A universal approach to dual-metal-atom catalytic sites confined in carbon dots for various target reactions.

Here, a molecular-design and carbon dot-confinement coupling strategy through the pyrolysis of bimetallic complex of diethylenetriamine pentaacetic acid under low-temperature is proposed as a universal approach to dual-metal-atom sites in carbon dots (DMASs-CDs). CDs as the "carbon islands" could block the migration of DMASs across "islands" to achieve dynamic stability. More than twenty DMASs-CDs with specific compositions of DMASs (pairwise combinations among Fe, Co, Ni, Mn, Zn, Cu, and Mo) have been synthesized successfully. Thereafter, high intrinsic activity is observed for the probe reaction of urea oxidation on NiMn-CDs. In situ and ex situ spectroscopic characterization and first-principle calculations unveil that the synergistic effect in NiMn-DMASs could stretch the urea molecule and weaken the N-H bond, endowing NiMn-CDs with a low energy barrier for urea dehydrogenation. Moreover, DMASs-CDs for various target electrochemical reactions, including but not limited to urea oxidation, are realized by optimizing the specific DMAS combination in CDs.

Asymmetrically Coordinated Calcium Single Atom for High-Performance Oxygen Reduction Reaction.

S-block single atoms represent an ideal catalyst for the oxygen reduction reaction (ORR) as they can suppress the Fenton reaction. However, the symmetry of the s/p orbitals tends to generate either an excessively strong or weak interaction with intermediates. Herein, Ca single atoms coordinated with -S, -OP, and three N atoms (Ca/NPS-HC) were fabricated to modulate the adsorption of intermediates and promote the efficiency of s-block ORR catalysts. The experimental results from ORR demonstrated that the Ca/NPS-HC catalyst exhibited outstanding catalytic capability with a half-wave potential of 0.89 V, a kinetic current density of 56.6 mA cm-2 at 0.85 V, and a Tafel slope of 42 mV dec-1, outperforming commercial Pt/C. The detailed mechanistic studies revealed that the asymmetric coordination of Ca single atoms led to the symmetry-breaking of electron distribution in Ca single atoms, attenuating the s-p hybridization from the intermediate adsorption process, and thereby minimizing the energy barrier of the whole ORR.

Targeting SUMOylation with an injectable nanocomposite hydrogel to optimize radiofrequency ablation therapy for hepatocellular carcinoma.

BACKGROUND: Incomplete radiofrequency ablation (iRFA) in hepatocellular carcinoma (HCC) often leads to local recurrence and distant metastasis of the residual tumor. This is closely linked to the development of a tumor immunosuppressive environment (TIME). In this study, underlying mechanisms and potential therapeutic targets involved in the formation of TIME in residual tumors following iRFA were explored. Then, TAK-981-loaded nanocomposite hydrogel was constructed, and its therapeutic effects on residual tumors were investigated. RESULTS: This study reveals that the upregulation of small ubiquitin-like modifier 2 (Sumo2) and activated SUMOylation is intricately tied to immunosuppression in residual tumors post-iRFA. Both knockdown of Sumo2 and inhibiting SUMOylation with TAK-981 activate IFN-1 signaling in HCC cells, thereby promoting dendritic cell maturation. Herein, we propose an injectable PDLLA-PEG-PDLLA (PLEL) nanocomposite hydrogel which incorporates self-assembled TAK-981 and BSA nanoparticles for complementary localized treatment of residual tumor after iRFA. The sustained release of TAK-981 from this hydrogel curbs the expansion of residual tumors and notably stimulates the dendritic cell and cytotoxic lymphocyte-mediated antitumor immune response in residual tumors while maintaining biosafety. Furthermore, the treatment with TAK-981 nanocomposite hydrogel resulted in a widespread elevation in PD-L1 levels. Combining TAK-981 nanocomposite hydrogel with PD-L1 blockade therapy synergistically eradicates residual tumors and suppresses distant tumors. CONCLUSIONS: These findings underscore the potential of the TAK-981-based strategy as an effective therapy to enhance RFA therapy for HCC.

Effects of probiotic supplementation on 12 min run performance, mood management, body composition and gut microbiota in amateur marathon runners: A double-blind controlled trial.

Background: Probiotic supplementation has a positive effect on endurance exercise performance and body composition in athletes, but the underlying mechanisms remain unclear. Gut microbiota can provide measurable markers of immune function in athletes, and microbial composition analysis may be sensitive enough to detect stress and metabolic disorders caused by exercise. Methods: Nineteen healthy active amateur marathon runners (15 male and 4 female) with a mean age of 29.11 years volunteered to participate in this double-blind controlled study. Based on the performance of the Cooper 12-min running test (CRT), the participants were allocated into two groups to receive either a probiotic formulation comprising lactobacillus acidophilus and bifidobacterium longum (n = 10) or placebo containing maltodextrin (n = 9) for five weeks. Consistency of diet and exercise was ensured throughout the experimental period. Before and after the intervention, all participants were assessed for CRT, emotional stability and gastrointestinal symptoms, gut microbiota composition, body composition and magnetic resonance imaging (MRI) indicators of skeletal muscle microcirculation. Results: Compared to before the intervention, the probiotics group showed an increase in CRT score (2.88 ± 0.57 vs 3.01 ± 0.60 km, P＜0.05), significant improvement in GSRS and GIQLI (9.20 ± 4.64 vs 7.40 ± 3.24, 118.90 ± 12.30 vs 127.50 ± 9.85, P＜0.05), while these indicators remained unchanged in the control group, with a significant time-group interaction effect on gastrointestinal symptoms. Additionally, some MRI metabolic cycling indicators of the thigh skeletal muscle also changed in the probiotics group (P＜0.05). Regarding microbiota abundance, the probiotics group exhibited a significant increase in the abundance of beneficial bacteria and a significant decrease in the abundance of harmful bacteria post-intervention (P＜0.05). Conclusion: As a sports nutritional supplement, probiotics have the potential to improve athletic performance by optimizing the balance of gut microbiota, alleviating gastrointestinal symptoms.

pH-Universal Electrocatalytic CO2 Reduction with Ampere-level Current Density on Doping-engineered Bismuth Sulfide.

The practical application of the electrocatalytic CO2 reduction reaction (CO2RR) to form formic acid fuel is hindered by the limited activation of CO2 molecules and the lack of universal feasibility across different pH levels. Herein, we report a doping-engineered bismuth sulfide pre-catalyst (BiS-1) that S is partially retained after electrochemical reconstruction into metallic Bi for CO2RR to formate/formic acid with ultrahigh performance across a wide pH range. The best BiS-1 maintains a Faraday efficiency (FE) of ~95% at 2000 mA cm-2 in a flow cell under neutral and alkaline solutions. Furthermore, the BiS-1 catalyst shows unprecedentedly high FE (~95%) with current densities from 100 to 1300 mA cm-2 under acidic solutions. Notably, the current density can reach 700 mA cm-2 while maintaining a FE of above 90% in a membrane electrode assembly electrolyzer and operate stably for 150 h at 200 mA cm-2. In-situspectra and density functional theory calculations reveals that the S doping modulates the electronic structure of Bi and effectively promotes the formation of the HCOO* intermediate for formate/formic acid generation. This work develops the efficient and stable electrocatalysts for sustainable formate/formic acid production.

Stretchable Oxygen-Tolerant Sensor Based on a Single-Atom Fe-N4 Electrocatalyst for Observing the Role of Oxidative Stress in Hypertension.

Oxidative stress and related oxidative damage have a causal relation with the pathogenesis of hypertension. Therefore, it is crucial to determine the mechanism of oxidative stress in hypertension by applying mechanical forces on cells to simulate hypertension while monitoring the release of reactive oxygen species (ROS) from cells under an oxidative stress environment. However, cellular level research has rarely been explored because monitoring the ROS released by cells is still challenging owing to the interference of O2. In this study, an Fe single-atom-site catalyst anchored on N-doped carbon-based materials (Fe SASC/N-C) was synthesized, which exhibits excellent electrocatalytic activity for the reduction of hydrogen peroxide (H2O2) at a peak potential of +0.1 V and can effectively avoid the interference of O2. Furthermore, we constructed a flexible and stretchable electrochemical sensor based on the Fe SASC/N-C catalyst to study the release of cellular H2O2 under simulated hypoxic and hypertension conditions. Density functional theory calculations show that the highest transition state energy barrier from the oxygen reduction reaction (ORR), i.e., O2 to H2O, is 0.38 eV. In comparison, the H2O2 reduction reaction (HPRR) can be completed only by overcoming a lower energy barrier of 0.24 eV, endowing the HPRR to be more favorable on Fe SASC/N-C compared with the ORR. This study provided a reliable electrochemical platform for real-time investigation of H2O2-related underlying mechanisms of the hypertension process.

Light Field-Enhanced Single-Site Cu Electrocatalyst for Nitrogen Fixation.

Direct electrocatalytic reduction of N2 to NH3 under mild conditions is attracting considerable interests but still remains enormous challenges in terms of respect of intrinsic catalytic activity and limited electrocatalytic efficiency. Herein, a photo-enhanced strategy is developed to improve the NRR activity on Cu single atoms catalysts. The atomically dispersed Cu single atoms supported TiO2 nanosheets (Cu SAs/TiO2 ) achieve a Faradaic Efficiency (12.88%) and NH3 yield rate (6.26 µg h-1 mgcat -1 ) at -0.05 V versus RHE under the light irradiation field, in which NH3 yield rate is fivefold higher than that under pure electrocatalytic nitrogen reduction reaction (NRR) process and is remarkably superior in comparison to most of the similar type electrocatalysts. The existence of external light field improves electron transfer ability between CuO and TiO, and thus optimizes the accumulation of surface charges on Cu sites, endowing more electrons involved in nitrogen fixation. This work reveals an atomic-scale mechanistic understanding of field effect-enhanced electrochemical performance of catalysts and it provides predictive guidelines for the rational design of photo-enhanced electrochemical N2 reduction catalysts.

D-Band Center Optimization of Edge-Rich Ultrathin RuZn Nanosheets With Moiré Superlattices for pH-Universal Hydrogen Evolution Reaction.

Electrocatalytic hydrogen evolution reaction (HER) is a promising way to produce pure and clean hydrogen. However, the preparation of efficient and economical catalysts for pH-universal HER remains a challenging but rewarding task. Herein, ultrathin RuZn nanosheets (NSs) with moiré superlattices and abundant edges are synthesized. The RuZn NSs with unique structure exhibit superb HER performance with overpotentials of 11, 13, and 29 mV to achieve 10 mA cm-2 in 1 M KOH, 1 M PBS, and 0.5 M H2 SO4 , respectively, which is substantially lower than those of Ru NSs and RuZn NSs without moiré superlattices. Density functional theory investigations reveal that the charge transfer from Zn to Ru will lead the appropriate downshift of the d-band center of surface Ru atoms, thus accelerating hydrogen desorption from the Ru sites, lowering the dissociation energy barrier of water and greatly improving the HER performance. This work provides an effective design scheme for high-performance HER electrocatalysts over a wide pH range, and propose a general route to prepare Ru-based bimetallic nanosheets with moiré superlattices.

Mitochondrial ROS driven by NOX4 upregulation promotes hepatocellular carcinoma cell survival after incomplete radiofrequency ablation by inducing of mitophagy via Nrf2/PINK1.

BACKGROUND: The recurrence of hepatocellular carcinoma (HCC) after radiofrequency ablation (RFA) remains a major clinical problem. Cells that survive the sublethal heat stress that is induced by incomplete RFA are the main source of HCC relapse. Heat stress has long been reported to increase intracellular reactive oxygen species (ROS) generation. Although ROS can induce apoptosis, a pro-survival effect of ROS has also been demonstrated. However, the role of ROS in HCC cells exposed to sublethal heat stress remains unclear. METHODS: HepG2 and HuH7 cells were used for this experiment. Insufficient RFA was performed in cells and in a xenograft model. ROS and antioxidant levels were measured. Apoptosis was analyed by Annexin-V/PI staining and flow cytometry. Protein expression was measured using western blotting. Colocalization of lysosomes and mitochondria was analyzed to assess mitophagy. Corresponding activators or inhibitors were applied to verify the function of specific objectives. RESULTS: Here,we showed that sublethal heat stress induced a ROS burst, which caused acute oxidative stress. This ROS burst was generated by mitochondria, and it was initiated by upregulated NOX4 expression in the mitochondria. N-acetylcysteine (NAC) decreased HCC cell survival under sublethal heat stress conditions in vivo and in vitro. NOX4 triggers the production of mitochondrial ROS (mtROS), and NOX4 inhibitors or siNOX4 also decreased HCC cell survival under sublethal heat stress conditions in vitro. Increased mtROS trigger PINK1-dependent mitophagy to eliminate the mitochondria that are damaged by sublethal heat stress and to protect cells from apoptosis. Nrf2 expression was elevated in response to this ROS burst and mediated the ROS burst-induced increase in PINK1 expression after sublethal heat stress. CONCLUSION: These data confirmed that the ROS burst that occurs after iRFA exerted a pro-survival effect. NOX4 increased the generation of ROS by mitochondria. This short-term ROS burst induced PINK1-dependent mitophagy to eliminate damaged mitochondria by increasing Nrf2 expression.

Identification of a CEACAM5 targeted nanobody for positron emission tomography imaging and near-infrared fluorescence imaging of colorectal cancer.

PURPOSE: Here, we aim to identify a CEACAM5-targeted nanobody and demonstrate its application in positron emission tomography (PET) imaging and near-infrared (NIR) fluorescence imaging in colorectal cancer (CRC). METHODS: Immunohistochemistry was applied to verify CEACAM5 expression in CRC and metastatic lymph nodes (mLNs). CEACAM5-targeted nanobodies were obtained by immunization of human CEACAM5 protein in a dromedary, followed by several rounds of phage screenings. Immunofluorescence staining and flow cytometry was carried out to determine the binding affinity of the nanobodies. The nanobodies were radiolabeled by coupling 18F-SFB for PET imaging of CRC subcutaneous xenografts and lymph node metastasis (LNM). IRDye800CW (IR800) were conjugated to form NIR probes for NIR imaging in CRC subcutaneous models. RESULTS: CEACAM5 was overexpressed in either human CRC tissues or mLNs. A CEACAM5 targeted nanobody, Nb41 was successfully generated, with excellent in vitro binding properties. Incorporation of albumin binding domain (ABD) did not affect the affinity of Nb41. In vivo imaging showed that both 18F-FB-Nb41 and 18F-FB-Nb41-ABD showed obvious accumulation in the tumor. Due to the longer retention in the blood, 18F-FB-Nb41-ABD enrichment in tumors was significantly delayed but higher compared to 18F-FB-Nb41. Both 18F-FB-Nb41 and 18F-FB-Nb41-ABD showed prominent LNM enrichment. Similarly, the IR800-conjugated nanobodies Nb41-IR800 and Nb41-ABD-IR800 exhibited superior imaging effects in subcutaneous models, while Nb41-ABD-IR800 exhibited higher fluorescence intensity in the tumor accompanied with a remarkedly delay compared to Nb41-IR800. CONCLUSION: Collectively, we presented the identification and in vivo validation of a CEACAM5-targeted nanobody and a fused nanobody with an ABD, which enabled to the non-invasive visualization of malignancy of CRC using PET imaging and NIR imaging in subcutaneous models as well as LNM models.

Population impact of fine particulate matter on tuberculosis risk in China: a causal inference.

BACKGROUND: Previous studies have suggested the potential association between air pollution and tuberculosis incidence, but this association remains inconclusive and evidence to assess causality is particularly lacking. We aimed to draw causal inference between fine particulate matter less than 2.5 µm in diameter (PM2.5) and tuberculosis in China. METHODS: Granger causality (GC) inference was performed within vector autoregressive models at levels and/or first-differences using annual national aggregated data during 1982-2019, annual provincial aggregated data during 1982-2019 and monthly provincial aggregated data during 2004-2018. Convergent cross-mapping (CCM) approach was used to determine the backbone nonlinear causal association based on the monthly provincial aggregated data during 2004-2018. Moreover, distributed lag nonlinear model (DLNM) was applied to quantify the causal effects. RESULTS: GC tests identified PM2.5 driving tuberculosis dynamics at national and provincial levels in Granger sense. Empirical dynamic modeling provided the CCM causal intensity of PM2.5 effect on tuberculosis at provincial level and demonstrated that PM2.5 had a positive effect on tuberculosis incidence. Then, DLNM estimation demonstrated that the PM2.5 exposure driven tuberculosis risk was concentration- and time-dependent in a nonlinear manner. This result still held in the multi-pollutant model. CONCLUSIONS: Causal inference showed that PM2.5 exposure driving tuberculosis, which showing a concentration gradient change. Air pollutant control may have potential public health benefit of decreasing tuberculosis burden.

Acute effects of foam rolling and dynamic stretching on angle-specific change of direction ability, flexibility and reactive strength in male basketball players.

The purpose of our study was to determine the acute effects of dynamic stretching (DS), foam rolling (FR) and foam rolling combined with dynamic stretching (Combo) protocols on angle-specific change of direction (COD) ability, drop jump (DJ) performance and flexibility. Using a counterbalance crossover study design, eleven male basketball collegiate players (20.7 ± 0.6 years) were randomly assigned to one of the four protocols - control (CON), DS, FR, Combo - for each session, for a total of four sessions. A more aggressive foam cylinder with raised nodules, which is thought to be effective in stimulating the deep layer of muscle tissue, was used to observe for changes in their performance during sit and reach (SAR), DJ and COD tasks in 45 and 180 degrees. One-way repeated measures ANOVA was used to identify differences of each variable separately between interventions. The SAR after three interventions compared to the CON was significantly improved (F (3,30) = 5.903, P = 0.003, η2 = 0.371). In the 505 test, both limbs failed to show a significant improvement in COD deficit. The non-dominant limb showed a significant improvement of 6.4% after FR when performing the Y-shaped agility (F (3,30) = 4.962, P = 0.0065 < 0.05, η2 = 0.332). In the DJ, the reactive strength index and contact time changed significantly by 17.5% and -17.5% (η2 = 0.518, η2 = 0.571), respectively, immediately after FR. The current research suggested that FR may have an enhancing effect on COD speed in a 45° cutting task and neuromuscular function, while having the potential to improve non-dominant limb deficits in both COD tasks. In contrast, the Combo warm-up protocol did not produce a cumulative effect, suggesting the need for coaches to remain cautious about excessive warm-up duration.

Engineering a Copper Single-Atom Electron Bridge to Achieve Efficient Photocatalytic CO2 Conversion.

Developing highly efficient and stable photocatalysts for the CO2 reduction reaction (CO2 RR) remains a great challenge. We designed a Z-Scheme photocatalyst with N-Cu1 -S single-atom electron bridge (denoted as Cu-SAEB), which was used to mediate the CO2 RR. The production of CO and O2 over Cu-SAEB is as high as 236.0 and 120.1 µmol g-1 h-1 in the absence of sacrificial agents, respectively, outperforming most previously reported photocatalysts. Notably, the as-designed Cu-SAEB is highly stable throughout 30 reaction cycles, totaling 300 h, owing to the strengthened contact interface of Cu-SAEB, and mediated by the N-Cu1 -S atomic structure. Experimental and theoretical calculations indicated that the SAEB greatly promoted the Z-scheme interfacial charge-transport process, thus leading to great enhancement of the photocatalytic CO2 RR of Cu-SAEB. This work represents a promising platform for the development of highly efficient and stable photocatalysts that have potential in CO2 conversion applications.

Highly Stable and Selective Sensing of Hydrogen Sulfide in Living Mouse Brain with NiN4 Single-Atom Catalyst-Based Galvanic Redox Potentiometry.

Hydrogen sulfide (H2S) is recognized as a gasotransmitter and multifunctional signaling molecule in the central nervous system. Despite its essential neurofunctions, the chemical dynamics of H2S during physiological and pathological processes remains poorly understood, emphasizing the significance of H2S sensor development. However, the broadly utilized electrochemical H2S sensors suffer from low stability and sensitivity loss in vivo due to sulfur poisoning-caused electrode passivation. Herein, we report a high-performance H2S sensor that combines single-atom catalyst strategy and galvanic redox potentiometry to overcome the issue. Atomically dispersed NiN4 active sites on the sensing interface promote electrochemical H2S oxidation at an extremely low potential to drive spontaneous bipolarization of a single carbon fiber. Bias-free potentiometric sensing at open-circuit condition minimizes sulfur accumulation on the electrode surface, thus significantly enhancing the stability and sensitivity. The resulting sensor displays high selectivity to H2S against physiological interferents and enables real-time accurate quantification of H2S-releasing behavior in the living mouse brain.

Hsa-microRNA-370-3p targeting Snail and Twist1 suppresses IL-8/STAT3-driven hepatocellular carcinoma metastasis.

The pro-inflammatory factor interleukin-8 (IL-8) is related to poor prognosis in hepatocellular carcinoma (HCC) patients. Interleukin-8 enhanced HCC invasion by upregulating Snail and Twist1, whether this modulation relies on microRNAs (miR) is unclear. In this study, hsa-miR-370-3p was screened as candidate miRNA targeting Snail and Twist1, and its expression was downregulated by IL-8. Luciferase assays and RNA electrophoretic mobility shift assays were used to evaluate the interaction between miR-370-3p and targeted mRNAs. Coimmunoprecipitation, luciferase, and ChIP assays were undertaken to investigate the mechanisms underlying IL-8-mediated modification of miR-370-3p. Gain- and loss-of-function studies, Transwell assays, and a xenograft nude mouse model were used to investigate pro- and antitumor activities. Interleukin-8 and miR-370-3p levels were analyzed for clinical relevance in HCC patients. Our results showed that HCC patients with high levels of IL-8 experienced more metastasis and shorter survival. Interleukin-8 induced epithelial-mesenchymal transition and promoted liver cancer cell migration, invasion, and metastasis both in vitro and in vivo. MicroRNA-370-3p interacted with its cognate mRNA within the 3'-UTR regions of Twist1 and Snail mRNA directly and specifically and attenuated IL-8 protumoral effects on liver cancer cells. Interleukin-8 negatively modulated miR-370-3p through signal transducer and activator of transcription 3 (STAT3) activation by recruiting histone deacetylase 1 (HDAC1) to miR-370-3p promoter. The STAT3 and HDAC antagonists inhibited liver cancer cell migration and invasion. Patients with high miR-370-3p and low IL-8 levels had longer overall survival. In conclusion, our study elucidated a novel axis IL-8/STAT3/miR-370-3p/Twist1 and Snail relying on HDAC1 recruitment, which showed both diagnostic and therapeutic potentials of miR-370-3p in HCC metastasis.

Hemodialysis Arteriovenous Fistula Dysfunction: Retrospective Comparison of Post-thrombotic Percutaneous Endovascular Interventions with Pre-emptive Angioplasty.

BACKGROUND: We aimed to compare the clinical outcomes of pre-emptive angioplasty versus post-thrombotic percutaneous endovascular restoration of dysfunctional arteriovenous fistula (AVF). METHODS: This retrospective study reviewed the data from 80 patients who underwent 114 endovascular interventions for a malfunctioning AVF from July 2016 to August 2019. Stenotic AVFs were treated with pre-emptive angioplasty. Thrombosed AVFs were treated with percutaneous pharmacomechanical fibrinolysis with urokinase used only during the operation or continuously infused. The differences in patency rates were evaluated using the Kaplan-Meier method. In addition, univariate and multivariate regression Cox models were used to determine influential factors on the postintervention primary patency. RESULTS: Post-thrombotic interventions and pre-emptive angioplasty yielded statistically similar rates in clinical success (100 vs. 100%), anatomic success (94 vs. 89%; P = 0.52), complication (4 vs. 11%; P = 0.29), as well as postintervention primary, assisted primary and secondary patency (P = 0.80; 0.57; 0.57). The use of pre-emptive angioplasty was associated with reduced total cost (¥25,108 vs. ¥30,833, P < 0.001). The patients who used urokinase only during the operation prolonged both the primary and assisted primary patency (P = 0.02; 0.002), while those with continuous infusion of urokinase had worst patency rates and high costs (¥39,275 vs. ¥25,108 vs. ¥27,140, P < 0.001). Compared with the other locations, dysfunction in the anastomotic or juxta-anastomotic segment (HR = 0.41, P = 0.001) was associated with prolonged postintervention primary patency. CONCLUSIONS: No clinical outcome differences were found between the post-thrombotic percutaneous endovascular interventions and pre-emptive angioplasty. However, pre-emptive angioplasty decreased access expenditure.

P and Cu Dual Sites on Graphitic Carbon Nitride for Photocatalytic CO2 Reduction to Hydrocarbon Fuels with High C2 H6 Evolution.

The light-driven CO2 reduction to multi-carbon products is especially meaningful, while the low efficiency of multi-electron transfer and sluggish C-C coupling greatly hinder its development. Herein, we report a photocatalyst comprising of P and Cu dual sites anchored on graphitic carbon nitride (P/Cu SAs@CN), which achieves a high C2 H6 evolution rate of 616.6 µmol g-1 h-1 in reducing CO2 to hydrocarbons. The detailed spectroscopic characterizations identify the formation of charge-enriched Cu sites, where the isolated P atoms serve as hole capture sites during photocatalysis. Theoretical simulations combined with in situ FTIR measurement reveal a kinetically feasible process for the formation of C-C coupling intermediate (*OC-COH) and confirm the favorable production of C2 H6 on the P/Cu SAs@CN photocatalyst. This work offers new insights into the photocatalyst design with atomic precision toward highly efficient photocatalytic CO2 conversion to high value-added carbon products.

Highly Efficient Electrosynthesis of Nitric Oxide for Biomedical Applications.

Nitric oxide (NO) constitutes one of the most versatile therapeutics for biomedical applications. The efficient and on-demand NO generation essentially dictates its concentration dependent therapeutic activity. Here, we report an electrochemical system employing a rationally designed single-iron atom based biomimetic catalyst (i.e., Fe SAC), for high-efficient and controlled NO generation. The Fe SAC shows superior catalytic ability in electrochemical reduction of nitrite, with maximal NO generation rate achieving 2.1 µM (min µg)-1 . Theoretical studies suggest the significant decrease of Gibbs-free energy of NO2 - adsorption on single-iron atom accounts for its high catalytic efficiency. Moreover, ample amount of NO can be controllably generated in a potential dependent manner. For antibacterial application, the generated NO overwhelmingly disrupts both gram-negative and gram-positive strains, highlighting a great promise to expedite NO research in both basic and applied sciences.

Design of Binary Cu-Fe Sites Coordinated with Nitrogen Dispersed in the Porous Carbon for Synergistic CO2 Electroreduction.

To relieve the green gas emission and involve the carbon neutral cycle, electrochemical reduction of CO2 attracts more and more attention. Herein, a biatomic site catalyst of Cu-Fe coordinated with the nitrogen, which is doped in the carbon matrix (denoted as Cu-Fe-N6 -C), is designed. The as-obtained Cu-Fe-N6 -C exhibits higher performance than that of Cu-N-C and Fe-N-C, owing to bimetallic sites, proving synergistic functions based on different molecules and their interfaces. Cu-Fe-N6 -C shows high selectivity toward CO, with high Faradaic efficiency (98% at -0.7 V), and maintaining 98% of its initial selectivity after 10 h electrolysis. The experimental results and theoretical calculations reveal that the synergistic catalysis of different metallic sites enlarges the adsorption enthalpy of CO2 , reducing the activation energy result in generating high selectivity, activity, stability, and low impedance.

Isolated Ni Atoms Dispersed on Ru Nanosheets: High-Performance Electrocatalysts toward Hydrogen Oxidation Reaction.

Designing low-cost, high-efficiency, platinum-free electrocatalysts for the hydrogen oxidation reaction (HOR) in an alkaline electrolyte is of great importance for the development of anion exchange membrane fuel cells. Herein, we report a novel HOR catalyst, RuNi1, in which Ni is atomically dispersed on the Ru nanocrystals. To note, the as-prepared RuNi1 catalyst exhibits excellent catalytic activity and stability for HOR in alkaline media, which is superior to those of Ru-Ni bimetallic nanocrystals, pristine Ru, and commercial Pt/C catalysts. Density functional theory (DFT) calculations suggest that isolation of Ni atoms on Ru nanocrystals not only optimizes the hydrogen-binding energy but also decreases the free energy of water formation, thus leading to excellent electrocatalytic activity of RuNi1 catalyst. The results show that engineering a catalyst at an atomic level is highly effective for rational design of electrocatalysts with high performance.