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1.
Small ; : e2402903, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38923389

ABSTRACT

Integrated electrochromic devices powered by photovoltaic cells have evoked a lot of interest due to their promising commercial prospects. However, their application has been restricted by the voltage adaption between the self-powered voltage and the color-changing threshold voltage (Vt). Herein, a strategy of bidirectional voltage regulating is proposed to develop a novel stand-alone integrated photovoltachromic device (I-PVCD), which integrates perovskite/organic tandem solar cells (P/O-TSCs) to drive color-changing process of conjugated poly(3-hexylthiophene) (P3HT) films. To lower the driving-voltage of electrochromic layer, C60 is introduced to decrease the onset oxidation potential of P3HT film, and thus leading to a reduced Vt of 0.70 V benefiting from the enhanced highest occupied molecular orbital level and decreased charge transfer resistance from 67.46 to 49.89 Ω. Simultaneously, PBDB-T is utilized as the hole transport layer in the interconnecting layer of CsPbI2Br/PTB7-Th:IEICO-4F P/O-TSC to improve its open-circuit voltage (Voc) to 1.85 V. Under their synergetic merits, a I-PVCD with a wider self-adaptive voltage range is achieved. This device can undergo fast and reversible chromic transition from beautiful magenta to transparent only under the solar radiation, and demonstrates a coloration efficiency of 351.90 cm2 C-1 and a switching time of 2 s besides its excellent operating reliability.

2.
BMJ Open ; 14(3): e082548, 2024 Mar 11.
Article in English | MEDLINE | ID: mdl-38471688

ABSTRACT

OBJECTIVES: In view of the serious ageing of China's population and the low desire of elderly people to purchase institutionalised elderly care services, we explored the willingness of Chinese elderly people to purchase institutionalised elderly care services and its influencing factors. DESIGN: This was a cross-sectional study. Three multivariate logistic regression analysis models of the willingness of elderly people to purchase institutionalised elderly care services were established (model 1: 'reluctance - willingness'; model 2: 'reluctance - hesitation'; and model 3: 'hesitation - willingness') to explore the factors that influence elderly people's willingness to purchase institutionalised elderly care services. SETTING: This study was based on the 2022 Psychology and Behaviour Investigation of Chinese Residents database. PARTICIPANTS: Research data from 4123 older adults who met the requirements of this study were screened from the database. RESULTS: Of the 4123 respondents, roughly equal numbers had negative and positive attitudes towards purchasing institutionalised senior care services (1125, 27.3% vs 1079, 26.2%, respectively), and 1919 (46.5%) had hesitant attitudes. The analysis of model 1 showed that medical insurance participation, the number of children and siblings, chronic diseases and per capita monthly household income had an influential effect on the willingness of elderly people to purchase institutional care. In model 2, we found that factors such as per capita monthly household income and anxiety led to hesitancy among older adults to purchase institutionalised senior care services. In model 3, we further found that social support and health literacy led to a shift from hesitation to willingness to purchase institutionalised elderly care services. CONCLUSION: The number of children, number of siblings, per capita monthly income of the family, medical insurance participation, health status, health literacy and social support were found to be the main factors influencing the purchase of institutionalised care by elderly individuals.


Subject(s)
Aging , Income , Child , Humans , Aged , Cross-Sectional Studies , Health Status , China , Surveys and Questionnaires
3.
JMIR Mhealth Uhealth ; 12: e52573, 2024 Jan 26.
Article in English | MEDLINE | ID: mdl-38277215

ABSTRACT

BACKGROUND: Against the backdrop of globalization, China remains one of the most heavily burdened countries in Asia with regard to AIDS. However, many high-risk groups and patients affected by AIDS may be less likely to actively seek care from medical institutions because of fear of experiencing shame or discrimination. Mobile apps provide a promising avenue for supporting the prevention, diagnosis, and treatment of AIDS. However, a comprehensive systematic evaluation of these mobile apps' functionality and quality has not been conducted yet. OBJECTIVE: This study aims to identify the available mobile apps for AIDS in China, assess and discuss the functional features and quality of these Chinese AIDS mobile apps, and offer decision support for patients and clinical practitioners in accessing high-quality AIDS mobile apps. Furthermore, based on the evaluation results, recommendations for improvement will be provided. METHODS: A systematic search was conducted on the Qimai app data platform, the Aladdin WeChat applet data platform, and WeChat to identify mobile apps related to AIDS. A snowball sampling method was used to supplement the potentially overlooked apps. The selected mobile apps underwent a rigorous screening process based on unified criteria. Subsequently, assessments were independently undertaken by 3 separate researchers and 2 patients with HIV, using both the Mobile App Rating Scale (MARS) and the User Mobile App Rating Scale (uMARS). Quantitative interpretations of the data were facilitated by the MedCalc statistical software (version 20.217, MedCalc Software). RESULTS: A total of 2901 AIDS mobile apps were included in the study, with 2897 identified through information retrieval and an additional 4 added via snowball sampling. After a rigorous selection process, 21 apps were determined to be usable. Among them, the Hong Feng Wan app achieved the highest combined average score, calculated based on the MARS (3.96, SD 0.33) and uMARS (4.47, SD 0.26). Overall, there was no significant correlation between MARS and uMARS (rapp quality total score=0.41; P=.07; rsubjective quality=0.39; P=.08). A notable issue was the widespread lack of user privacy protection, with only 24% (5/21) of the apps offering this feature. CONCLUSIONS: The number of available Chinese AIDS mobile apps is limited, with WeChat applets dominating the market. Nonetheless, the performance of WeChat mini-apps is generally inferior to that of independent apps, and there may be significant discrepancies between assessments conducted by researchers and those provided by genuine end users, emphasizing the necessity of involving real users in the development and evaluation of HIV mobile apps. In addition, developers of these Chinese HIV mobile apps need to devote attention to improving privacy protection mechanisms, in addition to considering the evaluations of researchers and real users. This will help attract more users and increase user loyalty.


Subject(s)
Acquired Immunodeficiency Syndrome , Mobile Applications , Humans , China
4.
J Gerontol Nurs ; 49(11): 25-32, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37906042

ABSTRACT

There is a shortage of personnel to provide care for older adults with dementia, and traditional teaching methods could be improved. The teaching method used in the Care for Older Adults With Dementia course is mainly theoretical, lacking real-life care scenarios and practical procedural training. In the current study, we developed a virtual reality (VR) teaching system and designed a randomized controlled trial aimed at testing the availability of the VR-assisted teaching system, filling the gap in teaching through care scenarios, enabling students majoring in intelligent health and oldage care service management to have a more positive attitude toward learning, and improving students' knowledge and course satisfaction. This study showed that the developed VR system can meet the initial needs of daily teaching, help students have a more positive attitude toward learning, and improve their academic performance and course satisfaction. [Journal of Gerontological Nursing, 49(11), 25-32.].


Subject(s)
Dementia , Geriatric Nursing , Virtual Reality , Humans , Aged , Students , Clinical Competence , Dementia/therapy
5.
J Telemed Telecare ; 29(9): 731-746, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37477425

ABSTRACT

BACKGROUND: With the continuous development of the Internet and information technology, telemedicine has gradually become a popular medical model, which has always attracted much attention. Especially in recent years, research has shown a rapid increase in the use of telemedicine due to the impact of COVID-19. We have conducted a scientific metrological analysis of telemedicine to identify its hot spots and frontiers and promote cooperation and development. METHODS: We retrieved 19,171 articles related to telemedicine published from 1971 to 2022 in the Web of Science (WOS) database. Then, we conducted co-author network analysis (author, institution, country), co-citation analysis (author, journal, literature) and burst analysis (thematic trends and frontier topics). RESULTS: The number of publications has been on the rise since 1993 and began to rise rapidly in 1997. Influenced by the COVID-19 pandemic, the number of articles doubled in 2020 compared to the prior year. The United States produced the greatest number of articles (43.4%). Although studies in Greece are fewer and more recent, the country is demonstrating tremendous development potential in this field and is an active contributor to telemedicine research. The main research topics identified include the application, system and services of telemedicine; the application of telemedicine in providing medical services to rural and remote areas where medical resources are scarce; the quality control of medical images in telemedicine; the application of telemedicine in chronic disease care; and the comparison of in-person medical care and telemedicine. Emerging topics include the application and impact of telemedicine during the COVID-19 pandemic. CONCLUSION: The main telemedicine research fields over the past 52 years are identified, the meanings of analyses results are discussed, and emerging trends are highlighted.


Subject(s)
COVID-19 , Telemedicine , Humans , United States , Bibliometrics , Pandemics , COVID-19/epidemiology , Publications
6.
Nurs Open ; 10(9): 6045-6057, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37365734

ABSTRACT

AIM: This meta-analysis systematically reviewed and identified the effects of WeChat-based continuous care (WCC) interventions on various outcomes in cancer patients. DESIGN: Systematic review and meta-analysis. METHODS: In this study, outcome measures included somatic function, anxiety, depression, social function, and cognitive function. The standardized mean differences and 95% CIs of pooled effect sizes were calculated using fixed- and random-effects models. NFail-safe and Begg's tests were performed to evaluate publication bias, and sensitivity analysis was performed to evaluate the robustness of the meta-analysis results. RESULTS: The meta-analysis included 18 RCTs of moderate quality. WCC interventions significantly improved somatic function, depression, anxiety, social function, and cognitive function in cancer patients. There was no significant publication bias, and the sensitivity analysis indicated robust results. PATIENT OR PUBLIC CONTRIBUTION: WCC interventions improved depression, anxiety, social function, and cognitive function in cancer patients.

7.
Health Serv Insights ; 15: 11786329221134352, 2022.
Article in English | MEDLINE | ID: mdl-36330309

ABSTRACT

Background: While the community health service system was initially established in rural areas of mainland China, the utilization of community health service resources by the rural elderly population is not clear. Methods: Cross-sectional studies on the utilization of community health services by the rural elderly population in mainland China published within the last 10 years were retrieved from the China National Knowledge Infrastructure (CNKI), Wan Fang, Medline and Web of Science (WOS) databases. The quality of the article was evaluated by the Critical Appraisal Skills Programme (CASP), and obstacles to the utilization of community health services by the rural elderly population were analyzed based on the Andersen model. Results: Twenty-four studies were analyzed, and 3 gaps were found. (i) The cognition of rural elderly residents does not match the current health security system. (ii) There is a gap between the supply of health service resources in rural communities and the health needs of the elderly residents in these areas. (iii) The health services provided by rural primary health service institutions are not targeted. Conclusions: In mainland China, the provision of community health services to the rural elderly population has improved significantly. However, several factors from the individual level to the system level lead to low levels of access and utilization. This finding means that under the leadership of the government, it is necessary to integrate the strength of multiple departments to cooperate in improving the welfare system, policy publicity, health education, financial support, system guarantees and resource exchange and sharing for the elderly population in rural areas and to jointly promote community health services for the elderly population in rural areas.

8.
Small Methods ; 6(10): e2200624, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36031396

ABSTRACT

All-inorganic CsPbI2 Br perovskite has attracted great attention due to the stable crystal structure and moisture resistance, and its 1.91 eV bandgap is close to the optimal bandgap of indoor artificial light sources, making it be the best candidate for the indoor photovoltaics (IPVs) to power a wide range of internet of things related electronic devices. Herein, we report on the preparation of CsPbI2 Br with α-phase and the improvement of its phase stability by adding lead acetate in the CsPbI2 Br precursor. A series of dopant-free conjugated polymers (P3HT, PBDB-T, and PM6) with different highest occupied molecular orbital energy levels are introduced as hole transport layers for building IPV devices. The PM6 based devices having better energy alignment with perovskite demonstrate best indoor photovoltaic performance, giving a remarkable open-circuit voltage of 1.15 V and high fill factor of 81.86% under 1000 lux (330 µW cm-2 ) light-emitting diode illumination, and finally realizing a decent power conversion efficiency of 33.68%. Our findings suggest that collaboratively optimize the CsPbI2 Br layer and hole transport layer is an effective approach to realize high performance IPVs.

9.
Polymers (Basel) ; 14(14)2022 Jul 07.
Article in English | MEDLINE | ID: mdl-35890558

ABSTRACT

A large number of drainage pipes and canals in China have been in disrepair for a long time and there have been problems such as leakage and corrosion. In response to these problems, this paper studies a non-excavation technology for repairing the arched canal structure-the in-situ spraying method. To study the influence of the original canal structure on the mechanical characteristics of the lining structure by in-situ spraying and the restraint effect on the lining structure, a field model test with a similar ratio of 1:2 was conducted in the field test pit. By conducting four stages of three-point concentrated load loading tests, the mechanical characteristics of the lining structure were investigated to reveal the influence of the canal structure on the force of the lining structure. The test results show that: the maximum crack width of the newly added lining structure is 0.27 mm and the normal service ultimate bearing capacity of the arched structure repaired by H-70 reaches 150 kN; comparing the loading test and the numerical simulation results, the difference between the two vault displacement results is 4.65% and the results are relatively consistent. The displacement of the bottom of the lining structure is small and the participation of the bottom plate is small, while the displacement of the upper arch structure of the lining is significantly larger than the lateral displacement, indicating that the canal structure can effectively limit the lateral displacement of the newly added lining and that the canal structure is greatly reduced. The bending moment of the lining structure is improved and the restraint effect on the arch foot is more obvious. This paper proposes the use of H-70 to repair arched canal structures by the in-situ spraying method and seeks to prove the feasibility of this method and fill the gap of research in this area. This paper provides the structural design basis and experimental knowledge for the construction of the repair method, which has important practical significance for the pipeline repair project in the future.

10.
Int J Med Inform ; 160: 104694, 2022 04.
Article in English | MEDLINE | ID: mdl-35144100

ABSTRACT

BACKGROUND: Coronavirus disease 2019 (COVID-19) has caused a global pandemic that has driven the widespread use of applications (apps) for outbreak management in China, but the characteristics and quality of these apps are currently unknown. OBJECTIVE: The first objective of this study was to investigate the functional characteristics of individual epidemic prevention and control apps in China, and the second objective was to evaluate the quality of these apps. METHODS: We searched the QimaiTM mobile application data analysis platform and the AladdinTM WeChat applet data analysis platform with keywords and quantified the search results based on the search index, relevance, and the Aladdin index to identify apps with high public popularity. The quality of the apps was rated by 2 independent raters using the Mobile App Rating Scale (MARS). The intraclass correlation coefficient (ICC) between raters was used as a measure of interrater reliability. RESULTS: All 20 of the included apps had acceptable quality. Functionality had the highest score, followed by information quality, aesthetics, and engagement. There were no significant differences between the independent apps and WeChat applets in app quality (t = 1.907, p = 0.073) and subjective quality (t = 0.899, p = 0.381). These apps were related to COVID-19 individual prevention and control, and the functional features that contributed to the quality of the apps were grouped into six categories, i.e., health self-checking and reporting, news about COVID-19, scientific publicity and education, telemedicine services, personal travel inquiries, and digital contact tracing. CONCLUSIONS: Individual COVID-19 prevention and control apps in China were developed by adding epidemic prevention and control functions to existing social apps rather than independently developing apps. The overall quality of such apps was acceptable, but scores in the engagement section were generally low, especially for WeChat applets.


Subject(s)
COVID-19 , Mobile Applications , COVID-19/epidemiology , COVID-19/prevention & control , Humans , Pandemics/prevention & control , Reproducibility of Results , SARS-CoV-2
11.
J Med Internet Res ; 24(1): e26308, 2022 01 31.
Article in English | MEDLINE | ID: mdl-35099401

ABSTRACT

BACKGROUND: The internet has become one of the most important channels for residents to seek health information, particularly in remote rural areas in China. OBJECTIVE: In this study, we aimed to explore the gap between self-rated health information literacy and internet health information seeking ability for patients with chronic diseases in rural communities and to preliminarily evaluate their barriers when seeking health information via the internet. METHODS: Residents from rural communities near Bengbu City and with chronic diseases were included in this study. A self-rated questionnaire was used to evaluate their health information literacy, 3 behavioral competency tasks were designed to preliminarily evaluate their ability to seek health information on the internet and semistructured interviews were used to investigate their barriers to obtaining health information via the internet. A small audiorecorder was used to record the interview content, and screen-recording software was used to record the participants' behavior during the web-based operational tasks. RESULTS: A total of 70 respondents completed the self-rated health information literacy questionnaire and the behavioral competence test, and 56 respondents participated in the semistructured interviews. Self-rated health information literacy (score out of 70: mean 46.21, SD 4.90) of the 70 respondents were moderate. Although 91% (64/70) of the respondents could find health websites, and 93% (65/70) of the respondents could find information on treatment that they thought was the best, 35% (23/65) of respondents did not know how to save the results they had found. The operational tasks indicated that most articles selected by the respondents came from websites with encyclopedic knowledge or answers from people based on their own experiences rather than authoritative health information websites. After combining the results of the semistructured interviews with the DISCERN scale test results, we found that most interviewees had difficulty obtaining high-quality health information via the internet. CONCLUSIONS: Although the health information literacy level of patients with rural chronic disease was moderate, they lack the ability to access high-quality health information via the internet. The vast majority of respondents recognized the importance of accessing health information but were not very proactive in accessing such information.


Subject(s)
Health Literacy , Telemedicine , Chronic Disease , Cross-Sectional Studies , Health Literacy/methods , Humans , Information Seeking Behavior , Internet , Rural Population , Surveys and Questionnaires , Telemedicine/methods
12.
J Nurs Manag ; 30(2): 375-383, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34845777

ABSTRACT

AIM: To explore the experiences of nurses' work stress related to COVID-19 regular epidemic prevention and control in China. BACKGROUND: The global COVID-19 epidemic is still severe, and China's ongoing regular epidemic prevention and control still cannot be relaxed, which places demands on nurses. METHODS: Thirty nurses and eight nurse managers were interviewed using semistructured in-depth interviews, and the data were analysed by the Colaizzi seven-step analysis method. RESULTS: Four themes were extracted as follows: environmental factors, organizational factors, personal factors and positive factors in coping with stress. CONCLUSIONS: Nursing managers should pay attention to construction of the first-line departments of regular epidemic prevention and control. The shortage of nurses' human resources and the increase of nurse-patient conflicts are problems that need to be solved urgently. In addition, this research also emphasizes the importance of promoting nurses' stress-related growth and thinking about the possibility of reform. IMPLICATIONS FOR NURSING MANAGEMENT: The construction of the hospital environment and increasing the resilience of nursing teams require attention. We should attach importance to the training of nurses' communication skills and provide sufficient organizational support and economic guarantees for nurses. Finally, perhaps we should also consider whether it is necessary to reform the relevant hospital systems and how to reform them.


Subject(s)
COVID-19 , Nurse Administrators , Nurses , Nursing Staff, Hospital , COVID-19/epidemiology , COVID-19/prevention & control , China/epidemiology , Humans , Qualitative Research , SARS-CoV-2
13.
JMIR Cancer ; 7(4): e25783, 2021 Nov 18.
Article in English | MEDLINE | ID: mdl-34792471

ABSTRACT

BACKGROUND: In China, the internet has become one of the most important ways to obtain information about breast cancer. However, quantitative evaluations of the quality of Chinese health websites and the breast cancer treatment information they publish are lacking. OBJECTIVE: This study aimed to evaluate the quality of Chinese breast cancer websites and the value, suitability, and accuracy of the breast cancer treatment information they publish. METHODS: Chinese breast cancer health websites were searched and manually screened according to their Alexa and Baidu search engine rankings. For each website included in the survey, which was conducted on April 8, 2019, the three most recently published papers on the website that met the inclusion criteria were included for evaluation. Three raters assessed all materials using the LIDA, DISCERN, and Suitability Assessment of Materials (SAM) tools and the Michigan Checklist. Data analysis was completed with the Statistical Package for Social Sciences (SPSS) version 20.0 and Microsoft Excel 2010. RESULTS: This survey included 20 Chinese breast cancer websites and 60 papers on breast cancer treatment. The LIDA tool was used to evaluate the quality of the 20 websites. The LIDA's scores of the websites (mean=54.85, SD 3.498; total possible score=81) were low. In terms of the layout, color scheme, search facility, browsing facility, integration of nontextual media, submission of comments, declaration of objectives, content production method, and robust method, more than half of the websites scored 0 (never) or 1 (sometimes). For the online breast cancer treatment papers, the scores were generally low. Regarding suitability, 32 (53.33%) papers were evaluated as presenting unsuitable material. Regarding accuracy, the problems were that the papers were largely not original (44/60, 73%) and lacked references (46/60, 77%). CONCLUSIONS: The quality of Chinese breast cancer websites is poor. The color schemes, text settings, user comment submission functions, and language designs should be improved. The quality of Chinese online breast cancer treatment information is poor; the information has little value to users, and pictorial information is scarcely used. The online breast cancer treatment information is accurate but lacks originality and references. Website developers, governments, and medical professionals should play a full role in the design of health websites, the regulation of online health information, and the use of online health information.

14.
Small ; 17(12): e2007363, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33656799

ABSTRACT

High performance and super stable all-inorganic full-color quantum dot light-emitting diodes (QLEDs) are constructed by adopting solution-processed Mg-doped NiOx (Mg-NiOx ) nanoparticles as hole transport layer (HTL) and Al-doped ZnO (AZO) as electron transport layer (ETL). Mg-NiOx nanoparticles possess the advantages of low-temperature solution processability, intrinsic stability, and controllable electronic properties. UV-ozone (UVO) treatment is applied to the Mg-NiOx film to modulate its surface composition. By carefully controlling the UVO treating time, favorable energy levels can be achieved to minimize the energy barrier for hole injection. At the cathode side, Al-doping can reduce the conductivity of ZnO ETL and decrease the interface charge transfer, effectively, thus leading to more balanced charge injection and consequent high luminance and efficiency. The maximum luminance and EQE can reach as high as 38 444 cd m-2 and 5.09% for R-QLEDs, 177 825 cd m-2 and 10.1% for G-QLEDs, and 3103 cd m-2 and 2.19% for B-QLEDs. The luminance values are the highest ever reported for all-inorganic QLEDs. Furthermore, the all-inorganic devices show much better resistance to water and oxygen existing in air. The results show that the ion-doped NiOx and AZO nanoparticles would facilitate the design and development of highly efficient and super stable QLEDs.

15.
J Ment Health ; 30(2): 263-270, 2021 Apr.
Article in English | MEDLINE | ID: mdl-32816536

ABSTRACT

BACKGROUND: Mental health literacy (MHL) is vital for raising mental health awareness, reducing stigma, and improving health-related decision making, which may have lifelong consequences for patients with mental disorders. AIMS: To examine MHL about depression among rural left-behind children (LBC) in China and explore differences between LBC and non-left-behind children (NLBC). METHODS: A total of 3456 rural school children (mean age = 13.02 years) in fourth to ninth grades who were living in Sichuan, Anhui, and Henan provinces were surveyed in April and July 2018 using stratified random cluster sampling. RESULTS: More NLBC correctly recognized depression compared with LBC (p < 0.05). The most common sources of mental health information were the TV and the Internet. LBC felt more uneasy if they asked for help (p < 0.01). Statistical differences in help-seeking barriers were observed between LBC and NLBC (p < 0.05). CONCLUSIONS: Respondents showed low levels of depression-related MHL compared with peer groups in other countries, LBC showed lower MHL than NLBC in terms of the correct recognition rate of depression, attitude toward seeking help, etc. More school-based interventions should be implemented in rural schools, and parent involvement and digital-based educational strategies should be considered.


Subject(s)
Depression/epidemiology , Health Knowledge, Attitudes, Practice , Health Literacy , Mental Health , Adolescent , Child , China/epidemiology , Cross-Sectional Studies , Help-Seeking Behavior , Humans , Rural Population , Surveys and Questionnaires
16.
Nanoscale ; 12(25): 13186-13224, 2020 Jul 02.
Article in English | MEDLINE | ID: mdl-32614007

ABSTRACT

Colloidal quantum dots (QDs) have attracted extensive attention due to their excellent optoelectronic properties, such as high quantum efficiency, narrow emission peaks, high color saturation, high stability and solution processability. Compared with the traditional display technology, QD based light-emitting diodes (QLEDs) show broad application prospects in the field of flat-panel displays and solid-state lighting. However, for full-color displays, the efficiency and lifetime of blue QLEDs are inferior to those of their green and red counterparts. Therefore, it is urgent for us to deeply understand the device physics and improve the performance of blue QLEDs through material and device engineering. An in-depth understanding of the optoelectronic properties (such as the structure of electronic states, electron-phonon interactions, Auger processes, etc.) and material engineering (such as size distribution control, composition control, and surface engineering) of blue emission QDs is greatly helpful for their applications in other fields. Herein, we review the key progress in the area of blue QLEDs, including the compositions and nanostructures of blue quantum dots, advances in the device architectures and the improvement of the device lifetime of blue QLEDs. The key factors that influence the blue device performance, including the nanostructure design and surface modification of QDs, interface engineering and architecture design of devices are discussed, aiming to propose possible solutions for these challenges, which will help to promote the commercialization process of QLEDs.

17.
Small ; 16(32): e2002940, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32583597

ABSTRACT

For quasi-2D perovskite light-emitting diodes, the introduction of insulating bulky cation reduces the charge transport property, leading to lowered brightness and increased turn-on voltage. Herein, a dual-ligand strategy is adopted to prepare perovskite films by using an appropriate ratio of i-butylammonium (iBA) and phenylethylammonium (PEA) as capping ligands. The introduction of iBA enhances the binding energy of the ligands on the surface of the quasi-2D perovskite, and effectively controls the proportion of 2D perovskite to allow more efficient energy transfer, resulting in the great enhancement of the electric and luminescent properties of the perovskite. The photoluminescence (PL) mapping of the perovskite films exhibits that enhanced photoluminescence performance with better uniformity and stronger intensity can be achieved with this dual-ligand strategy. By adjusting the proportion of the two ligands, sky-blue perovskite light-emitting diodes (PeLEDs) with electroluminescence (EL) peak located 485 nm are achieved with a maximum luminance up to 1130 cd m-2 and a maximum external quantum efficiency (EQE) up to 7.84%. In addition, the color stability and device stability are significantly enhanced by using a dual-ligand strategy. This simple and feasible method paves the way for improving the performance of quasi-2D PeLEDs.

18.
JMIR Mhealth Uhealth ; 8(5): e14826, 2020 05 08.
Article in English | MEDLINE | ID: mdl-32383684

ABSTRACT

BACKGROUND: As representatives of health information communication platforms accessed through mobile phones and mobile terminals, health-related WeChat public accounts (HWPAs) have a large consumer base in the Chinese-speaking world. However, there is still a lack of general understanding of the status quo of HWPAs and the quality of the articles they release. OBJECTIVE: The aims of this study were to assess the conformity of HWPAs to the Health on the Net Foundation Code of Conduct (HONcode) and to evaluate the suitability of articles disseminated by HWPAs. METHODS: The survey was conducted from April 23 to May 5, 2019. Based on the monthly (March 1-31, 2019) WeChat Index provided by Qingbo Big Data, the top 100 HWPAs were examined to evaluate their HONcode compliance. The first four articles published by each HWPA on the survey dates were selected as samples to evaluate their suitability. All materials were assessed by three raters. The materials were assessed using the HONcode checklist and the Suitability Assessment of Materials (SAM) score sheet. Data analysis was performed with SPSS version 17.0 (SPSS Inc, Chicago, IL, USA) and Excel version 2013 (Microsoft Inc, Washington DC, USA). RESULTS: A total of 93 HWPAs and 210 of their released articles were included in this study. For six of the eight principles, the 93 HWPAs nearly consistently did not meet the requirements of the HONcode. The HWPAs certified by Tencent Corporation (66/93, 71%) were generally slightly superior to those without such certification (27/93, 29%) in terms of compliance with HONcode principles. The mean SAM score for the 210 articles was 67.72 (SD 10.930), which indicated "adequate" suitability. There was no significant difference between the SAM scores of the articles published by certified and uncertified HWPAs (P=.07), except in the literacy requirements dimension (tdf=97=-2.418, P=.02). CONCLUSIONS: The HWPAs had low HONcode conformity. Although the suitability of health information released by HWPAs was at a moderate level, there were still problems identified, such as difficulty in tracing information sources, excessive implicit advertisements, and irregular usage of charts. In addition, the low approval requirements of HWPAs were not conducive to improvement of their service quality.


Subject(s)
Communication , Chicago , Cross-Sectional Studies , Humans , Surveys and Questionnaires
19.
J Phys Chem Lett ; 11(3): 1120-1127, 2020 Feb 06.
Article in English | MEDLINE | ID: mdl-31967834

ABSTRACT

Lead halide perovskites have attracted tremendous attention because of their impressive optoelectronic properties. However, the toxicity of lead remains a bottleneck for further commercial development. Two-dimensional Ruddlesden-Popper tin-based perovskites are lead-free and more stable compared to their three-dimensional counterparts, which have great potential in the optoelectronic device field. Herein, we demonstrate high-quality two-dimensional phenylethylammonium tin-iodide perovskite (PEA2SnI4) thin films by using toluene as the antisolvent. Furthermore, the PeLED performance is greatly improved by replacing the PEAI spacer cation with 2-thiopheneethyllamine iodide (TEAI). As a result, a TEA-based PeLED device is achieved with a low turn-on voltage of 2.3 V, a maximum luminance of 322 cd m-2, and maximum external quantum efficiency of 0.62%, which are the highest efficiency and brightness for pure red (emission peak = 638 nm) tin-based PeLEDs to date.

20.
J Phys Chem Lett ; 10(5): 960-965, 2019 Mar 07.
Article in English | MEDLINE | ID: mdl-30739455

ABSTRACT

For blue quantum dot (QD) light-emitting diodes (QLEDs), the imbalance of charges transport and injection severely affects their efficiency and lifetime. A better charge balance can be realized by improving hole injection while suppressing redundant electrons. Introducing dopants into charge transport layers (CTLs) is an effective and simple strategy to modulate the charge injection barrier and mobility. In this work, optoelectronic simulation is performed to investigate the change in physical process within the devices upon CTL doping. The results confirm that the charge distribution in the QD layer is more balanced and the recombination rate is greatly improved. Under the guidance of theoretical simulation, high-performance blue QLEDs were achieved by fine-tuning the charge balance through CTL doping. The luminance and external quantum efficiency have been dramatically increased from 18 679 to 34 874 cd/m2 and from 4.7 to 10.7%, respectively. The operation lifetime is also improved ∼3.5 times due to the more balanced charge injection.

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