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Cu2ZnSnS4 (CZTS) nanocrystals were synthesized by a hot injection method. Ultraviolet (UV) Raman spectroscopy measurements showed that ZnS impurities existed in CZTS with a Zn/Sn precursor ratio of 1.2. Combining Raman spectra with energy-dispersive X-ray spectroscopy (EDS) characterization, the formation mechanism of CZTS and ZnS impurities were also investigated. We found that crystalline CZTS and Cu2SnS3, as well as amorphous ZnS, formed after sulfur-oleylamine was injected into the mixture solution. Amorphous ZnS reacted with Cu2SnS3 to form CZTS during sulfur annealing at high temperature. However, if the Zn/Sn ratio was too high, the excess ZnS could not be eliminated even after a longer reaction time. A relatively pure phase of CZTS was only obtained by decreasing the Zn/Sn precursor ratio to 0.6. Moreover, CZTS nanocrystals were assembled into thin films by electrophoretic deposition onto molybdenum-coated soda lime glass and the photoelectrochemical properties of CZTS photocathodes with and without ZnS impurities were investigated. A CZTS photocathode without ZnS demonstrated higher photocurrent than those with ZnS. The results will deepen the understanding of the CZTS formation process and be helpful to explore efficient CZTS solar conversion devices. [ABSTRACT FROM AUTHOR]

The surface treatment of In0.30Ga0.70N photoelectrode in different acid electrolytes (HCl, HBr and a H2SO4 aqueous solution) has been investigated. The highest photocurrent is obtained after the surface treatment in H2SO4 aqueous solution. After H2SO4 treatment, the In0.30Ga0.70N photoelectrode responds to 550 nm and the maximum incident photon-to-current efficiency reaches about 58% under 400-430 nm, which is higher than the previous highest value (42%) on an InGaN photoelectrode. A possible mechanism is also proposed to explain the reason for the highest photocurrent enhancement after H2SO4 surface treatment. The results of the x-ray photoelectron spectroscopy, the inductively coupled atomic emission spectroscope and the electrochemical impedance spectra suggest that the surface segregation layer, as recombination centres of photo-generated holes and electrons, is decreased after H2SO4 surface treatment. [ABSTRACT FROM AUTHOR]

Cu2ZnSnS4 (CZTS) films were prepared by ultrasonic spray pyrolysis on FTO (SnO2 : F on glass) substrates. The effect of substrate temperatures on the phases, morphologies and photoelectrochemical properties of CZTS films was investigated. X-ray diffraction, Raman spectrum and energy-dispersive spectrometry were used to confirm the phases of the CZTS films. The samples at 400 and 450 ?C exhibited a higher photocurrent than the samples at 350 and 500 ?C. Moreover, the band positions of CZTS were measured by a facile Mott-Schottky method for the first time. Different from the previous calculation and experimental data, the conduction band position of CZTS was 0.26 eV higher than that of CdS. The results can explain well the low open circuit voltage of a CZTS-based solar cell and offer guidance to improving CZTS solar cells. [ABSTRACT FROM AUTHOR]

Nano-leaf bismuth vanadate (BiVO4), which acts as an active photocatalyst for O2evolution under visible light irradiation, was synthesized by a wet chemical method. The BiVO4photocatalyst was obtained by the reaction of Bi(NO3)3·5H2O and NH4VO3at a low temperature (60 °C). Both the morphology and the crystal phase of the synthesized product can be tuned by changing the concentrations of the precursor. The O2evolution activity of BiVO4nano-leaves from photocatalytic water splitting under visible light irradiation ( λ>420 nm) is significantly higher than that of the BiVO4sample synthesized by a traditional solid state reaction method, and the activity can be further improved by annealing the samples. [ABSTRACT FROM AUTHOR]

The search for active semiconductor photocatalysts that directly split water under visible-light irradiation remains one of the most challenging tasks for solar-energy utilization. Over the past 30 years, the search for such materials has focused mainly on metal-ion substitution as in In1−xNixTaO4 and (V-,Fe- or Mn-)TiO2 (refs 7,8), non-metal-ion substitution as in TiO2−xNx and Sm2Ti2O5S2 (refs 9,10) or solid-solution fabrication as in (Ga1−xZnx)(N1−xOx) and ZnS–CuInS2–AgInS2 (refs 11,12). Here we report a new use of Ag3PO4 semiconductor, which can harness visible light to oxidize water as well as decompose organic contaminants in aqueous solution. This suggests its potential as a photofunctional material for both water splitting and waste-water cleaning. More generally, it suggests the incorporation of p block elements and alkali or alkaline earth ions into a simple oxide of narrow bandgap as a strategy to design new photoelectrodes or photocatalysts. [ABSTRACT FROM AUTHOR]

N-doped SrTiO3and (SrTiO3)1−x·(LaTiO2N)xsamples were prepared by the thermal ammonolysis method. The photocatalytic activities of the samples were investigated in a water suspension system. Aqueous methanol solution (50 mL CH3OH + 220 mL H2O) for H2evolution and aqueous silver nitrate solution (270 mL, 0.01 mol L−1) for O2evolution were used as sacrificial reagents. The oxynitrides showed photocatalytic activities under visible light irradiation. The maximum rates of photocatalytic hydrogen and oxygen evolution under visible light irradiation (λ> 420 nm) were 10 and 8 μmol h−1, respectively. The samples were characterized by X-ray diffractometry, UV-Vis spectrophotometry, Fourier transform infrared spectrometry, and laser Raman spectroscopy. The unit cell edge length of (SrTiO3)1−x·(LaTiO2N)xincreased linearly and their band gaps reduced from 3.18 to 2.04 eV with increasing xfrom 0 to 0.30. Moreover, the calculation results of (SrTiO3)0.75·(LaTiO2N)0.25by density functional theory suggested that the band gap narrowing of the solid solutions came from the hybridization of N2pand O2porbital. The band positions of the solid solutions were further investigated by Mott-Schottky and the onset potential method. The results suggested that the conduction band of the solid solution was lowered, which led to decrement of the hydrogen evolution rate. [ABSTRACT FROM AUTHOR]

N-type semiconductor thin films of WO3, Fe2O3and the composite structure of WO3/Fe2O3were prepared on FTO (SnO2?:?F on glass) substrates by the sol-gel method. Their structures and optical properties were characterized by XRD, SEM and UV-Vis spectrometry. Their photoelectrochemical properties were also investigated in a three-electrode cell system. The results showed that the photocurrent of the WO3/Fe2O3film was higher than that of WO3or Fe2O3alone, particularly under visible light illumination (? > 440?nm). In this case there was almost no photocurrent in the WO3film. A reasonable explanation was that the photo-generated electrons could transfer more easily in WO3/Fe2O3than in WO3or Fe2O3alone due to their special conduction band structures. Therefore, the interface between WO3and Fe2O3played an important role in improving the conversion efficiency. [ABSTRACT FROM AUTHOR]

We studied photoelectrochemical performance of the undoped, Si-doped, Ti-doped, and codoped α-Fe2O3 film prepared by ultrasonic spray pyrolysis. Since the ions radius of Si4+3+4+, Si and Ti codoping can balance the ion radius difference between Fe3+ and Si4+ (or Ti4+) and increase the donor concentration. Their donor concentrations, calculated from slopes of the Mott–Schottky plots, are 9.10×1018 cm-3, 1.89×1020 cm-3, 2.04×1020 cm-3, and 7.06×1020 cm-3, respectively. Incident photon to current efficiency of the codoped film is 34% at 365 nm and 0.6 V versus Ag/AgCl, much higher than 10%, 20%, and 22% for the undoped, Si-doped, and Ti-doped film, respectively. [ABSTRACT FROM AUTHOR]

Hole transporting layers are very important for solar energy conversion devices, such as perovskite solar cells, organic photovoltaic devices and solar water splitting cells. Recently, CuGaO2 as a hole transporting layer has attracted intense interest due to its high hole mobility and wide band gap. However, there is still a challenge to prepare a semitransparent CuGaO2 film. It is desirable to develop a facile method to prepare a CuGaO2 film with good electronic contact and semi-transparency for application in solar energy conversion devices. Herein, for the first time, a one-step hydrothermal method is developed to directly grow semi-transparency p-CuGaO2 films on FTO substrates. CuGaO2 single crystals with much larger grain sizes are obtained, which are important for the applications as hole transporting layers. We find that Br− in the precursor solution plays a key role in obtaining a semitransparent CuGaO2 film. The effects of Br− on the growth of CuGaO2 are also investigated in details. As an example, a CuGaO2 film is used as a hole transfer layer to improve photoelectrochemical performance of a CuInS2 photocathode for solar water splitting. [ABSTRACT FROM AUTHOR]

P-type Cu(In,Ga)S2 semiconductors are promising candidates to be used as photocathodes for solar water splitting. Porous structures have been widely used to improve the performances of photoelectrodes due to good minority carrier transport. However, a porous photoelectrode has longer transport distance of majority carriers, which limits its performance. Controlling pore volume of a photoelectrode can balance minority and majority carrier transport and improve the performance. Here, a porous Cu(In,Ga)S2 film is prepared by facile spin-coating method. The pore volume of Cu(In,Ga)S2 film is controlled by adjusting relative humidity (RH) of air during spin-coating process. Further studies suggest that polyvinyl acetate (PVAc) in precursor solution is a humidity sensitive polymer and plays a key role to form different pore volume. The 40% RH sample has the best performance due to its optimum pore volume. After further coated with CdS surface passivation layer and Pt electrocatalyst on the surface, a 40% RH Cu(In,Ga)S2 photocathode indicates a photocurrent density of 8.6 mA cm−2 at 0 VRHE, which is one of the highest photocurrents of Cu(In,Ga)S2 photocathodes. This new strategy for adjusting pore volume is also suitable to prepare other solution-processed inorganic materials. [ABSTRACT FROM AUTHOR]

Hematite (α-Fe2O3) is a promising photoanode material for solar water splitting due to its suitable band gap, earth-abundance, excellent stability and non-toxicity. However, a short hole diffusion length limits its performance. A nanorod array structure can shorten hole transfer distance to photoelectrode/electrolyte interface and decrease recombination of photo-generated carriers. However, average diameters of all previously reported nanorods are over 50 nm, thus being too thick for holes to transfer to the interface. It is still a big challenge to prepare a Fe2O3 nanorod array photoelectrode with finer diameter. In this study, we prepare an ultrafine α-Fe2O3 nanorod array film with average diameter about 25 nm by calcining γ-FeOOH for the first time. The ultrafine nanorod array photoanode indicates much higher carrier separation efficiency and performance than a conventional nanorod array film. [ABSTRACT FROM AUTHOR]

Cu2ZnSnS4 (CZTS) is one of the most promising light capture materials for solar cells or solar fuels. Construction of 3D hierarchical structure is very important for efficient optoelectronic devices. It is challenging to directly fabricate 3D hierarchical structure CZTS film by a facile solution method. Herein, we present a one-step sol–gel method for fabrication of CZTS thin films with 3D hierarchical structures. For the first time, it is found that the morphologies of thin films can be adjusted between dense, porous and 3D hierarchical structures by tuning anion ratios of Cl−/Ac− in precursor solution. Further analysis suggests the formation of intermediate phases of SnO2 nanoparticles and SnS2 nanosheets by tuning ratios of Cl−/Ac− in precursor solution, which has important effects on the formation of different nanostructures of CZTS. This study can deepen understanding of anion’ effect on morphologies of samples using a solution method and forms a reference to prepare novel nanostructures of other materials. [ABSTRACT FROM AUTHOR]

BiVO4 films were deposited on fluorine-doped tin oxide substrates by chemical bath deposition. The samples were characterized by an x-ray diffractometer, UV-Vis transmission spectra and a scanning electron microscope. The morphologies of the samples were adjusted by the deposition time, temperature, pH of solution and buffer solution. When the temperature and pH value of the solution were high, the polyhedron microcrystal of BiVO4 exposed fewer less planes on the surface and the films were more compact. On the basis of the experimental results, a possible growth mechanism was proposed. Moreover, the photoelectrochemical properties of the samples with different morphologies were investigated. The results suggested that the compact films with a smaller microcrystal exhibited better performance, which was helpful to understand the relationship between the morphologies of other microcrystal electrodes and their photoelectrochemical properties. [ABSTRACT FROM AUTHOR]

Abnormal alternative splicing (AS) caused by alterations to splicing factors contributes to tumor progression. Serine/arginine splicing factor 1 (SRSF1) has emerged as a key oncodriver in numerous solid tumors, leaving its roles and mechanisms largely obscure in glioma. Here, we demonstrate that SRSF1 is increased in glioma tissues and cell lines. Moreover, its expression was correlated positively with tumor grade and Ki-67 index, but inversely with patient survival. Using RNA-Seq, we comprehensively screened and identified multiple SRSF1-affected AS events. Motif analysis revealed a position-dependent modulation of AS by SRSF1 in glioma. Functionally, we verified that SRSF1 promoted cell proliferation, survival, and invasion by specifically switching the AS of the myosin IB (MYO1B) gene and facilitating the expression of the oncogenic and membrane-localized isoform, MYO1B-fl. Strikingly, MYO1B splicing was dysregulated in parallel with SRSF1 expression in gliomas and predicted the poor prognosis of the patients. Further investigation revealed that SRSF1-guided AS of the MYO1B gene increased the tumorigenic potential of glioma cells through the PDK1/AKT and PAK/LIMK pathways. Taken together, we identify SRSF1 as an important oncodriver that integrates AS control of MYO1B into promotion of gliomagenesis and represents a potential prognostic biomarker and target for glioma therapy. [ABSTRACT FROM AUTHOR]

Double-lumen intubation under general anesthesia is currently the most commonly performed intubation technique for pneumonectomy, wedge resection of the lung, and lobectomy. However, there is a high incidence of pulmonary complications arising from general anesthesia with tracheal intubation. Non-intubation with the preservation of voluntary breathing is an alternative to anesthesia. Non-intubation procedures minimize the adverse effects of tracheal intubation and general anesthesia, such as intubation-related airway trauma, ventilation-induced lung injury, residual neuromuscular blockade, and post-operative nausea and vomiting. However, the steps for non-intubation procedures are not detailed in many studies. Here, we present a concise non-intubated protocol for the performance of video-assisted thoracoscopic surgery with preserved autonomic breathing. This article identifies the conditions necessary to convert from non-intubated to intubated anesthesia and also discusses the advantages and limitations of non-intubated anesthesia. In this work, this intervention was performed on 58 patients. In addition, the results of a retrospective study are presented. Compared with intubated general anesthesia, patients in the non-intubated video-assisted thoracic surgery group had lower rates of post-operative pulmonary complications, shorter operative times, less intraoperative blood loss, shorter PACU stays, a lower number of days to chest drain removal, less post-operative drainage, and shorter hospital stays.