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1.
PLoS One ; 19(5): e0301035, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38748645

RESUMO

The study aimed to investigate the survival rate of patients with dementia according to their level of physical activity and body mass index (BMI). A total of 5,789 patients with dementia were retrieved from the 2009-2015 National Health Insurance Sharing Service databases. Survival analysis was used to calculate the hazard ratio (HR) for physical activity and BMI. The study sample primarily comprised older adults (65-84 years old, 83.81%) and female (n = 3,865, 66.76%). Participants who engaged in physical activity had a lower mortality risk (HR = 0.91, p = 0.02). Compared to the underweight group, patients with dementia who had normal weight (HR = 0.86, p = 0.01), obesity (HR = 0.85, p = 0.03) and more than severe obesity (HR = 0.72, p = 0.02) demonstrated a lower mortality risk. This study emphasizes the significance of avoiding underweight and engaging in physical activity to reducing mortality risk in patients with dementia, highlighting the necessity for effective interventions.


Assuntos
Índice de Massa Corporal , Demência , Exercício Físico , Humanos , Feminino , Idoso , Demência/mortalidade , Demência/epidemiologia , Masculino , Idoso de 80 Anos ou mais , Programas Nacionais de Saúde , Bases de Dados Factuais , Obesidade/mortalidade , Magreza/mortalidade
2.
Am J Occup Ther ; 78(2)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38393990

RESUMO

IMPORTANCE: Although cross-sectional studies have reported the relationships among performance of activities of daily living (ADLs), income satisfaction, and health satisfaction, longitudinal associations in stroke survivors remain unclear. OBJECTIVE: To examine the effects of ADL function and income satisfaction on health satisfaction over time in stroke survivors. DESIGN: Retrospective longitudinal study designs with latent growth curve models (LGMs) to control for time-varying and time-invariant covariates. SETTING: Community. PARTICIPANTS: A total of 198 stroke survivors. OUTCOMES AND MEASURES: Self-reported ADL performance, income satisfaction, and health satisfaction. RESULTS: The average age of participants was 70.68 yr (SD = 8.09; 107 men, 91 women). Each LGM showed that an increase in ADL score (standardized ß = 0.116∼0.296, all ps < .05) and income satisfaction (standardized ß = 0.513∼0.726, all ps < .001) positively predicted health satisfaction over time, even after controlling for time-varying annual income, demographics, and behavioral characteristics. The fit results of all LGMs were within the acceptable range: χ2(47) = 66.378, p = .0327; χ2(47) = 57.742, p = .1355; root-mean-square error of approximation, <0.08; comparative fit index and Tucker-Lewis index, >0.90; standardized root-mean-square residual, <0.05. CONCLUSIONS AND RELEVANCE: Because ADLs are significant modifiable health satisfaction factors, occupational therapy practitioners would need to focus more closely on ADL training in clinical settings. Furthermore, referring those clients to appropriate vocational rehabilitation to improve their income satisfaction would be necessary. Plain-Language Summary: This study recognizes the unique challenges and opportunities that arise when stroke survivors are preparing to return to their communities by emphasizing the significance of ADL training and income satisfaction during this stage of recovery. The study suggests that the therapeutic use of ADL training and income satisfaction could increase health satisfaction for stroke survivors. Therefore, comprehensive ADL training, as an occupational therapy intervention, could be crucial for stroke survivors who are preparing to return to their community from a clinical setting. Furthermore, connecting with vocational rehabilitation could also be important for improving income satisfaction for stroke survivors who are preparing to return to a community.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Masculino , Humanos , Feminino , Atividades Cotidianas , Estudos Transversais , Estudos Retrospectivos , Estudos Longitudinais , Estado Funcional , Sobreviventes , Satisfação Pessoal
3.
Eval Health Prof ; : 1632787231177473, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37222735

RESUMO

We aimed to calculate disability-adjusted life expectancy (DALE) for Korean older adults based on their sex, educational attainment, and residential region across their cognitive status. We included 3,854 participants (aged 65-91 years) from the Korean Longitudinal Study of Aging's seventh survey data. The participant's cognitive function status (normal, moderately impaired, or severely impaired) was determined based on cognitive examination and physical function independence, which was used to calculate their DALE. Females with normal cognition had higher DALE (7.60 years, Standard Deviation (SD) = 3.88) than males (6.76, SD = 3.40); however, both sexes had comparable DALE for cognitive impairment. In contrast, the DALE values increased with higher educational achievements. Regarding residential areas, the DALE value for participants with normal cognition and moderate impairment was the highest among urban dwellers, while DALE for participants with severely impaired cognitive function was highest among rural dwellers; however, there were no statistically significant differences based on residential conditions. Our findings suggest that demographic characteristics should be considered when developing health policies and treatment strategies to meet the needs of the aging population in Korea.

4.
Int J Aging Hum Dev ; 97(4): 496-512, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36560911

RESUMO

This study investigates the psychometric properties of the Meaningful Activity Participation Assessment-Meaning (MAPA-M) scale using the Rasch measurement model. For the psychometric properties of MAPA-M, principal component analysis, Rasch analysis, and differential item functioning analysis were conducted. Participants in this study were 480 older adults from the USC Well Elderly 2 study, recruited from 21 locations in the Los Angeles metropolitan area. There were eight items with DIF, but they were accepted because they assumed unidimensionality and showed good person invariance. The 25 items assuming unidimensionality of MAPA-M had values between 0.6 and 1.4 in infit and Outfit MnSq, and all ZSTD values were less than 2.0. The 25 items demonstrated a conceptual item-difficulty hierarchy. The person strata value was 2.68, which is equivalent to a reliability index value of .76. The findings indicate that the revised scale can accurately and reliably measure meaningful activities by older adults.


Assuntos
Psicometria , Humanos , Idoso , Reprodutibilidade dos Testes , Inquéritos e Questionários
5.
OTJR (Thorofare N J) ; 43(2): 202-210, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36377234

RESUMO

Older adults gradually decrease their independence with activities of daily living (ADL) due to aging. The coronavirus disease-19 (COVID-19), the recent pandemic, can accelerate the decline in functions, such as ADL. This study aimed to examine whether there is an association between positive COVID-19 results and decreased independence with ADL in older adults. Data for a total of 3,118 older adults were extracted from the 2020 National Health and Aging Trends Study-COVID-19. A total of 71 (2.29%) participants presented with positive COVID-19 tests. There was a significant association between a positive COVID-19 result and decreased independence with ADL (relative risk [RR] = 1.47, 95% confidence interval [CI] = [1.11, 1.96], p = .0079). The study findings revealed that COVID-19 survivors had a high risk of decreased independence with ADL. These findings indicate that COVID-19 survivors have residual functional deficits and would need comprehensive health care services.


Assuntos
Atividades Cotidianas , COVID-19 , Humanos , Idoso , Envelhecimento
6.
Epidemiol Health ; 44: e2022095, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36317401

RESUMO

OBJECTIVES: This study aimed to investigate health-adjusted life expectancy (HALE) by demographic characteristics (sex, educational achievement, and residential area) according to the lifestyle classifications of the Yonsei Lifestyle Profile-BREF (YLP-BREF). METHODS: This study included 569 participants aged 55 years or older living in Korea. The YLP-BREF domains were physical activity, activity participation, and nutrition. RESULTS: Females had a longer HALE (mean±standard deviation, 8.90±5.06 years) in the physical activity domain, while males had a longer HALE in the nutrition domain (9.44±5.91 years). People living in rural areas had longer HALE in physical activity (12.02±5.60 years), activity participation (8.58±4.21 years), and nutrition (11.33±6.43 years). There were no significant differences according to sex or residential area. High school graduates showed the longest HALE (physical activity: 10.38± 6.89; activity participation: 7.64±4.29; nutrition: 9.59±6.40 years). There was a significant difference in educational achievement. CONCLUSIONS: As people age, the demand for a healthy lifestyle increases. This study attempted to calculate HALE by demographic characteristics according to lifestyle. The results of this study will help inform future research directions for providing a healthy lifestyle.


Assuntos
Expectativa de Vida , Estilo de Vida , Feminino , Humanos , Masculino , Exercício Físico
7.
Artigo em Inglês | MEDLINE | ID: mdl-36011988

RESUMO

This study aims to develop a universal scale for comparing cognitive and physical functions among countries using health survey data from China, Korea, and Japan. This study used the data of 934 participants from the Korean Longitude Study of Aging, 2506 participants from the China Health and Retirement Longitude Study, and 178 participants from the Japanese Study of Aging and Retirement. Each physical and cognitive function item in the three countries has five key items. The anchoring method used the key items to link each cognitive and physical function of the three countries. We investigated the psychometric characteristics of the final item using the Rasch analysis. We extracted 13 items of 19 cognitive function items and 20 items out of 29 physical function items using the anchoring method and the Rasch analysis. The Rasch analysis showed good fit statistics for 13 cognitive function items and 20 physical function items. The measurement scale developed in this study will enable valid comparisons of older adults' cognitive and physical functions across these three countries.


Assuntos
Pessoas com Deficiência , Idoso , Inquéritos Epidemiológicos , Humanos , Japão , Psicometria/métodos , Reprodutibilidade dos Testes , República da Coreia , Inquéritos e Questionários
8.
OTJR (Thorofare N J) ; 42(4): 344-352, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35904347

RESUMO

Social participation is associated with cognitive function; however, their causal relationships have not been reported yet. This study was designed to examine the autoregressive effects and bidirectional causal relationship between social participation and cognitive function. In this secondary longitudinal data analysis, we enrolled 4,834 Korean adults. A cross-lagged panel model with fixed effects was used to examine the causal relationships between social participation and cognitive function. Both participation (unstandardized coefficient = .370, p < .001) and cognitive function (unstandardized coefficient = .151, p < .001) had positive autoregressive effects over time. Participation had a cross-lagged effect on cognitive function (unstandardized coefficient = .061, p < .001). However, the cross-lagged effects of cognitive function on participation were not statistically significant (unstandardized coefficient = .051, p = .312). Various health-care programs that promote social participation and improve cognitive function must be established. Additional studies are required to confirm the causal effects of cognitive function on participation.


Assuntos
Vida Independente , Participação Social , Adulto , Cognição , Humanos , Participação Social/psicologia
9.
Int J Methods Psychiatr Res ; 31(2): e1908, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35278012

RESUMO

OBJECTIVES: This study used the 2016 Korean Longitudinal Study on Aging to investigate the social, behavioural, and functional characteristics of community-dwelling South Korean adults with cognitive impairment. METHODS: Participants were classified as normal, moderate impairment, and severe impairment according to an algorithm that combined the Korean Mini-Mental State Examination score and the number of difficulties in performing instrumental activities of daily living. Selected characteristics included grip strength, depression, participation in exercise and social activities, and living in a rural, urban, or suburban community. RESULTS: Most (72.7%) participants were classified as having normal cognition, 20.1% were classified as moderate impairment, and 7.2% were classified as severe impairment. Regardless of sex, the differences in grip strength across the cognitive status classifications were statistically significant, except for the difference between moderate and severe cognitive impairment in males (p = 0.8477). Greater number of depressive symptoms and living in rural areas were associated with significantly higher odds for severe cognitive impairment. Participants with moderate (OR = 0.51) and severe (OR = 0.33) cognitive impairment were less likely to participate in social activities than those with normal cognition. CONCLUSIONS: The study findings revealed that social, behavioural, and functional characteristics are closely related to the cognitive status of community-dwelling adults in South Korea.


Assuntos
Disfunção Cognitiva , Vida Independente , Atividades Cotidianas , Cognição , Disfunção Cognitiva/epidemiologia , Humanos , Estudos Longitudinais , Masculino , República da Coreia/epidemiologia
10.
Arch Public Health ; 80(1): 81, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35287736

RESUMO

BACKGROUND: While divorce is a social determinant of health among married immigrants in Korea, its association with access to healthcare services is unclear. Given the rapid increase in the number of married immigrants in Korea, research is needed to improve minority groups' access to healthcare services. Here, we examined healthcare service utilization among married immigrants. METHODS: We retrieved 11,778 adults from the 2018 Korea National Multicultural Family Survey. We analyzed whether the sex of divorced immigrants is associated with healthcare access using multivariable logistic regression analysis. Further, we analyzed the association between divorce and access to healthcare services among married immigrants using propensity score matching methods. RESULTS: There were 691 (5.8%) divorced immigrants in the data set. The married male immigrants had no association between divorce status and healthcare access (adjusted odds ratio [OR] = 1.05, 95% confidence interval [CI] = 0.55-2.03, p = 0.8620). Divorced immigrants were less likely to receive healthcare services than married immigrants (adjusted OR = 1.42, 95% CI = 1.07-1.88). CONCLUSION: Our findings revealed that divorce increases the risk of limited access to healthcare services among married immigrants. Policymakers and healthcare providers should be aware of these potential disparities in this vulnerable minority population.

11.
J Aging Phys Act ; 30(5): 770-777, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34879330

RESUMO

This study examined the association between achieving the recommended physical activity level and quality of life after controlling for depression. Health information from adults aged 65 years and older, who had participated in the seventh 2018 Korea National Health and Nutrition Examination Survey, was used. Five covariate adjustment models were used to derive robust estimates of the association between physical activity practice levels, depression, and older adults' quality of life. A total of 1,336 older adults was extracted from the seventh 2018 Korea National Health and Nutrition Examination Survey, and 31% of the older adults achieved the recommended physical activity level, whereas 69% did not. We found that the achievement of physical activity practice levels is significantly associated with the quality of life of the older adults (ß = 0.024-0.031, all p < .05). Our results could be used for advocating for welfare policy changes that promote physical activity to prepare for the upcoming super-aging society.


Assuntos
Vida Independente , Qualidade de Vida , Idoso , Estudos Transversais , Depressão , Exercício Físico , Humanos , Inquéritos Nutricionais , Pontuação de Propensão
12.
Inquiry ; 58: 469580211062451, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34898332

RESUMO

BACKGROUND: Cross-national studies are an emerging research area in public health. Specifically, cross-national health comparisons are important for understanding the factors driving the success or failure of public health policies. Therefore, this study systematically analyzed studies that compared health status (physical health and cognition) of the older adults using national panel data for three East Asian countries-China, Japan, and Korea. METHODS: Google Scholar and PubMed were used for the literature search. The search strategy targeted papers published between 2005 and 2020, yielding a total of 2690 papers, of which seven were selected for the review. The Center for Evidence-Based Medicine (CEBM) criteria was used to assess study design quality. The risk of bias for non-randomized studies (RoBANS) tool, a quality assessment tool developed in Korea to evaluate non-randomized interventional studies, measured risk of bias. RESULTS: Of the seven included papers, two studies performed cognitive comparisons, four studies performed physical health comparisons, and one study compared both cognition and physical health. The studies selected for this study by CEBM criteria included four prospective cohort studies (Level 2B) and three expert opinions without explicit critical appraisal (Level 5). Risk of bias using the RoBANS tool found a risk of confounding variables in four out of seven papers. Finally, measurement items of cognitive and physical health differed across all three countries' panel surveys. CONCLUSION: These results suggest that in order to compare East Asian health policies according to the aging society, it is necessary to develop consistent cognitive and physical health evaluation tools in the future.


Assuntos
Cognição , Nível de Saúde , Idoso , China , Humanos , Japão , Estudos Prospectivos
13.
Biochem Biophys Res Commun ; 515(1): 183-189, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31133378

RESUMO

Heterotypic cell-cell interaction between cancer cells and pancreatic stellate cells (PSCs) within tumor microenvironment is considered as a key mechanism for epithelial-mesenchymal transition (EMT) that triggers disease progression and chemoresistance in pancreatic ductal adenocarcinoma (PDAC). Hence, PSCs should be incorporated into in vitro co-culture models to maximize clinical relevance of data obtained using these models. In this study, we developed hetero-type spheroids of pancreatic cancer cells (ductal carcinoma cells PANC-1 and primacy sarcomatoid adenocarcinoma 36473 cells) and PSCs. Effect of PSC co-culture on the formation and growth of multicellular spheroids was cell-line dependent in that growth stimulation effect appeared in PANC-1/PSC spheroids, but not in 36473/PSC spheroids. Spatial distribution of PSCs within spheroids was also cell-line dependent. It was either confined to the center region (PANC-1) or evenly distributed (36473). Changes in expression levels of E-cadherin and vimentin revealed EMT induction in PANC-1/PSC hetero-type spheroids, but not in 36473/PSC spheroids. Gemcitabine sensitivity was increased partially by PSC co-culture. However, PSCs showed relative resistance to gemcitabine compared to PANC-1 cells in PANC-1/PSC spheroids. Overall, our hetero-type spheroid model can be used to study cancer-stroma interaction and their mechanism and evaluate anticancer drug activity. We demonstrated that stromal effect by PSC co-culture might be cellular context dependent with regard to growth stimulation and EMT induction. Hence, anti-stromal therapy should take these differences into consideration.


Assuntos
Carcinoma Ductal Pancreático/metabolismo , Comunicação Celular , Neoplasias Pancreáticas/metabolismo , Células Estreladas do Pâncreas/metabolismo , Antimetabólitos Antineoplásicos/farmacologia , Caderinas/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Neoplasias Pancreáticas/patologia , Células Estreladas do Pâncreas/citologia , Esferoides Celulares/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Vimentina/metabolismo , Gencitabina
14.
J Nanosci Nanotechnol ; 19(2): 1048-1051, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30360198

RESUMO

We studied the optical sensing properties of ZnO nanoparticles prepared by spray pyrolysis. To investigate their optical sensing performance, we incubated peptides on ZnO nanoparticles. The photoluminescence (PL) peak intensity of peptides on the ZnO nanoparticles was higher than that of peptides on the ZnO film or on the glass plate. This observed PL enhancement is attributed to the optical confinement of ZnO nanoparticles. The low-temperature spectra displayed a strong exciton emission peak with multiple sidebands, attributed to the bound exciton and its longitudinal optical phonon sidebands. The strong exciton emission is thought to be the combined effect of optical confinement due to the nanoparticle geometry, reduction of defect emission by thermal annealing, and reduction of non-radiative relaxation at low temperatures.

15.
J Nanosci Nanotechnol ; 18(9): 5970-5975, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29677726

RESUMO

Color changes controlled by electronic energies have been studied for many years in order to fabricate energy-efficient smart windows. Reduction and oxidization of nickel oxide under the appropriate voltage can change the color of a window. For a superior nickel oxide (NiO) electrochromic device (ECD), it is important to control the chemical and physical characteristics of the surface. In this study, we applied polystyrene bead templates to nickel oxide films to fabricate a honeycomb-structured electrochromic (EC) layer. We synthesized uniform polystyrene beads using the chemical wet method and placed them on substrates to create honeycomb-structured NiO films. Then, the EC characteristics of the nickel oxide films with a honeycomb structure were evaluated with UV-Visible and cyclic voltammetry. FE-SEM and AFM were used to measure the morphologies of the nanostructures and the efficiencies of the redox reactions related to the specific surface area.

16.
J Nanosci Nanotechnol ; 16(5): 4875-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27483838

RESUMO

The multiple exciton generation characteristics of quantum dots have been expected to enhance the performance of photochemical solar cells. In previous work, we first introduced Si quantum dot for sensitized solar cells. The Si quantum dots were fabricated by multi-hollow discharge plasma chemical vapor deposition, and were characterized optically and morphologically. The Si quantum dot-sensitized solar cells had poor performance due to significant electron loss by charge recombination. Although the large Si particle size resulted in the exposure of a large TiO2 surface area, there was a limit to ho much the particle size could be decreased due to the reduced absorbance of small particles. Therefore, this work focused on decreasing the internal impedance to improve charge transfer. TiO2 was electronically modified by doping with vanadium, which can improve electron transfer in the TiO2 network, and which is stable in the redox electrolyte. Photogenerated electrons can more easily arrive at the conductive electrode due to the decreased internal impedance. The dark photovoltaic properties confirmed the reduction of charge recombination, and the photon-to-current conversion efficiency reflected the improved electron transfer. Impedance analysis confirmed a decrease in internal impedance and an increased electron lifetime. Consequently, these improvements by vanadium doping enhanced the overall performance of Si quantum dot-sensitized solar cells.

17.
J Nanosci Nanotechnol ; 16(5): 4886-92, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27483840

RESUMO

We developed a technique for forming textured aluminum-doped zinc oxide (ZnO:Al) transparent conductive oxide (TCO) films on glass substrates, which were etched using a mixture of hydrofluoric (HF) and hydrochloric (HCl) acids. The etching depth and surface roughness increased with an increase in the HF content and the etching time. The HF-based residues produced insoluble hexafluorosilicate anion- and oxide impurity-based semipermeable films, which reduced the etching rate. Using a small amount of HCl dissolved the Ca compounds, helping to fragment the semipermeable film. This formed random, complex structures on the glass substrates. The angled deposition of three layers of ZnO:Al led to the synthesis of multiscaled ZnO:Al textures on the glass substrates. The proposed approach resulted in textured ZnO:Al TCO films that exhibited high transmittance (-80%) and high haze (> 40%) values over wavelengths of 400-1000 nm, as well as low sheet resistances (< 18 Ω/sq)..Si tandem solar cells based on the ZnO:Al textured TCO films exhibited photocurrents and cell efficiencies that were 40% higher than those of cells with conventional TCO films.

18.
J Nanosci Nanotechnol ; 16(5): 4968-72, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27483853

RESUMO

In present work, the effects of the heat treatment on the structural, optical, and thermochromic properties of vanadium oxide films were investigated. Vanadium dioxide (VO2) thin films were deposited on glass substrate by reactive pulsed DC magnetron sputtering from a vanadium metal target in mixture atmosphere of argon and oxygen gas. Various heat treatment conditions were applied in order to evaluate their influence on the crystal phases formed, surface morphology, and optical properties. The films were characterized by an X-ray diffraction (XRD) in order to investigate the crystal structure and identify the phase change as post-annealing temperature of 500-600 degrees C for 5 minutes. Surface conditions of the obtained VO2(M) films were analyzed by field emission scanning electron microscopy (FE-SEM) and the semiconductor-metal transition (SMT) characteristics of the VO2 films were evaluate by optical spectrophotometry in the UV-VIS-NIR, controlling temperature of the films.

19.
J Nanosci Nanotechnol ; 16(5): 5024-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27483864

RESUMO

Highly structured interfaces are very desirable in organic photovoltaic solar cells (OPVs), in order to enhance power conversion efficiency (PCE) by decreasing of the transport path for excited charge carriers in the absorber and increasing the optical path length for photon absorption. Many complicated, high-cost lithographic methods have been attempted to modify the surface of the absorber or substrate. However, solution-based colloidal-lithography processes are scalable and cost-effective, but generally result in non-uniform structured surfaces. In this report, we demonstrated an optimized silica-templated colloidal lithographical approach to create a well-defined and controlled transparent ITO layer for enhancing power conversion efficiency (PCE). Additionally, morphological effects of the patterned ITO on optical properties and PCE were analyzed in detail.

20.
Materials (Basel) ; 9(7)2016 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-28773679

RESUMO

This paper presents the preparation of high-quality vanadium dioxide (VO2) thermochromic thin films with enhanced visible transmittance (Tvis) via radio frequency (RF) sputtering and plasma enhanced chemical vapor deposition (PECVD). VO2 thin films with high Tvis and excellent optical switching efficiency (Eos) were successfully prepared by employing SiO2 as a passivation layer. After SiO2 deposition, the roughness of the films was decreased 2-fold and a denser structure was formed. These morphological changes corresponded to the results of optical characterization including the haze, reflectance and absorption spectra. In spite of SiO2 coating, the phase transition temperature (Tc) of the prepared films was not affected. Compared with pristine VO2, the total layer thickness after SiO2 coating was 160 nm, which is an increase of 80 nm. Despite the thickness change, the VO2 thin films showed a higher Tvis value (λ 650 nm, 58%) compared with the pristine samples (λ 650 nm, 43%). This enhancement of Tvis while maintaining high Eos is meaningful for VO2-based smart window applications.

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