Association between Serum Lactate Dehydrogenase Level and 30-day Mortality in Patients with Intracranial Hemorrhage with Acute Leukemia in the Induction Phase: A Cohort Study.

Objectives This study aimed to identify the association between lactate dehydrogenase (LDH) levels and 30-day mortality in patients with intracranial hemorrhage (ICH) with acute leukemia during the induction phase. Methods This cohort study included patients with acute leukemia with ICH during induction. We evaluated serum LDH levels upon admission. Multivariable Cox regression analyzed the LDH 30-day mortality association. Interaction and stratified analyses based on factors like age, sex, albumin, white blood cell count, hemoglobin level, and platelet count were conducted. Results We selected 91 patients diagnosed with acute leukemia and ICH. The overall 30-day mortality rate was 61.5%, with 56 of the 91 patients succumbing. Among those with LDH levels ≥ 570 U/L, the mortality rate was 74.4% (32 out of 43), which was higher than the 50% mortality rate of the LDH < 570 U/L group (24 out of 48) ( p = 0.017). In our multivariate regression models, the hazard ratios and their corresponding 95% confidence intervals for Log2 and twice the upper limit of normal LDH were 1.27 (1.01, 1.58) and 2.2 (1.05, 4.58), respectively. Interaction analysis revealed no significant interactive effect on the relationship between LDH levels and 30-day mortality. Conclusions Serum LDH level was associated with 30-day mortality, especially in patients with LDH ≥ 570 U/L.

Recent advances in developing modified C14 side chain pleuromutilins as novel antibacterial agents.

Owing to the increasing resistance to most existing antimicrobial drugs, research has shifted towards developing novel antimicrobial agents with mechanisms of action distinct from those of current clinical options. Pleuromutilins are antibiotics known for their distinct mechanism of action, inhibiting bacterial protein synthesis by binding to the peptidyl transferase center of the ribosome. Recent studies have revealed that pleuromutilin derivatives can disrupt bacterial cell membranes, thereby enhancing antibacterial efficacy. Both marketed pleuromutilin derivatives and those in clinical trials have been developed by structurally modifying the pleuromutilin C14 side chain to improve their antimicrobial activity. Therefore, this review aims to review advancement in the chemical structural characteristics, antibacterial activities, and structure-activity relationship studies of pleuromutilins, specifically focusing on modifications made to the C14 side chain in recent years. These findings provide a valuable reference for future research and development of pleuromutilins.

Pathological and imaging features, treatment, and prognosis of primary intraventricular lymphoma: A review of cases from a single center.

Purpose: The purpose of this retrospective study was to analyze the imaging and pathological features, treatment, and prognosis of patients with primary intraventricular lymphomas (PIL) in order to enhance physicians' understanding of the diagnosis and treatment of PIL. Methods: A retrospective analysis was conducted on 13 cases of PIL that were hospitalized in our institution. Clinical and imaging data of the patients were collected and compared with the pathology data to summarize and analyze the qualitative diagnostic value of magnetic resonance (MR) features. Results: Among the enrolled patients, there were nine males and four females, with an average age of (56 ± 9.0) years. The major clinical features observed in PIL patients were headache and dizziness. All 13 patients underwent plain and contrast-enhanced MR scans, revealing multiple foci in 7 cases and single foci in 6 cases. The lesions were located in the lateral ventricle in 10 cases, the third ventricle in 4 cases, and the fourth ventricle in 4 cases. Plain MR scans demonstrated an isointense or slightly hypointense signal on T1-weighted imaging (T1WI) and an isointense or slightly hyperintense signal on T2-weighted imaging (T2WI). Contrast-enhanced scans showed uniform and consistent enhancement of the tumors. Surgical treatment was performed in all patients, and postoperative pathology confirmed the presence of diffuse large B-cell lymphoma. Conclusions: PIL exhibits specific imaging and pathological features, with diffuse large B-cell lymphoma being the main pathological type. Pathological examination and immunophenotype analysis serve as the gold standards for PIL diagnosis.

Value of neutrophil-to-lymphocyte ratio in neuronal intranuclear inclusion disease.

Background and objectives: The neutrophil-to-lymphocyte ratio (NLR) is a widely recognized marker of inflammation in peripheral blood. However, its specific role in neuronal intranuclear inclusion disease (NIID) has not been reported. This study aims to investigate the relationship between NIID and NLR. Methods: A multicenter database was collected, including 157 NIID patients from seven hospitals (The Affiliated Hospital of Xuzhou Medical University, Yantai Yuhuangding Hospital, Tengzhou Central People's Hospital,The Affiliated Brain Hospital of Nanjing Medical University, Liaocheng People's Hospital,The Second Hospital of Shandong University, Inner Mongolia People's Hospital, Xuanwu Hospital Capital Medical University,The First Affiliated Hospital of USTC), along with 157 age- and gender-matched healthy control subjects. White blood cell counts (including neutrophils, lymphocytes, monocytes, eosinophils, and basophils) were obtained, and the NLR was calculated. Additionally, cognitive impairment was assessed using clinical evaluation scores. Results: NIID patients exhibited significantly higher NLR values compared to the healthy control group (p < 0.001). The plasma NLR levels in NIID patients showed a weak positive correlation with disease duration (r = 0.219, p = 0.016). However, no significant correlations were found between NLR and age of onset or cognitive impairment (p > 0.05). Conclusion: There is a significant association between NLR and NIID, suggesting a potential role of peripheral blood inflammation in the pathogenesis of NIID.

Role of miRNA in pathogenesis, diagnosis, and prognosis in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common cancers and is responsible for the second cancer-related death globally. Many treatment regimens have been developed to cure the disease; however, life expectancy is still low. Therefore, there is an urgent need to explore new selective, specific, and robust diagnosis markers for efficient early recognition of the ailment. Along with the diagnosis, the treatment's effectiveness can be determined by prognostic markers, and miRNAs are excellent tools for the diagnosis and prognosis of HCC. In addition, the altered expression profile of a few miRNAs promotes HCC cell migration and invasion, and selective up- or downregulation of these responsible genes may help mitigate the disorder. On one hand, few of the miRNAs have been found to enhance angiogenesis, a crucial step of tumor growth; on the other hand, upregulation of specific miRNAs is reported to suppress angiogenesis and resulting tumor growth of HCC cells. Exosomal miRNAs have significant implications in promoting angiogenesis, increased endothelial cell permeability, tube formation, and metastasis to hepatic and pulmonary tissues. miRNA also attributes to drug resistance toward chemotherapy and the prevention of autophagy also. Identifying novel miRNA and determining their differential expression in HCC tissue may serve as a potential tool for diagnosis, prognosis, and therapy to enhance the life expectancy and quality of life of HCC patients. In the present review, we have summarized the recent advances in HCC-related research.

Six-year clinical evaluation of iRoot BP Plus as apical barrier in permanent teeth of periapical periodontitis.

The apical barrier technique in permanent teeth with extensive destruction of the periapical tissue and a long infection time is much more difficult to succeed, which is a clinical challenge. This study aimed to evaluate the long-term effects of iRoot BP Plus as an apical material in adult teeth. Fifty incisors and premolars were chosen for this study. All teeth were performed apical barrier with the same operator. After treatment, the teeth were clinically and radiographically evaluated at 1, 2 and 6 years. At the 1-year follow-up, 35 teeth had healed, and three patients developed an apical abscess due to root fracture at the 2-year follow-up. Six years postoperatively, one tooth showed root resorption, which was considered a failure. The long clinical evaluation confirmed that iRoot BP Plus is a suitable material for the apical barrier of mature teeth with open apices and periapical lesions.

HycDemux: a hybrid unsupervised approach for accurate barcoded sample demultiplexing in nanopore sequencing.

DNA barcodes enable Oxford Nanopore sequencing to sequence multiple barcoded DNA samples on a single flow cell. DNA sequences with the same barcode need to be grouped together through demultiplexing. As the number of samples increases, accurate demultiplexing becomes difficult. We introduce HycDemux, which incorporates a GPU-parallelized hybrid clustering algorithm that uses nanopore signals and DNA sequences for accurate data clustering, alongside a voting-based module to finalize the demultiplexing results. Comprehensive experiments demonstrate that our approach outperforms unsupervised tools in short sequence fragment clustering and performs more robustly than current state-of-the-art demultiplexing tools for complex multi-sample sequencing data.

Development of a novel immune infiltration-related diagnostic model for Alzheimer's disease using bioinformatic strategies.

Background: The pathogenesis of Alzheimer's disease (AD) is complex and multi-factorial. Increasing evidence has shown the important role of immune infiltration in AD. Thus the current study was designed to identify immune infiltration-related genes and to explore their diagnostic value in AD. Methods: The expression data of AD patients were downloaded from the GEO database. The limma R package identified differentially expressed genes (DEGs) between AD and controls. The CIBERSORT algorithm identified differentially infiltrated immune cells (DIICs) between AD and controls. DIIC-correlated DEGs were obtained by Pearson correlation analysis. WGCNA was employed to identify DIIC-related modules. Next, LASSO, RFE, and RF machine learning methods were applied to screen robust DIIC-related gene signatures in AD, followed by the construction and validation of a diagnostic nomogram. Detection of the expression of related genes in the peripheral blood of Alzheimer's disease and healthy volunteers by RT-PCR. In addition, the CTD database predicted chemicals targeting DIIC-related gene signatures in the treatment of AD. Results: NK cells, M0 macrophages, activated myeloid dendritic cells, resting mast cells, CD8+ T cells, resting memory CD4+ T cells, gamma delta T cells, and M2 macrophages were differentially infiltrated between AD and controls. Pearson analysis identified a total of 277 DIIC-correlated DEGs between AD and controls. Thereafter, 177 DIIC-related genes were further obtained by WGCNA analysis. By LASSO, RFE and RF algorithms, CMTM2, DDIT4, LDHB, NDUFA1, NDUFB2, NDUFS5, RPL17, RPL21, RPL26 and NDUFAF2 were identified as robust gene signature in AD. The results of RT-PCR detection of peripheral blood samples from Alzheimer's disease and healthy volunteers showed that the expression trend of ten genes screened was consistent with the detection results; among them, the expression levels of CMTM2, DDIT4, LDHB, NDUFS5, and RPL21 are significantly different among groups. Thus, a diagnostic nomogram based on a DIIC-related signature was constructed and validated. Moreover, candidate chemicals targeting those biomarkers in the treatment of AD, such as 4-hydroxy-2-nonenal, rosiglitazone, and resveratrol, were identified in the CTD database. Conclusion: For the first time, we identified 10 immune infiltration-related biomarkers in AD, which may be helpful for the diagnosis of AD and provide guidance in the treatment of AD.

Redox Electrolytes-Assisting Aqueous Zn-Based Batteries by Pseudocapacitive Multiple Perovskite Fluorides Cathode and Charge Storage Mechanisms.

Aqueous Zn-based batteries (AZBs) have attracted intensive attention. However, to explore advanced cathode materials with in-depth elucidation of their charge storage mechanisms, improve energy storage capacity, and construct novel cell systems remain a great challenge. Herein, a new pseudocapacitive multiple perovskite fluorides (ABF3 ) cathode is designed, represented by KMF-(IV, V, and VI; M = NiCoMnZn/-Mg/-MgFe), and constructed Zn//KMF-(IV, V, and VI) AZBs and their flexible devices. Ex situ tests have revealed a typical bulk phase conversion mechanism of KMF-VI electrode for charge storage in alkaline media dominated by redox-active Ni/Co/Mn species, with transformation of ABF3 nanocrystals into amorphous metal oxide/(oxy)hydroxide nanosheets. By employing single or bipolar redox electrolyte strategies of 20 mm [Fe(CN)6 ]3- or/and 10 mm SO3 2- /Cu[(NH3 )4 ]2+ acting on KMF-(IV, V, and VI) cathode and Zn anode, the AZBs show an improved energy storage owing to additional capacity contribution of redox electrolytes. The as-designed Zn//polyvinyl alcohol (PVA)-KOH-K3 [Fe(CN)6 ]//KMF-(IV, V, and VI) redox gel electrolytes-assisting flexible AZBs (RGE-FAZBs) exhibit remarkable performance under different bending angles because of slight dissolution corrosion of zinc anode compared with liquid electrolytes. Overall, the work demonstrates the novel idea of conversion-type multiple ABF3 cathode for redox electrolytes-assisting AZBs (RE-AZBs) and their flexible systems, showing great significance on electrochemical energy storage.

Coupling Dual-phased nickel selenides with N-doped carbon enables efficient urea electrocatalytic oxidation.

Electrochemical urea oxidation reaction (UOR) is urgently in demand for diverse energy conversion and storage device coupled with pollution treatment because of its favorable thermodynamic potential (0.37 V vs RHE) and wide distribution nature of urea, but simultaneously gravely limited by the sluggish reaction dynamics and poisoning of catalyst. Herein, dual-phased Ni0.85Se/NiSe2 coupling with N doped carbon (Ni0.85Se/NiSe2@NC-2) in situ is prepared by a solvothermal-selenization pathway. Benefiting from the collective promotion of the dual-phased composition and the NC support, Ni0.85Se/NiSe2@NC provides abundant active sites, enhanced electrical conductivity. It delivers a current density of 252 mA cm-2 at 1.6 V vs RHE with a small Tafel slop of 64.4 mV dec-1 and gets a lower reaction barrier. Moreover, it requires a cell voltage of 1.46 V to approach 50 mA cm-2, about 250 mV less than that of water electrolysis, confirming the less energy consumption. Notably, the N doped carbon protects Ni0.85Se/NiSe2 nanocrystals from aggregation leading to a faster CO2 desorption from Ni sites, which endow the Ni0.85Se/NiSe2@NC-2 a much better working stability. The direct urea hydrogen peroxide fuel cell (DUHPFC) achieves a maximum power density of 9.09 mW cm-2 at 20 °C. This work extends highly efficient dual-phased structure loading in NC catalysts system for urea-assisted energy conversion.

Promising Neutrophil-Associated Biomarkers in Lung Diseases of Patients with Antisynthetase Syndrome and Dermatomyositis.

Objectives: Antisynthetase syndrome (ASS) and dermatomyositis (DM) are serious autoimmune diseases, with lungs being the most frequently involved organ and sometimes fatal. This study is aimed at clarifying the role of neutrophil-associated biological markers in suggesting ASS and DM-associated respiratory infections and interstitial lung diseases. Methods: We carried out a retrospective review of the medical records of 46 cases of ASS and DM diagnosed at the Second Hospital of Zhejiang University College of Medicine, between January 2017 and December 2020. Serum myeloperoxidase (MPO), neutrophil elastase (NE), α1 anti-trypsin (AAT), and interleukin-6 (IL-6) were also detected. Results: Gottron's sign is characteristic of dermatomyositis, while polyarthritis is more characteristic of ASS. Pulmonary function is worse in ASS than in DM patients. Patients with ASS and DM had abnormal lymphocyte and neutrophil counts compared to healthy subjects, but not in relation to lung function and rapid progression of interstitial lung disease (RP-ILD). Elevated serum NE, MPO, and IL-6 levels are suggestive of respiratory infections, whereas decreased circulating IL-6 is predictive of RP-ILD. Conclusion: Our study identified the neutrophil-associated biomarkers MPO, NE, and IL-6 as promising indicators with different suggestive roles in respiratory infections and interstitial lung diseases in patients with ASS and DM.

Clinical characteristics and prognostic factors in intracranial hemorrhage patients with hematological diseases.

The clinical characteristics and prognosis of intracranial hemorrhage (ICH) in patients with hematological diseases remain controversial. This study aimed to describe the clinical characteristics and explore the prognostic factors in such patients. A total of 238 ICH patients with a hematological disease were recruited from the Institute of Hematology and Blood Diseases Hospital, China, from January 2015 to April 2020. The Cox proportional hazards model was used to identify the prognostic factors for 30-day mortality in ICH patients with a hematological disease. There were 123 cases of acute leukemia (AL), 20 of myelodysplasia/myeloproliferative neoplasm, 35 of aplastic anemia (AA), 29 of immune thrombocytopenia (ITP), 19 of congenital/acquired coagulation factor deficiency, and 12 of other hematological diseases. Furthermore, 121 patients presented with a multi-site hemorrhage (MSH), 58 with a single-site hemorrhage in the brain parenchyma (PCH), 23 with a subarachnoid hemorrhage, 33 with a subdural hemorrhage (SH), and three with an epidural hemorrhage. The Cox proportional hazards model indicated association of SH (vs PCH, hazard ratio [HR]: 0.230; 95% confidence interval [CI]: 0.053-0.996; P = 0.049), low white blood cells (≤ 100 × 109/L vs > 100 × 109/L, HR: 0.56; 95% CI: 0.348-0.910; P = 0.019), AA (vs AL, HR: 0.408; 95% CI: 0.203-0.821; P = 0.012), and ITP (vs AL, HR: 0.197; 95% CI: 0.061-0.640; P = 0.007) with improved 30-day mortality. However, increased age (HR: 1.012; 95% CI: 1.001-1.022; P = 0.034), MSH (vs PCH, HR: 1.891; 95% CI: 1.147-3.117; P = 0.012), and a disturbance of consciousness (HR: 1.989; 95% CI: 1.269-3.117; P = 0.003) were associated with increased risk of 30-day mortality. In conclusion, in this study, we revealed the clinical characteristics of Chinese ICH patients with a hematological disease. Moreover, we identified risk factors (age, white blood cells, AA, ITP, SH, MSH, and a disturbance of consciousness) that may influence 30-day mortality.

Ethynyl and Furyl Functionalized Porphyrin Complexes as New Organic Cathodes Enabling High Power Density and Long-Term Cycling Stability.

Organic cathode materials have recently attracted abundant attention due to their flexible structural tunability and recyclability. However, the low intrinsic electrical conductivity and high solubility in electrolytes of organic electrode materials have significantly limited their practical application. Herein, we present [5,15-bis(ethynyl)-10,20-difurylporphinato] copper(II) (CuDEOP) as a new cathode for rechargeable organic lithium batteries (ROLBs). The combination of both ethynyl and furyl groups of the CuDEOP cathode with a nanorod structure renders it with enhanced structural stability and an extended delocalized π-electron system to deliver excellent cycling stability (capacity retention of 76% after 6000 cycles) and a high power density (16 kW kg-1). The furyl electroactive groups participate in charge storage contribution to achieve a reversible six-electron-transfer redox reaction in a specific voltage range. The mechanism characterizations indicate that the nitrogen atoms on the porphyrin ring act as active sites to alternatively store both PF6- anions and Li+ cations, and the charge storage process is a pseudocapacitive-dominated reaction. This observation will offer a new avenue for designing functionalized molecules for electrochemical energy-storage (EES) systems.

Quenching-induced interfacial amorphous layer containing atomic Ag on Fe2O3 nanosphere for high-performance lithium-ion batteries and mechanism.

The interfacial effect of nanomaterials plays a key role in their electrochemical performance when used in lithium-ion batteries (LIBs), but interfacial modification is a big challenging. Herein, a composite Fe2O3 nanoparticles with atomic Ag/amorphous layers were successfully prepared by co-deposition and subsequent quenching method. Compared to pristine Fe2O3, it maintains a higher capacity and longer cycle life in LIBs, with a capacity of 1150 mAh g-1 after 600 cycles at 0.5 Ag-1, and a long 1800 cycles at a current density of 5 Ag-1 after activation. Detailed experiments and Ex-situ TEM demonstrate that the fusion of surface particles occurred after calcination and quenching treatment, resulting in amorphous layers. The amorphous layer can act as a stabilizer during cycling, which protects the overall nanospheres structure from collapsing and thus leads to ultra-long cycling life. Our findings shed light on the surface modification of nanoscale materials and provides a manner to enhance the electrochemical performance of nanomaterials for LIBs.

Continuous Production of Human Epidermal Growth Factor Using Escherichia coli Biofilm.

Increasing demand for recombinant proteins necessitates efficient protein production processes. In this study, a continuous process for human epidermal growth factor (hEGF) secretion by Escherichia coli was developed by taking advantage of biofilm formation. Genes bcsB, fimH, and csgAcsgB that have proved to facilitate biofilm formation and some genes moaE, yceA, ychJ, and gshB potentially involved in biofilm formation were examined for their effects on hEGF secretion as well as biofilm formation. Finally, biofilm-based fermentation processes were established, which demonstrated the feasibility of continuous production of hEGF with improved efficiency. The best result was obtained from ychJ-disruption that showed a 28% increase in hEGF secretion over the BL21(DE3) wild strain, from 24 to 32 mg/L. Overexpression of bcsB also showed great potential in continuous immobilized fermentation. Overall, the biofilm engineering here represents an effective strategy to improve hEGF production and can be adapted to produce more recombinant proteins in future.

Effect of Acupoint Hot Compress on Postpartum Urinary Retention After Vaginal Delivery: A Randomized Clinical Trial.

Importance: Acupoint hot compress during the early postpartum period may benefit patients after a vaginal delivery, but the evidence of this effect is limited. Objective: To assess whether acupoint hot compress involving the abdominal, lumbosacral, and plantar regions could reduce the incidence of postpartum urinary retention, relieve postpartum uterine contraction pain, prevent emotional disorders, and promote lactation. Design, Setting, and Participants: This multicenter randomized clinical trial was conducted at 12 hospitals in China. Pregnant patients were screened for eligibility (n = 13 949) and enrolled after vaginal delivery (n = 1200) between January 17 and August 15, 2021; data collection was completed on August 18, 2021. After vaginal delivery, these participants were randomized 1:1 to either the intervention group or control group. Statistical analysis was based on per-protocol population. Interventions: Participants in the control group received routine postpartum care. Participants in the intervention group received routine postpartum care plus 3 sessions of a 4-hour acupoint hot compress involving the abdominal, lumbosacral, and plantar regions within 30 minutes, 24 hours, and 48 hours after delivery. Main Outcomes and Measures: The primary outcome was the incidence of postpartum urinary retention, defined as the first urination occurring more than 6.5 hours after delivery and/or use of an indwelling catheter within 72 hours after delivery. The secondary outcomes were postpartum uterine contraction pain intensity (assessed with the visual analog scale [VAS]), depressive symptoms (assessed with the Edinburgh Postnatal Depression Scale), and lactation conditions (including lactation initiation time, breastfeeding milk volume, feeding mood and times, and newborn weight). Results: Of the 1200 participants randomized, 1085 completed the study (537 in the intervention group and 548 in the control group, with a median [IQR] age of 26.0 [24.0-29.0] years). Participants in the intervention group compared with the control group had significantly decreased incidence of postpartum urinary retention (relative risk [RR], 0.58; 95% CI, 0.35-0.98; P = .03); improved postpartum uterine contraction pain when measured at 6.5 hours (median [IQR] VAS score, 1 [1-2] vs 2 [1-2]; P < .001), 28.5 hours (median [IQR] VAS score, 1 [0-1] vs 1 [1-2]; P < .001), 52.5 hours (median [IQR] VAS score, 1 [0-1] vs 1 [0-1]; P < .001), and 76.5 hours (median [IQR] VAS score, 0 [0-1] vs 0 [0-1]; P = .01) after delivery; reduced depressive symptoms (RR, 0.73; 95% CI, 0.54-0.98; P = .01); and increased breastfeeding milk volume measured at 28.5, 52.5, and 76.5 hours after delivery. No adverse events occurred in either of the 2 groups. Conclusions and Relevance: Results of this trial showed that acupoint hot compress after vaginal delivery decreased postpartum urinary retention, uterine contraction pain, and depressive symptoms and increased breastfeeding milk volume. Acupoint hot compress may be considered as an adjunctive intervention in postnatal care that meets patient self-care needs. Trial Registration: Chinese Clinical Trial Registry Identifier: ChiCTR2000038417.

Phase and crystallinity regulations of Ni(OH)2 by vanadium doping boost electrocatalytic urea oxidation reaction.

Direct urea fuel cell (DUFC) and overall urea splitting system have attracted considerable attention as promising choice for energy conversion. Whereas, the anodic half reaction of electrocatalytic urea oxidation reaction (UOR) in these systems awfully limited their practical application due to the complex 6-electron transfer process. Herein, vanadium doped nickel (V-Ni(OH)2) with highly efficient electrocatalytic activity toward UOR was developed by a simple coprecipitation method. The introducing of V not only promotes the phase transforming from inactive ß-Ni(OH)2 to highly active α-Ni(OH)2, but also simultaneously modulates the electron environment of Ni, facilitating high valence species Ni3+ generation in low overpotential, enhancing the electrocatalytic activity potent of each Ni3+ site and speeding up the electrocatalytic reaction. The optimal V-Ni(OH)2 catalyst exhibits a summit current density of 241 mA cm-2 at 1.6 V vs. RHE, a Tafel slope of 32.15 mV dec-1, outperforming ß-Ni(OH)2 and most catalysts that tested on glassy carbon electrode. Furthermore, the assembled direct urea hydrogen peroxide fuel cell (DUPFC) offers a maximum power density of 13.4 mW cm-2 at 20 °C. This work provides an example of combing phase-regulation and electron modulation method for effective UOR electrocatalysts design.

F-decoration-induced partially amorphization of nickel iron layered double hydroxides for high efficiency urea oxidation reaction.

The urea oxidation reaction (UOR) has been well-acknowledged as one of the promising alternatives for hydrogen production through electrochemical water splitting system because of the more favorable thermodynamic potential. But the shortage of cost-effective electrocatalysts with high catalytic activity and durability restricts its practical development. Herein, the partially amorphous fluorine-decorated nickel iron layered double hydroxides (NiFe-F) is constructed via a low-temperature fluoridation method. Our study found that HF acid etching of NiFe LDH precursor resulted in the partially amorphous feature and abundant oxygen vacancies, providing rich reaction sites. Simultaneously, the formation of ionic metal-F bond makes it easier to form high-valence metal oxygen hydroxide active sites. Specifically, the as-prepared NiFe-F-4 electrode demonstrates a superb mass activity of 1290 mA mg-1 at 1.6 V vs. RHE. Further experiments found that amorphous structure and F decorating decreased the activation energy of UOR from 30.71 kJ mol-1 (crystalline NiFe-F-4) to 20.17 kJ mol-1 (amorphous NiFe-F-4), leading to a rapid dynamic with a small Tafel slope of 31 mV dec-1. Moreover, NiFe-F-4 casts remarkable long-term durability for 40 h without performance decay. This work holds great promise to develop advanced electrocatalysts for pollution treatment of urea-rich wastewater and energy-saving H2 production.