Exploring the Effects of Crystal Facet Orientation at the Heterojunction Interface on Charge Separation for Photoanodes.

As one of the most effective strategies to promote the spatial separation of charges, constructing heterojunction has received extensive attention in recent years. However, it remains unclear whether the crystal facet orientation (CFO) at the heterojunction interface is contributory to charge separation. Herein, three types of TiO2/CdS heterojunction films with different CFOs at the heterojunction interface were produced by adjusting the CdS CFO through in situ conversion. Among them, the TiO2/CdS film with a mixed CdS CFO showed the maximum photocurrent density and charge separation efficiency. In contrast, the TiO2/CdS film with a uniform CdS (100) (CdS-100) performed worst. According to the results of experimentation and DFT calculation, these three types of TiO2/CdS films varied significantly in electron transport time. This is attributable to the different Fermi levels of CdS CFO and the formation of different built-in electric fields upon coupling with TiO2. The rise in the Fermi level of CdS can increase the driving force required for charge migration at the heterojunction interface. Additionally, a stronger built-in electric field is conducive to charge separation. To sum up, these results highlight the significant impact of CFO at the heterojunction interface on charge separation.

Nanoetching TiO2 nanorod photoanodes to induce high-energy facet exposure for enhanced photoelectrochemical performance.

Crystal facet engineering is considered as an effective way to improve photoelectrochemical (PEC) performance. Here, we have developed a nanoetching technology (TiO2 → TiO2/Bi4Ti3O12 → TiO2/BiVO4 → etching-TiO2) to treat rutile TiO2 nanorod films. Interestingly, the technology can induce the exposure of a large number of high energy (101) faces, and the etching-TiO2 film (E-TiO2) showed a significantly enhanced PEC performance. A dynamic study indicates that charge separation and transfer have been obviously improved by such a nanoetching technology. In particular, the charge transfer efficiency (ηtrans) of E-TiO2 reaches 93.4% at 1.23 V vs. RHE without any loaded cocatalyst. The mechanism of PEC performance enhanced by the strategy is experimentally and theoretically unraveled. The improvement of PEC performance is mainly attributed to the shorter distance between H and the neighboring O-b for the HO* intermediates of the rutile (101) facet, which can reduce the energy barrier for the OER. Besides, the driving force for spatial charge separation between the (110) and (101) facets can promote charge separation. This work offers a new and versatile nanotechnology to induce the exposure of the high energy crystal facets and improve the PEC performance.

Association Between Ischemic Stroke and Left Atrial Appendage Morphology in Patients With Atrial Fibrillation and Low CHA2DS2-VASc Scores.

BACKGROUND: Patients with atrial fibrillation are at risk for ischemic stroke, even with low CHA2DS2-VASc scores. The left atrial appendage is a known site of thrombus formation in individuals with atrial fibrillation. METHODS: We conducted a prospective study, enrolling patients with nonvalvular atrial fibrillation and CHA2DS2-VASc scores of 0 or 1. Patients were divided into groups based on left atrial appendage morphology (determined by computed tomography): the "chicken wing" group and the non-chicken wing group. We followed patients for more than 1 year to observe the incidence of stroke. RESULTS: Of 509 patients with a mean (SD) age of 48.9 (11.6) years; 332 (65.2%) were men. The chicken wing group had fewer left atrial appendage lobes, a lower left atrial appendage depth, and a smaller left atrial appendage orifice area (all P < .001). During the follow-up period, 5 of the 133 patients (3.8%) in the chicken wing group and 56 of the 376 patients (14.9%) in the non-chicken wing group experienced ischemic stroke (P < .001). The following findings were significantly associated with the incidence of stroke: left atrial appendage depth (hazard ratio [HR], 1.98; 95% CI, 1.67-3.12; P = .03), left atrial appendage orifice area (HR, 2.16; 95% CI, 1.59-3.13; P < .001), and non-chicken wing left atrial appendage morphology (HR, 1.16; 95% CI, 1.10-1.23; P < .001). CONCLUSION: For patients with atrial fibrillation and a low CHA2DS2-VASc score, the non-chicken wing left atrial appendage morphology type is independently associated with ischemic stroke.

LncRNA HCG18 promotes osteosarcoma growth by enhanced aerobic glycolysis via the miR-365a-3p/PGK1 axis.

BACKGROUND: Osteosarcoma (OS) is a common primary bone malignancy. Long noncoding RNA HCG18 is known to play an important role in a variety of cancers. However, its role in OS and relevant molecular mechanisms are unclear. METHODS: Real-time quantitative PCR was performed to determine the expression of target genes. Function experiments showed the effects of HCG18 and miR-365a-3p on OS cell growth. RESULTS: HCG18 expression was increased in OS cell lines. Moreover, in vitro and in vivo experiments demonstrated that HCG18 knockdown inhibited OS cell proliferation. Mechanistically, HCG18 was defined as a competing endogenous RNA by sponging miR-365a-3p, thus elevating phosphoglycerate kinase 1 (PGK1) expression by directly targeting its 3'UTR to increase aerobic glycolysis. CONCLUSION: HCG18 promoted OS cell proliferation via enhancing aerobic glycolysis by regulating the miR-365a-3p/PGK1 axis. Therefore, HCG18 may be a potential target for OS treatment.

Activating a TiO2/BiVO4 Film for Photoelectrochemical Water Splitting by Constructing a Heterojunction Interface with a Uniform Crystal Plane Orientation.

The construction of a heterojunction has been considered one of the most effective strategies to improve the photoelectrochemical (PEC) performance of photoanodes; however, most researchers only focus on the design and preparation of a novel and efficient heterojunction photoelectrode, and the investigation on the effect of the heterojunction interface structure on PEC performance is ignored. In this work, a TiO2/BiVO4 photoanode with a uniform crystal plane orientation in the heterojunction interface (TiO2-110/BiVO4-202) was prepared by an in situ transformation method. We found that the PEC activity of the TiO2/BiVO4 photoanode can be activated by constructing such a heterojunction interface. Compared with a TiO2/BiVO4 photoanode with a random crystal plane orientation prepared by a simple soaking-calcining method (S-TiO2/BiVO4, 0.04 mA/cm2 at 1.23 VRHE), the TiO2/BiVO4 photoanode prepared by the in situ transformation method (I-TiO2/BiVO4) exhibits a significantly better PEC performance, and the photocurrent density of I-TiO2/BiVO4 is about 2.2 mA/cm2 at 1.23 VRHE under visible light irradiation without a cocatalyst. This is mainly attributed to the fact that I-TiO2/BiVO4 has a faster electron transfer rate in the heterojunction interface according to the results of PEC analysis. Furthermore, density functional theory (DFT) calculations show that the BiVO4-202 surface has a higher Fermi energy level, thereby expediting the photogenerated carrier transport in the heterojunction interface. This work corroborates and strengthens the view that the heterojunction interface structure has a significant effect on the PEC performance.

Analysis of Serum Interleukin-37 Level and Prognosis in Patients with ACS.

OBJECTIVE: To explore the level of serum interleukin-37 in patients with acute coronary syndrome (ACS) and its prognostic value. METHODS: Altogether, 121 continuous ACS cases from September 2017 to June 2020 were selected as the research group (RG), and 107 healthy individuals during the same period were obtained as the control group (CG). ELISA was applied to test IL-37 in the serum of the CG and the RG. Chemiluminescence immunoassay was applied to test NT-pro BNP and hs-cTnI in each group and immune scattering turbidimetry to test hs-CRP. The correlation of IL-37 with serum NT-pro BNP, hs-cTnI, and CRP was analyzed, and the value of IL-37 in diagnosis and prognosis prediction of patients with ACS was tested. Logistic regression was applied to test the independent risk factors affecting poor prognosis of patients with ACS. RESULTS: IL-37 was poorly expressed in patients with ACS, which had a high diagnostic value for ACS (sensitivity: 94.39%, specificity: 74.38%, and area under curve: 0.945). There was a negative correlation of IL-37 with serum NT-pro BNP, hs-cTnI, and CRP. IL-37 in patients with poor prognosis was markedly declined compared with that of patients with good prognosis, and the predicted AUC was 0.965. Logistic regression revealed that low IL-37, diabetes, high CRP, NT-pro BNP, and hs-cTnI in the blood were independent risk factors for poor prognosis in patients with ACS. CONCLUSION: IL-37 is low expressed in patients with ACS, which has a good diagnostic and prognostic value for ACS, and may be applied as an important marker for the prediction of patients with ACS.

Photodegradation of Cationic and Anioic Dyes by pH-Dependent Dispersion of Amphoteric g-C3N4 Nanosheets.

g-C3N4 nanosheets (NSs) were prepared via H2SO4 exfoliation from the bulky g-C3N4 and the photocatalytic (PC) activities were investigated comprehensively using Rodamine B (RhB) and Chromotrope 2R (Ch2R) as candidate pollutants. The results showed that the pH value have important functions in the improvement of photodegradation performance of C3N4 NSs. RhB as cationic dye could be photodegraded more efficiently under acidic conditions while Ch2R as anionic dye was degraded easily in pH ≥ 11 solution. In particular, the Ch2R could be degraded completely within only 30 min in pH = 11 solution. It might be because the amphoteric C3N4 NSs surface with carboxyl and amino groups possessed negative and positive charges in alkaline and acidic conditions, respectively. These results presumably provided a new idea to enhance the pH-dependent photodegradation activity and degrade different types of pollutants selectively by adjusting the pH of amphoteric nanocatalyts.

Ratiometric dual fluorescence tridurylboron thermometers with tunable measurement ranges and colors.

Noncontact ratiometric fluorescent thermometers have received great interests in recent years. Besides being a sensitive and easily observable detection signal, the ratiometric dual fluorescence are also highly accurate and resistable to interference. However, organic molecular thermometers with such fluorescence property are very rare, and their measurement ranges and colors are limited. In this work, a series of ratiometric dual fluorescent tridurylboron thermometers, with tunable measurement ranges and colors, are designed and synthesized. The measurement ranges of the thermometers are -20 °C-40 °C, -10 °C-50 °C and -25 °C-30 °C in solid polymeric systems, and -50 °C-100 °C and -30 °C-110 °C in liquid organic solvent. With decreasing temperature, the fluorescence colors of tridurylboron-MOE thermometers are from green yellow to yellow red, green to green yellow, blue to green. This study provides a novel strategy for developing tunable ratiometric dual fluoresence organic molecular thermometers.

Phase transformation synthesis of TiO2/CdS heterojunction film with high visible-light photoelectrochemical activity.

CdS/TiO2 heterojunction film used as a photoanode has attracted much attention in the past few years due to its good visible light photocatalytic activity. However, CdS/TiO2 films prepared by conventional methods (successive ionic layer adsorption and reaction, chemical bath deposition and electrodeposition) show numerous grain boundaries in the CdS layer and an imperfect contact at the heterojunction interface. In this study, we designed a phase transformation method to fabricate CdS/TiO2 nanorod heterojunction films. The characterization results showed that the CdS layer with fewer grain boundaries was conformally coated on the TiO2 nanorod surface and the formation mechanism has been explained in this manuscript. Moreover, the prepared CdS/TiO2 films show a high photocatalytic activity and the photocurrent density is as high as 9.65 mA cm-2 at 0.80 V versus RHE. It may be attributed to fewer grain boundaries and a compact heterojunction contact, which can effectively improve charge separation and transportation.

Efficient Planar Perovskite Solar Cells with Reduced Hysteresis and Enhanced Open Circuit Voltage by Using PW12-TiO2 as Electron Transport Layer.

An electron transport layer is essential for effective operation of planar perovskite solar cells. In this Article, PW12-TiO2 composite was used as the electron transport layer for the planar perovskite solar cell in the device structure of fluorine-doped tin oxide (FTO)-glass/PW12-TiO2/perovskite/spiro-OMeTAD/Au. A proper downward shift of the conduction band minimum (CBM) enhanced electron extraction from the perovskite layer to the PW12-TiO2 composite layer. Consequently, the common hysteresis effect in TiO2-based planar perovskite solar cells was significantly reduced and the open circuit voltage was greatly increased to about 1.1 V. Perovskite solar cells using the PW12-TiO2 compact layer showed an efficiency of 15.45%. This work can contribute to the studies on the electron transport layer and interface engineering for the further development of perovskite solar cells.

In situ synthesis of Bi2S3 sensitized WO3 nanoplate arrays with less interfacial defects and enhanced photoelectrochemical performance.

In this study, Bi2S3 sensitive layer has been grown on the surface of WO3 nanoplate arrays via an in situ approach. The characterization of samples were carried out using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and ultraviolet-visible absorption spectroscopy (UV-vis). The results show that the Bi2S3 layer is uniformly formed on the surface of WO3 nanoplates and less interfacial defects were observed in the interface between the Bi2S3 and WO3. More importantly, the Bi2S3/WO3 films as photoanodes for photoelectrochemical (PEC) cells display the enhanced PEC performance compared with the Bi2S3/WO3 films prepared by a sequential ionic layer adsorption reaction (SILAR) method. In order to understand the reason for the enhanced PEC properties, the electron transport properties of the photoelectrodes were studied by using the transient photocurrent spectroscopy and intensity modulated photocurrent spectroscopy (IMPS). The Bi2S3/WO3 films prepared via an in situ approach have a greater transient time constant and higher electron transit rate. This is most likely due to less interfacial defects for the Bi2S3/WO3 films prepared via an in situ approach, resulting in a lower resistance and faster carrier transport in the interface between WO3 and Bi2S3.

Highly Efficient Photoelectrochemical Hydrogen Generation Using Zn(x)Bi2S(3+x) Sensitized Platelike WO3 Photoelectrodes.

Zn(x)Bi2S(3+x) sensitized platelike WO3 photoelectrodes on FTO substrates were for the first time prepared via a sequential ionic layer adsorption reaction (SILAR) process. The samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet visible spectrometry (UV-vis), and Raman spectra. The results show that the ZnxBi2S3+x quantum dots (QDs) are uniformly coated on the entire surface of WO3 plates, forming a WO3/Zn(x)Bi2S(3+x) core/shell structure. The Zn(x)Bi2S(3+x)/WO3 films show a superior ability to capture visible light. High-efficiency photoelectrochemical (PEC) hydrogen generation is demonstrated using the prepared electrodes as photoanodes in a typical three-electrode electrochemical cell. Compared to the Bi2S3/WO3 photoelectrodes, the Zn(x)Bi2S(3+x)/WO3 photoelectrodes exhibit good photostability and excellent PEC activity, and the photocurrent density is up to 7.0 mA cm(-2) at -0.1 V versus Ag/AgCl under visible light illumination. Investigation of the electron transport properties of the photoelectrodes shows that the introduction of ZnS enhances the photoelectrons' transport rate in the photoelectrode. The high PEC activity demonstrates the potential of the Zn(x)Bi2S(3+x)/WO3 film as an efficient photoelectrode for hydrogen generation.