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1.
Surg Neurol Int ; 15: 315, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39372975

RESUMEN

Background: Herniated nucleus pulposus (HNP), without causing significant neurological deficit, is a more frequently occurring disease of the spine affecting the activities of daily living with chronic back pain and sometimes progressing to produce significant functional deficit. Trans-sacral epiduroscopic laser decompression (SELD) is being increasingly used as a treatment modality for these conditions and has been shown to give effective results. We present the clinical outcomes of the patients undergoing SELD in our institute for HNP. Methods: A retrospective study of 411 patients who underwent SELD for lumbar disc herniation was done, analyzing the clinical outcomes by measuring visual analog scale (VAS) scores for leg pain and back pain, Oswestry Disability Index (ODI) score, and Short form health survey (SF -36) scores and followed up for 6 months. Results: A total of 195 males and 216 females underwent SELD, with a mean age of 33.2 ± 0.9 years and a mean follow-up period of 7 ± 1.6 months. VAS scores for back pain and leg pain improved significantly from 6.9 ± 0.5 and 6.6 ± 0.6 preoperatively to 1.1 ± 0.5 (P > 0.05) and 0.4 ± 0.5 (P > 0.05) at 6 months. ODI score decreased from 28.2 ± 1.7 to 9.4 ± 1.7 at 6 months from the intervention (P < 0.05). SF-36 showed significant improvement in overall categories through 6 months of follow-up. Twenty-four patients had dural punctures, and four patients needed blood patches but recovered without any complications. One patient had aggravation of the disc herniation post-procedure, and was managed by endoscopic discectomy. Conclusion: SELD is a safe, accurate, and effective procedure in treating symptomatic lumbar disc herniation with excellent clinical outcomes and effective pain relief with minimal damage to paraspinal muscles with an easier learning curve, reproducible results, and high safety index.

2.
Asian Spine J ; 18(4): 514-521, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39168467

RESUMEN

STUDY DESIGN: Retrospective study. PURPOSE: This study aimed to propose a method of performing unilateral biportal endoscopy (UBE)-assisted interbody cage insertion for fusion using the "insert and revolve" technique and analyze the clinico-radiological outcomes. OVERVIEW OF LITERATURE: UBE-assisted lumbar interbody fusion (ULIF) is a rapidly evolving technique combining the advantages of minimally invasive technique with ease of learning. The limited size of cages was a result of the narrow insertion channel. We propose a technique in which large extreme lateral interbody fusion cages can be inserted through the same opening. METHODS: This study included 104 patients who underwent ULIF using the "insert and revolve technique" between July 2019 and September 2022. The patients were followed up for at least 12 months postoperatively. The clinical outcomes were assessed using the Visual Analog Scale (VAS) for leg pain and back pain, Oswestry Disability Index (ODI), and modified McNab's criteria. Changes in segmental lordosis (SL), intervertebral disc height (IVDH), segmental coronal alignment (SCA), cage subsidence, and fusion grade were evaluated at 6- and 12-month follow-up. RESULTS: The VAS scores for leg and back pain and ODI score showed significant improvement. Based on the Macnab's criteria, 97 patients showed excellent outcomes and seven demonstrated good outcomes at 12 months. The mean IVDH increased from 6.3±2 to 10±2.1 mm immediately after surgery and 10±1.1 mm at 6 months. SL improved from 9.3°±11.5° to 17.78°±8.1°, while SCA improved from 7.7°±2.1° to 3.4°±1.2° at 1 year. Moreover, 92 and 11 patients showed grade 1 and 2 fusion, respectively, according to the Bridwell grading at 1 year. CONCLUSIONS: The "insert and revolve technique" facilitates the successful insertion of large cages, contributing to the restoration of disc height and coronal and sagittal spinal correction with favorable fusion rates.

3.
Oncol Lett ; 28(2): 388, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38966587

RESUMEN

Atezolizumab/bevacizumab is the first line of treatment for unresectable hepatocellular carcinoma (HCC), combining immune checkpoint inhibitor and anti-VEGF monoclonal antibodies. Hepatic arterial infusion chemotherapy (HAIC) is administered when the above-described combination fails to confer sufficient clinical benefit. The present study aimed to explore the association between tumor programmed cell death-ligand 1 (PD-L1) positivity and HAIC response. A total of 40 patients with HCC who had undergone HAIC with available biopsy samples obtained between January 2020 and May 2023 were retrospectively enrolled. Tumor response, progression-free survival (PFS), disease control rate (DCR) and overall survival (OS) were evaluated. PD-L1 expression in tumor samples was assessed using a combined positivity score. The response rates of HAIC-treated patients with advanced HCC after failure of atezolizumab/bevacizumab combination therapy were recorded. OS (P=0.9717) and PFS (P=0.4194) did not differ between patients with and without PD-L1 positivity. The objective response rate (P=0.7830) and DCR (P=0.7020) also did not differ based on PD-L1 status. In conclusion, the current findings highlight the consistent efficacy of HAIC, regardless of PD-L1 positivity.

4.
Sci Rep ; 14(1): 10067, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698148

RESUMEN

In this paper, the floating body effect (FBE) in indium-gallium-zinc-oxide (IGZO) thin-film transistor (TFT) and the mechanism of device failure caused by that are reported for the first time. If the toggle AC pulses are applied to the gate and drain simultaneously for the switching operation, the drain current of IGZO TFT increases dramatically and cannot show the on/off switching characteristics. This phenomenon was not reported before, and our study reveals that the main cause is the formation of a conductive path between the source and drain: short failure. It is attributed in part to the donor creation at the drain region during the high voltage (Vhigh) condition and in part to the donor creation at the source region during the falling edge and low voltage (Vlow) conditions. Donor creation is attributed to the peroxide formation in the IGZO layer induced by the electrons under the high lateral field. Because the donor creation features positive charges, it lowers the threshold voltage of IGZO TFT. In detail, during the Vhigh condition, the donor creation is generated by accumulated electrons with a high lateral field at the drain region. On the other hand, the floating electrons remaining at the short falling edge (i.e., FBE of the IGZO TFT) are affected by the high lateral field at the source region during the Vlow condition. As a result, the donor creation is generated at the source region. Therefore, the short failure occurs because the donor creations are generated and expanded to channel from the drain and source region as the AC stress accumulates. In summary, the FBE in IGZO TFT is reported, and its effect on the electrical characteristics of IGZO TFT (i.e., the short failure) is rigorously analyzed for the first time.

5.
ACS Omega ; 8(48): 45547-45556, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38075810

RESUMEN

With the inherent sleep and wake cycle regulated by natural sunlight, the human body has evolved over millennia to be active during the day and to rest at night. However, maintaining an optimal 24 h cycle has become increasingly problematic in modern society as more people spend the majority of the day indoors. Many research groups have reported that inadequate artificial lighting interferes with melatonin production and disrupts the circadian rhythm. This study considered biological functions for light-emitting diodes (LEDs) of next-generation illumination, and LED packages and spectra suitable for both daytime and nighttime applications were designed. The prepared daytime human-centric (HC)-LEDs had a melanopic/photopic (M/P) ratio that was up to 26% higher than that of conventional (c)-LEDs, whereas the nighttime HC-LEDs exhibited up to a 26% lower M/P ratio compared to the c-LEDs. Nevertheless, because the HC-LED is designed to have almost the same color coordinates as the c-LED having the same correlated-color temperature (CCT), there is no change in the perceived color. To substantiate the biological effect, melatonin level data were obtained from 22 voluntary participants in c- and HC-LED lighting environments. In the HC-LED lighting environment, melatonin was suppressed by 21.9% after waking, and nocturnal melatonin secretion was increased by up to 12.2%. As human-centric lighting, our HC-LEDs are expected to become an essential element for modern life, where people spend most of their time indoors.

6.
Sci Rep ; 13(1): 17590, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37845374

RESUMEN

Oxide semiconductor thin-film transistors (TFTs) are used in the pixel array and gate driver circuits of organic light emitting diode (OLED) display panels. Long-term reliability characteristics of the TFTs are a barometer of the lifetime of OLED display panels. The long-term reliability of the driver TFTs is evaluated in a short time under high voltages and high temperature for an accelerated degradation test. If reliability parameters from the power law or stretched-exponential functions are the same for individual devices and devices in an operating panel, the lifetime of the panel can be accurately estimated. However, since compensation circuits are designed into operating panels, an environmental discrepancy exists between the accelerated test of single devices and the operation of devices in the panel. Herein, we propose a novel compensation stretched-exponential function (CSEF) model which captures the effect of the threshold voltage compensation circuit in the panel. The CSEF model not only bridges the discrepancy between individual devices and panel devices, but also provides a method to accurately and efficiently estimate the long-term lifetime of all display panels that utilize compensation circuits.

7.
Cancers (Basel) ; 15(17)2023 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-37686509

RESUMEN

This study aimed to compare the prognosis and characteristics of patients with advanced hepatocellular carcinoma treated with first-line atezolizumab plus bevacizumab (AB) combination therapy and hepatic artery infusion chemotherapy (HAIC). We retrospectively assessed 193 and 114 patients treated with HAIC and AB combination therapy, respectively, between January 2018 and May 2023. The progression-free survival (PFS) of patients treated with AB combination therapy was significantly superior to that of patients treated with HAIC (p < 0.05), but there was no significant difference in overall survival (OS). After propensity score matching, our data revealed no significant differences in OS and PFS between patients who received AB combination therapy and those who received HAIC therapy (p = 0.5617 and 0.3522, respectively). In conclusion, our propensity score study reveals no significant differences in OS and PFS between patients treated with AB combination therapy and those treated with HAIC.

8.
Micromachines (Basel) ; 13(10)2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36295983

RESUMEN

This paper introduces a compact SPICE model of a two-terminal memory with a Pd/Ti/IGZO/p+-Si structure. In this paper, short- and long-term components are systematically separated and applied in each model. Such separations are conducted by the applied bias and oxygen flow rate (OFR) during indium gallium zinc oxide (IGZO) deposition. The short- and long-term components in the potentiation and depression curves are modeled by considering the process (OFR of IGZO) and bias conditions. The compact SPICE model with the physical mechanism of SiO2 modulation is introduced, which can be useful for optimizing the specification of memristor devices.

9.
Nanomaterials (Basel) ; 12(20)2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36296772

RESUMEN

In this article, we study the post-annealing effect on the synaptic characteristics in Pd/IGZO/SiO2/p+-Si memristor devices. The O-H bond in IGZO films affects the switching characteristics that can be controlled by the annealing process. We propose a switching model based on using a native oxide as the Schottky barrier. The barrier height is extracted by the conduction mechanism of thermionic emission in samples with different annealing temperatures. Additionally, the change in conductance is explained by an energy band diagram including trap models. The activation energy is obtained by the depression curve of the samples with different annealing temperatures to better understand the switching mechanism. Moreover, our results reveal that the annealing temperature and retention can affect the linearity of potentiation and depression. Finally, we investigate the effect of the annealing temperature on the recognition rate of MNIST in the proposed neural network.

10.
Nanomaterials (Basel) ; 12(14)2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35889553

RESUMEN

Here, highly transparent nanocomposite films with an adjustable refractive index were fabricated through stable dispersion of ZrO2 (n = 2.16) nanoparticles (NPs) subjected to surface modification with SiO2 (n = 1.46) in polydimethylsiloxane (PDMS) (n = 1.42) using the Stöber method. ZrO2 NPs (13.7 nm) were synthesized using conventional hydrothermal synthesis, and their surface modification with SiO2 (ZrO2@SiO2 NPs) was controlled by varying the reaction time (3-54 h). The surface modification of the NPs was characterized using Fourier-transform infrared spectroscopy, dynamic light scattering, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, and ellipsometry. The surface modification was monitored, and the effective layer thickness of SiO2 varied from 0.1 nm to 4.2 nm. The effective refractive index of the ZrO2@SiO2 NPs at λ = 633 nm was gradually reduced from 2.16 to 1.63. The 100 nm nanocomposite film was prepared by spin-coating the dispersion of ZrO2@SiO2 NPs in PDMS on the coverslip. The nanocomposite film prepared using ZrO2@SiO2 NPs with a reaction time of 18 h (ZrO2@SiO2-18h-PDMS) exhibited excellent optical transparency (Taverage = 91.1%), close to the transparency of the coverslip (Taverage = 91.4%) in the visible range, and an adjustable refractive index (n = 1.42-1.60) as the NP content in the film increased from 0 to 50.0 wt%.

11.
ACS Appl Mater Interfaces ; 14(1): 1389-1396, 2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-34978416

RESUMEN

Amorphous oxide semiconductor transistors control the illuminance of pixels in an ecosystem of displays from large-screen TVs to wearable devices. To satisfy application-specific requirements, oxide semiconductor transistors of various cation compositions have been explored. However, a comprehensive study has not been carried out where the influence of cation composition, oxygen, and hydrogen on device characteristics and stability is systematically quantified, using commercial-grade process technology. In this study, we fabricate self-aligned top-gate structure thin-film transistors with three oxide semiconductor materials, InGaZnO (In/Ga/Zn = 1:1:1), In-rich InGaZnO, and InZnO, having mobility values of 10, 27, and 40 cm2/V·s, respectively. Combinations of varied amounts of oxygen and hydrogen are incorporated into each transistor by controlling the fabrication process to study the effect of these gaseous elements on the physical nature of the channel material. Electrons can be captured by peroxy linkage (O22-) or undercoordinated In (In* to become In+), which are manifested in the extracted subgap density-of-states profile and first-principles calculations. Energy difference between electron-trapped In+ and O22- σ* is the smallest for IGZO, and In+-O22- annihilation occurs by electron excitation from the subgap In+ state to the O22- σ*. Furthermore, characteristic time constants during positive bias stress and recovery reveal the various microscopic physical phenomena within the transistor structure between different cation compositions.

12.
J Korean Neurosurg Soc ; 64(6): 843-852, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34619822

RESUMEN

The purpose of this review was to synthesize the research on global spinal alignment and reciprocal changes following cervical or thoracolumbar reconstruction surgery. We carried out a search of PubMed, EMBASE, and Cochrane Library for studies through May 2020, and ultimately included 11 articles. The optimal goal of a truly balanced spine is to maintain the head over the femoral heads. When spinal imbalance occurs, the human body reacts through various compensatory mechanisms to maintain the head over the pelvis and to retain a horizontal gaze. Historically, deformity correction has focused on correcting scoliosis and preventing scoliotic curve progression. Following substantial correction of a spinal deformity, reciprocal changes take place in the flexible segments proximal and distal to the area of correction. Restoration of lumbar lordosis following surgery to correct a thoracolumbar deformity induces reciprocal changes in T1 slope, cervical lordosis, pelvic shift, and lower extremity parameters. Patients with cervical kyphosis exhibit different patterns of reciprocal changes depending on whether they have head-balanced or trunk-balanced kyphosis. These reciprocal changes should be considered to in order to prevent secondary spine disorders. We emphasize the importance of evaluating the global spinal alignment to assess postoperative changes.

13.
J Clin Med ; 10(18)2021 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-34575160

RESUMEN

The comparative efficacy and safety between lenvatinib and hepatic artery infusion chemotherapy (HAIC) in patients with unresectable hepatocellular carcinoma (HCC) is still unclear. This multicenter historical cohort study enrolled 244 patients who were treated with HAIC (n = 173) or lenvatinib (n = 71) between 2012 and 2020. Propensity score matching (PSM) was performed, and 52 patients were selected per group. Clinical outcomes and safety were compared. Objective response rate (ORR) was not different between the two groups (26.0% vs. 23.1%, p = 0.736). Before PSM, the HAIC group had a higher proportion of Child-Pugh B and portal vein tumor, whereas the lenvatinib group had more patients with extrahepatic metastases, which was adjusted after PSM. There were no differences in progression-free survival (PFS) and overall survival (OS) after PSM (HAIC vs. lenvatinib, median PFS, 3.6 vs. 4.0 months, p = 0.706; median OS 10.8 vs. 7.9 months, p = 0.106). Multivariate Cox-regression showed that alpha-fetoprotein ≤1000 ng/mL was only an associated factor for OS after PSM in all patients (hazard ratio = 0.421, p = 0.011). Subgroup analysis for patients with a high tumor burden beyond the REFLECT eligibility criteria revealed that the HAIC group (n = 29) had a significantly longer OS than did the lenvatinib group (n = 30) (10.0 vs. 5.4 months, p = 0.004). More patients in the HAIC group achieved better liver function than those in the lenvatinib group at the time of best responses. There was no difference in the incidence of grade 3 and 4 adverse events between the two groups. Therefore, lenvatinib is comparable to HAIC in terms of ORR and OS in unresectable HCC meeting REFLECT eligibility criteria.

14.
ACS Appl Mater Interfaces ; 13(25): 29602-29611, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-34138554

RESUMEN

Sunlight-based desalination is one of the most environment-friendly, low-cost methods for obtaining freshwater on the planet. We implemented a biomimetic three-dimensional (3D) solar evaporator, improved by a solar-induced air-flow updraft. A carbon-coated polyvinyl alcohol (PVA) foam allowed us to achieve perfect absorption of ultrabroadband sunlight and continuously provide water to tall 3D structures. Integrating the convection flower (Amorphophallus titanum) and solar chimney structure, we proposed a bio-inspired 3D solar evaporator system that generates an updraft airflow. This updraft replaces saturated vapor between neighboring PVA foams with dry air, resulting in a significant increase in the effectiveness of dry air-water contact interfaces. Under the 1 sun condition (1 kW m-2), we achieve a high solar-vapor conversion efficiency of 95.9%.

15.
Micromachines (Basel) ; 12(3)2021 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-33808738

RESUMEN

In this study, we analyzed the threshold voltage shift characteristics of bottom-gate amorphous indium-gallium-zinc-oxide (IGZO) thin-film transistors (TFTs) under a wide range of positive stress voltages. We investigated four mechanisms: electron trapping at the gate insulator layer by a vertical electric field, electron trapping at the drain-side GI layer by hot-carrier injection, hole trapping at the source-side etch-stop layer by impact ionization, and donor-like state creation in the drain-side IGZO layer by a lateral electric field. To accurately analyze each mechanism, the local threshold voltages of the source and drain sides were measured by forward and reverse read-out. By using contour maps of the threshold voltage shift, we investigated which mechanism was dominant in various gate and drain stress voltage pairs. In addition, we investigated the effect of the oxygen content of the IGZO layer on the positive stress-induced threshold voltage shift. For oxygen-rich devices and oxygen-poor devices, the threshold voltage shift as well as the change in the density of states were analyzed.

16.
Clin Lab ; 67(2)2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33616343

RESUMEN

BACKGROUND: The American Thyroid Association suggested selective performance of the thyroid function test (TFT) in pregnant women with risk factors such as age over 30 years. We evaluated the limited indication of TFT based on age by analyzing our institution's retrospective data about TFT in pregnant women. METHODS: We retrospectively analyzed the results of thyroid stimulating hormone (TSH) and free thyroxine (FT4) with the antithyroid autoantibody test using the Cobas 8000 e801 module (Roche Diagnostics, Mannheim, Germany) performed during the first trimester of pregnancy. Data were analyzed and compared between subjects younger or older than 30 years. RESULTS: The mean values of TSH and FT4 did not show any significant differences according to age. Also, the two groups had similar prevalence of overt/subclinical hypothyroidism. It was analyzed that over 20% of overt hypothyroidism could be missed by applying age-based screening. CONCLUSIONS: Selective screening according to age (> 30 years) can miss a considerable number of pregnant women with hypothyroidism. Considering the value of appropriate screening and treatment in pregnant women with hypothyroidism, universal screening is necessary rather than selective screening considering the age of pregnant women.


Asunto(s)
Complicaciones del Embarazo , Pruebas de Función de la Tiroides , Adulto , Asia , Femenino , Alemania , Humanos , Edad Materna , Embarazo , Complicaciones del Embarazo/diagnóstico , Complicaciones del Embarazo/epidemiología , Primer Trimestre del Embarazo , Valores de Referencia , Estudios Retrospectivos , Tirotropina , Tiroxina
17.
J Phys Act Health ; 18(2): 165-174, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33429358

RESUMEN

BACKGROUND: The examination of the longitudinal effect of leisure-time physical activity (LTPA) on mental well-being is important, but previous studies have typically been limited by their use of a cross-sectional approach. This study empirically examined how LTPA intensity was associated with changes in distinct functions of mental well-being (eg, emotional, psychological, social) over time, and vice versa. METHODS: Parallel latent growth curve modeling in combination with propensity score matching analysis was conducted. Data were derived from a sample of adults from the Midlife in the United States (MIDUS) study. RESULTS: The results showed that the initial level of moderate LTPA at the baseline was associated with growth in psychological and social functioning over time, and vice versa. However, vigorous LTPA at the baseline was related only to growth in emotional functioning over time. CONCLUSION: The longitudinal association between LTPA and mental well-being had different matching mechanisms for LTPA intensities and their relation to distinct functioning for mental well-being. The findings contribute to an enhanced understanding of LTPA's longitudinal effect on mental well-being.


Asunto(s)
Ejercicio Físico , Actividades Recreativas , Adulto , Emociones , Humanos , Salud Mental , Actividad Motora
18.
Neurospine ; 17(3): 497-504, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33022154

RESUMEN

When spinal imbalance occurs, the human body reacts through various compensatory mechanisms to maintain the head over the pelvis and to retain a horizontal gaze. These compensations occur through mobile spine segments as well as pelvic tilt and lower extremities. The purpose of this review was to understand the surgical impact on global sagittal alignment and health-related quality of life (HRQoL) following cervical kyphosis correction surgery. The cervical kyphosis correction surgery induces reciprocal changes in craniocervical and thoracolumbar alignment. Successful cervical deformity correction needs to focus not only on restoring proper cervical lordosis, but also on achieving global balance of the cervical spine with other parts of the spine. The goal of the surgery is to achieve occiputtrunk (OT) concordance (the center of gravity-C7 sagittal vertical axis < 30 mm) and cervical sagittal balance. Once OT-concordance is achieved, subsequent thoracolumbar alignment changes occur as needed to harmonize global spinal alignment. Reciprocal changes after surgery exhibit different patterns depending on whether patients have compensation ability in their thoracolumbar spine or not. C2-7 sagittal vertical axis and sagittal morphotype of the cervical kyphosis are correlated with HRQoL. Changes in cervical lordosis minus T1 slope correlate to HRQoL improvements.

19.
Langmuir ; 36(42): 12494-12503, 2020 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-33049134

RESUMEN

Solar steam generation is a promising solar energy harvesting technology to address the global clean energy and water deficiency cost-effectively. In this work, we present a compact plasmonic nanostructure-nanoparticle composite based on haze/GO-rGO/Au enabling multiple purposes such as broadband solar absorption, solar steam generation, and solar desalination. The graphene oxide-reduced GO (GO-rGO) combination allows broadband optical absorption, and the presence of 5 nm Au nanoparticles creates high-density localized hotspots for enhanced photothermal effect as evidenced through Raman signal enhancement studies. Anodized aluminum oxide-based haze nanostructures provide maximum light interaction volume through multiple nanogaps and porosity through vertically aligned nanowires of 20-26 nm width and 5-10 µm depth for water channelization. The haze sample coated with GO-rGO/Au shows high solar absorbance of 92.5% over the 300-2500 nm wavelength range covering the whole solar spectrum (ultraviolet-visible-near-infrared). We have achieved 50 and 71.1% of solar-to-thermal conversion efficiencies in a single-layer microscale sample for saline and freshwater, respectively, with a maximum surface temperature of 95.7 °C. The efficiencies increase to 64 and 77% for two layers of the sample at 5 suns (5 kW m-2) illumination.

20.
ACS Appl Mater Interfaces ; 12(9): 10626-10636, 2020 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-32030970

RESUMEN

A newly developed nanopatterned broadband antireflective (AR) coating was fabricated on the front side of a glass/indium tin oxide/perovskite solar cell (PSC) by depositing a single interference layer onto a two-dimensional (2D)-patterned moth-eye-like nanostructure. The optimized developed AR nanostructure was simulated in a finite-difference time domain analysis. To realize the simulated developed AR nanostructure, we controlled the SiO2 moth-eye structure with various diameters and heights and a MgF2 single layer with varying thicknesses by sequentially performing nanosphere lithography, reactive ion etching, and electron-beam evaporation. Optimization of the developed AR nanostructure, which has a 100 nm-thick MgF2 film coated onto the SiO2 moth-eye-like nanostructure (diameter 165 nm and height 400 nm), minimizes the reflection loss throughout the visible range. As a result, the short-circuit current density (JSC) of the newly AR-coated PSC increases by 11.80%, while the open-circuit voltage (VOC) remains nearly constant. Therefore, the power conversion efficiency of the newly developed AR-decorated PSC increases by 12.50%, from 18.21% for a control sample to 20.48% for the optimum AR-coated sample. These results indicate that the newly developed MgF2/SiO2 AR nanostructure can provide an advanced platform technology that reduces the Fresnel loss and therefore increases the possibility of the commercialization of glass-based PSCs.

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