LARP3, LARP7, and MePCE are involved in the early stage of human telomerase RNA biogenesis.

Human telomerase assembly is a highly dynamic process. Using biochemical approaches, we find that LARP3 and LARP7/MePCE are involved in the early stage of human telomerase RNA (hTR) and that their binding to RNA is destabilized when the mature form is produced. LARP3 plays a negative role in preventing the processing of the 3'-extended long (exL) form and the binding of LARP7 and MePCE. Interestingly, the tertiary structure of the exL form prevents LARP3 binding and facilitates hTR biogenesis. Furthermore, low levels of LARP3 promote hTR maturation, increase telomerase activity, and elongate telomeres. LARP7 and MePCE depletion inhibits the conversion of the 3'-extended short (exS) form into mature hTR and the cytoplasmic accumulation of hTR, resulting in telomere shortening. Taken together our data suggest that LARP3 and LARP7/MePCE mediate the processing of hTR precursors and regulate the production of functional telomerase.

Tuning Crystal Phase of Palladium-Selenium Nanowires for Enhanced Ethylene Glycol Electrocatalytic Oxidation.

Alcohol electrooxidation is pivotal for a sustainable energy economy. However, designing efficient electrocatalysts for this process is still a formidable challenge. Herein, palladium-selenium nanowires featuring distinct crystal phases: monoclinic Pd7Se2 and tetragonal Pd4.5Se for ethylene glycol electrooxidation reaction (EGOR) are synthesized. Notably, the supported monoclinic Pd7Se2 nanowires (m-Pd7Se2 NWs/C) exhibit superior EGOR activity, achieving a mass activity (MA) and specific activity (SA) of 10.4 A mgPd -1 (18.7 mA cm-2), which are 8.0 (6.7) and 10.4 (8.2) times versus the tetragonal Pd4.5Se and commercial Pd/C and surpass those reported in the literature. Furthermore, m-Pd7Se2 NWs/C displays robust catalytic activity for other alcohol electrooxidation. Comprehensive characterization and density functional theory (DFT) calculations reveal that the enhanced electrocatalytic performance is attributed to the increased formation of Pd0 on the high-index facets of the m-Pd7Se2 NWs, which lowers the energy barriers for the C─C bond dissociation in CHOHCHOH* and the CO* oxidation to CO2*. This study provides palladium-based alloy electrocatalysts exhibiting the highest mass activity reported to date for the electrooxidation of ethylene glycol, achieved through the crystalline phase engineering strategy.

CT findings as predictive factors for treatment failure in Mycobacterium abscessus complex lung disease: a retrospective cohort study.

PURPOSE: Mycobacterium abscessus complex (MABC) commonly causes lung disease (LD) and has a high treatment failure rate of around 50%. In this study, our objective is to investigate specific CT patterns for predicting treatment prognosis and monitoring treatment response, thus providing valuable insights for clinical physicians in the management of MABC-LD treatment. METHODS: We retrospectively assessed 34 patients with MABC-LD treated between January 2015 and December 2020. CT scores for bronchiectasis, cellular bronchiolitis, consolidation, cavities, and nodules were measured at initiation and after treatment. The ability of the CT scores to predict treatment outcomes was analyzed in logistic regression analyses. RESULTS: The CT scoring system had excellent inter-reader agreement (all intraclass correlation coefficients, > 0.82). The treatment failure (TF) group (17/34; 50%) had higher cavitation diameter (p = 0.049) and extension (p = 0.041) at initial CT and higher cavitation diameter (p = 0.049) and extension (p =0 .045), consolidation (p = 0.022), and total (p = 0.013) scores at follow-up CT than the treatment success (TS) group. The changes of total score and consolidation score (p = 0.049 and 0.024, respectively) increased in the TF group more than the TS group between the initial and follow-up CT. Multivariable logistic regression analysis showed initial cavitation extension, follow-up consolidation extension, and change in consolidation extension (adjusted odds ratio: 2.512, 2.495, and 9.094, respectively, per 1-point increase; all p < 0.05) were significant predictors of treatment failure. CONCLUSIONS: A high pre-treatment cavitation extension score and an increase in the consolidation extension score during treatment on CT could be alarm signs of treatment failure requiring tailor the treatment of MABC-LD carefully.

Diagnostic performance of computed tomography-digital subtraction angiography and conventional magnetic resonance imaging for evaluating the vascularity of osseous spinal tumors.

BACKGROUND AND PURPOSE: Patients with hypervascular spinal tumors may have severe blood loss during tumor resection, which increases the risks of perioperative morbidity and mortality. However, the preoperative evaluation of tumor vascularity may be challenging; moreover, the reliability of the data obtained in conventional preoperative noninvasive imaging is debatable. In this study, we compared conventional magnetic resonance imaging (MRI) and subtraction computed tomography angiography (CTA) in terms of their performance in vascularity evaluation. The catheter digital subtraction angiography (DSA) technique was used as a reference standard. METHODS: This study included 123 consecutive patients with spinal tumor who underwent subtraction CTA, catheter DSA, and subsequent surgery between October 2015 and October 2021. Data regarding qualitative and semiquantitative subtraction CTA parameters and conventional MRI signs were collected for comparison with tumor vascularity graded through catheter DSA. The diagnostic performance of qualitative CTA, quantitative CTA, and conventional MRI in assessing spinal tumor vascularity was analyzed. RESULTS: Qualitative subtraction CTA was the best noninvasive imaging modality in terms of diagnostic performance (area under the receiver operating characteristic curve [AUROC], 0.95). Quantitative CTA was relatively inferior (AUROC, 0.87). MRI results had low reliability (AUROC, 0.51 to 0.59). Intratumoral hemorrhage and prominent foraminal venous plexus were found to be the specific signs for hypervascularity (specificity 93.2%). CONCLUSIONS: Qualitative subtraction CTA offers the highest diagnostic value in evaluating spinal tumor vascularity, compared to quantitative CTA and MRI. Although conventional MRI may not be a reliable approach, certain MRI signs may have high specificity, which may be crucial for assessing spinal tumor vascularity.

Efficacy of Electroacupuncture Combined with Chinese Herbal Medicine on Pain Intensity for Chronic Sciatica Secondary to Lumbar Disc Herniation: Study Protocol for a Randomised Controlled Trial.

Purpose: Chinese herbal medicine and electroacupuncture (EA) have been used to control pain for many decades in China. We aim to explore the efficacy of intervening patients whose discogenic sciatica symptoms lasting longer than 3 months with these conservative treatments. Patients and Methods: This is a single-center, parallel-group, patient-unblinded Randomized Controlled Trial (RCT) with blinded outcome assessment and statistician. One hundred and twenty-four patients will be assigned randomly into 2 groups including conservative treatment group (Shenxie Zhitong capsule combined with EA treatment) and Nonsteroidal Anti-inflammatory Drugs (Nonsteroidal Anti-inflammatory Drugs, NSAIDs) control group (Celecoxib) in a 1:1 ratio. The trial involves a 4-week treatment along with follow-up for 6 months. The primary outcome is the leg pain intensity measured by the visual analogue scale (VAS) at 6 months after randomization. Secondary outcomes include leg pain intensity at other time points, back pain intensity, leg pain and back pain frequency, functional status, quality of life, return to work status and satisfaction of patients. Adverse events will also be recorded. Strengths and Limitations of This Study: Through this study, we want to observe the efficacy of electroacupuncture combined with Chinese herbal medicine on pain intensity for chronic sciatica secondary to Lumbar Disc Herniation. If the final results are favorable, it is expected to be a safe, economical, and effective treatment for patients. The study design has the following limitations: the setup of control group was less than perfect; patients and doctors could not be blinded in this trial; we skipped the feasibility study. We have tried our best to minimize adverse impacts. Trial Registration: ChiCTR2300070884 (Chinese Clinical Trial Registry, http://www.chictr.org.cn, registered on 25th April 2023).

A Sustainable Route to Ruthenium Phosphide (RuP)/Ru Heterostructures with Electron-Shuttling of Interfacial Ru for Efficient Hydrogen Evolution.

Ruthenium (Ru) is a promising electrocatalyst for the hydrogen evolution reaction (HER), despite suffering from low activity in non-acidic conditions due to the high kinetic energy barrier of H2O dissociation. Herein, the synthesis of carbon nanosheet-supported RuP/Ru heterostructures (RuP/Ru@CNS) from a natural polysaccharide is reported and demonstrates its behavior as an effective HER electrocatalyst in non-acidic conditions. The RuP/Ru@CNS exhibits low overpotential (106 mV at 200 mA·cm-2) in alkaline electrolyte, exceeding most reported Ru-based electrocatalysts. The electron shuttling between Ru atoms at the RuP/Ru interface results in a lowered energy barrier for H2O dissociation by electron-deficient Ru atoms in the pure Ru phase, as well as optimized H* adsorption of electron-gaining Ru atoms in the neighboring RuP. A low H* spillover energy barrier between Ru atoms at the RuP/Ru interface further boosts HER kinetics. This study demonstrates a sustainable method for the fabrication of efficient Ru-based electrocatalysts and provides a more detailed understanding of interface effects in HER catalysis.

Mortality and disability risk among older adults unable to complete grip strength and physical performance tests: a population-based cohort study from China.

BACKGROUND: The link between low grip strength, diminished physical performance, and adverse health outcomes in older adults has been well-established. However, the impact of older adults who cannot complete these tests on disability and mortality rates remains unexplored without longitudinal study. METHODS: We collected data from the China Health and Retirement Longitudinal Study (CHARLS). Participants aged 60-101 were enrolled at baseline. We analyzed the prevalence of populations unable to complete handgrip strength (HGS), gait speed (GS), and five times chair stand test (FTCST). Completing risk models were used to estimate the risk of mortality and disability over seven years. RESULTS: A total of 3,768 participants were included in the analysis. The percentage of older adults unable to complete the GS and FTCST tests increased notably with age, from 2.68 to 8.90% and 2.60-20.42%, respectively. The proportion of older people unable to perform the HGS was relatively stable, ranging from 1.40 to 3.66%. Compared to older adults who can complete these tests, those who cannot perform FTCST face a significantly higher risk of mortality, with 49.1% higher risk [hazard ratio (HR) = 1.491, 95% CI = 1.156, 1.922; subdistribution hazard ratio (SHR) = 1.491, 95%CI = 1.135,1.958)]. Participants who were unable to complete the GS test had a higher risk of developing ADL disability, regardless of whether they were compared to the lowest-performing group (HR = 1.411, 95%CI = 1.037,1.920; SHR = 1.356, 95%CI = 1.030,1.785) or those who can complete the GS (HR = 1.727, 95%CI = 1.302,2.292; SHR = 1.541, 95%CI = 1.196,1.986). No statistically significant difference in the risk of developing ADL disability among older adults who were unable to complete the HGS test compared with either the poorest performing group (HR = 0.982, 95% CI = 0.578, 1.666; SHR = 1.025, 95% CI = 0.639, 1.642) or those who were able to complete the HGS test (HR = 1.008, 95% CI = 0.601, 1.688; SHR = 0.981, 95% CI = 0.619, 1.553). The risk of all-cause mortality was not significantly different for older adults who were unable to complete the HGS test compared to those with the worst performance (HR = 1.196, 95%CI = 0.709-2.020; SHR = 1.196, 95%CI = 0.674, 2.124) or those who were able to complete the test (HR = 1.462, 95%CI = 0.872-2.450; SHR = 1.462, 95%CI = 0.821,2.605). CONCLUSION: The risks of adverse events faced by older adults unable to complete the tests vary, indicating the necessity for future research to conduct separate analyses on this high-risk population.

Implanting oxophilic metal in PtRu nanowires for hydrogen oxidation catalysis.

Bimetallic PtRu are promising electrocatalysts for hydrogen oxidation reaction in anion exchange membrane fuel cell, where the activity and stability are still unsatisfying. Here, PtRu nanowires were implanted with a series of oxophilic metal atoms (named as i-M-PR), significantly enhancing alkaline hydrogen oxidation reaction (HOR) activity and stability. With the dual doping of In and Zn atoms, the i-ZnIn-PR/C shows mass activity of 10.2 A mgPt+Ru-1 at 50 mV, largely surpassing that of commercial Pt/C (0.27 A mgPt-1) and PtRu/C (1.24 A mgPt+Ru-1). More importantly, the peak power density and specific power density are as high as 1.84 W cm-2 and 18.4 W mgPt+Ru-1 with a low loading (0.1 mg cm-2) anion exchange membrane fuel cell. Advanced experimental characterizations and theoretical calculations collectively suggest that dual doping with In and Zn atoms optimizes the binding strengths of intermediates and promotes CO oxidation, enhancing the HOR performances. This work deepens the understanding of developing novel alloy catalysts, which will attract immediate interest in materials, chemistry, energy and beyond.

Vacancy-induced catalytic mechanism for alcohol electrooxidation on nickel-based electrocatalyst.

Owing to outstanding performances, nickel-based electrocatalysts are commonly used in electrochemical alcohol oxidation reactions (AORs), and the active phase is usually vacancy-rich nickel oxide/hydroxide (NiOx Hy ) species. However, researchers are not aware of the catalytic role of atom vacancy in AORs. Here, we study vacancy-induced catalytic mechanisms for AORs on NiOx Hy species. As to AORs on oxygen-vacancy-poor ß-Ni(OH)2 , the only redox mediator is electrooxidation-induced electrophilic lattice oxygen species, which can only catalyze the dehydrogenation process (e.g., the electrooxidation of primary alcohol to carboxylic acid) instead of the C-C bond cleavage. Hence, vicinal diol electrooxidation reaction involving the C-C bond cleavage is not feasible with oxygen-vacancy-poor ß-Ni(OH)2 . Only through oxygen vacancy-induced adsorbed oxygen-mediated mechanism, can oxygen-vacancy-rich NiOx Hy species catalyze the electrooxidation of vicinal diol to carboxylic acid and formic acid accompanied with the C-C bond cleavage. Crucially, we examine how vacancies and vacancy-induced catalytic mechanisms work during AORs on NiOx Hy species.

Reducing the Ir-O Coordination Number in Anodic Catalysts based on IrOx Nanoparticles towards Enhanced Proton-exchange-membrane Water Electrolysis.

Due to the robust oxidation conditions in strong acid oxygen evolution reaction (OER), developing an OER electrocatalyst with high efficiency remains challenging in polymer electrolyte membrane (PEM) water electrolyzer. Recent theoretical research suggested that reducing the coordination number of Ir-O is feasible to reduce the energy barrier of the rate-determination step, potentially accelerating the OER. Inspired by this, we experimentally verified the Ir-O coordination number's role at model catalysts, then synthesized low-coordinated IrOx nanoparticles toward a durable PEM water electrolyzer. We first conducted model studies on commercial rutile-IrO2 using plasma-based defect engineering. The combined in situ X-ray absorption spectroscopy (XAS) analysis and computational studies clarify why the decreased coordination numbers increase catalytic activity. Next, under the model studies' guidelines, we explored a low-coordinated Ir-based catalyst with a lower overpotential of 231 mV@10 mA cm-2 accompanied by long durability (100 h) in an acidic OER. Finally, the assembled PEM water electrolyzer delivers a low voltage (1.72 V@1 A cm-2 ) as well as excellent stability exceeding 1200 h (@1 A cm-2 ) without obvious decay. This work provides a unique insight into the role of coordination numbers, paving the way for designing Ir-based catalysts for PEM water electrolyzers.

Association between elevated serum uric acid levels and high estimated glomerular filtration rate with reduced risk of low muscle strength in older people: a retrospective cohort study.

BACKGROUND: We aimed to investigate the interaction between serum uric acid (SUA) levels with estimated glomerular filtration rate (eGFR) to low muscle strength (LMS) among older people in China. METHODS: Cohort data were obtained from China Health and Retirement Longitudinal Study (CHARLS) in 2011 and 2015. A total of 2,822 community-dwelling adults aged 60 and above were enrolled for the follow-up. Serum uric acid was collected after 8 h of fasting, and handgrip strength was measured with a dynamometer. eGFR was calculated with an equation based on the Chinese population. A generalized additive model was employed for interaction analysis and progressively adjusted confounders. RESULTS: During the follow-up, a total of 659 individuals were excluded due to the lack of grip strength data, leaving 2,163 participants for analysis. Despite the protective effect of high uric acid against low muscle strength, especially in older females, it is not statistically significant (OR = 0.69, 95%CI = 0.45-1.04, P = 0.075). Following the progressive adjustment of covariates, the association between higher eGFR and elevated SUA levels remained statistically significant in females, showing a reduced odds ratio with low muscle strength (OR = 0.82, 95%CI = 0.70-0.97, P = 0.021). However, this trend was not observed in male participants. CONCLUSIONS: This Chinese population-based cohort study suggests that among older females, a higher serum uric acid level combined with a higher estimated glomerular filtration rate is linked to a reduced risk of low muscle strength. This implies that the relationship between high serum uric acid levels and the risk of low grip strength might differ by gender.

Temperature-Dependent Structures of Single-Atom Catalysts.

Single-atom catalysts (SACs) have the unique coordination environment and electronic structure due to the quantum size effect, which plays an essential role in facilitating catalytic reactions. However, due to the limited understanding of the formation mechanism of single atoms, achieving the modulation of the local atomic structure of SACs is still difficult and challenging. Herein, we have prepared a series of Ni SACs loaded on nitrogen-doped carbon substrates with different parameters using a dissolution-and-carbonization method to systematically investigate the effect of temperature on the structure of the SACs. The results of characterization and electrochemical measurements are analyzed to reveal the uniform law between temperature and the metal loading, bond length, coordination number, valence state and CO2 reduction performance, showing the feasibility of controlling the structure of SACs through temperature to regulate the catalytic performance. This is important for the understanding of catalytic reaction mechanisms and the design of efficient catalysts.

Structurally-Distorted RuIr-Based Nanoframes for Long-Duration Oxygen Evolution Catalysis.

Oxygen evolution reaction (OER) plays a key role in proton exchange membrane water electrolysis (PEMWE), yet the electrocatalysts still suffer from the disadvantages of low activity and poor stability in acidic conditions. Here, a new class of CdRu2 IrOx nanoframes with distorted structure for acidic OER is successfully fabricated. Impressively, CdRu2 IrOx displays an ultralow overpotential of 189 mV and an ultralong stability of 1500 h at 10 mA cm⁻2 toward OER in 0.5 M H2 SO4 . Moreover, a PEMWE using the distorted CdRu2 IrOx can be steadily operated at 0.1 A cm⁻2 for 90 h. Microstructural analyses and X-ray absorption spectroscopy (XAS) demonstrate that the synergy between Ru and Ir in CdRu2 IrOx induces the distortion of Ru-O, Ir-O, and Ru-M (M = Ru, Ir) bonds. In situ XAS indicates that the applied potential leads to the deformation octahedral structure of RuOx /IrOx and the formation of stable Ru5+ species for OER. Theoretical calculations also reveal that the distorted structures can reduce the energy barrier of rate-limiting step during OER. This work provides an efficient strategy for constructing structural distortion to achieve significant enhancement on the activity and stability of OER catalysts.

Defect-Rich SnO2 Nanofiber as an Oxygen-Defect-Driven Photoenergy Shield against UV Light Cell Damage.

Usually, most studies focus on toxic gas and photosensors by using electrospinning and metal oxide polycrystalline SnO2 nanofibers (PNFs), while fewer studies discuss cell-material interactions and photoelectric effect. In this work, the controllable surface morphology and oxygen defect (VO) structure properties were provided to show the opportunity of metal oxide PNFs to convert photoenergy into bio-energy for bio-material applications. Using the photobiomodulation effect of defect-rich polycrystalline SnO2 nanofibers (PNFs) is the main idea to modulate the cell-material interactions, such as adhesion, growth direction, and reactive oxygen species (ROS) density. The VO structures, including out-of-plane oxygen defects (op-VO), bridge oxygen defects (b-VO), and in-plane oxygen defects (ip-VO), were studied using synchrotron analysis to investigate the electron transfer between the VO structures and conduction bands. These intragrain VO structures can be treated as generation-recombination centers, which can convert various photoenergies (365-520 nm) into different current levels that form distinct surface potential levels; this is referred to as the photoelectric effect. PNF conductivity was enhanced 53.6-fold by enlarging the grain size (410 nm2) by increasing the annealing temperature, which can improve the photoelectric effect. In vitro removal of reactive oxygen species (ROS) can be achieved by using the photoelectric effect of PNFs. Also, the viability and shape of human bone marrow mesenchymal stem cells (hMSCs-BM) were also influenced significantly by the photobiomodulation effect. The cell damage and survival rate can be prevented and enhanced by using PNFs; metal oxide nanofibers are no longer only environmental sensors but can also be a bio-material to convert the photoenergy into bio-energy for biomedical science applications.

Identifying a Universal Activity Descriptor and a Unifying Mechanism Concept on Perovskite Oxides for Green Hydrogen Production.

Producing indispensable hydrogen and oxygen for social development via water electrolysis shows more prospects than other technologies. Although electrocatalysts have been explored for centuries, a universal activity descriptor for both hydrogen-evolution reaction (HER) and oxygen-evolution reaction (OER) is not yet developed. Moreover, a unifying concept is not yet established to simultaneously understand HER/OER mechanisms. Here, the relationships between HER/OER activities in three common electrolytes and over ten representative material properties on 12 3d-metal-based model oxides are rationally bridged through statistical methodologies. The orbital charge-transfer energy (Δ) can serve as an ideal universal descriptor, where a neither too large nor too small Δ (≈1 eV) with optimal electron-cloud density around Fermi level affords the best activities, fulfilling Sabatier's principle. Systematic experiments and computations unravel that pristine oxide with Δ ≈ 1 eV possesses metal-like high-valence configurations and active lattice-oxygen sites to help adsorb key protons in HER and induce lattice-oxygen participation in the OER, respectively. After reactions, partially generated metals in the HER and high-valence hydroxides in the OER dominate proton adsorption and couple with pristine lattice-oxygen activation, respectively. These can be successfully rationalized by the unifying orbital charge-transfer theory. This work provides the foundation of rational material design and mechanism understanding for many potential applications.

Unraveling the electrophilic oxygen-mediated mechanism for alcohol electrooxidation on NiO.

Aqueous organic electrosynthesis such as nucleophile oxidation reaction (NOR) is an economical and green approach. However, its development has been hindered by the inadequate understanding of the synergy between the electrochemical and non-electrochemical steps. In this study, we unravel the NOR mechanism for the primary alcohol/vicinal diol electrooxidation on NiO. Thereinto, the electrochemical step is the generation of Ni3+-(OH)ads, and the spontaneous reaction between Ni3+-(OH)ads and nucleophiles is an electrocatalyst-induced non-electrochemical step. We identify that two electrophilic oxygen-mediated mechanisms (EOMs), EOM involving hydrogen atom transfer (HAT) and EOM involving C-C bond cleavage, play pivotal roles in the electrooxidation of primary alcohol to carboxylic acid and the electrooxidation of vicinal diol to carboxylic acid and formic acid, respectively. Based on these findings, we establish a unified NOR mechanism for alcohol electrooxidation and deepen the understanding of the synergy between the electrochemical and non-electrochemical steps during NOR, which can guide the sustainable electrochemical synthesis of organic chemicals.

Tuning Electronic State and Charge Transport in B←N-Containing 2D Polymer Heterostructures with Efficient Photocatalytic Performance.

Linear-conjugated polymers (LCPs) are excellent semiconductor photocatalysts. However, its inherent amorphous structures and simple electron transport channels restrict efficient photoexcited charge separation and transfer. Herein, "2D conjugated engineering" is employed to design high-crystalline polymer photocatalysts with multichannel charge transport by introducing alkoxyphenyl sidechains. The electronic state structure and electron transport pathways of the LCPs are investigated using experimental and theoretical calculations. Consequently, the 2D B←N-containing polymers (2DPBN) exhibit excellent photoelectric characteristics, which enable the efficient separation of electron-hole and rapidly transfer photogenerated carriers to the catalyst surface for efficient catalytic reactions. Significantly, the further hydrogen evolution of 2DPBN-4F heterostructures can be achieved by increasing the fluorine content of the backbones. This study highlights that the rational design of LCP photocatalysts is an effective strategy to spur further interest in photofunctional polymer material applications.

Correlating the Valence State with the Adsorption Behavior of a Cu-Based Electrocatalyst for Furfural Oxidation with Anodic Hydrogen Production Reaction.

The low-potential furfural oxidation reaction (FFOR) on a Cu-based electrocatalyst can produce H2 at the anode, thereby providing a bipolar H2 production system with an ultralow cell voltage. However, the intrinsic activity and stability of the Cu-based electrocatalyst for the FFOR remain unsatisfactory for practical applications. This study investigates the correlation between the valence state and the adsorption behavior of the Cu-based electrocatalyst in furfural oxidation. Cu0 is the adsorption site with low intrinsic activity. Cu+ , which exists in the form of Cu(OH)ads in alkaline electrolytes, has no adsorption ability but can improve the performance of Cu0 by promoting the adsorption of FF. Moreover, a mixed-valence Cu-based electrocatalyst (MV Cu) with high intrinsic activity and stability is prepared electrochemically. With the MV Cu catalyst, the assembled dual-side H2 production electrolyzer has a low electricity requirement of only 0.24 kWh mH2 -3 at an ultralow cell voltage of 0.3 V, and it exhibits sufficient stability. This study not only correlates the valence state with the adsorption behavior of the Cu-based electrocatalyst for the low-potential FFOR with anodic H2 production but also reveals the mechanism of deactivation to provide design principles for Cu-based electrocatalysts with satisfactory stability.

Nitrogen substitution induced lattice contraction in nickel nanoparticles for electrochemical hydrogen evolution from simulated seawater.

Herein, we demonstrate a facile method for the introduction of nitrogen in the lattices of nickel nanoparticles to form NiNx (x = 0.13, 0.20, 0.27). X-ray absorption spectroscopy reveals the contraction of the Ni-Ni bond and modulated coordination environment after nitrogen introduction. The NiN0.20 required 87 mV overpotential for -10 mA cm-2 cathodic current density in simulated seawater. The density functional theory calculations revealed favorable EH2Oads and ΔGHads after N-introduction.

Low-coordinated Co-N3 sites induce peroxymonosulfate activation for norfloxacin degradation via high-valent cobalt-oxo species and electron transfer.

The identification of reactive species in peroxymonosulfate (PMS) activation triggered by carbon-based single atom catalysts is the key to reveal the pollutant degradation mechanism. Herein, carbon-based single atom catalyst with low-coordinated Co-N3 sites (CoSA-N3-C) was synthesized to active PMS for norfloxacin (NOR) degradation. The CoSA-N3-C/PMS system exhibited consistent high performance for oxidizing NOR over a wide pH range (3.0-11.0). The system also achieved complete NOR degradation in different water matrixes, high cycle stability and excellent degradation performance for other pollutants. Theoretical calculations confirmed that the catalytic activity was derived from the favorable electron density of low-coordinated Co-N3 configuration, which was more conductive to PMS activation than other configurations. Electron paramagnetic resonance spectra, in-situ Raman analysis, solvent exchange (H2O to D2O), salt bridge and quenching experiments concluded that high-valent cobalt(IV)-oxo species (56.75%) and electron transfer (41.22%) contributed dominantly to NOR degradation. Moreover, 1O2 was generated in the activation process while not involved in pollutant degradation. This research demonstrates the specific contributions of nonradicals in PMS activation over Co-N3 sites for pollutant degradation. It also offers updated perceptions for rational design of carbon-based single atom catalysts with appropriate coordination structure.