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Osteoarthritis (OA) is a prevalent degenerative disease characterized by irreversible destruction of articular cartilage, for which no current drugs are known to modify its progression. While intra-articular (IA) injections of hyaluronic acid (HA) offer temporary relief, their effectiveness and long-term benefits are debated. Alpha-ketoglutarate (αKG) has potential chondroprotective properties, but its use is limited by a short half-life and poor cartilage-targeting efficiency. Here, we developed self-assembled HA-αKG nanoparticles (NPs) to combine the benefits of both HA and αKG, showing stability, bioavailability, and sustained pH-responsive release in the knee joint. In both early and advanced OA stages in mice, HA, αKG, and HA-αKG NPs could relieve pain, enhance mobility, and reduce cartilage damage, with HA-αKG NPs demonstrating the best efficacy. Mechanistically, αKG not only promotes cartilage matrix synthesis but also inhibits degradation by activating the PERK-ATF4 signaling pathway to reduce endoplasmic reticulum stress (ERS) in chondrocytes. This study highlights the therapeutic potential of HA-αKG NPs for treating various OA stages, with efficient and sustained effects, suggesting rapid clinical adoption and high acceptability among clinicians and patients.
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Due to the insufficient Cu+ accumulation, Cu+ efflux mechanism, and highly immunosuppressive tumor microenvironment (TME) in lung metastasis, the cuproptosis efficacy is limited. Herein, an inhalable nanodevice (CLDCu) is constructed to successfully overcome the drawbacks of cuproptosis. CLDCu consists of a Cu2+-chitosan shell and low molecular weight heparin-tocopherol succinate (LMWH-TOS, LT) core with disulfiram (DSF) loading. The prepared CLDCu can be inhaled and accumulate in large amounts in lung lesions (63.6%) with 56.5 times higher than intravenous injection. Within tumor cells, the mild acidity triggers the co-release of DSF and Cu2+, thus generating bis(diethyldithiocarbamate)-copper (CuET) to block Cu+ efflux protein ATP7B and forming toxic Cu+, leading to enhanced cuproptosis. Meanwhile, the released chitosan cooperates with CLDCu-induced cuproptosis to activate stimulator of interferon genes (STING) pathway, which significantly potentiates dendritic cells (DCs) maturation, as wells as evokes innate and adaptive immunity. In lung metastatic mice model, CLDCu is found to induce cuproptosis and reverse the immunosuppressive TME by inhalation administration. Moreover, CLDCu combined with anti-programmed cell death protein ligand-1 antibody (aPD-L1) provokes stronger antitumor immunity. Therefore, nanomedicine that combines cuproptosis with STING activation is a novel strategy for tumor immunotherapy.
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The discovery of novel targeted agents for non-small cell lung cancer (NSCLC) remains an important research landscape due to the limited efficacy, side effects and drug resistance of current treatment options. Among many repurposed drugs, disulphiram (DSF) has shown the potential to target tumours. However, its unpleasant neurotoxicity greatly limits its use. A DSF derivative, S-(N,N-diethyldithiocarbamoyl)-N-acetyl-l-cysteine (DS-NAC), was synthesised against NSCLC. The therapeutic effects, mechanism and toxicities of DS-NAC were evaluated in A549 and H460 cells and the mouse model of in situ lung cancer. The in vitro results exhibited that DS-NAC had potent anti-proliferation, apoptotic, anti-metastasis and epithelial-mesenchymal transition (EMT) inhibition effects. In the orthotopic lung cancer mouse model, therapeutic effects of DS-NAC were better than those of DSF and were similar to docetaxel (DTX). Also, results from western blot and immunohistochemistry showed that DS-NAC in combination with copper exerted therapeutic effects via regulating NF-κB signalling pathway and ROS-related proteins such as HIF-1α, Nrf2 and PKC-δ rather than regulating ROS level directly. Moreover, the safety evaluation study showed that DS-NAC had low haematologic and hepatic toxicities in comparison with DTX as well as low neurological toxicity compared with DSF. DS-NAC could be a promising anti-lung cancer agent with a favourable safety profile.
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Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Transducción de Señal , Animales , Humanos , Ratones , Células A549 , Acetilcisteína/farmacología , Antineoplásicos/farmacología , Antineoplásicos/administración & dosificación , Apoptosis/efectos de los fármacos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ditiocarba/farmacología , Transición Epitelial-Mesenquimal/efectos de los fármacos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Ratones Endogámicos BALB C , Ratones Desnudos , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
N-acetylcysteine (NAC) is a commonly used mucolytic agent and antidote for acetaminophen overdose. For pulmonary diseases, NAC exhibits antioxidative properties, regulates cytokine production, reduces apoptosis of lung epithelial cells, and facilitates the resolution of inflammation. However, the efficacy of NAC in clinical trials targeting different pathological conditions is constrained by its short half-life and low bioavailability. In the present study, a series of NAC derivatives were designed and synthesized to further enhance its pharmacological activity. Structure-activity relationship (SAR) studies were conducted to optimize the activating groups. In vitro evaluations revealed that compounds 4 r, 4 t, 4 w, and 4 x exhibited superior antioxidative and anti-inflammatory activities compared to the positive controls of NAC and fudosteine. The ADME prediction analysis indicated that these compounds exhibited a favorable pharmacological profile. In-vivo experiments with compound 4 r demonstrated that the high-dose group (80â mg/kg) exhibited improved therapeutic effects in reversing the HPY level in mice with pulmonary fibrosis compared to the NAC group (500â mg/kg), further proving its superior oral bioavailability and therapeutic effect compared to NAC.
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Acetilcisteína , Antioxidantes , Diseño de Fármacos , Acetilcisteína/farmacología , Acetilcisteína/química , Acetilcisteína/síntesis química , Animales , Relación Estructura-Actividad , Antioxidantes/farmacología , Antioxidantes/síntesis química , Antioxidantes/química , Ratones , Estructura Molecular , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Relación Dosis-Respuesta a Droga , Fibrosis Pulmonar/tratamiento farmacológico , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/patología , Masculino , Humanos , Antiinflamatorios/farmacología , Antiinflamatorios/síntesis química , Antiinflamatorios/químicaRESUMEN
Addressing peripheral nerve defects remains a significant challenge in regenerative neurobiology. Autografts emerged as the gold-standard management, however, are hindered by limited availability and potential neuroma formation. Numerous recent studies report the potential of wireless electronic system for nerve defects repair. Unfortunately, few has met clinical needs for inadequate electrode precision, poor nerve entrapment and insufficient bioactivity of the matrix material. Herein, we present an advanced wireless electrical nerve stimulator, based on water-responsive self-curling silk membrane with excellent bioabsorbable and biocompatible properties. We constructed a unique bilayer structure with an oriented pre-stretched inner layer and a general silk membrane as outer layer. After wetting, the simultaneous contraction of inner layer and expansion of outer layer achieved controllable super-contraction from 2D flat surface to 3D structural reconfiguration. It enables shape-adaptive wrapping to cover around nerves, overcomes the technical obstacle of preparing electrodes on the inner wall of the conduit, and prevents electrode breakage caused by material expansion in water. The use of fork capacitor-like metal interface increases the contact points between the metal and the regenerating nerve, solving the challenge of inefficient and rough electrical stimulation methods in the past. Newly developed electronic stimulator is effective in restoring 10 mm rat sciatic nerve defects comparable to autologous grafts. The underlying mechanism involves that electric stimulation enhances anterograde mitochondrial transport to match energy demands. This newly introduced device thereby demonstrated the potential as a viable and efficacious alternative to autografts for enhancing peripheral nerve repair and functional recovery.
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Piezoelectric nanogenerators (PENGs) are booming for energy collection and wearable energy supply as one of the next generations of green energy-harvesting devices. Balancing the output, safety, degradation, and cost is the key to solving the bottleneck of PENG application. In this regard, yttrium (Y)-doped zinc oxide (ZnO) (Y-ZnO) was synthesized and embedded into polylactide (PLLA) for developing degradable piezoelectric composite films with an enhanced energy-harvesting performance. The synthesized Y-ZnO exhibits high piezoelectric properties benefiting from the stronger polarity of the Y-O bond and regulation of oxygen vacancy concentration, which improve the output performance of the composite film with Y-ZnO and PLLA (Y-Z-PLLA). The obtained open-circuit voltage (Voc), short-circuit current (Isc), and instantaneous power density of the optimized Y-Z-PLLA PENG reach 17.52 V, 2.45 µA, and 1.76 µW/cm2, respectively. The proposed PENG also shows good degradability. In addition, practical applications of the proposed PENG were demonstrated by converting biomechanical energy, such as walking, running, and jumping, into electricity.
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Bismuth-based materials have emerged as promising catalysts in the electrocatalytic reduction of CO2 to formate. However, the reasons for the reconstruction of Bi-based precursors to form bismuth nanosheets are still puzzling, especially the formation of defective bismuth sites. Herein, we prepare bismuth nanosheets with vacancy-rich defects (V-Bi NS) by rapidly reconstructing Bi19Cl3S27 under negative potential. Theoretical analysis reveals that the introduction of chlorine induces the generation of intrinsic electric field in the precursor, thereby increasing the electron transfer rate and further promoting the metallization of trivalent bismuth. Meanwhile, experimental tests verify that Bi19Cl3S27 has a faster reconstruction rate than Bi2S3. The formed V-Bi NS exhibits up to 96 % HCOO- Faraday efficiency and 400â mA cm-2 HCOO- partial current densities, and its electrochemical active surface area normalized formate current density and yield are 2.2â times higher than those of intact bismuth nanosheets (I-Bi NS). Density functional theory calculations indicate that bismuth vacancies with electron-rich aggregation reduce the activation energy of CO2 to *CO2 - radicals and stabilize the adsorption of the key intermediate *OCHO, thus facilitating the reaction kinetics of formate production.
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The carbon-carbon coupling at the Cu/Cu2O Schottky interface has been widely recognized as a promising approach for electrocatalytic CO2 conversion into value-added alcohols. However, the limited selectivity of C2+ alcohols persists due to the insufficient control over rectifying interface characteristics required for precise bonding of oxyhydrocarbons. Herein, we present an investigation into the manipulation of the coordination environment of Cu sites through an in-situ electrochemical reconstruction strategy, which indicates that the construction of low-coordinated Cu sites at the Cu/Cu2O interface facilitates the enhanced rectifying interfaces, and induces asymmetric electronic perturbation and faster electron exchange, thereby boosting C-C coupling and bonding oxyhydrocarbons towards the nucleophilic reaction process of *H2CCO-CO. Impressively, the low-coordinated Cu sites at the Cu/Cu2O interface exhibit superior faradic efficiency of 64.15 ± 1.92% and energy efficiency of ~39.32% for C2+ alcohols production, while maintaining stability for over 50 h (faradic efficiency >50%, total current density = 200 mA cm-2) in a flow-cell electrolyzer. Theoretical calculations, operando synchrotron radiation Fourier transform infrared spectroscopy, and Raman experiments decipher that the low-coordinated Cu sites at the Cu/Cu2O interface can enhance the coverage of *CO and adsorption of *CH2CO and CH2CHO, facilitating the formation of C2+ alcohols.
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Previous research has predominantly relied on single-informant reports to establish the association between parental control and children's anxiety. However, there remains ambiguity regarding the extent to which discrepancies in parent-child reports of parental control are related to children anxiety. This study examined parent-child perceived discrepancies in parental control and their association with children's anxiety, along with the moderated effect of parent-child closeness through cross-sectional and prospective analysis. The sample consisted of 790 children (Mage = 11.34, SD = 6.73, 45.60% for girls), with 741 father-child dyads and 760 mother-child dyads included. Data were analyzed using polynomial regressions with response surface analysis. The results indicated that children tended to perceive higher levels of parental psychological control and lower levels of behavioral control compared to their parents' perceptions. In the cross-sectional analysis, a significant association between greater incongruence in psychological/behavioral control and higher levels of children's anxiety at T1 was observed exclusively in father-child dyads. In prospective analysis, for both father-child and mother-child dyads, congruence in higher levels of psychological control was associated with higher levels of children's anxiety at T2, while congruence in higher levels of behavioral control was associated with lower levels of children's anxiety at T2. Additionally, greater incongruence in psychological/behavioral control was linked to higher levels of children's anxiety at T2. Furthermore, mother-child closeness emerged as a significant moderator such that perceived incongruence in psychological/behavioral control could not affect children's anxiety at T2 in the high mother-child closeness condition. These findings highlight the significance of considering parent-child congruence and incongruence when examining the impact of parental control on children's anxiety.
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Cuproptosis shows enormous application prospects in lung metastasis treatment. However, the glycolysis, Cu+ efflux mechanisms, and insufficient lung drug accumulation severely restrict cuproptosis efficacy. Herein, an inhalable poly (2-(N-oxide-N,N-diethylamino)ethyl methacrylate) (OPDEA)-coated copper-based metal-organic framework encapsulating pyruvate dehydrogenase kinase 1 siRNA (siPDK) is constructed for mediating cuproptosis and subsequently promoting lung metastasis immunotherapy, namely OMP. After inhalation, OMP shows highly efficient lung accumulation and long-term retention, ascribing to the OPDEA-mediated pulmonary mucosa penetration. Within tumor cells, OMP is degraded to release Cu2+ under acidic condition, which will be reduced to toxic Cu+ to induce cuproptosis under glutathione (GSH) regulation. Meanwhile, siPDK released from OMP inhibits intracellular glycolysis and adenosine-5'-triphosphate (ATP) production, then blocking the Cu+ efflux protein ATP7B, thereby rendering tumor cells more sensitive to OMP-mediated cuproptosis. Moreover, OMP-mediated cuproptosis triggers immunogenic cell death (ICD) to promote dendritic cells (DCs) maturation and CD8+ T cells infiltration. Notably, OMP-induced cuproptosis up-regulates membrane-associated programmed cell death-ligand 1 (PD-L1) expression and induces soluble PD-L1 secretion, and thus synergizes with anti-PD-L1 antibodies (aPD-L1) to reprogram immunosuppressive tumor microenvironment, finally yielding improved immunotherapy efficacy. Overall, OMP may serve as an efficient inhalable nanoplatform and afford preferable efficacy against lung metastasis through inducing cuproptosis and combining with aPD-L1.
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Hydrazine oxidation-assisted water splitting is a critical technology to tackle the high energy consumption in large-scale H2 production. Ru-based electrocatalysts hold promise for synergetic hydrogen reduction (HER) and hydrazine oxidation (HzOR) catalysis but are hindered by excessive superficial adsorption of reactant intermediate. Herein, this work designs Ru cluster anchoring on NiFe-LDH (denoted as Ruc/NiFe-LDH), which effectively enhances the intermediate adsorption capacity of Ru by constructing RuâOâNi/Fe bridges. Notably, it achieves an industrial current density of 1 A cm-2 at an unprecedentedly low voltage of 0.43 V, saving 3.94 kWh m-3 H2 in energy, and exhibits remarkable stability over 120 h at a high current density of 5 A cm-2. Advanced characterizations and theoretical calculation reveal that the presence of RuâOâNi/Fe bridges widens the d-band width (Wd) of the Ru cluster, leading to a lower d-band center and higher electron occupation on antibonding orbitals, thereby facilitating moderate adsorption energy and enhanced catalytic activity of Ru.
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Objectives: Gastric cancer (GC) is the leading digestive malignancy with high incidence and mortality rate. microRNAs (miRs) play an important role in GC progresssion. This study aimed to investigate the effect of miR-98-5p on proliferation, migration, and invasion of GC cells. Methods: The expression levels of miR-98-5p, ubiquitin specific peptidase 44 (USP44), and CCCTCbinding factor-like (CTCFL) in GC tissues and cells were identified using reversetranscription quantitative polymerase chain reaction and Western blot assay. The relationship between miR-98-5p expression/USP44 and the clinicopathological features in GC patients was analyzed. GC cell proliferation, invasion, and migration were evaluated by cell counting kit-8 and clone formation assays and Transwell assays. The bindings of miR-98-5p to USP44 and USP44 to CTCFL were examined using dualluciferase assay and co-immunoprecipitation. GC cells were treated with MG132 and the ubiquitination level of CTCFL was examined using ubiquitination assay. Rescue experiments were performed to verify the roles of USP44 and CTCFL in GC cells. Results: miR-98-5p was downregulated in GC. miR-98-5p overexpression inhibited the proliferation, migration, and invasion of GC cells. miR-98-5p inhibited USP44 expression. USP44 bound to CTCFL and limited ubiquitination degradation of CTCFL. Overexpression of USP44 and CTCFL attenuated the inhibitory effects of miR-98-5p overexpression on GC cell progression. Conclusion: miR-98-5p overexpression limited USP44-mediated CTCFL deubiquitination, and suppressed CTCFL expression, mitigating GC cell proliferation, migration, and invasion.
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As one of the most promising approaches to producing high-purity hydrogen (H2 ), electrochemical water splitting powered by the renewable energy sources such as solar, wind, and hydroelectric power has attracted considerable interest over the past decade. However, the water electrolysis process is seriously hampered by the sluggish electrode reaction kinetics, especially the four-electron oxygen evolution reaction at the anode side, which induces a high reaction overpotential. Currently, the emerging hybrid electrochemical water splitting strategy is proposed by integrating thermodynamically favorable electro-oxidation reactions with hydrogen evolution reaction at the cathode, providing a new opportunity for energy-efficient H2 production. To achieve highly efficient and cost-effective hybrid water splitting toward large-scale practical H2 production, much work has been continuously done to exploit the alternative anodic oxidation reactions and cutting-edge electrocatalysts. This review will focus on recent developments on electrochemical H2 production coupled with alternative oxidation reactions, including the choice of anodic substrates, the investigation on electrocatalytic materials, and the deep understanding of the underlying reaction mechanisms. Finally, some insights into the scientific challenges now standing in the way of future advancement of the hybrid water electrolysis technique are shared, in the hope of inspiring further innovative efforts in this rapidly growing field.
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OBJECTIVES: Diabetes mellitus (DM) is correlated with poor clinical outcomes in spinal surgery. However, the effect of it on screw stabilization has not been investigated. The aim of this study was to evaluate the screw loosening rate and postoperative outcomes in diabetic patients and to identify potential risk factors associated with loosening. METHODS: This was a retrospective study. Two hundred and forty-three patients who received cervical or lumbar internal fixation between 2015 and 2019 were enrolled. Screw loosening was assessed on radiography, and clinical outcomes were evaluated by the improvement of visual analogue scale (VAS), Oswestry disability index (ODI) or Japanese Orthopaedic Association (JOA) scores. The relationship of DM, screw loosening and clinical outcomes were analyzed with chi-square tests and regression analyses. RESULTS: One hundred and twenty-two patients (50.2%) with diabetes were included in this study. Diabetes led to the increase of the rate of screw loosening in the lumbar spine, while the loosening rate did not vary significantly in the cervical spine. The occurrence of screw loosening in the lumbar spine was more likely to be associated with clinical outcomes for motor performance including walking and sitting. However, no significant effect on JOA and VAS scores in the cervical spine of screw loosening was found. Moreover, the history of DM affected the outcomes of the patients who underwent spinal surgery. CONCLUSION: DM had an adverse effect on screw stabilization. The impaired improvement of clinical outcomes in diabetics after spinal surgery was related to screw loosening. In addition to the direct effects on operative wounds and neural function, the impact on the screws due to DM was also worth noting.
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Diabetes Mellitus , Tornillos Pediculares , Fusión Vertebral , Humanos , Estudios Retrospectivos , Fusión Vertebral/efectos adversos , Tornillos Óseos/efectos adversos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Resultado del TratamientoRESUMEN
When the initial size of an atom cloud in a cold atom interferometer is negligible compared to its size after free expansion, the interferometer is approximated to a point-source interferometer and is sensitive to rotational movements by introducing an additional phase shear in the interference sequence. This sensitivity on rotation enables a vertical atom-fountain interferometer to measure angular velocity in addition to gravitational acceleration, which it is conventionally used to measure. The accuracy and precision of the angular velocity measurement depends on proper extraction of frequency and phase from spatial interference patterns detected via the imaging of the atom cloud, which is usually affected by various systematic biases and noise. To improve the measurement, a pre-fitting process based on principal component analysis is applied to the recorded raw images. The contrast of interference patterns are enhanced by 7-12 dB when the processing is present, which leads to an enhancement in the precision of angular velocity measurements from 6.3 µrad/s to 3.3 µrad/s. This technique is applicable in various instruments that involve precise extraction of frequency and phase from a spatial interference pattern.
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Aceleración , Movimiento , Rotación , Diagnóstico por ImagenRESUMEN
Photocatalytic CO2 reduction (PCR) expresses great attraction to convert useless greenhouse gas into valuable chemical feedstock. However, the weak interactions between catalytic sites and PCR intermediates constrains the PCR activity and selectivity. Herein, we proposed a new strategy to match the intermediates due to the maximum orbital overlap of catalytic sites and C1 intermediates by establishing dual Jahn-Teller (J-T) sites, in which, the strongly asymmetric J-T sites can break the nonpolar CO2 molecules and self-adapt the different structure of C1 intermediates. Taking cobalt carbonate hydroxide as an example, the weakly symmetric dual cobalt (Co2 ) dual J-T sites, weakly asymmetric Fe&Co sites and strongly asymmetric Cu&Co sites were assembled. After illumination, the interaction between dual J-T sites and the CO2 molecules enhances J-T distortion, which further modulates the PCR activity and selectivity. As a result, the Cu&Co sites exhibited CO yield of 8137.9â µmol g-1 , about 2.3-fold and 4.2-fold higher than that of the Fe&Co and Co2 sites within 5-hour photoreaction, respectively. In addition, the selectivity achieved as high as 92.62 % than Fe&Co (88.67 %) and Co2 sites (55.33 %). This work provides a novel design concept for the construction of dual J-T sites to regulate the catalytic activity and selectivity.
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Hydrazine oxidation-assisted water electrolysis provides a promising way for the energy-efficient electrochemical hydrogen (H2) and synchronous decomposition of hydrazine-rich wastewater, but the development of highly active catalysts still remains a great challenge. Here, we demonstrate the robust and highly active Ru nanoparticles supported on the hollow N-doped carbon microtube (denoted as Ru NPs/H-NCMT) composite structure as HER and HzOR bifunctional electrocatalysts. Thanks to such unique hierarchical architectures, the as-synthesized Ru NPs/H-NCMTs exhibit prominent electrocatalytic activity in the alkaline condition, which needs a low overpotential of 29 mV at 10 mA cm-2 for HER and an ultrasmall working potential of -0.06 V (vs RHE) to attain the same current density for HzOR. In addition, assembling a two-electrode hybrid electrolyzer using as-prepared Ru NPs/H-NCMT catalysts shows a small cell voltage of mere 0.108 V at 100 mA cm-2, as well as the remarkable long-term stability. Density functional theory calculations further reveal that the Ru NPs serve as the active sites for both the HER and HzOR in the nanocomposite, which facilitates the adsorption of H atoms and hydrazine dehydrogenation kinetics, thus enhancing the performances of HER and HzOR. This work paves a novel avenue to develop efficient and stable electrocatalysts toward HER and HzOR that promises energy-saving hybrid water electrolysis electrochemical H2 production.
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Glycerol-assisted hybrid water electrolysis is a potential strategy to achieve energy-efficient hydrogen production. However, the design of an efficient catalyst for the specific reaction is still a key challenge, which suffers from the barrier of regulating the adsorption characteristics of distinctive intermediates in different reactions. Herein, a novel rationale that achieves selective adsorption behavior modulation for self-supported nickel selenide electrode by heteroatom implantation and heterointerface construction through electrodeposition is developed, which can realize nichetargeting optimization on hydrogen evolution reaction (HER) and glycerol oxidation reaction (GOR), respectively. Specifically, the prepared Mo-doped Ni3 Se2 electrode exhibits superior catalytic activity for HER, while the NiSe-Ni3 Se2 electrode exhibits high Faradaic efficiency (FE) towards formate production for GOR. A two-electrode electrolyzer exhibits superb activity that only needs an ultralow cell voltage of 1.40 V to achieve 40 mA cm-2 with a high FE (97%) for formate production. Theoretical calculation unravels that the introduction of molybdenum contributes to the deviation of the d-band center of Ni3 Se2 from the Fermi level, which is conducive to hydrogen desorption. Meanwhile, the construction of the heterojunction induces the distortion of the surface structure of nickel selenide, which exposes highly active nickel sites for glycerol adsorption, thus contributing to the excellent electrocatalytic performance.
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Electrochemical conversion of CO2 to highly valuable ethanol has been considered a intriguring strategy for carbon neutruality. However, the slow kinetics of coupling carbon-carbon (C-C) bonds, especially the low selectivity ethanol than ethylene in neutral conditions, is a significant challenge. Herein, the asymmetrical refinement structure with enhanced charge polarization is built in the vertically oriented bimetallic organic frameworks (NiCu-MOF) nanorod array with encapsulated Cu2 O (Cu2 O@MOF/CF), which can induce an intensive internal electric field to increase the C-C coupling for producing ethanol in neutral electrolyte. Particularly, when directly employed Cu2 O@MOF/CF as the self-supporting electrode, the ethanol faradaic efficiency (FEethanol ) could reach maximum 44.3 % with an energy efficiency of 27 % at a low working-potential of -0.615â V versus the reversible hydrogen electrode (vs. RHE) using CO2 -saturated 0.5â M KHCO3 as the electrolyte. Experimental and theoretical studies suggest that the polarization of atomically localized electric fields derived from the asymmetric electron distribution can tune the moderate adsorption of *CO to assist the C-C coupling and reduce the formation energy of H2 CCHO*-to-*OCHCH3 for the generation of ethanol. Our research offers a reference for the design of highly active and selective electrocatalysts for reducing CO2 to multicarbon chemicals.
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Dióxido de Carbono , Carbono , Adsorción , Electricidad , EtanolRESUMEN
As promising hydrogen energy carrier, formic acid (HCOOH) plays an indispensable role in building a complete industry chain of a hydrogen economy. Currently, the biomass upgrading assisted water electrolysis has emerged as an attractive alternative for co-producing green HCOOH and H2 in a cost-effective manner, yet simultaneously affording high current density and Faradaic efficiency (FE) still remains a big challenge. Here, the ternary NiVRu-layered double hydroxides (LDHs) nanosheet arrays for selective glycerol oxidation and hydrogen evolution catalysis are reported, which yield an industry-level 1 A cm-2 at voltage of 1.933 V, meanwhile showing considerable HCOOH and H2 productivities of 12.5 and 17.9 mmol cm-2 h-1 , with FEs of almost 80% and 96%, respectively. Experimental and theoretical results reveal that the introduced Ru atoms can tune the local electronic structure of Ni-based LDHs, which not only optimizes hydrogen adsorption kinetics for HER, but also reduces the reaction energy barriers for both the conversion of NiII into GOR-active NiIII and carboncarbon (CC) bond cleavage. In short, this work highlights the potential of large-scale H2 and HCOOH productions from integrated electrocatalytic system and provides new insights for designing advanced electrocatalyst for low-cost and sustainable energy conversion.