Most doping research into transition metal dichalcogenides (TMDs) has been mainly focused on the improvement of electronic device performance. Here, the effect of self‐assembled monolayer (SAM)‐based ...doping on the performance of WSe2‐ and MoS2‐based transistors and photodetectors is investigated. The achieved doping concentrations are ≈1.4 × 1011 for octadecyltrichlorosilane (OTS) p‐doping and ≈1011 for aminopropyltriethoxysilane (APTES) n‐doping (nondegenerate). Using this SAM doping technique, the field‐effect mobility is increased from 32.58 to 168.9 cm2 V−1 s in OTS/WSe2 transistors and from 28.75 to 142.2 cm2 V−1 s in APTES/MoS2 transistors. For the photodetectors, the responsivity is improved by a factor of ≈28.2 (from 517.2 to 1.45 × 104 A W−1) in the OTS/WSe2 devices and by a factor of ≈26.4 (from 219 to 5.75 × 103 A W−1) in the APTES/MoS2 devices. The enhanced photoresponsivity values are much higher than that of the previously reported TMD photodetectors. The detectivity enhancement is ≈26.6‐fold in the OTS/WSe2 devices and ≈24.5‐fold in the APTES/MoS2 devices and is caused by the increased photocurrent and maintained dark current after doping. The optoelectronic performance is also investigated with different optical powers and the air‐exposure times. This doping study performed on TMD devices will play a significant role for optimizing the performance of future TMD‐based electronic/optoelectronic applications.
High‐performance transition metal dichalcogenides (TMD) photodetectors are enhanced by self‐assembled monolayer (SAM) doping. The photoresponsivity of WSe2 and MoS2 photodetectors is improved by a factor of ≈28.2 (with OTS p‐doping) and ≈26.4 (with APTES n‐doping), respectively. These improvements are attributed to the enhancement of TMD optical properties by SAM doping and this is also investigated in detail through photoluminescence analysis.
Structural pulverization of metal chalcogenides such as Sn-based compounds is a serious issue for development of high-performance anode materials and results in serious capacity fading during ...continuous charge and discharge cycles. In this work, we synthesize ultrasmall SnS quantum dots (QDs) anchored onto nitrogen-enriched carbon (NC) nanospheres through facile hydrothermal and carbonization processes to prepare a progressive anode material for sodium-ion batteries. The optimized SnS QDs@NC electrode delivered an initial discharge capacity of 281 mAh g–1 at 100 mA g–1 and exhibited excellent cycling stability with a capacity retention of 75% after 500 cycles at a high current density of 1000 mA g–1. Ex situ XRD, XPS, FE-SEM, TEM measurements, and kinetics study were performed to unveil the sodium storage mechanism of the SnS QDs@NC electrode. A sodium-ion full cell assembled with an SnS QDs@NC anode and a Na3V2(PO4)3 cathode exhibited high capacity and good cycling stability. Such a superior electrochemical performance of SnS QDs@NC can be attributed to the synergistic effects of NC and SnS QDs where NC serves as a conducting matrix to support SnS QDs and helps avoid structural degradation. This work provides a promising strategy to resolve the pulverization issue of alloying and conversion-type anode materials.
Sodium batteries have been recognized as a promising alternative to lithium‐ion batteries. However, the liquid electrolyte used in these batteries has inherent safety problems. Polymer electrolytes ...have been considered as safer and more reliable electrolyte systems for rechargeable batteries. Herein, a thermoplastic polyurethane elastomer‐based gel polymer electrolyte with high ionic conductivity and high elasticity was reported. It had an ambient‐temperature ionic conductivity of 1.5 mS cm−1 and high stretchability, capable of withstanding 610 % strain. Coordination between Na+ ions and polymer chains increased the degree of salt dissociation in the gel polymer electrolyte compared with the liquid electrolyte. An Na/Na3V2(PO4)3 cell assembled with gel polymer electrolyte exhibited good cycling performance in terms of discharge capacity, cycling stability, and rate capability, which was owing to the effective trapping ability of organic solvents in the polymer matrix and uniform flux of sodium ions through the gel polymer electrolyte.
A gel solution: A sodium‐metal cell fabricated with a sodium‐metal anode, an Na3V2(PO4)3 cathode, and a gel polymer electrolyte based on a thermoplastic polyurethane elastomer exhibits good cycling performance in terms of discharge capacity, cycling stability, and rate capability owing to effective trapping of organic solvents in the polymer matrix and uniform sodium‐ion flux through the gel polymer electrolyte.
In this work, we demonstrate the FeS2/MoS2 composite embedded in rGO nanosheets (FeS2/MoS2-rGO composite) as an anode material for sodium-ion battery. The FeS2/MoS2 composite material was synthesized ...by one step hydrothermal method, and the prepared particles were wrapped by reduced graphene oxide (rGO) nanosheets, which facilitated the electronic transport between the particles, and suppressed the volume expansion of active materials as well as the polysulfide dissolution into the electrolyte during cycling. The FeS2/MoS2-rGO composite electrode delivered a high initial discharge capacity of 468.0 mA h g−1 and exhibited good cycling stability at a current density of 100 mA g−1. Due to the pseudocapacitive behavior of FeS2/MoS2-rGO electrode, a high reversible capacity of 346.5 mA h g−1 was achieved at 3000 mA g−1, which was much higher than those of FeS2, MoS2 and FeS2/MoS2 composite electrodes. The sodium-ion full cell assembled with FeS2/MoS2-rGO composite anode and Na3V2(PO4)2F3 cathode exhibited a high reversible capacity with good cycling stability, which demonstrates that the prepared FeS2/MoS2-rGO composite can be used as a promising anode material for sodium-ion batteries.
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•FeS2/MoS2 composite embedded in rGO nanosheets is synthesized as an anode material.•The FeS2/MoS2-rGO delivers a high discharge capacity of 346.5 mA h g−1 at 3000 mA g−1.•Pseudo capacitive nature of FeS2/MoS2-rGO leads to a fast electrode kinetics.•Sodium-ion full cell assembled with FeS2/MoS2-rGO exhibits good cycling performance.
Solid polymer electrolytes composed of poly(ε-caprolactone) (PCL) and lithium bis(trifluoromethane) sulfonylimide (LiTFSI) salt were prepared for investigating their electrochemical properties. The ...optimized solid polymer electrolyte showed ionic conductivities of 2.5 × 10−5 and 1.6 × 10−4 S cm−1 at room temperature and 55 °C, respectively. Dimensional stability was improved by infiltrating PCL-based solid polymer electrolyte into the porous polymer membranes prepared from poly(ether imide) (PEI), polyacrylonitrile (PAN) and non-woven polypropylene (PP) membranes. Due to the highly porous nature and good compatibility of the PEI membrane toward the PCL-based solid polymer electrolyte, a solid-state Li/LiNi0.6Co0.2Mn0.2O2 cell assembled with a solid polymer electrolyte employing a PEI membrane exhibited the best cycling performance. Based on our results, this highly porous PEI membrane is proposed as a promising supporting membrane for enhancing the mechanical stability of amorphous solid polymer electrolytes for applications in all-solid-state lithium batteries.
•Solid polymer electrolytes based on PCL are prepared and characterized.•They exhibit fully amorphous characteristics and high ionic conductivity.•Membrane-supported SPEs show high anodic stability and good mechanical properties.•All-solid-state cell employing porous PEI membrane exhibits good cycling performance.
We present a simple and effective method for the interactive segmentation of feature regions in a triangular mesh. From the user‐specified radius and click position, the candidate region that ...contains the desired feature region is defined as geodesic disc on a triangle mesh. A concavity‐aware harmonic field is then computed on the candidate region using the appropriate boundary constraints. An initial isoline is chosen by evaluating the uniformly sampled ones on the harmonic field based on the gradient magnitude. A set of feature points on the initial isoline is selected and the anisotropic geodesics passing through them are then determined as the final segmentation boundary, which is smooth and locally shortest. The experimental results show several segmentation results for various 3D models, revealing the effectiveness of the proposed method.
We present a simple and effective method for the interactive segmentation of feature regions in a triangular mesh. The experimental results show several segmentation results for various 3D models, revealing the effectiveness of the proposed method.
The aim of the present paper was to assess and compare the long‐term efficacy and safety of single‐incision mini‐slings (SIMSs), except tension‐free vaginal tape (TVT)‐Secur, with standard ...midurethral slings (SMUSs) for female stress urinary incontinence through an updated systematic review and meta‐analysis of randomized controlled trials (RCTs) comparing these two surgical methods. A literature review of all RCTs comparing SIMSs (Mini‐Arc, Contasure‐Needleless, Ophira, Tissue Fixation System and Ajust), except TVT‐Secur, with SMUSs was performed. The Medline, Embase, Scopus, Web of Science and Cochrane Controlled Trial Register databases were reviewed. We retrieved 29 RCTs (including a total of 2 986 patients) that compared SIMSs, except TVT‐Secur, with SMUSs. Meta‐analysis of long‐term results showed no significant difference in the patient‐reported cure rate (odds ratio OR 0.67, 95% confidence interval CI 0.44–1.60); however, we found that SMUSs had a significantly superior objective cure rate (OR 0.68, 95% CI 0.47–0.99; P = 0.04). SIMSs were associated with a significantly shorter operation time, lower immediate postoperative pain based on a visual analogue scale score, lower intra‐operative blood loss, and lower postoperative voiding dysfunction. The meta‐analysis showed clear evidence of the superiority of SMUSs over SIMSs, except TVT‐Secur, in terms of the objective cure rate, after long‐term follow‐up; however, SIMSs were superior with respect to immediate postoperative pain, intra‐operative blood loss, and postoperative voiding dysfunction.
Aims
We investigated surgical outcomes and changes of overactive bladder (OAB) symptoms after midurethral sling in female stress urinary incontinence (SUI) patients with or without neurological ...disease (ND) without spinal cord injury.
Methods
Patients who underwent midurethral sling for SUI between January 2009 and December 2018 were reviewed. Postoperative changes in OAB symptoms (de novo occurrence or resolution) within 1 year were compared in each preoperative symptom subset with a 1:1 matched analysis between non‐neurological disease (NND) and ND group.
Results
A total of 855 patients (median follow‐up: 49.8 months; mean age: 57.9 ± 9.3 years) were included. Successful SUI correction was achieved in 95.0% of NND and 93.7% of ND patients (p = .440). Among 797 patients (711 NND and 86 ND) without remnant SUI, 227 had SUI only, 198 had SUI with urgency, and 372 had mixed urinary incontinence (MUI) preoperatively. The ND patients tended to be older (62.8 ± 9.2 vs. 57.2 ± 9.0 years) and had higher proportions of diabetes (24.4% vs. 8.0%), hypertension (47.7% vs. 26.7%), and MUI (64.0% vs. 44.6%) than NND patients (p < .001, respectively). After matching age, diabetes, and hypertension, the incidence of de novo OAB was higher in ND patients (SUI only; 21.1% vs. 5.3%; p < .001) while resolution rates of urgency urinary incontinence (UUI) were similar (MUI; 57.7% vs. 53.9%; p = .414).
Conclusions
Success rates of midurethral sling and resolution of UUI were comparable between NND and ND patients. In patients with neurological conditions, de novo OAB symptoms were more likely to develop.
Heart failure (HF) is an important cardiovascular disease because of its increasing prevalence, significant morbidity, high mortality, and rapidly expanding health care cost. The number of HF ...patients is increasing worldwide, and Korea is no exception. There have been marked advances in definition, diagnostic modalities, and treatment of HF over the past four decades. There is continuing effort to improve risk stratification of HF using biomarkers, imaging and genetic testing. Newly developed medications and devices for HF have been widely adopted in clinical practice. Furthermore, definitive treatment for end-stage heart failure including left ventricular assist device and heart transplantation are rapidly evolving as well. This review summarizes the current state-of-the-art management for HF and the emerging diagnostic and therapeutic modalities to improve the outcome of HF patients.
To investigate the therapeutic effects of axitinib, a tyrosine kinase inhibitor, in an interstitial cystitis (IC) rat model. IC patients with or without Hunner lesion and non-IC controls were ...enrolled (n = 5/group). Bladder tissues were stained with vascular endothelial growth factor (VEGF), VEGF receptor 2 (VEGFR-2), platelet-derived growth factor (PDGF), and PDGF receptor B (PDGFR-B). The IC group showed extensive VEGFR-2 and PDGFR-B staining compared with controls. Next, ten-week-old female Sprague Dawley rats were divided into three groups (n = 10/group): sham, hydrochloride (HCl), and axitinib groups. One week after HCl instillation (day 0), the axitinib group received oral axitinib (1 mg/kg) for five consecutive days and pain was evaluated daily. Bladder function, histology and genetics were evaluated on day 7. The pain threshold significantly improved 3 days after axitinib administration. Axitinib decreased non-voiding contraction and increased the micturition interval and micturition volume and alleviated urothelial denudation, angiogenesis, mast cell infiltration, and fibrosis. HCl instillation increased the expression of tyrosine kinase receptors, including VEGFR-2 and PDGFR-B; axitinib administration inhibited their expression. Oral administration of axitinib improved pain, voiding profiles, and urothelial integrity by inhibiting angiogenesis in IC rat model. Axitinib may have potential therapeutic efficacy in IC patients.
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