Tandem Acidic CO2 Electrolysis Coupled with Syngas Fermentation: A Two-Stage Process for Producing Medium-Chain Fatty Acids.

The tandem application of CO2 electrolysis with syngas fermentation holds promise for achieving heightened production rates and improved product quality. However, the significant impact of syngas composition on mixed culture-based microbial chain elongation remains unclear. Additionally, effective methods for generating syngas with an adjustable composition from acidic CO2 electrolysis are currently lacking. This study successfully demonstrated the production of medium-chain fatty acids from CO2 through tandem acidic electrolysis with syngas fermentation. CO could serve as the sole energy source or as the electron donor (when cofed with acetate) for caproate generation. Furthermore, the results of gas diffusion electrode structure engineering highlighted that the use of carbon black, either alone or in combination with graphite, enabled consistent syngas generation with an adjustable composition from acidic CO2 electrolysis (pH 1). The carbon black layer significantly improved the CO selectivity, increasing from 0% to 43.5% (0.05 M K+) and further to 92.4% (0.5 M K+). This enhancement in performance was attributed to the promotion of K+ accumulation, stabilizing catalytically active sites, rather than creating a localized alkaline environment for CO2-to-CO conversion. This research contributes to the advancement of hybrid technology for sustainable CO2 reduction and chemical production.

Refining microbial potentiometric sensor performance with unique cathodic catalytic properties for targeted application scenarios.

Traditional microbial electrochemical sensors encounter challenges due to their inherent complexity. In response to these challenges, the microbial potentiometric sensor (MPS) technology was introduced, featuring a straightforward high-impedance measurement circuit tailored for environmental monitoring. Nonetheless, the practical implementation of conventional MPS is constrained by issues such as the exposure of the reference electrode to the monitored water and the absence of methodologies to stimulate microbial metabolism. In this study, our objective was to enhance MPS performance by imbuing it with unique cathodic catalytic properties, specifically tailored for distinct application scenarios. Notably, the anodic region served as the sensing element, with both the cathodic region and reference electrode physically isolated from the analyzed water sample. In the realm of organic monitoring, the sensor without Pt/C coated in the cathodic region exhibited a faster response time (1 h) and lower detection limits (1 mg L-1 BOD, 1 mM acetic acid). Conversely, when monitoring toxic substances, the sensor with Pt/C showcased a lower detection limit (0.004% formaldehyde), while the Pt/C-free sensor demonstrated superior reusability. The sensor with Pt/C displayed a heightened anode biofilm thickness and coverage, predominantly composed of Rhodococcus. In conclusion, this study introduces simple, cost-effective, and tailorable biosensors holding substantial promise for water quality monitoring.

Contribution of individual and cumulative social determinants of health underlying gender disparities in periodontitis in a representative US population: A cross-sectional NHANES study.

AIM: To examine the impact of both individual and cumulative social determinants of health (SDoH) on the likelihood of developing periodontitis, while also exploring any gender disparities in this relationship. MATERIALS AND METHODS: Data of self-reported SDoH domains and sub-items based on Healthy People 2030 were obtained from the U.S. National Health and Nutrition Examination Surveys between 1999 and 2014. Logistic regression models, weighted by survey responses, were used to examine the relationship between SDoH (including eight sub-items and the cumulative number of unfavourable SDoH) and periodontitis. The results were further analysed by gender. RESULTS: A total of 18,075 participants (8867 males and 9208 females) were included in the main analysis, of which 5814 (32.2%) had periodontitis. The study found that certain unfavourable SDoH were individually associated with higher odds of periodontitis, and the cumulative number of unfavourable SDoH was positively linked to the odds of developing periodontitis. Furthermore, males exposed to more unfavourable SDoH appeared to be more susceptible to developing periodontitis than females. CONCLUSIONS: The findings suggest that unfavourable SDoH, especially when they accumulate, are associated with an increased odds of periodontitis and contribute to gender disparities within the U.S.

Outdoor gardening activity with different frequency and duration may be associated with reduction of total and cause-specific mortality risk for general U.S. adults: Findings from the NHANES.

BACKGROUND AND AIMS: Engaging in recommended levels of physical activity (PA) is associated with reduced overall and cause-specific mortality rates. Our study aims to examine the relationship between gardening-specific PA and all-cause and cause-specific mortality based on representative U.S. adults. METHODS AND RESULTS: A total of 13,812 adults representing 663.5 million non-institutionalized U.S. adults were included in the National Health and Nutrition Examination Survey. Self-reported gardening activity (GA) was assessed by a validated questionnaire, and outcomes of interest were all-cause mortality and mortality specific to certain causes. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using survey-multivariable Cox proportional hazards models. During a median follow-up period of 16.8 years (Interquartile range = 14.8-18.7), there were 3,476 deaths. After adjusting for potential covariates, we found that participants exposed to GA were more likely to have a lower risk of total mortality [HR (95% CI): 0.76 (0.68, 0.85), P-value < 0.001], cancer-specific mortality [HR (95% CI): 0.81 (0.67, 0.99), P-value < 0.05], cardiovascular disease mortality [HR (95% CI): 0.65 (0.53, 0.80), P-value < 0.001], and respiratory disease mortality [HR (95% CI): 0.66 (0.45, 0.98), P-value < 0.05], compared to those without GA exposure. Furthermore, engaging in GA more frequently and for longer durations was significantly associated with a lower total mortality risk. CONCLUSION: Our study provides evidence that engaging in GA is associated with a decreased risk of overall and cause-specific mortality. However, further longitudinal or interventional studies are needed to investigate the potential benefits of GA.

Correlation between CT images of lateral plateau and lateral meniscus injuries in patients with Schatzker II tibial plateau fractures:a retrospective study.

BACKGROUND: There is a great deal of controversy on whether routine MRI examination is needed for fresh fractures while the vast majority of patients with tibial plateau fractures (TPFs) receive preoperative X-ray and CT examinations. The purpose of the study was to analyze the exact correlation between CT images of lateral plateau and lateral meniscus injuries in Schatzker II TPFs. METHODS: A total of 296 patients with Schatzker II TPFs from August 2012 to January 2021 in two trauma centers were enrolled for the analysis. According to the actual situation during open reduction internal fixation (ORIF) and knee arthroscopic surgery, patients were divided into meniscus injury (including rupture, incarceration, etc.) and non-meniscus injury groups. The values of both lateral plateau depression (LPD) and lateral plateau widening (LPW) of lateral tibial plateau on CT images were measured, and their correlation with lateral meniscus injury was then analyzed. The relevant receiver operating characteristic (ROC) curve was drawn to evaluate the optimal cut-off point of the two indicators which could predict meniscus injury. RESULTS: The intra- and inter-observer reliabilities of LPD and LPW were acceptable (intraclass correlation coefficient (ICC) > 0.8). The average LPD was 13.2 ± 3.2 mm while the average value of the group without meniscus injury was 9.4 ± 3.2 mm. The difference between the two groups was statistically significant (P < 0.05). The average LPW was 8.0 ± 1.4 mm and 6.8 ± 1.6 mm in meniscus injury and non-meniscus injury groups with a significant difference (P < 0.05). The optimal predictive cut-off value of LPD and LPW was 7.9 mm (sensitivity-95.0%, specificity-58.8%, area under the curve (AUC-0.818) and 7.5 mm (sensitivity-70.0%, specificity - 70.6%, AUC - 0.724), respectively. The meniscus injury group mainly showed injuries involving the mid-body and posterior horn of lateral meniscus (98.1%, 157/160). CONCLUSIONS: The mid-body and posterior horn of lateral meniscus injury is more likely to occur in patients with Schatzker II TPFs when LPD > 7.9 mm and/or LPW > 7.5 mm on CT. These findings will definitely provide guidance for orthopedic surgeons in treating such injuries. During the operation, more attention is required be paid to the treatment of the meniscus and the possible fracture reduction difficulties and poor alignment caused by meniscus rupture and incarceration should be fully considered in order to achieve better surgical results.

Preliminary experience with 3D digital image microscope system on the treatment of varicocele.

The three-dimension digital image microscope system (3D-DIM) with a better ergonomic design and equipment characteristics can contribute to the achievement of good results during microsurgery. In this study, the safety and efficiency of 3D-DIM assisted varicocelectomy was evaluated. From July 2019 to November 2019, fifteen cases with varicocele (20 sides of varicocele in total) were included, seven cases underwent 3D-DIM-assisted modified microsurgical subinguinal varicocelectomy, and eight cases underwent modified microsurgical subinguinal varicocelectomy under standard operating microscope (SOM). The mean operative time of 3D-DIM group (67 ± 12.3 min) was a little longer than that of SOM group (55 ± 12.9 min) (p < 0.05). There was no significant difference between the two groups in the number of internal spermatic arteries, internal spermatic vein, lymphatics, gubernacular vein, external spermatic vein and post-operation complications. The 3D-DIM showed a significant difference in image definition for nurse (p < 0.01) and in doctor-nurse cooperation (p < 0.05) over SOM. The 3D-DIM with better ergonomic design and image definition can be applied to perform microsurgical subinguinal varicocelectomy, and could improve the surgeon's fatigue and doctor-nurse cooperation. We believe that the 3D-DIM would be widely used in the field of male infertility microsurgery in the near future.

CD36 as a Molecular Target of Functional DNA Aptamer NAFLD01 Selected against NAFLD Cells.

The aim of this study was to identify the target of nonalcoholic fatty liver disease (NAFLD) cell-specific aptamer NAFLD01 and investigate its effect on lipid metabolism in vitro. A distinct membrane protein of NAFLD cells pulled down by NAFLD01 was analyzed by mass spectrometry to determine target candidates, and affinity of NAFLD01 to target-protein-silent NAFLD cells was detected to validate it. Knockdown of CD36 abolished the binding of NAFLD01, and its binding affinity was associated with membrane-bound CD36. NAFLD01 affinity for NAFLD cells was proportional to the CD36 expression level. Moreover, compared to random sequences, NAFLD01 showed better recognition for both mouse and human tissue sections of NAFLD. Importantly, NAFLD01 could ameliorate liver fat deposition through interaction with CD36 in vitro. Therefore, aptamer NAFLD01 could act as an effective and safe targeted drug for NAFLD. NAFLD01 is the first reported CD36-specific aptamer. This aptamer can improve hepatocyte steatosis via specifically binding to CD36. This study provides a molecular tool to investigate the mechanism of CD36 in NAFLD.

Navigation-Guided Nasal Endoscopy to Remove the Cavernous Venous Malformation of the Orbital Apex Through the Sphenoid Approach.

OBJECTIVE: To explore the feasibility of navigation-guided sinus endoscopy to remove the cavernous vascular malformation of the orbital apex through the sphenoid approach. METHODS: A retrospective series of non-control cases were collected. From May 2012 to December 2019, patients with imaging findings of cavernous venous malformation in the orbital apex were collected at the Eye Hospital Affiliated to Nanchang University. All patients underwent navigation guided sinusoscopy through the sphenoid approach to remove the cavernous venous malformation of the orbital apex. Analyze the changes of visual function and postoperative complications before and after operation. RESULTS: Twelve patients were collected, including 3 males and 9 females aged between 32 and 59. In 3 patients without visual impairment, the postoperative visual function was still normal. The remaining 9 patients all had visual impairment. Among them, 3 patients had fully recovered normal visual function after operation, 2 patients had improved visual function compared with preoperative, and 4 patients had no change in postoperative visual acuity. There were no complications in 3 of the 12 patients, and 9 patients had transient limited intraocular rotation with mild limitation of diplopia after operation, and all returned to normal within 1 month after surgery. CONCLUSION: Navigation-guided sinus endoscopy through the sphenoid approach to remove the cavernous venous malformation of the orbital apex is an effective and feasible surgical method.

Antibacterial activities against Ralstonia solanacearum and Xanthomonas oryzae pv. oryzae of 6-chloro-4-(4-substituted piperazinyl)quinazoline derivatives.

In this letter, a variety of simple 6-chloro-4-(4-substituted piperazinyl)quinazoline derivatives was prepared. Preliminary bioassays revealed that these compounds showed good antibacterial activities toward phytopathogens Ralstonia solanacearum and Xanthomonas oryzae pv. oryzae (Xoo). Among these derivatives, compounds 5a, 5d, 5e, 5f, 5p, 5q, 6b, and 6d exhibited potent inhibition effects against R. solanacearum with EC50 within 4.60-9.94 µg/mL, especially, compound 5g exerted the strongest activity with EC50 of 2.72 µg/mL; compound 6b possessed the best inhibitory activity toward Xoo with EC50 of 8.46 µg/mL. Subsequently, a good predictive three-dimensional quantitative structure-activity relationship (3D-QSAR) model was constructed via CoMFA to direct the future structural modification and optimization. Furthermore, the pathogens' topological studies were performed to explore the possible antibacterial mechanism. Given their simple frameworks and facile synthesis, title compounds can serve as the potential antibacterial leads.

[Comparison of three medical goggle sterilizing approaches].

OBJECTIVE: To compare three sterilizing methods for reusable medical goggles. METHODS: A total of 180 medical goggles of the same brand and same model were randomly divided into three groups. In group A the goggles were first soaked with 2000 mg/L chlorine-containing disinfectant and then cleaned manually; goggles in other two groups were sterilized using pre-programmed automatic spray cleaning and disinfection machine, the disinfection program was set to 90 ℃ for 5 min in group B and 70 ℃ for 30 min in group C. The quality of the sterilization was monitored by visual inspection with luminous magnifying glass and residual protein detection assay. User satisfaction on cleanliness of medical goggles, clarity of mirror surface and suitability of elastic bands was investigated with questionnaire survey. RESULTS: The qualification rates verified by visual inspection were 82.4%, 84.6%and 98.3%in group A, B and C, respectively, the qualification rate in group C was significantly higher than those in group B and group C (all P<0.05). The qualification rates verified by residual protein detection assay were 96.7%, 100.0%and 100.0%in group A, B and C, respectively (P>0.05). A total of 54 questionnaires were submitted for the survey. The satisfaction rates were 100.0%, 90.7%and 94.4% for cleanliness of medical goggles, clarity of mirror surface and suitability of elastic bands, respectively. CONCLUSIONS: Machinery sterilization set 70 ℃ for 30 min has better cleaning and sterilizing effects for reusable medical goggles.

Identification and Application of an Aptamer Targeting Papillary Thyroid Carcinoma Using Tissue-SELEX.

Aptamers, short DNA or RNA oligonucleotides, which evolved from systematic evolution of ligands by exponential enrichment (SELEX), can perform specific target recognition. Papillary thyroid carcinoma (PTC) is of high incidence worldwide, and the prognosis of advanced PTC is poor. Up to now, there is no specific biomarker that can identify PTC and defects still remain in existing diagnostic methods. Here we report an aptamer, termed TC-6, which is generated from tissue-SELEX by using sections of papillary thyroid carcinoma and a normal thyroid gland. TC-6 could specifically target intracellular components of papillary thyroid cells with high affinity ( Kd = 57.66 ± 5.93 nmol/L) and have performed excellent biocompatibility both in vivo and in vitro. Moreover, fluorescence imaging of PTC tumor-bearing mice revealed that TC-6 was able to accumulate in tumor sites and could distinguish thyroid carcinoma from other benign thyroid diseases efficiently. In addition, TC-6d, a truncated aptamer of TC-6, maintained its affinity toward PTC with Kd of 39.20 ± 8.20 nmol/L. Overall, these results indicate that TC-6 is a potential candidate for developing novel tools for diagnosis and targeted therapy of PTC.

RNA Interference Silencing of Glycogen Synthase Kinase 3ß Inhibites Tau Phosphorylation in Mice with Alzheimer Disease.

To explore the effect of glycogen synthase kinase 3ß (GSK-3ß) silencing on Tau-5 phosphorylation in mice suffering Alzheimer disease (AD). GSK-3ß was firstly silenced in human neuroblastoma SH-SY5Y cells using special lentivirus (LV) and the content of Tau (A-12), p-Tau (Ser396) and p-Tau (PHF-6) proteins. GSK-3ß was also silenced in APP/PS1 mouse model of AD mice, which were divided into three groups (n = 10): AD, vehicle, and LV group. Ten C57 mice were used as control. The memory ability of mice was tested by square water maze, and the morphological changes of hippocampus and neuron death were analyzed by haematoxylin-eosin staining. Moreover, the levels of Tau and phosphorylated Tau (p-Tau) were detected by western blotting and immunohistochemistry, respectively. The lentivirus-mediated GSK-3ß silencing system was successfully developed and silencing GSK-3ß at the cellular level reduced Tau phosphorylation obviously. Moreover, GSK-3ß silence significantly improved the memory ability of AD mice in LV group compared with AD group (P < 0.05) according to the latency periods and error numbers. As for the hippocampus morphology and neuron death, no significant change was observed between LV group and normal control. Immunohistochemical detection and western blotting revealed that the levels of Tau and p-Tau were significantly down-regulated after GSK-3ß silence. Silencing GSK-3ß may have a positive effect on inhibiting the pathologic progression of AD through down-regulating the level of p-Tau.

Towards understanding the unusual photoluminescence intensity variation of ultrasmall colloidal PbS quantum dots with the formation of a thin CdS shell.

In this study, we report anomalous size-dependent photoluminescence (PL) intensity variation of PbS quantum dots (QDs) with the formation of a thin CdS shell via a microwave-assisted cation exchange approach. Thin shell formation has been established as an effective strategy for increasing the PL of QDs. Nonetheless, herein we observed an unusual PL decrease in ultrasmall QDs upon shell formation. We attempted to understand this abnormal phenomenon from the perspective of trap density variation and the probability of electrons and holes reaching surface defects. To this end, the quantum yield (QY) and PL lifetime (on the ns-µs time scales) of pristine PbS QDs and PbS/CdS core/shell QDs were measured and the radiative and non-radiative recombination rates were derived and compared. Moreover, transient absorption (TA) analysis (on the fs-ns time scale) was performed to better understand exciton dynamics at early times that lead to and affect longer time dynamics and optical properties such as PL. These experimental results, in conjunction with theoretical calculations of electron and hole wave functions, provide a complete picture of the photophysics governing the core/shell system. A model was proposed to explain the size-dependent optical and dynamic properties observed.

Organolead Halide Perovskite Nanocrystals: Branched Capping Ligands Control Crystal Size and Stability.

CH3 NH3 PbBr3 perovskite nanocrystals (PNCs) of different sizes (ca. 2.5-100 nm) with high photoluminescence (PL) quantum yield (QY; ca. 15-55 %) and product yield have been synthesized using the branched molecules, APTES and NH2 -POSS, as capping ligands. These ligands are sterically hindered, resulting in a uniform size of PNCs. The different capping effects resulting from branched versus straight-chain capping ligands were compared and a possible mechanism proposed to explain the dissolution-precipitation process, which affects the growth and aggregation of PNCs, and thereby their overall stability. Unlike conventional PNCs capped with straight-chain ligands, APTES-capped PNCs show high stability in protic solvents as a result of the strong steric hindrance and propensity for hydrolysis of APTES, which prevent such molecules from reaching and reacting with the core of PNCs.

Using DNA aptamer probe for immunostaining of cancer frozen tissues.

Tissue immunostaining is critically important in clinical applications, and antibodies have been used extensively as the molecular probes. Recently, aptamer, as a new class of probes, have attracted much attention for their potential clinical and research value. Epithelial cell adhesion molecule (EpCAM) is a specific biomarker which is overexpressed in many cancers of epithelial origin. Here, a DNA-based EpCAM aptamer SYL3C is reported as a probe for the immunostaining of frozen and paraffin-embedded sections of colorectal cancer tissues. Commercialized EpCAM antibodies were also used as a standard control. EpCAM aptamer SYL3C specifically recognized and immunostained cancer nests of colorectal tumor sections, but it neither reacted with background cells within tumor sites nor exhibited cross-reaction to the benign lesions or inflammation of colorectal tissues. No cross-linking to EpCAM-negative malignant tumor sections occurred. Compared with standard antibody staining, our EpCAM aptamer SYL3C protocol is simpler to implement with a shorter reaction time. Moreover, SYL3C can specifically bind with either frozen or paraffin-embedded tissue sections. Since the histopathology of frozen tissue is closer to that of fresh tissue and since frozen sections can be produced more quickly than paraffin-embedded sections, SYL3C immunostaining of frozen sections is a quick protocol that is easy to implement.

P2X7 receptors and Fyn kinase mediate ATP-induced oligodendrocyte progenitor cell migration.

Recruitment of oligodendrocyte precursor cells (OPCs) to the lesions is the most important event for remyelination after central nervous system (CNS) injury or in demyelinating diseases. However, the underlying molecular mechanism is not fully understood. In the present study, we found high concentrations of ATP could increase the number of migrating OPCs in vitro, while after pretreatment with oxidized ATP (a P2X7 receptor antagonist), the promotive effect was attenuated. The promotive effect of 2'(3')-O-(4-benzoylbenzoyl) adenosine 5'-triphosphate (BzATP) (a P2X7 receptor agonist) was more potent than ATP. After incubation with BzATP, the activity of Fyn, one member of the Src family of kinases, was enhanced. Moreover, the interaction between P2X7 and Fyn was identified by co-immunoprecipitation. After blocking the activity of Fyn or down-regulating the expression of Fyn, the migration of OPCs induced by BzATP was inhibited. These data indicate that P2X7 receptors/Fyn may mediate ATP-induced OPC migration under pathological conditions.

Vaspin as a Risk Factor of Insulin Resistance in Obstructive Sleep Apnea-Hypopnea Syndrome in an Animal Model.

BACKGROUND: In this study, we aimed to establish a chronic intermittent hypoxia model in rats and explore the possible role of vaspin in insulin sensitivity. METHODS: Healthy male Wistar rats were randomly divided into two groups: normal control group (NC) and chronic intermittent hypoxia group (CIH). The NC group was raised under physiological conditions and the CIH group was kept in the plexiglass chamber between 9 am and 5 pm undergoing intermittent hypoxic challenge for 8 hours/day for 8 weeks. Arterial blood pressure of rats (tail cannulation) was measured before and after the study. Fasting plasma glucose (FPG), total cholesterol (TC), triglycerides (TG), fasting insulin (FINS), vaspin, and leptin levels were measured. Vaspin mRNA expression in visceral adipose tissues was measured with Real Time-PCR. The protein levels of vaspin, Akt and phospho-Akt in visceral tissues were determined by Western-blot. RESULTS: At baseline, all the measurements in the CIH and NC groups were comparable. By the end of the experiment, the blood pressure of the CIH group was significantly higher than the NC group. The levels of FPG, FINS, TG, TC, leptin, and vaspin in the CIH group were significantly higher than in NC group. Plasma vaspin levels were correlated with FINS, HOMA-IR, and TG levels. Vaspin expression in both mRNA and protein levels in visceral adipose tissues of the CIH group were clearly higher than the NC group. Phospho-Akt protein level was decreased in visceral adipose tissues of the CIH group compared to the NC group. CONCLUSIONS: In the chronic intermittent hypoxia rat model, the expression of vaspin in visceral adipose tissues and plasma were increased, which were correlated with insulin resistance.

Au nanostructure-decorated TiO2 nanowires exhibiting photoactivity across entire UV-visible region for photoelectrochemical water splitting.

Here we demonstrate that the photoactivity of Au-decorated TiO2 electrodes for photoelectrochemical water oxidation can be effectively enhanced in the entire UV-visible region from 300 to 800 nm by manipulating the shape of the decorated Au nanostructures. The samples were prepared by carefully depositing Au nanoparticles (NPs), Au nanorods (NRs), and a mixture of Au NPs and NRs on the surface of TiO2 nanowire arrays. As compared with bare TiO2, Au NP-decorated TiO2 nanowire electrodes exhibited significantly enhanced photoactivity in both the UV and visible regions. For Au NR-decorated TiO2 electrodes, the photoactivity enhancement was, however, observed in the visible region only, with the largest photocurrent generation achieved at 710 nm. Significantly, TiO2 nanowires deposited with a mixture of Au NPs and NRs showed enhanced photoactivity in the entire UV-visible region. Monochromatic incident photon-to-electron conversion efficiency measurements indicated that excitation of surface plasmon resonance of Au is responsible for the enhanced photoactivity of Au nanostructure-decorated TiO2 nanowires. Photovoltage experiment showed that the enhanced photoactivity of Au NP-decorated TiO2 in the UV region was attributable to the effective surface passivation of Au NPs. Furthermore, 3D finite-difference time domain simulation was performed to investigate the electrical field amplification at the interface between Au nanostructures and TiO2 upon SPR excitation. The results suggested that the enhanced photoactivity of Au NP-decorated TiO2 in the UV region was partially due to the increased optical absorption of TiO2 associated with SPR electrical field amplification. The current study could provide a new paradigm for designing plasmonic metal/semiconductor composite systems to effectively harvest the entire UV-visible light for solar fuel production.

Surface coating combined with in situ cyclic voltammetry to enhance the stability of gas diffusion electrodes for electrochemical CO2 reduction.

Electrochemical CO2 reduction (CO2RR), fueled by clean and renewable energy, presents a promising method for utilizing CO2 effectively. The electrocatalytic reduction of CO2 to CO using a gas diffusion electrode (GDE) has shown great potential for industrial applications due to its high reaction rate and selectivity. However, guaranteeing its long-term stability still poses a significant challenge. In this study, we conducted a comprehensive investigation into various strategies to enhance the stability of the GDE. These strategies involved modifying the structure of the substrate, such as the gas diffusion layer (GDL) and the back side of the GDL (macroporous layer side). Additionally, we explored modifications to the catalyst layer (CL) and the front of the CL. To address these stability concerns, we proposed a practical approach that involved surface coating using carbon black in combination with in situ cyclic voltammetry (CV) cycles on Ag/Ag300/polytetrafluoroethylene (PTFE). The partial Faradaic efficiency exceeded 80 % within a span of 70 h. Electron microscopy and electrochemical characterization revealed that the implementation of in situ CV led to a reduction in catalyst particle size and the formation of a porous surface structure. By enhancing the stability of the GDE, this research opens up possibilities for the advancement of hybrid systems that focus on the production and utilization of syngas.

Effect of Lattice Disorder on Exciton Dynamics in Copper-Doped InP/ZnSexS1-x Core/Shell Quantum Dots.

InP/ZnSexS1-x core/shell quantum dots (QDs) with varying Cu concentrations were synthesized by a one-pot hot-injection method. X-ray diffraction and high-resolution transmission electron microscopy results indicate that Cu doping did not alter the crystal structure or particle size of the QDs. The optical shifts in UV-visible absorption and photoluminescence (PL) suggest changes in the electronic structure and induction of lattice disorder due to Cu doping. Ultrafast transient absorption spectroscopy (TAS) reveled that a higher Cu-doping level leads to faster charge carrier recombination, likely due to increased nonradiative decay from defect states. Time-resolved PL (TRPL) studies show longer average lifetimes of charge carriers with increased Cu doping. These findings informed the development of a kinetic model to better understand how Cu-induced disorder affects charge carrier dynamics in the QDs, which is important for emerging applications of Cu-doped InP/ZnSexS1-x QDs in optoelectronics.