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1.
Small ; : e2402402, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949051

RESUMO

Doping transition metal oxide spinels with metal ions represents a significant strategy for optimizing the electronic structure of electrocatalysts. Herein, a bimetallic Fe and Ru doping strategy to fine-tune the crystal structure of CoV2O4 spinel for highly enhanced oxygen evolution reaction (OER) is presented performance. The incorporation of Fe and Ru is observed at octahedral sites within the CoV2O4 structure, effectively modulating the electronic configuration of Co. Density functional theory calculations have confirmed that Fe acts as a novel reactive site, replacing V. Additionally, the synergistic effect of Fe, Co, and Ru effectively optimizes the Gibbs free energy of the intermediate species, reduces the reaction energy barrier, and accelerates the kinetics toward OER. As expected, the best-performing CoVFe0.5Ru0.5O4 displays a low overpotential of 240 mV (@10 mA cm-2) and a remarkably low Tafel slope of 38.9 mV dec-1, surpassing that of commercial RuO2. Moreover, it demonstrates outstanding long-term durability lasting for 72 h. This study provides valuable insights for the design of highly active polymetallic spinel electrocatalysts for energy conversion applications.

2.
J Phys Chem Lett ; 15(30): 7584-7590, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39025480

RESUMO

Exciton-phonon coupling (ExPC) is crucial for energy relaxation in semiconductors, yet the first-principles calculation of such coupling remains challenging, especially for two-dimensional (2D) systems. Here, an accurate method for calculating ExPC is developed and applied in exciton relaxation problems in monolayer WSe2. Considering the interplay between the exciton wave functions and electron-phonon coupling (EPC) matrix elements, we find that ExPC shows selection rules distinct from the ones of EPC. By employing the Wannier exciton model, we generalize these selection rules, which state that the angular quantum numbers of the exciton must match the winding numbers of the EPC matrix elements for the ExPC to be allowed. To verify our theory and method, we calculate intervalley exciton relaxation pathways, which agree well with a recent experiment.

3.
Front Nutr ; 11: 1440025, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39077159

RESUMO

Objective: There is limited research on the relationship between the frequency of plant-based food intake and the risk of cardiovascular disease (CVD) among elderly Chinese. This study aims to evaluate the association between plant-based dietary index (PDI) and CVD risks, providing evidence for elderly Chinese to reduce CVD risks by increasing the frequency of plant-based food consumption. Methods: This study analyzed data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) 2011-2018, employing a multivariate modified Poisson regression model, trend tests, and restricted cubic spline (RCS) analysis to assess the linear and non-linear relationship between the PDI and CVD risks. Subgroup analyses and interaction tests were conducted to evaluate the robustness and population-specificity of the results. Results: This study included a total of 1,414 elderly Chinese, and at the end of follow-up, 487 participants had developed CVD. The multivariate modified Poisson regression model revealed a negative association between PDI and CVD risks [RR = 0.983, 95%CI = (0.970, 0.997)]. Similarly, the multivariate trend test (p = 0.031) and RCS analysis (P for nonlinear = 0.600) indicated a linear relationship between PDI and CVD risks. Subgroup analyses showed that the relationship between PDI and CVD risk was not influenced by gender, BMI, smoking, alcohol use, or exercise. Conclusion: The PDI was negatively correlated with CVD risks, indicating that increasing the frequency of plant-based food intake in the diet may reduce CVD risks among elderly Chinese.

4.
J Colloid Interface Sci ; 673: 19-25, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38870664

RESUMO

Developing highly active and durable non-precious metal-based electrocatalysts for the oxygen evolution reaction (OER) is crucial in achieving efficient energy conversion. Herein, we reported a CoNiAl0.5O/NF nanofilament that exhibits higher OER activity than previously reported IrO2-based catalysts in alkaline solution. The as-synthesized CoNiAl0.5O/NF catalyst demonstrates a low overpotential of 230 mV at a current density of 100 mA cm-2, indicating its high catalytic efficiency. Furthermore, the catalyst exhibits a Tafel slope of 26 mV dec-1, suggesting favorable reaction kinetics. The CoNiAl0.5O/NF catalyst exhibits impressive stability, ensuring its potential for practical applications. Detailed characterizations reveal that the enhanced activity of CoNiAl0.5O/NF can be attributed to the electronic modulation achieved through Al3+ incorporation, which promotes the emergence of higher-valence Ni metal, facilitating nanofilament formation and improving mass transport and charge transfer processes. The synergistic effect between nanofilaments and porous nickel foam (NF) substrate significantly enhances the electrical conductivity of this catalyst material. This study highlights the significance of electronic structures for improving the activity of cost-effective and non-precious metal-based electrocatalysts for the OER.

5.
Phys Rev Lett ; 132(8): 086101, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38457702

RESUMO

The exploration of solid-solid phase transition suffers from the uncertainty of how atoms in two crystal structures match. We devised a theoretical framework to describe and classify crystal-structure matches (CSM). Such description fully exploits the translational and rotational symmetries and is independent of the choice of supercells. This is enabled by the use of the Hermite normal form, an analog of reduced echelon form for integer matrices. With its help, exhausting all CSMs is made possible, which goes beyond the conventional optimization schemes. In an example study of the martensitic transformation of steel, our enumeration algorithm finds many candidate CSMs with lower strains than known mechanisms. Two long-sought CSMs accounting for the most commonly observed Kurdjumov-Sachs orientation relationship and the Nishiyama-Wassermann orientation relationship are unveiled. Given the comprehensiveness and efficiency, our enumeration scheme provide a promising strategy for solid-solid phase transition mechanism research.

6.
ACS Appl Mater Interfaces ; 16(14): 17432-17441, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38544402

RESUMO

Z-scheme heterostructure-based photocatalysts consist of a reduction photocatalyst and an oxidation photocatalyst, enabling them to possess a high capacity for both reduction and oxidation. However, the coupling reaction between photocatalytic H2 generation through water reduction and sterilization using Z-scheme systems has been rarely reported. Herein, 1D W18O49 nanowires embedded over 2D g-C3N4 nanosheets are well-constructed as an integrated Z-scheme heterojunction. Experimental results and density functional theory calculations not only demonstrate the achievement of efficient interfacial charge separation and transport, leading to prolonged lifetime of photogenerated charge carriers, but also directly confirm the mechanism of Z-scheme charge transfer. As expected, the optimized W18O49/g-C3N4 nanostructure exhibits superior photocatalytic sterilization activity against Staphylococcus aureus as well as excellent H2 generation performance under visible-light irradiation (λ ≥ 420 nm). Due to its nontoxic nature, W18O49/g-C3N4 holds great potential in eradicating bacterial infections in living organisms.


Assuntos
Bactérias , Luz , Isótopos de Oxigênio , Catálise
7.
Phys Rev E ; 109(2-1): 024118, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38491632

RESUMO

The supercritical region is often described as uniform with no definite transitions. The distinct behaviors of the matter therein, e.g., as liquidlike and gaslike, however, suggest "supercritical boundaries." Here we provide a mathematical description of these phenomena by revisiting the Yang-Lee theory and introducing a complex phase diagram, specifically a four-dimensional (4D) one with complex T and p. While the traditional 2D phase diagram with real temperature T and pressure p values (the physical plane) lacks Lee-Yang (LY) zeros beyond the critical point, preventing the occurrence of criticality, the off-plane zeros in this 4D scenario still induce critical anomalies in various physical properties. This relationship is evidenced by the correlation between the Widom line and LY edges in van der Waals, 2D Ising model, and water. The diverged supercritical boundaries manifest the high-dimensional feature of the phase diagram: e.g., when LY zeros of complex T or p are projected onto the physical plane, boundaries defined by isobaric heat capacity C_{p} or isothermal compression coefficient K_{T} emanates. These results demonstrate the incipient phase transition nature of the supercritical matter.

8.
Cardiovasc Diabetol ; 23(1): 86, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38419039

RESUMO

BACKGROUND: Studies on the relationship between insulin resistance (IR) surrogates and long-term all-cause mortality in patients with coronary heart disease (CHD) and hypertension are lacking. This study aimed to explore the relationship between different IR surrogates and all-cause mortality and identify valuable predictors of survival status in this population. METHODS: The data came from the National Health and Nutrition Examination Survey (NHANES 2001-2018) and National Death Index (NDI). Multivariate Cox regression and restricted cubic splines (RCS) were performed to evaluate the relationship between homeostatic model assessment of IR (HOMA-IR), triglyceride glucose index (TyG index), triglyceride glucose-body mass index (TyG-BMI index) and all-cause mortality. The recursive algorithm was conducted to calculate inflection points when segmenting effects were found. Then, segmented Kaplan-Meier analysis, LogRank tests, and multivariable Cox regression were carried out. Receiver operating characteristic (ROC) and calibration curves were drawn to evaluate the differentiation and accuracy of IR surrogates in predicting the all-cause mortality. Stratified analysis and interaction tests were conducted according to age, gender, diabetes, cancer, hypoglycemic and lipid-lowering drug use. RESULTS: 1126 participants were included in the study. During the median follow-up of 76 months, 455 participants died. RCS showed that HOMA-IR had a segmented effect on all-cause mortality. 3.59 was a statistically significant inflection point. When the HOMA-IR was less than 3.59, it was negatively associated with all-cause mortality [HR = 0.87,95%CI (0.78, 0.97)]. Conversely, when the HOMA-IR was greater than 3.59, it was positively associated with all-cause mortality [HR = 1.03,95%CI (1.00, 1.05)]. ROC and calibration curves indicated that HOMA-IR was a reliable predictor of survival status (area under curve = 0,812). No interactions between HOMA-IR and stratified variables were found. CONCLUSION: The relationship between HOMA-IR and all-cause mortality was U-shaped in patients with CHD and hypertension. HOMA-IR was a reliable predictor of all-cause mortality in this population.


Assuntos
Doença das Coronárias , Hipertensão , Resistência à Insulina , Humanos , Estudos Longitudinais , Inquéritos Nutricionais , Glicemia , Estudos de Coortes , Hipertensão/diagnóstico , Doença das Coronárias/diagnóstico , Triglicerídeos , Glucose , Biomarcadores
9.
Front Cardiovasc Med ; 11: 1308592, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38327493

RESUMO

Background: The relationship between sleep characteristics and cardiovascular disease (CVD) risk has yet to reach a consistent conclusion, and more research needs to be carried out. This study aimed to explore the relationship between snoring, daytime sleepiness, bedtime, sleep duration, and high-risk sleep patterns with CVD risk. Methods: Data from the National Health and Nutrition Examination Survey (NHANES) 2015-2018 were collected and analyzed. Multivariable logistic regression was used to evaluate the relationship between snoring, daytime sleepiness, bedtime, sleep duration, high-risk sleep patterns, and CVD risk. Stratified analysis and interaction tests were carried out according to hypertension, diabetes and age. Results: The final analysis contained 6,830 participants, including 1,001 with CVD. Multivariable logistic regression suggested that the relationship between snoring [OR = 7.37,95%CI = (6.06,8.96)], daytime sleepiness [OR = 11.21,95%CI = (9.60,13.08)], sleep duration shorter than 7 h [OR = 9.50,95%CI = (7.65,11.79)] or longer than 8 h [OR = 6.61,95%CI = (5.33,8.19)], bedtime after 0:00 [OR = 13.20,95%CI = (9.78,17.80)] compared to 22:00-22:59, high-risk sleep patterns [OR = 47.73,95%CI = (36.73,62.04)] and CVD risk were statistically significant. Hypertension and diabetes interacted with high-risk sleep patterns, but age did not. Conclusions: Snoring, daytime sleepiness, excessive or short sleep duration, inappropriate bedtime, and high-risk sleep patterns composed of these factors are associated with the CVD risk. High-risk sleep patterns have a more significant impact on patients with hypertension and diabetes.

10.
Exp Appl Acarol ; 92(2): 297-305, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38351236

RESUMO

As one of the most important disease vectors worldwide, ticks can transmit a number of pathogenic organisms to humans and domestic animals and cause a variety of important natural focal diseases and zoonoses. Domestic livestock play a vital role in the dispersal of ticks from the field environment to the human settlement, contributing to the prevalence of tick-borne diseases. Identification of the tick control region could contribute a vital role in strategic planning and cost-effective tick control measures. However, little is known about the spatial distribution characteristics of ticks around livestock sheds, which will lead to abusage and overuse of insecticides. Therefore, this study aimed to explore spatial distribution characteristics and correlation factors of ticks around goat sheds. A total of 3898 ticks were collected from eight goat sheds from April to June in Jinan city. All the sampled ticks belonged to the same species, namely Haemaphysalis longicornis, and 88.8% of them were nymphs. A significant positive correlation was noted between free-living ticks and parasitic ticks (r = 0.411, P < 0.001). However, there was a significant negative correlation between number of free-living ticks and distance from the goat sheds (r = -0.622, P < 0.001). Within 20 m from the goat sheds, 2211 ticks were collected respectively, representing 56.7% of the total free-living ticks. At a distance of 30 m, 57.6% decline in the tick density was found with a significant difference (q = 5.534, P < 0.001). In conclusion, focusing control efforts near the goat sheds should be recommend for tick prevention and control.


Assuntos
Ixodidae , Carrapatos , Animais , Humanos , Cabras , Haemaphysalis longicornis , Animais Domésticos , China/epidemiologia , Gado
11.
Journal of Clinical Hepatology ; (12): 1446-1449, 2024.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1038662

RESUMO

About 1% of the patients with acute hepatitis B can progress to acute liver failure, and 75% of the patients with hepatitis B virus (HBV)-related acute liver failure need to undergo liver transplantation or face death. This article reports a patient with HBV infection-related acute liver failure who achieved clinical cure and HBsAg seroconversion after antiviral therapy and symptomatic/supportive treatment, and dynamic monitoring was performed for immunological markers in peripheral blood.

12.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1021934

RESUMO

BACKGROUND:Osteonecrosis of the femoral head is one of the refractory diseases in orthopedic diseases.The natural collapse course of osteonecrosis of the femoral head under different stages and types affects the progression and prognosis of the disease. OBJECTIVE:To explore the progression of natural collapse within 5 years in patients under the different classifications of China-Japan Friendship Hospital(CJFH)with stage Ⅱ osteonecrosis of the International Association for Research Circulation Osseous(ARCO),and to analyze the collapse rate and collapse risk of the femoral head under the different classifications of CJFH. METHODS:A retrospective study was performed to select patients diagnosed with ARCO Ⅱ stage osteonecrosis of the femoral head without collapse in the Honghui Hospital Affiliated to Xi'an Jiaotong University from October 2016 to October 2017.According to whether it collapsed,the number of hips was divided into the collapse group(n=82)and the non-collapsed group(n=70).The collapse risk of patients with osteonecrosis of the femoral head under different CJFH classifications,as well as the collapse time,number of collapses,and collapse rate within 5 years were counted,and then the Kaplan-Meier survival curve of the femoral head under different classification of CJFH was plotted. RESULTS AND CONCLUSION:(1)A total of 97 patients with 152 hips were enrolled,and 82 hips collapsed during the follow-up period,with a total collapse rate of 53.9%,of which the collapse rates of M type,C type,L1 type,L2 type,and L3 type were 0.0%,36.7%,51.4%,72.2%,and 77.8%,respectively,and the comparison between the groups was statistically significant(P<0.05).(2)In terms of collapse risk,the collapse risk of L1 type was 1.704 times that of C-type(P>0.05),while the collapse risks of L2 type and L3 type were 3.866 times and 6.423 times that of C type(P<0.05),respectively.(3)In terms of the Kaplan-Meier survival curve,the median survival time of the femoral head of ARCO Ⅱ stage patients was 3 years,with a 95%confidence interval of 2.885-3.471 years,and the survival rates of the femoral head at the first,third and fifth years were 65.1%(99/152),50.7%(77/152),and 46.1%(70/152),respectively.(4)These findings conclude that different CJFH classifications affect the collapse rate of ARCO Ⅱ stage osteonecrosis of the femoral head patients,among which L3 type patients have the highest collapse rate,followed by L2 type and L1 type patients;C type patients have a lower collapse rate,and M type patients do not collapse,which indicates that the preservation of the lateral column of the femoral head is of great significance for the natural collapse course of osteonecrosis of the femoral head.

13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1026285

RESUMO

Objective To observe the value of diffusion weighted imaging intravoxel incoherent motion(IVIM)for quantitative evaluating chronic allograft dysfunction(CAD).Methods Totally 104 CAD patients were prospectively enrolled and were assigned into CAD 1,2 and 3 groups(n=11,61,32)based on impairment severity of estimated renal function,and 36 healthy volunteers were enrolled as control group.The true diffusion coefficient(D value),microcirculation perfusion diffusion coefficient(D*value)and perfusion score(f value)of renal cortex and medulla IVIM parameters were compared among groups and within groups to assess the value of IVIM parameters for diagnosing CAD.Results The D value of transplanted renal cortex in all CAD groups were lower than that in control group(all P<0.05),which decreased among CAD 1,2 and 3 groups(all P<0.05).The D value of transplanted kidney medulla in CAD 2 and 3 groups were lower than that in control group(both P<0.05).The D*values of transplanted renal cortex in all CAD groups were lower than that in control group,while of renal medulla in CAD 2 and 3 groups were lower than that in control group(both P<0.05).The f values of cortex and medulla in CAD 2 and 3 groups were lower than those in control group(all P<0.05),while of cortex in CAD 3 group was lower than that in CAD 1 and 2 groups(both P<0.05).The area under the curve(AUC)of cortical IVIM combined model for diagnosing CAD was 0.96,better than the D*value and f value(AUC=0.74,0.83,P<0.05)but not significantly different with that of the D value(AUC=0.94,P=0.32).AUC of medullary IVIM combined model for diagnosing CAD was 0.91,better than that of D,D*and f value(AUC=0.80,0.67 and 0.80,all P<0.05).Conclusion IVIM parameters could be used to quantitatively evaluate CAD.

14.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1029507

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by Dabie bandavirus (DBV), characterized by fever, leukopenia, thrombocytopenia and multiple organ damage. Immune dysfunction induced by DBV is closely associated with the pathogenesis of SFTS. Monocytes/macrophages that are essential in innate immunity are the target cells of DBV, and their interaction with DBV plays an important role in the pathogenesis of SFTS. The review summarizes the progress in the features and mechanisms of monocyte/macrophage-mediated immune responses to DBV infection.

16.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1021328

RESUMO

BACKGROUND:For non-traumatic osteonecrosis of the femoral head,if the femoral head collapses,it will have a great impact on the normal life of the patients.Thus,it is necessary to use an appropriate way to evaluate the risk of femoral head collapse and then to take targeted measures to delay the process of femoral head collapse. OBJECTIVE:To analyze the natural course of early osteonecrosis of the femoral head(without collapse)under different locations of necrotic lesions. METHODS:121 patients(191 hips)with early non-traumatic osteonecrosis of the femoral head who were treated in the Outpatient Department of Honghui Hospital Affiliated to Xi'an Jiaotong University from October 2016 to October 2017 were enrolled in this study.The clinical data of all patients were followed up for 5 years to observe the collapse of osteonecrosis of the femoral head and the risk coefficient of femoral head collapse among different JIC types.The collapse rate of osteonecrosis of the femoral head was calculated during the follow-up. RESULTS AND CONCLUSION:(1)A total of 191 hips were included in this study.The femoral head collapsed in 86 hips during follow-up,with a total collapse rate of 45.0%.Among the influencing factors,age,ARCO stage and JIC classification were the main influencing factors of femoral head collapse(P<0.05),but body mass index,sex,incidence side and pathogenic factors were not the main influencing factors(P>0.05).(2)Among 191 hips,in JIC classification,the total collapse rates of type A,type B,type C1 and type C2 were 11.1%(2/18),30.2%(16/53),52.4%(43/82),and 65.8%(25/38),respectively.There were significant differences in the total collapse rate of the femoral head among all types(P<0.05).The collapse risk results showed that the collapse risk of type B,type C1 and type C2 was 2.41,5.22 and 7.89 times higher than that of type A,respectively.(3)Both JIC classification and ARCO stage were correlated with femoral head collapse(P<0.01).There was no significant difference in the collapse rate of the femoral head among all JIC types in ARCO I stage hips(P>0.05).In the hips with ARCO II stage,the collapse rates of the femoral head of JIC types A,B,C1 and C2 were 1.2%,19.5%,50.0%and 29.3%,respectively,and there were significant differences in the collapse rates among different types(P<0.05).(4)During follow-up,the collapse rates of the femoral head in the first to fifth years were 29.3%,7.9%,4.7%,2.6%and 0.5%,respectively.(5)Results showed that for early non-traumatic osteonecrosis of the femoral head,the risk of collapse of osteonecrosis of the femoral head is high within one year,and the location of the focus of osteonecrosis affects the risk of collapse of the femoral head.The effect of the location of the focus on the prognosis of the disease should be considered in clinical treatment.

17.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1021476

RESUMO

BACKGROUND:For the patients who have undergone unicompartmental knee arthroplasty,although the surgical effect is clear,there is still a lack of effective quantitative evaluation tools,and it is necessary to further explore the early postoperative gait and stability changes. OBJECTIVE:To investigate the changes in gait and stability before and after unicompartmental knee arthroplasty. METHODS:From May 2021 to May 2022,30 patients aged(63.80±9.31)years who planned to perform unilateral unicompartmental knee arthroplasty in the Department of Joint Surgery,Affiliated Hospital of Xuzhou Medical University were selected as the unicompartmental knee arthroplasty group.15 healthy elderly patients aged(61.28±8.60)years without a history of hip and knee pain and hip and knee joint dysfunction were recruited as the control group.Hospital for special surgery scores,stability parameters(center of pressure path length,95%confidence ellipse area)and gait parameters(pace,stride length,stride frequency,gait cycle,and the proportion of single support period)were recorded and compared in the control group and unicompartmental knee arthroplasty group before operation,1 and 3 months after operation. RESULTS AND CONCLUSION:(1)There was no significant difference in the step frequency between the patients 1 month after operation and those before operation in the unicompartmental knee arthroplasty group(P>0.05).The stability of 1 month after operation was worse than that before operation,and other parameters of 1 month after operation were better than those before operation,and the difference was statistically significant(P<0.05).(2)Hospital for special surgery score,gait and stability parameters at 3 months after operation were better than those before operation(P<0.05).(3)Compared with the control group,the pace,stride length,stride frequency,and the proportion of single support period of the unicompartmental knee arthroplasty group were significantly lower before and 3 months after operation.Center of pressure path length,95%confidence ellipse area and gait cycle were greater in the unicompartmental knee arthroplasty group than those in the control group,with statistically significant differences(P<0.05).(4)It is indicated that gait analysis is an effective means to quantitatively evaluate the rehabilitation status after unicompartmental knee arthroplasty.The early gait recovery after unicompartmental knee arthroplasty is good,but the gait frequency improvement is not obvious and the stability is poor 1 month after the operation.

18.
Nat Commun ; 14(1): 7447, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37978192

RESUMO

The atomic-thick anticorrosion coating for copper (Cu) electrodes is essential for the miniaturisation in the semiconductor industry. Graphene has long been expected to be the ultimate anticorrosion material, however, its real anticorrosion performance is still under great controversy. Specifically, strong electronic couplings can limit the interfacial diffusion of corrosive molecules, whereas they can also promote the surficial galvanic corrosion. Here, we report the enhanced anticorrosion for Cu simply via a bilayer graphene coating, which provides protection for more than 5 years at room temperature and 1000 h at 200 °C. Such excellent anticorrosion is attributed to a nontrivial Janus-doping effect in bilayer graphene, where the heavily doped bottom layer forms a strong interaction with Cu to limit the interfacial diffusion, while the nearly charge neutral top layer behaves inertly to alleviate the galvanic corrosion. Our study will likely expand the application scenarios of Cu under various extreme operating conditions.

19.
Chem Commun (Camb) ; 59(92): 13690-13702, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37902025

RESUMO

Phenolic compounds are ubiquitous in nature because of their unique physical and chemical properties and wide applications, which have received extensive research attention. Phenolic compounds represented by tannic acid (TA) play an important role at the nanoscale. TA with a polyphenol hydroxyl structure can chemically react with organic or inorganic materials, among which metal-phenolic networks (MPNs) formed by coordination with metal ions and polyphenol derivatives formed by interactions with organic matter, exhibit specific properties and functions, and play key roles in photo(electro)catalysis. In this paper, we first introduce the fundamental properties of TA, then summarize the factors influencing the properties of MPNs and structural transformation of polyphenol-derived materials. Subsequently, the functions of MPNs and polyphenol derivatives in photo(electro)catalysis reactions are summarized, encompassing improving interfacial charge carrier separation, accelerating surface reaction kinetics, and enhancing light absorption. Finally, this article provides a comprehensive overview of the challenges and outlook associated with MPNs. Additionally, it presents novel insights into their stability, mechanistic analysis, synthesis, and applications in photo(electro)catalysis.

20.
ACS Appl Mater Interfaces ; 15(40): 47111-47124, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37768923

RESUMO

Recently, growing interest in self-powered devices has led to the invention of new energy conversion devices. Photo-thermoelectric generators (PTEGs) have rapidly developed for their ability to harvest both light and thermal energy, but these devices are overly dependent on the continuity of energy input and cannot sustain output in an emergency situation. In the current study, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)/graphene oxide (GO)/graphene nanosheets (GNPs)/polyethylene glycol (PEG) phase-change composites (PCCs) were prepared with freeze-drying and vacuum-filling processes to acquire materials suitable for imparting energy storage characteristics to PTEGs. The melting and crystallization enthalpies of the PCCs fabricated based on the PEDOT:PSS/GO/GNP aerogels can reach 211.5 and 207.6 J g-1, respectively, which increase by nearly 5% compared with pure PEG, and the growth rate of thermal conductivity of the composites is as high as 262.7% (1.12 W m-1 K-1). Meanwhile, the excellent photothermal properties and high-temperature shape stability that pure PEG does not possess can also be imparted to PCCs by the aerogels. The PTEG assembled with PCCs and thermoelectric components can achieve a continuous output of over 1500 s after 300 s of light irradiation. After integrating the output of the device during the lamp on/off period, it is found that the total output of the device during the light-off period (8.4 V and 9.6 mW) can far exceed its total output during the light-on period (2.7 V and 4.4 mW). This work provides guidance for modulating the performance of PCCs and giving PTEGs the ability to operate under emergency or extremely harsh conditions and the prepared PTEGs are highly promising for practical use.

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