer and low temperature paintable carbon electrode is boosted from 14.27% for pristine CZTS nanoparticles to 16.62% for the modified CZTS nanoparticles. When FAPbI3 is used as alternative light absorbing layer, a champion power conversion efficiency of 17.71% is obtained, which is among one of the highest PCEs for perovskite solar cells employing an inorganic hole transporting layer and a carbon electrode.

Proper valence band offset at the perovskite/hole transport material interface is critical to obtain high performance perovskite solar cells. The Cu2ZnSn(Se1-xSx)4 compound is a potential candidate of hole transport material for perovskite solar cells and exhibits tunable band gap from 0.95 eV for Cu2ZnSnSe4 to 1.5 eV for Cu2ZnSnS4 with different S/(S+Se) ratio, which offers a feasible approach to engineering the valence band offset at the perovskite/Cu2ZnSn(Se1-xSx)4 interface. Here, the valence band offset engineering at the perovskite/Cu2ZnSn(Se1-xSx)4 interface is studied through numerical simulation with SCAPS package. The valence band offset can be tuned from negative value to positive value with different Cu2ZnSn(Se1-xSx)4 composition. With optimized S concentration, a suitable valence band offset (0.27 eV) is obtained, leading to a power conversion efficiency of 20.25%. Further optimization of thickness, defect density, and acceptor density of the Cu2ZnSn(Se1-xSx)4 transport layer is conducted, and power conversion efficiency of 20.77% is obtained. This study here provides a guidance to further optimize the performance of perovskite solar cells with Cu2ZnSn(Se1-xSx)4 hole transport material.

Employing additive to regulate the morphology of perovskite film is an effective method to enhance both the power conversion efficiency and long term stability of organic-inorganic hybrid perovskite solar cells. Here, we demonstrate that guanidinium thiocyanate (GuSCN) is a suitable additive for methylammonium lead iodide (MAPbI3) perovskite materials. Addition of GuSCN into MAPbI3 can simultaneously enhance the crystallinity, enlarge the crystal size, and reduce the trap density of the perovskite films. As a result, the MAPbI3 perovskite with 10% GuSCN exhibits superior power conversion efficiency of 16.70% compared to the pristine MAPbI3 perovskite solar cell (15.57%). At the same time, the MAPbI3 perovskite solar cell with GuSCN additive shows better stability, power conversion efficiency retains ∼90% of its initial value compared to only ∼60% for pristine MAPbI3 perovskite solar cells after being stored for 15 days without encapsulation.

Bismuth-based pyrochlore oxides in which the structure tolerates significantly lower site misplacement and markedly higher vacancy concentrations exhibit unique physicochemical properties; therefore, manipulation of such a crystal structure by chemical substitution may give rise to intriguing phenomena and extraordinary properties. Herein, we have systematically investigated the effects of the Co substitution on the structural, magnetic, magneto-dielectric and optoelectronic characteristics of ternary bismuth iron niobate pyrochlore oxide with the highest recorded Fe content. Structural modulation induced by the Co dopant was clearly observed by Rietveld refinements and Raman spectra, which are attributed to the displacive disorder nature of the pyrochlore structure and lattice distortions induced by the substitution of Fe sites with Co ions. A dielectric anomaly exhibits a distinct peak temperature shift and intensity increasing under a magnetic field of 1 T, which may be explained in terms of the magnetic state transition and magnetic interactions or fluctuations, and the obvious magneto-dielectric (MD) effect with a maximal MD coefficient of ∼4% at ∼1 MHz was firstly found in ferroelectric Bi pyrochlores. Remarkably, the Fe/Co-coexisted nanoparticles showed an anomalous light absorption and exhibited an enhanced visible-light-responsive photocatalytic performance by means of the dye decomposition and the photoelectrochemical technique. The findings indicated structural modulation using element substitution can realize excellent physicochemical behaviours and novel phenomena and shed new light on controlling the atomic structure and functional properties in isostructural pyrochlore oxides.

In this paper, a novel one-step solution approach is developed to prepare high quality methylammonium lead trihalide (MAPbI3) perovskite films. This approach employs methanol as additive, which is added into the perovskite precursor solution. The use of methanol can enhance the absorption of MAPbI3 and significantly improve the coverage of MAPbI3 on a planar substrate. The fabricated perovskite solar cell (PSC) with methanol exhibits a higher power conversion efficiency (PCE) compared with that without methanol (19.51% vs 16.53%). Furthermore, the power conversion efficiencies of devices with methanol are still high after kept in dark under ambient environment for 30 days. This work provides a method to prepare high quality perovskite films for planar perovskite solar cells with high performance.

A hierarchical porous carbon nanorods (HPCRs) with highly interconnected three-dimensional conductivity networks derived from metal-organic frameworks have been successfully synthesized via a simple carbonization method. The resultant HPCRs shows an stable porous structure with abundant micro/mesopore on two-dimensional squared shape carbon nanosheets and also between the closely cross-linked carbon sheets. The electrochemical measurements reveal that the HPCRs materials as electrodes for supercapacitor deliver a high specific capacitance of 274 F g−1 at 0.5 A g−1 with an enhanced rate capability in basic media. Moreover, a considerable energy density of 6.77 W h kg−1 at power density of 100 W kg−1 are exhibited for solid-state symmetric supercapacitor. The assembled symmetric supercapacitor also works well under 0 and −20 °C with a remarkable temperature endurance. The large-scale production of unique hierarchical porous carbon nanorods with high efficiency, low cost and one-step synthesis method will be effective electrode materials in energy storage applications.

Hybrid organic/inorganic organometal halide perovskite solar cells (PSCs) have been attracting enormous research interest. However, their performance improvement and engineering at the molecular level remain challenging for the inverted structures. Surface traps present in semiconductor films critically influence ultimate photovoltaic behaviors. A solution-processable and stable cathode buffer layer that can passivate surface traps is thus of great importance for the application of PSCs. Here, we successfully fabricated high performance and stable inverted planar PSCs by employing calcium acetylacetonate (Ca(acac)2), a molecular modulator, as the cathode interfacial layer (CIL). The average power conversion efficiencies of PSCs based on different perovskite photoactive layers were improved. Strikingly, FA0.85MA0.15Pb(I0.85Br0.15)3-based and MAPbI3-based PSC devices were found to have champion power conversion efficiencies of 20.15% and 18.23%, respectively. Importantly, Ca(acac)2-modified PSCs also have high stability. Their power conversion efficiencies decreased by only 15% after 30 days of storage and they show much suppressed hysteresis compared with the control devices (without interfacial modification).

Epidermal growth factor receptor (EGFR) specific therapeutics is of great importance in cancer treatment. Fcy-hEGF fusion protein, composed of yeast cytosine deaminase (Fcy) and human EGF (hEGF), is capable of binding to EGFR and enzymatically convert 5-fluorocytosine (5-FC) to 1000-fold toxic 5-fluorocuracil (5-FU), thereby inhibiting the growth of EGFR-expressing tumor cells. To develop EGFR-specific therapy, 188Re-liposome-Fcy-hEGF was constructed by insertion of Fcy-hEGF fusion protein onto the surface of liposomes encapsulating of 188Re. Western blotting, MALDI-TOF, column size exclusion and flow cytometry were used to confirm the conjugation and bio-activity of 188Re-liposome-Fcy-hEGF. Cell lines with EGFR expression were subjected to treat with 188Re-liposome-Fcy-hEGF/5-FC in the presence of 5-FC. The 188Re-liposome-Fcy-hEGF/5-FC revealed a better cytotoxic effect for cancer cells than the treatment of liposome-Fcy-hEGF/5-FC or 188Re-liposome-Fcy-hEGF alone. The therapeutics has radio- and chemo-toxicity simultaneously and specifically target to EGFR-expression tumor cells, thereby achieving synergistic anticancer activity.

Capitalization is an interpersonal process where one shares personal positive events with others and receives benefits beyond that event's effect. The response a capitalizer perceives from the recipient determines the success of this process. The Perceived Responses to Capitalization Attempts Scale (PRCAS) is an English-language measure used to assess a capitalizer's perception of a recipient's responses. We tested the factor structure, internal consistency reliability, and concurrent validity of the Chinese version of the PRCAS with a sample of 1,213 Chinese college students. Factor analyses replicated the 4-factor model of active–constructive response, passive–constructive response, active–destructive response, and passive–destructive response. All subscales possessed satisfactory internal consistency and evidence for concurrent validity with measures of feeling, flourishing, self-esteem, and mental health symptoms. We also assessed the test–retest stability of the PRCAS with a separate sample of 119 Chinese college students, and found that the subscales possessed low test–retest reliability. Therefore, the Chinese PRCAS possessed acceptable psychometric properties.

Hole transport material free (HTM-free) perovskite solar cells (PSCs) with carbon counter electrode have the advantages of low-cost, good efficiency and high stability. Here in this work, we demonstrate that incorporating Au@SiO2 core-shell NPs into TiO2 scaffold layer increases the power conversion efficiencies (PCEs) of PSCs by improving the light absorption and facilitating carrier transfer or separation through SPR effect. With the optimal concentration of 0.3 wt % Au@SiO2 incorporation, the average PCE of PSCs enhances to 13.85 ± 0.45% from the reference samples of 12.01 ± 0.44%, which is mainly caused by the improved short circuit current density.

Aurivillius-type multiferroic oxides are increasingly being studied for potential application in multifunctional areas because of their feasible platforms incubating photonic, electric, magnetic, etc. properties. Here, we report the original observations of the dielectric relaxation, electromagnetic properties and high-performance microwave absorption of the single-phase Aurivillius-type ceramics. Two thermally activated relaxation processes were determined by the frequency-dependent behaviour of the dielectric loss peak at low and high temperatures. The complex permittivity and permeability were measured at frequencies 2–18 GHz and the microwave attenuation performances were calculated from the experimentally determined electromagnetic parameters. Significantly, the damped dielectric and magnetic resonances were clearly observed at 12–14 GHz and the excellent microwave absorption properties were presented for the first time and are sensitive to the sample thickness. The minimum reflection loss (RL) surpasses − 30 dB at different thicknesses. Especially, the minimum RL reaches − 70.1 dB at 13.2 GHz and the absorption bandwidth (RL≤ −20 dB) is close to 12 GHz (5.7–17.7 GHz). This work opens up a new pathway to develop Aurivillius-type multiferroic oxides in electromagnetic wave attenuation materials.

PEDOT:PSS is one of the most widely used hole transporting layer for inverted perovskite solar cells. Yet the performances of the corresponding perovskite solar cells are not satisfactory. Here, we demonstrate that KCl modified PEDOT:PSS film can promote the crystallization of perovskite film and enlarge the perovskite crystals. At the same time, KCl can diffuse into the perovskite film and effectively passivate the defects. As a result, inverted perovskite solar cells fabricated on 10 mg mL−1 PEDOT:PSS/KCl films exhibit an average power conversion efficiency of 16.24 %, which is enhanced by 17.77 % compared with the reference perovskite solar cells. Open circuit voltage of 1.009 V and power conversion efficiency of 17.09 % have also been demonstrated using the optimized 10 mg mL−1 PEDOT:PSS/KCl films.

Glucagon-like peptide-1 (GLP-1) is a natural incretin hormone released from intestinal L-cells in response to hormonal, neural and nutrient stimuli. Liraglutide is derived from human GLP-1 by substituting Lys34 with Arg and conjugating a palmitic acid to Lys26 via a glutamate spacer, which has a long-lasting hypoglycemic effect. The precursor of liraglutide is a K34R mutant of GLP-1 (GLP-1R34) and was produced previously by either yeast protein expression system or peptide solid phase synthesis. However, degradation of secreted proteins limits the effectiveness of yeast protein expression system and peptide solid phase synthesis requires the use of large amounts of organic solvents and expensive condensation agents. In this study, we reported a novel method to prepare GLP-1R34 using E. coli protein expression system. The GLP-1R34 peptide was overexpressed as an MFH-GLP-1R34 fusion protein and was released from the fusion protein through formic acid cleavage. The target peptide was purified by reverse-phase chromatography and ion exchange chromatography. Our work demonstrated a high-productive process for large-scale preparation of the liraglutide precursor with high purity.

It is a great challenge to prepare high quality perovskite films in ambient atmosphere with high humidity (≥ 50%), since the commonly adopted two step sequential deposition process produces perovskite films with rough surfaces and a large amount of residual PbI 2 . To solve these problems, a facile method using combined solvent and vapor treatment is proposed. The residual PbI 2 is diminished through a solvent treatment process, and then smooth perovskite surface with micrometer scaled perovskite particles is obtained with a CH 3 NH 2 vapor treatment. The quality of the obtained perovskite films is examined in the hole transport material free perovskite solar cells, and power conversion efficiency is boosted up by 17.3% compared with the traditional method. When a CuPc hole transport layer is further introduced, carbon counter electrode based perovskite solar cells exhibit a superior power conversion efficiency of 16.61%. Thus this method shows great potential in further optimizing the performance of perovskite solar cells.

Doping of TiO2 by metal elements for the scaffold layer of the perovskite solar cells has been proved to be one of the effective methods to improve the power conversion efficiency. In the present work, we report the impact of doping of TiO2 nanoparticles with different amounts of tungsten (W) on the photovoltaic properties of hole transport material free perovskite solar cells (PSCs) that employ carbon counter electrode. Light doping with W (less than 1000 ppm) improves the power conversion efficiencies (PCEs) of solar cells by promoting the electron conductivity in the TiO2 layer which facilitates electron transfer and collection. With the incorporation of W, average efficiency of PSCs is increased from 9.1% for the un-doped samples to 10.53% for the 1000 ppm W-doped samples, mainly originates from the increase of short circuit current density and fill factor. Our champion cell exhibits an impressive PCE of 12.06% when using the 1000 ppm W-doped TiO2 films.

Anatase TiO2 ultra-thin nanosheets (TiO2-NS) are synthesized by a facile hydrothermal method. Several merits are realized when employing the prepared TiO2-NS as lithium ion battery anode material, compared to TiO2 nanoparticles. Firstly, the as-prepared TiO2-NS has high charge capacities and a specific surface area up to 98.8 m2g−1, which is beneficial for the insertion of lithium ion. Secondly, the large specific surface area is helpful in enlarging the electrode/electrolyte interfacial area. Finally, the EIS result verifies short electron transfer paths. More importantly, the stability of the nanosheet structure is indirectly confirmed by the excellent cycling performance of charge capacity and the curve of charge capacities versus cycle number at different current densities. After galvanostatic charge/discharge of the batteries for 1000 cycles, the HRTEM images of post-mortem batteries directly reveal a good reversibility of the lithium ion insertion/extraction process aided by TiO2-NS. Thus, all these advantages and the special structure facilitate an excellent cycling performance: the charge capacity with the maximum value of 250 mAh g−1 keeps half after 2000 cycles at a current density of 840 mA g−1 (5 C).

Thiophene/benzene-fused π-conjugated systems are normally employed as the core units of two- and three-dimensionally expanded small molecule hole-transporting materials (HTMs) to improve their electronic and charge transport properties, whereas comparison studies between two-dimensional and three-dimensional core conformations are less reported. To further find useful clues for the design of highly-efficient small molecule HTMs and to find new core units, in this work, four HTM molecules are designed by employing triphenylene, benzotrithiophene, triptycene, and thiophenetriptycene as the core units, and simulated with density functional theory combined with the Marcus hopping model. Our results show that all the considered HTMs display appropriate molecular energy levels, less optical absorption in the visible light region and large Stokes shifts, and high hole mobilities (9.80 × 10−2 cm2 V−1 s−1). Compared with the two-dimensional core structures, the three-dimensional cores exhibit evident superiorities with the same chemical components. Meanwhile, we also find that the quasi-degenerate HOMO energy levels will be helpful to enlarge the transfer integrals between adjacent molecules, and further to promote the hole transport in HTMs. By considering the various elements simultaneously, these investigated HTMs (S-1–S-4) with thiophene- and benzene-fused cores can be expected as potential promising candidates to help create more efficient solar cells.

In recent years, a number of aviation accidents have caused the social attention to aviation safety. The serious shortage of controllers at China's small and medium-sized airports has become an important hidden danger of aviation accidents. It is necessary to make a scientific and reasonable scheduling scheme in order to solve this problem. Based on civil aviation air traffic management rules to the controllers workload, this article proposes a linear programming method to analysis of China's small and medium-sized airport controllers scheduling model. At the same time, the fatigue factor is accounted into and the model is solved by 0-1 integer programming. Using an actual case data from Wanzhou Airport, the proposed mothed satisfies the needs of the airport and reduce controllers work fatigue to achieve a win-win results.

Background miRNAs play crucial role in the progression of K-Ras-mutated nonsmall cell lung cancer (NSCLC). However, most studies have focused on miRNAs that target K-Ras. Here, we investigated miRNAs regulated by mutant K-Ras and their functions. Methods miRNAs regulated by mutant K-Ras were screened using miRNA arrays. miR-199b expression levels were measured by qRT-PCR. The protein expression levels were measured using Western blot and immunohistochemistry. The effects of miR-199b on NSCLC were examined both in vitro and in vivo by overexpressing or inhibiting miR-199b. DNA methylation was measured by bisulfite sequencing. Results An inverse correlation was observed between K-Ras mutation status and miR-199b levels in NSCLC specimens and cell lines. The inhibition of miR-199b stimulated NSCLC growth and metastasis, while restoration of miR-199b suppressed K-Ras mutation-driven lung tumorigenesis as well as K-Ras-mutated NSCLC growth and metastasis. miR-199b inactivated ERK and Akt pathways by targeting K-Ras, KSR2, PIK3R1, Akt1, and Rheb1. Furthermore, we determined that mutant K-Ras inhibits miR-199b expression by increasing miR-199b promoter methylation. Conclusion Our findings suggest that mutant K-Ras plays an oncogenic role through downregulating miR-199b in NSCLC and that overexpression of miR-199b is a novel strategy for the treatment of K-Ras-mutated NSCLC. Electronic supplementary material The online version of this article (10.1186/s13046-019-1170-7) contains supplementary material, which is available to authorized users.

Driven by their ferroelectric, semiconducting, photonic, etc. properties, the potential of Aurivillius-type oxides of binary Bi4Ti3O12-BiFeO3 system in photovoltaic area is increasingly being studied. In this work, Bi5FeTi3O15 (BFTO-4), Bi6Fe2Ti3O18 (BFTO-5) and Bi7Fe3Ti3O21 (BFTO-6) thin films on soda-lime glass, indium tin oxide (ITO) glass, silicon wafer and Pt/Ti/SiO2/Si substrate were prepared by the chemical solution deposition technique. The photovoltaic responses of the substrate/BFTO-4/Au devices measured by adapting “top-top” or “top-bottom” electrodes were observed. All devices present a similar linear dark J-V curve disjointed to zero point and their photovoltaic properties strongly depended on the substrates and electrode connection forms, arising from self-polarization and interface barrier potential. The optimal photovoltaic effect was observed in the BFTO-4 films on Pt/Ti/SiO2/Si substrate without any poling, with the short circuit current (Jsc) of 18.4 μA/cm2 and open circuit voltage (Voc) of 0.14 V under light illumination, which is attributed to larger polarization and c-axis oriented structure. Furthermore, layer effects on photovoltaic properties of the BFTO-4, BFTO-5 and BFTO-6 films deposited on ITO glass were also investigated. With the increase of layers, the devices exhibit an enhancement of Jsc along with the Voc reduction, due to the intrinsic layered structures with different lattice strains. The switching photocurrent behaviors of the BFTO-4 film by typical ON/OFF light measurements verified the stability and reliability of the photovoltaic effect.

The two-step spin coating process produces rough perovskite surfaces in ambient condition with high humidity, which are unfavorable for the contact between the perovskite film and the low temperature carbon electrode. To tackle this problem, multi-walled carbon nanotubes (MWCNTs) are embedded into the perovskite layer. The MWCNTs can act as charge transport high way between individual perovskite nanoparticles and facilitate the collection of the photo-generated holes by the carbon electrode. Longer carrier lifetime is confirmed in the perovskite solar cells with addition of MWCNTs using open circuit voltage decay measurement. Under optimized concentration of MWCNT, average power conversion efficiency of 11.6% is obtained in hole transport material free perovskite solar cells, which is boosted by ∼15% compared to solar cells without MWCNT.

A facile approach to fabricate low-cost hole-transport-material (HTM)-free perovskite solar cell(PSC) based on commercial P25 nanoparticles and bilayer hybrid carbon electrode under ambient condition is reported. The performance of such HTM-free PSCs are highly dependent on the thickness and morphology of the P25 based TiO 2 electron-transport layer(ETL), which can be adjusted by the amount of ethanol and ethyl cellulose in the paste. After optimization, a power conversion efficiency of 12.48% is obtained, which is enhanced by 20.46% compared with solar cells employing hydrothermal TiO 2 ETL. In addition, PSCs with P25 ETL also exhibit excellent long-term stability together with reduced hysteresis. With advantages of low-cost, high efficiency and facile fabrication process, commercial P25 nanoparticles based PSC is highly potential for future commercialization.

Energy and environmental concerns have attracted more and more worldwide attention. As industrialization leads to serious environmental effects on sustainable development, China urgently needs to improve its energy-pollution performance without harming industrial growth. This paper proposes two indexes, the energy-pollution efficiency index and the energy-pollution productivity change index, in a unified framework that not only enables a more comprehensive analysis by simultaneously allowing for both static and dynamic performance evaluations, but also sets a sounder best target environmental effect by jointly considering energy conservation and pollution reduction. This research evaluates the industrial energy-pollution performance of regions in China during the period 1995–2014. Findings reveal that its energy-pollution efficiency was unbalanced and hovered at a low level, showing an urgent need for improvement; however, energy-pollution productivity did gradual increase and technology progress was its main contributor. Energy efficiency was higher than pollution efficiency, and their gap increased instead of narrowing. The east area's energy-pollution efficiency ranked first, while its regional discrepancy presented an increasing trend. Energy-pollution productivity improvement was mainly driven by technology progress, while efficiency change exhibited a negative effect. Finally, energy utilization contributed less to energy-pollution productivity improvement than pollution emissions.

A mesoporous SiO2 layer is successfully introduced into the hole transport material free perovskite solar cells by spin-coating a SiO2 paste onto the TiO2 scaffold layer. This SiO2 layer can act as an insulating layer and effectively inhibit the charge recombination between the TiO2 layer and carbon electrode. The variation of power conversion efficiencies with the thickness of SiO2 layer is studied here. Under optimized SiO2 thickness, perovskite solar cell fabricated on the TiO2/SiO2 film shows a superior power conversion efficiency of ∼12% and exhibits excellent long time stability for 30 days.

The morphology of PbI 2 film plays a critical role in determining the quality of the resultant CH 3 NH 3 PbI 3 film and power conversion efficiency of CH 3 NH 3 PbI 3 perovskite solar cell. Here, we propose a solvent treatment method in the two-step sequential deposition process to control the morphology of PbI 2 film, which leads to enhanced power conversion efficiency. Hole transport material free perovskite solar cell is chosen as a paradigm to demonstrate this idea. Solvent (isopropanol, chlorobenzene, or ethanol) treated PbI 2 films exhibit dendrite-like or flake-like morphologies, which facilitate more complete conversion of PbI 2 to CH 3 NH 3 PbI 3 perovskite in ambient atmosphere with a relative high humidity. Therefore, enhanced performance is obtained with the solvent treated PbI 2 films. Average power conversion efficiency has been improved from 9.42% in the traditional two-step sequential deposition to 11.22% in solar cells derived from ethanol treated PbI 2 films.

We have designed a novel hole-conductor-free and insulation layer free mesoscopic perovskite solar cells (PSCs) with a low cost carbon counter electrode (CE). Significantly, to enhance solar light harvesting capability, a mixture of methylammonium (CH3NH3+, MA) and formamidinium (HNCHNH3+, FA) cations were explored to synthesize superior performance perovskite materials. With the introduction of FAI, Cubic: Column composite structure of (FA)x(MA)1-xPbI3 was formed on the top of mesoscopic TiO2. This nanostructure not only leads to fully coverage of perovskite on TiO2 but also provides salutary electron transport channels to effectively reduce the electron recombination probability. As a result, optimal solar cell efficiency of 13.03% of (FA)x(MA)1-xPbI3 composite structure based PSC (when x is fixed at 0.25) was achieved, while PSC based typical MAPbI3 cuboids only obtained an efficiency of 12.49%. Despite of the improved efficiency, the Cubic: Column composite structure caused by the addition of FAI also contributes to higher long-term and thermal stability.

Multiple degenerate band engineering has been established as an effective approach to maximize electrical transport in thermoelectric materials. A series of polycrystalline samples of chalcopyrite Cu1−x−δAgxInTe2 (x = 0–0.5, δ = 0.02–0.05) was synthesized, to achieve multiple degenerate bands. A pseudocubic structure is realized when x is around 0.2. As a result, the degenerate valence bands influence electrical transport significantly. In addition, the lattice thermal conductivity is significantly depressed in the solid solution due to the strong phonon scattering by strain-field fluctuations, since Ag substitution brings significant anharmonicity to the crystal structure. The highest ZT of 1.24 was obtained at the composition Cu0.75Ag0.2InTe2. This study provides an example how the pseudocubic crystal structure is applied to design and evaluate the TE properties in diamond-like compounds. Introduction to the international collaboration Scientific collaboration between the Shanghai Institute of Ceramics and the Institutes of the Max-Planck Society has a long history. In 2001, the Max-Planck Institute for Chemical Physics of Solids in Dresden and SIC CAS in Shanghai established research cooperation. At the beginning it was focused on the field of solid state chemistry, and later was extended to the studies on thermoelectric materials. Currently this cooperation is intensively realized by the research groups of Prof. Lidong Chen in Shanghai and Prof. Yuri Grin in Dresden. Several publications in journals like Inorganic Chemistry, Dalton Transactions and Chemistry of Materials, as well as numerous presentations in the national and international conferences present the results of the common studies.

Recent progress has shown that low-temperature processed tin oxide (SnO2) is an excellent electron selective layer (ESL) material for fabricating highly efficient organic–inorganic metal-halide perovskite solar cells with a planar cell structure. Low-temperature processing and a planar cell structure are desirable characteristics for large-scale device manufacturing due to their associated low costs and processing simplicity. Here, we report that plasma-enhanced atomic layer deposition (PEALD) is able to lower the deposition temperature of SnO2 ESLs to below 100 °C and still achieve high device performance. With C60-self-assembled monolayer passivation, our PEALD SnO2 ESLs deposited at ∼100 °C led to average power conversion efficiencies higher than 18% (maximum of 19.03%) and 15% (maximum of 16.80%) under reverse voltage scan for solar cells fabricated on glass and flexible polymer substrates, respectively. Our results thus demonstrate the potential of the low-temperature PEALD process of SnO2 ESLs for large-scale manufacturing of efficient perovskite solar cells.

Electrospray laser desorption ionization is an ambient ionization technique that generates neutrals via laser desorption and ionizes those neutrals in an electrospray plume and was utilized to characterize inks in different layers of copy paper and banknotes of various currencies. Depth profiling of inks was performed on overlapping color bands on copy paper by repeatedly scanning the line with a pulsed laser beam operated at a fixed energy. The molecules in the ink on a banknote were desorbed by irradiating the banknote surface with a laser beam operated at different energies, with results indicating that different ions were detected at different depths. The analysis of authentic $US100, $100 RMB and $1000 NTD banknotes indicated that ions detected in ‘color-shifting’ and ‘typography’ regions were significantly different. Additionally, the abundances of some ions dramatically changed with the depth of the aforementioned regions. This approach was used to distinguish authentic $1000 NTD banknotes from counterfeits. Copyright © 2015 John Wiley & Sons, Ltd.

The inverted p-i-n structure perovskite solar cells show great potential in wearable devices and flexible solar cells. Yet the commonly used PEDOT:PSS hole transporting layer still needs to be optimized in order to pursue superior performances. Here, we have demonstrated that PEDOT:PSS/GQDs composite film can be a potential alternative to replace the PEDOT:PSS. Under optimized conditions, average power conversion efficiencies are boosted from 12.77% for perovskite solar cells fabricated on PEDOT:PSS film to 15.24% for perovskite solar cells fabricated on PEDOT:PSS/GQDs film. A champion power conversion efficiency of 16.15% has also been demonstrated with the optimized PEDOT:PSS/GQDs composite film.

Introducing a solution processed hole transporting layer into the low temperature paintable carbon electrode based perovskite solar cells is highly desirable to further enhance their power conversion efficiencies. At the same time, this low cost method is compatible with roll-to-roll mass production. Here, we have demonstrated that Cu2ZnSnS4 (CZTS) nanoparticles can be a potential hole transporting layer for low temperature paintable carbon electrode based perovskite solar cells. Under optimized conditions, perovskite solar cells with a CZTS hole transporting layer exhibit an average power conversion efficiency of 12.53%, which is enhanced by ~50% compared with perovskite solar cell without a CZTS hole transporting layer. At the same time, perovskite solar cells with CZTS hole transporting layer demonstrate negligible hysteresis and excellent long time stability.

Nanoporous submicron TiO2 spheres of diameters around 200 nm are synthesized by a hydrothermal process and used as a scaffold layer for improving light absorption, charge transportation, as well as photovoltaic performance in hole-transport-layer free perovskite solar cells employing carbon counter electrodes. The TiO2 submicron spheres show a porous feature with high specific surface area, which is essential for perovskite infiltration, charge extraction, and transportation in mesoscopic perovskite solar cells. Furthermore, big spheres exhibit better light scattering property compared to traditional TiO2 nanoparticles, thus enhancing light absorption in corresponding devices. The present perovskite solar cells employ a TiO2 scaffold layer of optimized thickness of about 600 nm and show an average power conversion efficiency of 13.46 ± 0.41%, which is 18.4% higher than that of counterparts based on TiO2 nanoparticle (11.37 ± 0.40%). The champion cell exhibits an impressive efficiency of 14.3%, which is ve...

Liquid electrolytes employing fluorescent perylene are prepared and applied in dye sensitized solar cells (DSSCs). Due to the excellent down-shifting property of perylene, photons with short wavelength (from about 350 to 440 nm) can be absorbed and then converted to ones with longer wavelength (from 450 nm to 550 nm) which can be more efficiently utilized by DSSCs. As a result, device with optimal concentration of 0.05 M perylene presents an efficient improvement in the short-circuit current density ( J sc ), leading to an increase of 11.6% in the power conversion efficiency (PCE) compared with the reference DSSC based on control electrolyte.