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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%.

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.

Rice planthoppers and associated virus diseases have become the most important pests threatening food security in China and other Asian countries, incurring costs of hundreds of millions of US dollars annually in rice losses, and in expensive, environmentally harmful, and often futile control efforts. The most economically damaging species, the brown planthopper, Nilaparvata lugens (Hemiptera: Delphacidae), cannot overwinter in temperate East Asia, and infestations there are initiated by several waves of windborne spring or summer migrants originating from tropical areas in Indochina. The interaction of these waves of migrants and synoptic weather patterns, driven by the semi-permanent western Pacific subtropical high-pressure (WPSH) system, is of critical importance in forecasting the timing and intensity of immigration events and determining the seriousness of subsequent planthopper build-up in the rice crop. We analysed a 26-year data set from a standardised light trap network in Southern China, showing that planthopper aerial transport and concentration processes are associated with the characteristics (strength and position) of the WPSH in the year concerned. Then, using N. lugens abundance in source areas and indices of WPSH intensity or related sea surface temperature anomalies, we developed a model to predict planthopper numbers immigrating into the key rice-growing area of the Lower Yangtze Valley. We also demonstrate that these WPSH-related climatic indices combined with early-season planthopper catches can be used to forecast, several months in advance, the severity of that season’s N. lugens infestations (the correlation between model predictions and outcomes was 0.59), thus allowing time for effective control measures to be implemented. Electronic supplementary material The online version of this article (10.1007/s10340-018-1022-9) contains supplementary material, which is available to authorized users.

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.