Direct Comparative Studies Revealing the Contribution of TADF Activity of Organic Emitters Towards Efficient Electrochemiluminescence.

Electrochemiluminescence (ECL) featuring thermally activated delayed fluorescence (TADF) properties has attracted considerable interest, showcasing their potential for 100% exciton harvesting, which marks a significant advancement in the realm of organic ECL. However, the challenge of elucidating the precise contribution of TADF to the enhanced ECL efficiency arises due to the lack of comparative studies of organic compounds with or without efficient TADF properties. In this study, we present four carbazole-benzonitrile (Cz-BN) molecules possessing similar chemical structures and comparable exchange energy (ΔEST). Despite their comparable properties, these compounds exhibited varying TADF efficiencies, warranting a closer examination of their underlying structural and electronic characteristics governing the optical properties. Consequently, intense ECL emission was only observed from 4CzBN with a remarkable TADF efficiency, underscoring the substantial difference in the ECL signal among molecules with comparable ΔEST and similar spectral properties but varying TADF activity.

A papain-based colorimetric catalytic sensing system for immunoassay detection of carcinoembryonic antigen.

A colorimetric immunoassay was built for determination of carcinoembryonic antigen (CEA) based on papain-based colorimetric catalytic sensing system through the use of glucose oxidase (GOx). In the presence of GOx, glucose was catalytically oxidized to produce H2O2. Through the assistance of papain (as a peroxide mimetic enzyme), the signal came from the oxidative color development of 3,3',5,5'-tetramethylbenzidine (TMB, from colorless to blue) catalyzed by the generated H2O2. Herein, a sandwich-type immunoassay was built based on GOx as labels. As the concentration of CEA increased, more GOx-labeled antibodies specifically associate with target, which leaded to more H2O2 generation. Immediately following this, more TMB were oxidized with the addition of papain. Accordingly, the absorbance increased further. As a result, the concentration of CEA is positively correlated with the change in absorbance of the solution. Under optimal conditions, the CEA concentration was linear in the range of 0.05-20.0 ng/mL, and the limit of detection (LOD) reached 37 pg/mL. The papain-based colorimetric immunoassay also exhibited satisfactory repeatability, stability, and selectivity.

The prognostic nutritional index as a predictor of efficacy and early recurrence for adjuvant transarterial chemoembolization in hepatocellular carcinoma.

BACKGROUND AND AIMS: Postoperative adjuvant transcatheter arterial chemoembolization (TACE) can prevent recurrence of hepatocellular carcinoma (HCC) in certain patients. This study aimed to identify the potential beneficiaries of adjuvant TACE. METHODS: 477 patients who underwent curative resection for HCC were enrolled in this retrospectively cohort study. The trajectory of the prognostic nutritional index (PNI) during the perioperative period was fitted using a latent-class growth mixed model. The association between adjuvant TACE and recurrence-free survival in each PNI group was assessed using the Kaplan-Meier curve. Furthermore, Cox regression analysis was conducted to identify the risk factors for early recurrence after adjuvant TACE and develop a nomogram model. RESULTS: Patients in the PNI group III had a high risk of recurrence and could benefit from adjuvant TACE (P = 0.009). The prognostic prediction model for adjuvant TACE (PAT) incorporated eight variables (PNI, tumor size, tumor number, microvascular invasion, sex, aspartate aminotransferase, gamma-glutamyl transferase, and degree of differentiation). Patients with PAT score >330 and 235-330 had significantly higher recurrence rates than those with PAT score <235 (P < 0.001). CONCLUSION: PNI may help guide the selection of adjuvant TACE beneficiaries. PAT demonstrated a high accuracy in predicting the prognosis of patients who underwent postoperative TACE.

TLR3 activation enhances abscopal effect of radiotherapy in HCC by promoting tumor ferroptosis.

Radiotherapy (RT) has been reported to induce abscopal effect in advanced hepatocellular carcinoma (HCC), but such phenomenon was only observed in sporadic cases. Here, we demonstrated that subcutaneous administration of Toll-like receptor 3 (TLR3) agonist poly(I:C) could strengthen the abscopal effect during RT through activating tumor cell ferroptosis signals in bilateral HCC subcutaneous tumor mouse models, which could be significantly abolished by TLR3 knock-out or ferroptosis inhibitor ferrostatin-1. Moreover, poly(I:C) could promote the presentation of tumor neoantigens by dendritic cells to enhance the recruitment of activated CD8+ T cells into distant tumor tissues for inducing tumor cell ferroptosis during RT treatment. Finally, the safety and feasibility of combining poly(I:C) with RT for treating advanced HCC patients were further verified in a prospective clinical trial. Thus, enhancing TLR3 signaling activation during RT could provide a novel strategy for strengthening abscopal effect to improve the clinical benefits of advanced HCC patients.

Significantly enhanced catalytic performance of Pd nanocatalyst on AlOOH featuring abundant solid surface frustrated Lewis pair for improved hydrogen activation.

The catalytic performance of a catalyst is significantly influenced by its ability to activate hydrogen. Constructing frustrated Lewis pairs (FLPs) with the capacity for hydrogen dissociation on non-reducible supports remains a formidable challenge. Herein, we employed a straightforward method to synthesize a layered AlOOH featuring abundant OH defects suitable for constructing solid surface frustrated Lewis pair (ssFLP). The results indicated that the AlOOH-80 (synthesized at 80 °C) possessed an appropriate crystalline structure conducive to generating numerous OH defects, which facilitated the formation of ssFLP. This was further evidenced by the minimal water adsorption in the AlOOH-80, inversely correlated with the quantity of defects in the catalyst. As expected, the Pd loaded onto AlOOH (Pd/AlOOH-80) exhibited excellent catalytic activity in hydrogenation reactions, attributed to abundant defects available for constructing ssFLP. Remarkably, the Pd/AlOOH-80 catalyst, with larger-sized Pd nanoparticles, displayed notably superior activity compared to commercial Pd/Al2O3 and Pd/C, both featuring smaller-sized Pd nanoparticles. Evidently, under the influence of ssFLP, the size effect of Pd nanoparticles did not dominate, highlighting the pivotal role of ssFLP in enhancing catalytic performance. This catalyst also exhibited exceptionally high stability, indicating its potential for industrial applications.

Optimizing hepatocellular carcinoma disease staging systems by incorporating tumor micronecrosis: A multi-institutional retrospective study.

Tumor micronecrosis is a pathological feature that reflects malignant biological behavior in hepatocellular carcinoma (HCC). However, whether micronecrosis can optimize HCC staging systems remains unilluminated. A total of 1632 HCC patients who underwent curative hepatectomy in four institutions from January 2014 to December 2021 were enrolled in this study. Independent prognostic factors were identified, and optimized staging models were established using a training cohort (n = 934). The performance of optimized staging models was validated using an external cohort consisting of cases from three other institutions (n = 232). In addition, patients from our prospectively collected database (n = 379) tested the application effectiveness of the models. Harrel's c-statistics and the corrected Akaike information criterion (AICc) were used to assess the performance of staging models. In most of Barcelona Clinic Liver Cancer (BCLC) and tumor (T) stages, HCC patients with tumor micronecrosis showed poorer prognosis than those without. Tumor micronecrosis, microvascular invasion, multiple tumors and tumor size >2 cm were independent prognostic-related factors. The BCLC and T staging models incorporating tumor micronecrosis showed better performance than the original systems (c-statistic, 0.712 and 0.711 vs. 0.664 and 0.679; AICc, 2314.8 and 2322.3 vs. 2338.2 and 2338.1; respectively). Furthermore, the external validation cohort confirmed that the optimized staging models had improved efficiency compared with the original ones. Moreover, the prospective cohort demonstrated the applicability of the optimized staging systems. Tumor micronecrosis plays a stage-ascending role in HCC patients. The BCLC and T staging systems incorporating tumor micronecrosis can improve the prognosis stratification efficiency of patients.

Personalized neoantigen vaccine enhances the therapeutic efficacy of bevacizumab and anti-PD-1 antibody in advanced non-small cell lung cancer.

Clinically, a considerable number of non-small cell lung cancer (NSCLC) patients are unable to receive or resist chemotherapy, and the efficacy of non-chemotherapy treatment strategies based on anti-angiogenic agents combined with immune checkpoint blockade is still unsatisfactory. Neoantigen vaccine, based on personalized tumor DNA mutations, could elicit tumor specific T cell infiltration into the tumor site, exerting potent anti-tumor efficacy. Here, we evaluated the feasibility and safety of a new antitumor strategy by adding neoantigen vaccine to the regimen of bevacizumab and anti-PD-1 antibody. Firstly, 7 novel immunogenic neoantigen peptides were identified and developed for neoantigen vaccine (LLCvac), which can elicit strong antitumor immune response in vivo. Then, in orthotopic lung cancer model, LLCvac further combining with bevacizumab and anti-PD-1 antibody exerted a stronger antitumor effect, exhibiting significant decrease of tumor volume without obvious toxicity. Furthermore, tumor immune microenvironment assessment also showed that the proportion of neoantigen-specific T cells in blood could be induced dramatically by the combined therapy. And a large amount of neoantigen-specific Ki67-positive CD8+ T cells were found in tumor tissues, which infiltrated tumor tissues effectively to kill tumor cells expressing identified neoantigens. Overall, these results suggested that this combined therapy could safely induce robust antitumor efficacy, serving as an effective chemotherapy-free strategy for NSCLC treatment.

One-dimensional coordinated polymers of tetraphenylethene pyridine and copper-iodide for fluorescence detection of nitroaromatic explosives.

The spatial arrangement of molecules plays a crucial role in determining the macroscopic properties of functional materials. Coordinated polymers (CPs) formed by self-assembly of organic isomeric ligands and metals offer unique performance characteristics. In this study, we present the investigation of a one-dimensional CP, named CIT-E, composed of tetraphenylethene pyridine derivative (TPE-2by-2-E) ligands and copper iodide. The resulting CP exhibits a one-dimensional bead chain structure with exceptional thermal and chemical stability. By leveraging the competitive absorption between CIT-E and the explosive analog 2,4-dinitroaniline, we achieve detection of the explosive through changes in the absorption intensity of the excitation light source and subsequent fluorescence response. The CP demonstrates high selectivity and anti-interference ability in detecting 2,4-dinitroaniline in aqueous solution, with a detection linear range of 0.1 to 300 µM and a detection limit of 0.05 µM, surpassing the national third-level emission standard. These findings highlight the potential of CP CIT-E as a promising material for the detection of explosive nitroaromatic compounds.

Spleen-targeted neoantigen DNA vaccine for personalized immunotherapy of hepatocellular carcinoma.

Neoantigens are emerging as attractive targets to develop personalized cancer vaccines, but their immunization efficacy is severely hampered by their restricted accessibility to lymphoid tissues where immune responses are initiated. Leveraging the capability of red blood cells (RBCs) to capture and present pathogens in peripheral blood to the antigen-presenting cells (APCs) in spleen, we developed a RBC-driven spleen targeting strategy to deliver DNA vaccine encoding hepatocellular carcinoma (HCC) neoantigen. The DNA vaccine-encapsulating polymeric nanoparticles that were intentionally hitchhiked on the preisolated RBCs could preferentially accumulate in the spleen to promote the neoantigen expression by APCs, resulting in the burst of neoantigen-specific T-cell immunity to prevent tumorigenesis in a personalized manner, and slow down tumor growth in the established aggressively growing HCC. Remarkably, when combined with anti-PD-1, the vaccine achieved complete tumor regression and generated a robust systemic immune response with long-term tumor-specific immunological memory, which thoroughly prevented tumor recurrence and spontaneous lung metastasis. This study offers a prospective strategy to develop personalized neoantigen vaccines for augmenting cancer immunotherapy efficiency in immune "cold" HCC.

Efficient fluorescence-enhanced probe for cyanide ions based on a tetraphenylethene pyridine coordinated copper-iodide complex.

An efficient fluorescence-enhanced probe was developed for detecting cyanide ions (CN-) based on a tetraphenylethene coordinated copper-iodide complex (named CIT-Z). The coordination polymers (CPs) prepared were (Z)-1,2-diphenyl-1,2-bis[4-(pyridin-3-ylmethoxy)phenyl]ethene (1Z) and a CuI cluster, where the tetraphenylethylene (TPE) pyridine derivatives acted as organic ligands and the CuI cluster acted as a metal center. The higher-dimensional CIT-Z exhibited a 3-fold-interpenetrating network structure with excellent optical properties and chemical stability. This study also provides insights into the mechanism behind the fluorescence enhancement, which is attributed to the competitive coordination between CN- and the ligands. The probe showed high selectivity and sensitivity towards CN-, with a detection limit of 0.1 µM and good recovery in the real water samples.

Identification of tumor mutations in plasma based on mutation variant frequency change (MVFC).

To overcome the dependency of strategies utilizing cell-free DNA (cfDNA) on tissue sampling, the emergence of sequencing panels for non-invasive mutation screening was promoted. However, cfDNA sequencing with panels still suffers from either inaccuracy or omission, and novel approaches for accurately screening tumor mutations solely based on plasma without gene panel restriction are urgently needed. We performed unique molecular identifier (UMI) target sequencing on plasma samples and peripheral blood mononuclear cells (PBMCs) from 85 hepatocellular carcinoma (HCC) patients receiving surgical resection, which were divided into an exploration dataset (20 patients) or an evaluation dataset (65 patients). Plasma mutations were identified in pre-operative plasma, and the mutation variant frequency change (MVFC) between post- and pre-operative plasma was then calculated. In the exploration dataset, we observed that plasma mutations with MVFC < 0.2 were enriched for tumor mutations identified in tumor tissues and had frequency changes that correlated with tumor burden; these plasma mutations were therefore defined as MVFC-identified tumor mutations. The presence of MVFC-identified tumor mutations after surgery was related to shorter relapse-free survival (RFS) in both datasets and thus indicated minimum residual disease (MRD). The combination of MVFC-identified tumor mutations and Alpha Fetoprotein (AFP) could further improve MRD detection (P < 0.0001). Identification of tumor mutations based on MVFC was also confirmed to be applicable with a different gene panel. Overall, we proposed a novel strategy for non-invasive tumor mutation screening using solely plasma that could be utilized in HCC tumor-burden monitoring and MRD detection.

Association between physical activity and resistant hypertension in treated hypertension patients: analysis of the national health and nutrition examination survey.

INTRODUCTION: Current guidelines suggest that regular aerobic training might lower blood pressure in hypertensive individuals. However, evidence linking resistant hypertension (RH) with total daily physical activity (PA), including work-, transport-, and recreation-related PA, is limited. Therefore, this study assessed the association between daily PA and RH. METHOD: A cross-sectional study was conducted using data acquired from a nationwide survey in the US (the National Health and Nutrition Examination Survey, NHANES). The weighted prevalence of RH was calculated, and moderate and vigorous daily PA was assessed using the Global Physical Activity Questionnaire (GPAQ). A multivariate logistic regression model determined the association between daily PA and RH. RESULTS: A total of 8,496 treated hypertension patients were identified, including 959 RH cases. The unweighted prevalence of RH among treated hypertension cases was 11.28%, while the weighted prevalence was 9.81%. Participants with RH had a low rate of recommended PA levels (39.83%), and daily PA and RH were significantly associated. PA exhibited significant dose-dependent trends with a low probability of RH (p-trends < 0.05). Additionally, participants with sufficient daily PA had a 14% lower probability of RH than those with insufficient PA [fully adjusted odds ratio (OR) = 0.86; 95% confidence interval (CI) = 0.74-0.99). CONCLUSION: The present study revealed that RH has an incidence of up to 9.81% in treated hypertension patients. Hypertensive patients tended to be physically inactive, and insufficient PA and RH were significantly associated. Sufficient daily PA should be recommended to reduce the RH probability among treated hypertension patients.

Visceral adiposity index and the risk of heart failure, late-life cardiac structure, and function in ARIC study.

BACKGROUND: It is well established that obesity is associated with the risk of heart failure (HF). However, the data about relationship between visceral fat and the risk of HF are limited. AIMS: We aim to evaluate the association between visceral obesity assessed by visceral adiposity index (VAI) and incident HF and left ventricular (LV) structure and function in Atherosclerosis Risk in Communities (ARIC) study. METHODS: We included 12 161 participants (aged 54.1 ± 5.8 years) free of history of HF and coronary heart disease at baseline (1987-89) in ARIC study. We used multivariable Cox hazard regression models to assess the association between the VAI and incident HF. We further explored the effects of the VAI on LV geometry and function among 4817 participants with echocardiographic data using multivariable linear regression analysis and multinomial logistic regression. RESULTS: During a median follow-up of 22.5 years, a total of 1904 (15.7%) participants developed HF. After adjustment for traditional HF risk factors, 1 unit increase in the baseline VAI was associated with an 8% higher risk of incident HF [hazard ratio (HR): 1.08, 95% confidence interval (CI): 1.06-1.11]. Results were similar when participants were categorized by VAI tertiles. Compared with participants in the lowest tertile of VAI, those in the second tertile and third tertile had a greater risk of incident HF [HR (95% CI): 1.19 (1.05-1.34) and 1.42 (1.26-1.61), respectively]. For the analyses of the HF subtypes, the higher VAI was only associated with the risk of HF with preserved ejection fraction, not with HF with reduced ejection fraction. In addition, the greater VAI was associated with worse LV diastolic function and abnormal LV geometry including concentric remodelling, concentric hypertrophy, and eccentric hypertrophy. CONCLUSION: This study shows that higher VAI was independently associated with the increased risk of incident HF and abnormal LV geometry and LV diastolic dysfunction.

We investigated the relationship between visceral adiposity index (VAI) and incident heart failure (HF) in 12 161 participants and further evaluated the possible effect of the VAI on late-life left ventricular (LV) structure and function in 4817 participants who underwent echocardiography examination at Visit 5 in Atherosclerosis Risk in Communities study.Our study found that VAI, a simple alternative indicator of visceral obesity, was positively associated with the risk of HF.Our results shown that VAI was significantly associated with abnormal LV geometry and worse LV diastolic function in late life.

Universal two-dimensional labelled probe-mediated melting curve analysis based on multiplex PCR for rapid typing of Plasmodium in a single closed tube.

Currently, malaria is still one of the major public health problems commonly caused by the four Plasmodium species. The similar symptoms of malaria and the COVID-19 epidemic of fever or fatigue lead to frequent misdiagnosis. The disadvantages of existing detection methods, such as time-consuming, costly, complicated operation, need for experienced technicians, and indistinguishable typing, lead to difficulties in meeting the clinical requirements of rapid, easy, and accurate typing of common Plasmodium species. In this study, we developed and optimized a universal two-dimensional labelled probe-mediated melting curve analysis (UP-MCA) assay based on multiplex and asymmetric PCR for rapid and accurate typing of five Plasmodium species, including novel human Plasmodium, Plasmodium knowlesi (Pk), in a single closed tube following genome extraction. The assay showed a limit of detection (LOD) of 10 copies per reaction and could accurately distinguish Plasmodium species from intra-plasmodium and other pathogens. Additionally, we proposed and validated different methods of fluorescence quenching and tag design for probes that are suitable for UP-MCA assays. Moreover, the clinical performance of the Plasmodium UP-MCA assay using a base-quenched universal probe was evaluated using 226 samples and showed a sensitivity of 100% (164/164) and specificity of 100% (62/62) at a 99% confidence interval, with the microscopy method as the gold standard. In summary, the UP-MCA assay showed excellent sensitivity, specificity, and accuracy for genotyping Plasmodium species spp. Additionally, it facilitates convenient and rapid Plasmodium detection in routine clinical practice and has great potential for clinical translation.

Development and validation of a nomogram for predicting atrial fibrillation in patients with acute heart failure admitted to the ICU: a retrospective cohort study.

INTRODUCTION: Acute heart failure is a serious condition. Atrial fibrillation is the most frequent arrhythmia in patients with acute heart failure. The occurrence of atrial fibrillation in heart failure patients worsens their prognosis and leads to a substantial increase in treatment costs. There is no tool that can effectively predict the onset of atrial fibrillation in patients with acute heart failure in the ICU currently. MATERIALS AND METHODS: We retrospectively analyzed the MIMIC-IV database of patients admitted to the intensive care unit (ICU) for acute heart failure and who were initially sinus rhythm. Data on demographics, comorbidities, laboratory findings, vital signs, and treatment were extracted. The cohort was divided into a training set and a validation set. Variables selected by LASSO regression and multivariate logistic regression in the training set were used to develop a model for predicting the occurrence of atrial fibrillation in acute heart failure in the ICU. A nomogram was drawn and an online calculator was developed. The discrimination and calibration of the model was evaluated. The performance of the model was tested using the validation set. RESULTS: This study included 2342 patients with acute heart failure, 646 of whom developed atrial fibrillation during their ICU stay. Using LASSO and multiple logistic regression, we selected six significant variables: age, prothrombin time, heart rate, use of vasoactive drugs within 24 h, Sequential Organ Failure Assessment (SOFA) score, and Acute Physiology Score (APS) III. The C-index of the model was 0.700 (95% CI 0.672-0.727) and 0.682 (95% CI 0.639-0.725) in the training and validation sets, respectively. The calibration curves also performed well in both sets. CONCLUSION: We developed a simple and effective model for predicting atrial fibrillation in patients with acute heart failure in the ICU.

Targeting VEGF-A/VEGFR2 Y949 Signaling-Mediated Vascular Permeability Alleviates Hypoxic Pulmonary Hypertension.

BACKGROUND: Pulmonary hypertension (PH) is associated with increased expression of VEGF-A (vascular endothelial growth factor A) and its receptor, VEGFR2 (vascular endothelial growth factor 2), but whether and how activation of VEGF-A signal participates in the pathogenesis of PH is unclear. METHODS: VEGF-A/VEGFR2 signal activation and VEGFR2 Y949-dependent vascular leak were investigated in lung samples from patients with PH and mice exposed to hypoxia. To study their mechanistic roles in hypoxic PH, we examined right ventricle systolic pressure, right ventricular hypertrophy, and pulmonary vasculopathy in mutant mice carrying knock-in of phenylalanine that replaced the tyrosine at residual 949 of VEGFR2 (Vefgr2Y949F) and mice with conditional endothelial deletion of Vegfr2 after chronic hypoxia exposure. RESULTS: We show that PH leads to excessive pulmonary vascular leak in both patients and hypoxic mice, and this is because of an overactivated VEGF-A/VEGFR2 Y949 signaling axis. In the context of hypoxic PH, activation of Yes1 and c-Src and subsequent VE-cadherin phosphorylation in endothelial cells are involved in VEGFR2 Y949-induced vascular permeability. Abolishing VEGFR2 Y949 signaling by Vefgr2Y949F point mutation was sufficient to prevent pulmonary vascular permeability and inhibit macrophage infiltration and Rac1 activation in smooth muscle cells under hypoxia exposure, thereby leading to alleviated PH manifestations, including muscularization of distal pulmonary arterioles, elevated right ventricle systolic pressure, and right ventricular hypertrophy. It is important that we found that VEGFR2 Y949 signaling in myeloid cells including macrophages was trivial and dispensable for hypoxia-induced vascular abnormalities and PH. In contrast with selective blockage of VEGFR2 Y949 signaling, disruption of the entire VEGFR2 signaling by conditional endothelial deletion of Vegfr2 promotes the development of PH. CONCLUSIONS: Our results support the notion that VEGF-A/VEGFR2 Y949-dependent vascular permeability is an important determinant in the pathogenesis of PH and might serve as an attractive therapeutic target pathway for this disease.

Dysregulation of global circular RNA abundance regulated by spliceosomes predicts prognosis in hepatocellular carcinoma.

CircRNAs have been reported to play crucial roles in tumor progression and recurrence, showing potential as biomarkers in cancer. However, the global abundance of circRNA and their involvement in hepatocellular carcinoma (HCC) development have not been fully explored. Whole transcriptome sequencing was performed on tumor and peritumor from 60 patients with HCC to quantify the expression of circRNAs, and the global circRNA abundance was calculated by circRNA index (CRI). Gene-set enrichment analysis and weighted gene co-expression network analysis were used to reveal the biological signaling pathways associated with the global circRNA abundance. The correlation between the global circRNA abundance and the infiltration level of CD8+ T cells was explored by immunohistochemical assays. Small interfering RNA was used to knock down the pre-messenger RNA spliceosome in HCC cell lines to verify the regulation of spliceosome in global circRNA abundance. We found that dysregulation of global circRNA abundance in both tumor and peritumor could lead to worse prognosis. The immunohistochemical assay further revealed that the dysregulation of global circRNA abundance in both tumor and peritumor would obstruct the CD8+ T cells from invading into the tumor, which might explain its correlation with HCC prognosis. We also demonstrated that the spliceosome genes were the main factors to regulate the global circRNA abundance in HCC, and these results were also confirmed by knockdown experiments. Conclusion: This study revealed the association between the global circRNA abundance and patients' prognosis and its underlying mechanism.

LDH-assisted growth of FeCo bimetal-MOF nanorods for electrocatalytic oxygen evolution.

Metal-organic frameworks (MOFs) have emerged as alternative OER catalysts due to their easy regulation, such as in situ self-reconstruction from MOFs to metal hydroxides through alkaline hydrolysis. Herein, we demonstrate a facile strategy for the in situ transformation of FeCo layered double hydroxide (FeCo-LDH) nanosheets into 1D spindle-shaped FeCo-MOFs for efficient OER. An optimized electrode of FeCo-MOF on a nickel foam (NF) was achieved by adjusting the addition of organic ligands and the reaction time in the hydrothermal reaction. Based on the unique 1D nanostructure and the cation regulation, the obtained FeCo-MOF exhibits a good catalytic performance toward the OER with a low overpotential of 475 mV at 100 mA cm-2, a small Tafel slope of 121.8 mV dec-1, and high long-term durability. This study provides a facile strategy for preparing bimetal-MOFs as catalysts for efficient OER.

Ratiometric fluorescence sensing of temperature based on perovskite nanocrystals and rhodamine B doped electrospun fibers.

Sensing temperature (T) has gained great attention since T is the most important parameter in daily life, scientific research and industry. A ratiometric fluorescence T sensor is fabricated by doping MAPbBr3 perovskite nanocrystals (PNCs) and rhodamine B (RhB) into a polyacrylonitrile (PAN) matrix and the composite materials are electrospun into optical fibers. The fibers show characteristic emissions at 521 and 587 nm under UV irradiation (λ ex = 365 nm). Both emission intensities gradually increased with elevating T, accompanied with a fluorescence color change from green to yellow. There is a linear relationship between fluorescence intensity ratio (I 521/I 587) and T in the range of 30-45 °C. The T response sensitivity is as high as 4.38% °C-1 at 45 °C.

Green synthesis of highly stable CsPbBr3 perovskite nanocrystals using natural deep eutectic solvents as solvents and surface ligands.

Perovskite nanocrystals (PNCs) have attracted widespread attention as promising materials for the optoelectronic field due to their remarkable photophysical properties and structural tunability. However, their poor stability and the use of toxic organic solvents in the preparation process have severely restricted their practical applications. Herein, a facile, rapid and toxic organic solvent-free synthesis strategy of CsPbBr3 PNCs was developed for the first time via the ligand-assisted reprecipitation (LARP) method using natural deep eutectic solvents (NADESs) as solvents and surface ligands. In this method, the NADESs not only functioned as solvents for green synthesis, but also served simultaneously as surface ligands of CsPbBr3 PNCs to significantly improve their optical properties and stability. The as-synthesized CsPbBr3 PNCs exhibited high photoluminescence quantum yield (PLQY, ∼96.8%), narrow full width at half-maximum (FWHM, ∼18.8 nm) and a high stability that retained 82.9% of PL intensity after 70 days. This work provides a new strategy for the green synthesis of PNCs, which promises feasibility for the industrial large-scale synthesis of high-quality PNCs.