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1.
Front Neurol ; 14: 1240150, 2023.
Article in English | MEDLINE | ID: mdl-37965171

ABSTRACT

The incidence of gliomas is approximately 3-5/100,000, with high-grade gliomas accounting for approximately 30-40% of these tumors. Surgery is a confirmed positive factor in prolonging the survival of these patients, and a larger resection range means a longer survival time. Therefore, surgery for high-grade glioma patients should aim to maximize the extent of resection while preserving neurological function to achieve a better quality of life. There is consensus regarding the need to lengthen progression-free survival (PFS) and overall survival (OS) times. In glioma surgery, methods such as intraoperative computed tomography (ICT), intraoperative magnetic resonance imaging (IMRI), navigation, 5-aminolevulinic acid (5-ALA), and intraoperative ultrasound (IOUS) are used to achieve an expanded resection during the surgical procedure. IOUS has been increasingly used in the surgery of high-grade gliomas and various tumors due to its convenient intraoperative use, its flexible repeatability, and the relatively low cost of operating room construction. With the continuous upgrading of ultrasound equipment, IOUS has been able to better assist surgeons in achieving an increased extent of resection. This review aims to summarize the application of ultrasound in the surgery of high-grade gliomas in the past decade, its improvement in patient prognosis, and its prospects.

2.
Materials (Basel) ; 16(19)2023 Sep 22.
Article in English | MEDLINE | ID: mdl-37834485

ABSTRACT

Microbially induced carbonate precipitation (MICP) technology holds great potential in enhancing soil properties. MICP can be employed to enhance the stability and strength of diverse sandy soil, but it has the shortcoming of low curing efficiency. In response to the identified problem, this study aims to investigate an optimized treatment protocol that involves formulating a cementing solution in a hydrochloric acid (HCl) solution to enhance the solidification rate in the MICP reaction and evaluate its effectiveness. The results indicate that when preparing a 1 M cementing solution in a 0.2 M HCl solution, it promotes the rapid bonding of calcareous sand particles, resulting in an unconfined compressive strength (UCS) of 1312.6 kPa in the sand column after five treatments. Compared to the conventional test group, the experimental group containing HCl exhibited an approximately 1357% increase in UCS. The analysis unveiled the pivotal role of metal ions dissolved from calcareous sand by HCl in enhancing the UCS of MICP-treated calcareous sand. The proposed experimental methodology serves as a valuable tool for designing treatment strategies for MICP-cemented calcareous sand in practical engineering applications.

3.
J Hazard Mater ; 459: 132193, 2023 10 05.
Article in English | MEDLINE | ID: mdl-37549579

ABSTRACT

Perfluorooctanoic acid (PFOA) and microcystin-LR (MCLR) are pervasive pollutants in surface waters that induce significant toxic effects on aquatic organisms. However, the combined environmental risk of PFOA and MCLR remains unclear. To assess the toxic effects of PFOA and MCLR on submerged macrophytes and biofilms, Vallisneria natans was exposed to different concentrations of PFOA and MCLR (0.01, 0.1, 1.0 and 10.0 µg L-1). Vallisneria natans was sensitive to high concentrations of MCLR (10 µg L-1): plants exposed to 10 µg L-1 of MCLR measured a biomass of 3.46 g, which was significantly lower than the 8.71 g of the control group. Additionally, antagonistic interactive effects were observed in plants exposed to combined PFOA and MCLR. Exposure to these pollutants adversely affected photosynthesis of the plants and triggered peroxidation that promoted peroxidase, superoxide dismutase and catalase activities, and increased malondialdehyde and glutathione concentrations. The total chlorophyll content was lower in the highest concentration of the combined treatment group (0.443 mg g-1) than in the control group (0.534 mg g-1). Peroxidase activity increased from 662.63 U mg-1 Pr to 1193.45 U mg-1 Pr with increasing PFOA concentrations. Metabolomics indicated that the stress tolerance of Vallisneria natans was improved via altered fatty acid metabolism, hormone metabolism and carbon metabolism. Furthermore, PFOA and MCLR influenced the abundance and structure of the microbial community in the biofilms of Vallisneria natans. The increased contents of autoinducer peptide and N-acylated homoserine lactone signaling molecules indicated that these pollutants altered the formation and function of the biofilm. These results expand our understanding of the combined effects of PFOA and MCLR in aquatic ecosystems.


Subject(s)
Ecosystem , Environmental Pollutants , Microcystins/toxicity , Antioxidants/metabolism , Peroxidases , Biofilms
4.
Appl Biochem Biotechnol ; 195(12): 7197-7213, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36988847

ABSTRACT

Microbially induced calcium carbonate precipitation (MICP) is an immensely growing technique that utilizes the metabolic pathways of bacteria to form calcite precipitation throughout the soil matrix, leading to improve geotechnical engineering properties. However, the excessive number of treatments limited the application of MICP for strengthening calcareous sand. To reduce the number of treatments and develop efficiencies, this paper investigates the optimized treatment protocol of adding aluminum ion flocculants to the cementing solution to accelerate the curing rate of the MICP and its effect. The results show that adding a certain concentration of AlCl3 to the cementing solution can resulted in a rapid increase in strength of the calcareous sand column. When 0.02 M aluminum chloride was added to the cementing solution, the unconfined compressive strength of the sand column reached 827 kPa after three treatments, and it reached 2 MPa after five treatments, while the control group needed to be treated 10 and 15 times, respectively, to reach equivalent strengths. In this paper, the unconfined compressive strength of the sand column formed using the proposed method was 27-40 times that of the control group at the same calcium carbonate content. The presented experimental approach can be used as a tool to design the treatment protocol for the engineering application of MICP-reinforced calcareous sand in practice.


Subject(s)
Aluminum , Sand , Biomineralization , Soil , Calcium Carbonate/metabolism
5.
Cell Oncol (Dordr) ; 46(4): 933-951, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36920729

ABSTRACT

PURPOSE: Urothelial carcinoma (UC) is a common disease in developed counties. This study aimed to identify autocrine roles and signaling pathways of gremlin 1, DAN family BMP antagonist (GREM1), which inhibits tumor growth and epithelial-mesenchymal transition (EMT) in UC. METHODS: Systematic in vitro and in vivo studies using genetic engineering, different urinary bladder urothelial carcinoma (UBUC)-derived cell lines, and mouse models were performed, respectively. Further, primary upper tract urothelial carcinoma (UTUC) and UBUC specimens were evaluated by immunohistochemistry. RESULTS: GREM1 protein levels conferred better disease-specific and metastasis-free survival rates and played an independent prognostic factor in UTUC and UBUC. Hypermethylation is the primary cause of low GREM1 levels. In different UBUC-derived cell lines, the autocrine/secreted and glycosylated GREM1 interacted with transforming growth factor beta 1 (TGFB1) and inhibited TGFß/BMP/SMAD signaling and myosin light chain 9 (MYL9) transactivation, subsequently cell proliferation and epithelial-mesenchymal transition (EMT). Secreted and glycosylated GREM1 also suppressed tumor growth, metastasis, and MYL9 levels in the mouse model. Instead, cytosolic GREM1 promoted cell proliferation and EMT by activating the tumor necrosis factor (TNF)/AKT/nuclear factor kappa B (NFκB) axis. CONCLUSIONS: Clinical associations, animal models, and in vitro indications provided solid evidence to show that the epithelial autocrine GREM1 is a novel tumor suppressor in UCs. The glycosylated-GREM1 hampered cell proliferation, migration, invasion, and in vitro angiogenesis through interaction with TGFB1 to inactivate TGFß/BMP/SMAD-mediated EMT in an autocrine manner.


Subject(s)
Carcinoma, Transitional Cell , Urinary Bladder Neoplasms , Mice , Animals , Transforming Growth Factor beta/metabolism , Epithelial-Mesenchymal Transition/genetics , Urinary Bladder Neoplasms/pathology , Carcinoma, Transitional Cell/genetics , Transcriptional Activation
6.
Front Surg ; 9: 971068, 2022.
Article in English | MEDLINE | ID: mdl-36157430

ABSTRACT

Background: Although the incidence of a single meningioma or a single aneurysm is common, cases of multiple meningiomas combined with multiple aneurysms are rarely reported, and surgical treatment of the coexisting situation is also relatively uncommon. Case presentation: A 38-year-old male patient presented to the neurosurgery department of our center with a headache. Examination revealed only symptoms of headache. Laboratory tests showed only decreased total protein and albumin. Magnetic resonance imaging showed preoccupation with the frontal lobe and the right temple bone. Magnetic resonance angiography and digital subtraction angiography showed two aneurysms in the anterior communicating artery and right anterior cerebral artery. Based on a combination of the patient's history and imaging, we hypothesized that the patient was simultaneously suffering from meningioma and an aneurysm, and both of them are multiple. The patient underwent tumor resection and clipping procedure based on this hypothesis in one surgery. Intraoperative biopsy proved to be a meningioma. The patient was discharged on the 10th postoperative day, and a postoperative follow-up suggested no complications. Conclusion: Multiple meningiomas combined with multiple aneurysms are rare to be reported in the same patient. For those unruptured intracranial aneurysms (UIAs) located in the visual field of craniotomy prepared for brain tumorlike meningioma, it is possible to do the clipping as well. When the meningiomas are multiple, fitted with the surgical indication, and located in a position that cannot be treated in one surgery, this may lead to a two-stage operation, no matter where the UIAs are located.

7.
Genes (Basel) ; 13(8)2022 07 27.
Article in English | MEDLINE | ID: mdl-36011255

ABSTRACT

The brain is considered to be an extremely sensitive tissue to hypoxia, and the brain of fish plays an important role in regulating growth and adapting to environmental changes. As an important aquatic organism in northern China, the economic yield of Takifugu rubripes is deeply influenced by the oxygen content of seawater. In this regard, we performed RNA-seq analysis of T. rubripes brains under hypoxia and normoxia to reveal the expression patterns of genes involved in the hypoxic response and their enrichment of metabolic pathways. Studies have shown that carbohydrate, lipid and amino acid metabolism are significant pathways for the enrichment of differentially expressed genes (DEGs) and that DEGs are significantly upregulated in those pathways. In addition, some biological processes such as the immune system and signal transduction, where enrichment is not significant but important, are also discussed. Interestingly, the DEGs associated with those pathways were significantly downregulated or inhibited. The present study reveals the mechanism of hypoxia tolerance in T. rubripes at the transcriptional level and provides a useful resource for studying the energy metabolism mechanism of hypoxia response in this species.


Subject(s)
Takifugu , Transcriptome , Animals , Brain/metabolism , Gene Expression Profiling , Hypoxia/genetics , Hypoxia/metabolism , Takifugu/genetics , Transcriptome/genetics
9.
Fitoterapia ; 157: 105118, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34974140

ABSTRACT

Melodicochinines A - D (1-4), four new monoterpene indole alkaloids (MIAs), along with 21 known ones, were isolated from the stems and twigs of Melodinus cochinchinensis. Their structures were elucidated on the basis of extensive spectroscopic analysis. A ubiquitin-rhodamine 110 assay showed that 11-methyloxytabersonine had potential inhibitory effect against ubiquitin-specific protease 7 (USP7).


Subject(s)
Apocynaceae/chemistry , Plant Extracts/chemistry , Secologanin Tryptamine Alkaloids/isolation & purification , China , Chromatography, High Pressure Liquid , Magnetic Resonance Spectroscopy , Optical Rotation , Plant Extracts/isolation & purification , Plant Stems/chemistry , Secologanin Tryptamine Alkaloids/chemistry , Spectrophotometry, Infrared
11.
Cancer Manag Res ; 13: 7981-7988, 2021.
Article in English | MEDLINE | ID: mdl-34707404

ABSTRACT

OBJECTIVE: This review aims to clarify the necessity of hepatic hilar lymph node resection on advanced ovarian cancer patients. BACKGROUND: PARP inhibitors and surgery have significantly improved the survival of patients with ovarian cancer. However, for patients with advanced ovarian cancer, there are often extensive epigastric disseminated metastatic lesions, especially the lymph nodes in the hepatic hilar area. Because of the complicated anatomical relationship and lack of experience in this area, this is easily ignored by gynecological oncologists. METHODS: Through the retrieval and analysis of the current database, namely PubMed, Medline, Web of Science, EMBASE, Cochrane Library, and Wangfang, etc., the literature regarding this topic published before March 2021 were thoroughly investigated. CONCLUSION: For the hepatic hilar regional lymph node surgery, through careful preoperative evaluation, surgical-indication clarification, appropriate case selection, standardized surgical operations and multidisciplinary cooperation with general surgeons, the prognosis of patients is significantly improved. Postoperative complications are also safe and controllable and convincing. To conclude, the application of hilar region lymph node cytoreductive surgery for patients with advanced ovarian cancer is a feasible and preferred choice.

12.
Foodborne Pathog Dis ; 18(12): 859-866, 2021 12.
Article in English | MEDLINE | ID: mdl-34415782

ABSTRACT

Antibiotic resistance genes (ARGs) are emerging contaminants that pose a health risk to humans worldwide. Little information on ARGs in bee honey is available. This study profiles ARGs in bee honey samples produced in China, the biggest producer in the world. Of 317 known ARGs encoding resistance to 8 classes of antibiotics, 212 were found in collected honey samples by a real-time quantitative polymerase chain reaction approach. Occurrence frequencies of genes providing resistance to FCA (fluoroquinolone, quinolone, florfenicol, chloramphenicol, and amphenicol) and aminoglycosides were 21.0% and 18.5%, respectively. Frequencies of genes encoding efflux pumps were 42.5% and those of destructase genes 36.6%, indicating that these two mechanisms were predominant for resistance. Nine plasmid-mediated quinolone resistance genes were detected. Of the nine transposase genes known to be involved in antibiotic resistance, eight were found in the samples examined, with tnpA-4, tnpA-5, and tnpA-6 being more abundant. The abundance of the transposase genes was associated with genes conferring resistance to tetracyclines (r = 0.648, p < 0.01), macrolide-lincosamide-streptogramin B (r = 0.642, p < 0.01), FCA (r = 0.517, p < 0.01), and aminoglycosides (r = 0.401, 0.01 < p < 0.05). This is the first study on the abundance and diversity of ARGs in Chinese bee honey products. These findings suggest that bee honey may be a significant source of ARGs that might pose threat to public health. Further research is required to collect more samples in diverse geographic regions in China to make a more comprehensive judgment of ARG in bee honey.


Subject(s)
Anti-Bacterial Agents , Honey , Animals , Anti-Bacterial Agents/pharmacology , China , Drug Resistance, Microbial , Genes, Bacterial , Tetracyclines
13.
Fitoterapia ; 154: 104923, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33984437

ABSTRACT

Acmoxanthones A-E (1-5), five new lavandulylated xanthones, were isolated from the aerial parts of Hypericum acmosepalum, together with four known xanthones. Their structures with absolute configurations were elucidated on the basis of analysis of MS, NMR and chiroptical properties. A bioassay against high glucose-induced damage on human umbilical vein endothelial cells (HUVECs) showed ananixanthone (6) and osajaxanthone (7) had potential antioxidative damage activity with EC50 values of 10.5 µg/mL and 7.6 µg/mL, respectively, while 3-hydroxy-2,4-dimethoxyxanthone (8) exhibited cytotoxic effect on the damaged cells with IC50 values of 7.1 µg/mL.


Subject(s)
Hypericum/chemistry , Xanthones/pharmacology , Antioxidants/isolation & purification , Antioxidants/pharmacology , Human Umbilical Vein Endothelial Cells/drug effects , Humans , Isoflavones , Molecular Structure , Phytochemicals/isolation & purification , Phytochemicals/pharmacology , Plant Components, Aerial/chemistry , Xanthones/isolation & purification
14.
Phytochemistry ; 187: 112771, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33882428

ABSTRACT

Uralins A - D, four undescribed polycyclic polyprenylated acylphloroglucinols (PPAPs) featuring an unprecedented fused hexacyclic architecture, a unique monocyclic tetra-seco-tetranor-b-PPAP, an oxidative b-PPAP and a rare norspiroindane-type m-PPAP, respectively, were isolated from the aerial parts of Hypericum uralum, along with ten known PPAPs. Their structures and absolute configurations were elucidated by extensive spectroscopic techniques (MS, NMR, [α]D, CD), conceivable biogenetic pathways and time-dependent density functional theory-based electronic circular dichroism (TDDFT-ECD) calculations. Biological assays showed three b-PPAPs had moderate antioxidative damage activities, while spiroindanes exhibited moderate cytotoxic effects.


Subject(s)
Hypericum , Circular Dichroism , Magnetic Resonance Spectroscopy , Molecular Structure , Phloroglucinol/pharmacology
15.
Sci Adv ; 6(46)2020 Nov.
Article in English | MEDLINE | ID: mdl-33177088

ABSTRACT

Rapid development of artificial intelligence techniques ignites the emerging demand on accurate perception and understanding of optical signals from external environments via brain-like visual systems. Here, enabled by quasi-two-dimensional electron gases (quasi-2DEGs) in InGaO3(ZnO)3 superlattice nanowires (NWs), an artificial visual system was built to mimic the human ones. This system is based on an unreported device concept combining coexistence of oxygen adsorption-desorption kinetics on NW surface and strong carrier quantum-confinement effects in superlattice core, to resemble the biological Ca2+ ion flux and neurotransmitter release dynamics. Given outstanding mobility and sensitivity of superlattice NWs, an ultralow energy consumption down to subfemtojoule per synaptic event is realized in quasi-2DEG synapses, which rivals that of biological synapses and now available synapse-inspired electronics. A flexible quasi-2DEG artificial visual system is demonstrated to simultaneously perform high-performance light detection, brain-like information processing, nonvolatile charge retention, in situ multibit-level memory, orientation selectivity, and image memorizing.

16.
Medicine (Baltimore) ; 99(7): e19042, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32049802

ABSTRACT

BACKGROUND: This meta-analysis was conducted to compare the effects and safety of teriparatide with risedronate in the treatment of osteoporosis. MATERIAL AND METHODS: PubMed, Embase, Web of Science and Cochrane library database were systematically reviewed for studies published up to February 24, 2019. Eligible studies that compared the effects of teriparatide with risedronate in osteoporosis were included in this meta-analysis. The outcomes included percentage change in bone mineral density (BMD) of lumbar spine, femoral neck, and total hip, the incidence of clinical fractures, serum bone markers, and adverse events. A random-effects or fixed-effects model was used to pool the estimate, according to the heterogeneity among the included studies. RESULTS: Seven studies were included in this meta-analysis. Compared with risedronate, teriparatide was associated with a significant increase in lumbar spine BMD [weight mean difference (WMD)=4.24, 95%CI: 3.11, 5.36; P < .001], femoral neck BMD (WMD=2.28, 95%CI: 1.39, 3.18; P < .001), and total hip BMD (WMD = 1.19, 95%CI: 0.47, 1.91; P = .001). Moreover, patients in teriparatide group had significantly lower incidences of clinical fracture (risk ratio [RR] = 0.48, 95%CI: 0.32, 0.72; P < .001), new vertebral fracture (RR = 0.45, 95%CI: 0.32, 0.63; P < .001), and non-vertebral fracture (RR = 0.63, 95%CI: 0.40, 0.98; P = .042) than those in risedronate group. There were significant differences between the 2 groups in serum change, including P1NP (WMD = 122.34, 95%CI: 68.89, 175.99; P < .001), CTx (WMD = 0.62, 95%CI: 0.29, 0.96; P < .001), and iPTH (WMD = -13.18, 95%CI: -15.04, -11.33; P < .001). The incidence of adverse events was similar between the 2 groups (RR = 0.93, 95%CI: 0.69, 1.25; P = .610). CONCLUSION: This study suggested that teriparatide was more effective than risedronate for increasing the BMD in lumbar spine, femoral neck, and total hip, as well as reducing the incidences of clinical fracture, new vertebral fracture and non-vertebral fracture. There was no significant difference in incidence of adverse events between the 2 drugs. Considering the potential limitations in the present study, further large-scale, well-performed randomized trials are needed to verify our findings.


Subject(s)
Osteoporosis/drug therapy , Risedronic Acid/therapeutic use , Teriparatide/therapeutic use , Bone Density/drug effects , Female , Humans , Randomized Controlled Trials as Topic , Risedronic Acid/adverse effects , Risedronic Acid/pharmacology , Teriparatide/adverse effects , Teriparatide/pharmacology , Treatment Outcome
17.
ACS Appl Mater Interfaces ; 11(42): 38633-38640, 2019 Oct 23.
Article in English | MEDLINE | ID: mdl-31550123

ABSTRACT

Despite the recent advances in electrochemical water splitting, developing cost-effective and highly efficient electrocatalysts for oxygen evolution reaction (OER) still remains a substantial challenge. Herein, two-dimensional cobalt phosphate hydroxides (Co5(PO4)2(OH)4) nanosheets, a unique stacking-disordered phosphate-based inorganic material, are successfully prepared via a facile and scalable method for the first time to serve as a superior and robust electrocatalyst for water oxidation. On the basis of the detailed characterization (e.g., X-ray absorption near-edge structure and X-ray photoelectron spectroscopy), the obtained nanosheets consist of special zigzag CoO6 octahedral chains along with intrinsic lattice distortion and excellent hydrophilicity, in which these factors contribute to the highly efficient performance of prepared electrocatalysts for OER. Specifically, Co5(PO4)2(OH)4 deposited on glassy carbon electrode (loading amount ≈0.553 mg cm-2) can exhibit an unprecedented overpotential of 254 mV to drive a current density of 10 mA cm-2 with a small Tafel slope of 57 mV dec-1 in alkaline electrolytes, which outperforms the ones of CO3(PO4)2 (370 mV) and Co(OH)2 (360 mV) as well as other advanced catalysts. Evidently, this work has opened a new pathway to the rational design of promising metal phosphate hydroxides toward the efficient electrochemical energy conversion.

18.
ACS Appl Mater Interfaces ; 11(38): 35238-35246, 2019 Sep 25.
Article in English | MEDLINE | ID: mdl-31462044

ABSTRACT

Because of their fascinating properties, two-dimensional (2D) nanomaterials have attracted a lot of attention for developing next-generation electronics and optoelectronics. However, there is still a lack of cost-effective, highly reproducible, and controllable synthesis methods for developing high-quality semiconducting 2D monolayers with a sufficiently large single-domain size. Here, utilizing a NaOH promoter and W foils as the W source, we have successfully achieved the fabrication of ultralarge single-domain monolayer WS2 films via a modified chemical vapor deposition method. With the proper introduction of a NaOH promoter, the single-domain size of monolayer WS2 can be increased to 550 µm, while the WS2 flakes can be well controlled by simply varying the growth duration and oxygen concentration in the carrier gas. Importantly, when they are fabricated into global backgated transistors, WS2 devices exhibit respectable peak electron mobility up to 1.21 cm2 V-1 s-1, which is comparable to those of many state-of-the-art WS2 transistors. Photodetectors based on these single-domain WS2 monolayers give an impressive photodetection performance with a maximum responsivity of 3.2 mA W-1. All these findings do not only provide a cost-effective platform for the synthesis of high-quality large single-domain 2D nanomaterials, but also facilitate their excellent intrinsic material properties for the next-generation electronic and optoelectronic devices.

19.
ACS Appl Mater Interfaces ; 11(36): 33012-33021, 2019 Sep 11.
Article in English | MEDLINE | ID: mdl-31414595

ABSTRACT

Spinel oxides (AB2O4) with unique crystal structures have been widely explored as promising alternative catalysts for efficient oxygen evolution reactions; however, developing novel methods to fabricate robust, cost-effective, and high-performance spinel oxide based electrocatalysts is still a great challenge. Here, utilizing a complementary experimental and theoretical approach, pentavalent vanadium doping in the spinel oxides (i.e., Co3O4 and NiFe2O4) has been thoroughly investigated to engineer their surface structures for the enhanced electrocatalytic oxygen evolution reaction. Specifically, when the optimal concentration of vanadium (ca. 7.7 at. %) is incorporated into Co3O4, the required overpotential to reach a certain jGEOM and jECSA decreases dramatically for oxygen evolution reactions in alkaline media. Even after 30 h of chronopotentiometry, the required potential for V-doped Co3O4 just increases by 16.3 mV, being much lower than that of the undoped one. It is observed that the pentavalent vanadium doping introduces lattice distortions and defects on the surface, which in turn exposes more active sites for reactions. DFT calculations further reveal the rate-determining step changing from the step of *-O to *-OOH to the step of *-OH to *-O, while the corresponding energy barriers decrease from 1.73 to 1.57 eV accordingly after high-valent V doping. Moreover, the oxygen intermediate probing method using methanol as a probing reagent also demonstrates a stronger OH* adsorption on the surface after V doping. When vanadium doping is performed in the inverse spinel matrix of NiFe2O4, impressive performance enhancement in the oxygen evolution reaction is as well witnessed. All these results clearly illustrate that the V doping process can not only efficiently improve the electrochemical properties of spinel transition metal oxides but also provide new insights into the design of high-performance water oxidation electrocatalysts.

20.
ACS Nano ; 13(5): 6060-6070, 2019 May 28.
Article in English | MEDLINE | ID: mdl-31067402

ABSTRACT

Controlled synthesis of lead halide perovskite (LHP) nanostructures not only benefits fundamental research but also offers promise for applications. Among many synthesis techniques, although catalytic vapor-liquid-solid (VLS) growth is recognized as an effective route to achieve high-quality nanostructures, until now, there is no detailed report on VLS grown LHP nanomaterials due to the emerging challenges in perovskite synthesis. Here, we develop a direct VLS growth for single-crystalline all-inorganic lead halide perovskite ( i.e., CsPbX3; X = Cl, Br, or I) nanowires (NWs). These NWs exhibit high-performance photodetection with the responsivity exceeding 4489 A/W and detectivity over 7.9 × 1012 Jones toward the visible light regime. Field-effect transistors (FET) based on individual CsPbX3 NWs are also fabricated, where they show the superior hole mobility of up to 3.05 cm2/(V s), higher than other all-inorganic LHP devices. This work provides important guidelines for the further improvement of these perovskite nanostructures for utilizations.

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