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1.
Proc Natl Acad Sci U S A ; 120(14): e2219043120, 2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-36996112

RESUMEN

Despite the various strategies for achieving metal-nitrogen-carbon (M-N-C) single-atom catalysts (SACs) with different microenvironments for electrochemical carbon dioxide reduction reaction (CO2RR), the synthesis-structure-performance correlation remains elusive due to the lack of well-controlled synthetic approaches. Here, we employed Ni nanoparticles as starting materials for the direct synthesis of nickel (Ni) SACs in one spot through harvesting the interaction between metallic Ni and N atoms in the precursor during the chemical vapor deposition growth of hierarchical N-doped graphene fibers. By combining with first-principle calculations, we found that the Ni-N configuration is closely correlated to the N contents in the precursor, in which the acetonitrile with a high N/C ratio favors the formation of Ni-N3, while the pyridine with a low N/C ratio is more likely to promote the evolution of Ni-N2. Moreover, we revealed that the presence of N favors the formation of H-terminated edge of sp2 carbon and consequently leads to the formation of graphene fibers consisting of vertically stacked graphene flakes, instead of the traditional growth of carbon nanotubes on Ni nanoparticles. With a high capability in balancing the *COOH formation and *CO desorption, the as-prepared hierarchical N-doped graphene nanofibers with Ni-N3 sites exhibit a superior CO2RR performance compared to that with Ni-N2 and Ni-N4 ones.

2.
Hepatology ; 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38899975

RESUMEN

BACKGROUND AND AIMS: Liver hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths worldwide. The heterogeneity of this malignancy is driven by a wide range of genetic alterations, leading to a lack of effective therapeutic options. In this study, we conducted a systematic multi-omics characterization of HCC to uncover its metabolic reprogramming signature. APPROACH AND RESULTS: Through a comprehensive analysis incorporating transcriptomic, metabolomic, and lipidomic investigations, we identified significant changes in metabolic pathways related to glucose flux, lipid oxidation and degradation, and de novo lipogenesis in HCC. The lipidomic analysis revealed abnormal alterations in glycerol-lipids, phosphatidylcholine (PC), and sphingolipid (SL) derivatives. Machine-learning techniques identified a panel of genes associated with lipid metabolism as common biomarkers for HCC across different etiologies. Our findings suggest that targeting phosphatidylcholine with saturated fatty acids (SFA-PC) and long-chain sphingolipid biosynthesis pathways, particularly by inhibiting Lysophosphatidylcholine Acyltransferase 1 (LPCAT1) and Ceramide Synthase 5 (CERS5) as potential therapeutic strategies for HCC in vivo and in vitro. Notably, our data revealed an oncogenic role of CERS5 in promoting tumor progression through lipophagy. CONCLUSION: In conclusion, our study elucidates the metabolic reprogramming gnature of lipid metabolism in HCC, identifies prognostic markers, and therapeutic targets, and highlights potential metabolism-related targets for therapeutic intervention in HCC.

3.
Nano Lett ; 24(18): 5490-5497, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38657179

RESUMEN

The sodium (Na) metal anode encounters issues such as volume expansion and dendrite growth during cycling. Herein, a novel three-dimensional flexible composite Na metal anode was constructed through the conversion-alloying reaction between Na and ultrafine Sb2S3 nanoparticles encapsulated within the electrospun carbon nanofibers (Sb2S3@CNFs). The formed sodiophilic Na3Sb sites and the high Na+-conducting Na2S matrix, coupled with CNFs, establish a spatially confined "sodiophilic-conductive" network, which effectively reduces the Na nucleation barrier, improves the Na+ diffusion kinetics, and suppresses the volume expansion, thereby inhibiting the Na dendrite growth. Consequently, the Na/Sb2S3@CNFs electrode exhibits a high Coulombic efficiency (99.94%), exceptional lifespan (up to 2800 h) at high current densities (up to 5 mA cm-2), and high areal capacities (up to 5 mAh cm-2) in symmetric cells. The coin-type full cells assembled with a Na3V2(PO4)3/C cathode demonstrate significant enhancement in electrochemical performance. The flexible pouch cell achieves an excellent energy density of 301 Wh kg-1.

4.
Proc Natl Acad Sci U S A ; 118(49)2021 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-34857631

RESUMEN

A series of sodium phosphorothioate complexes are shown to have electrochemical properties attractive for sodium-sulfur battery applications across a wide operating temperature range. As cathode materials, they resolve a long-standing issue of cyclic liquid-solid phase transition that causes sluggish reaction kinetics and poor cycling stability in conventional, room-temperature sodium-sulfur batteries. The cathode chemistry yields 80% cyclic retention after 400 cycles at room temperature and a superior low-temperature performance down to -60 °C. Coupled experimental characterization and density functional theory calculations revealed the complex structures and electrochemical reaction mechanisms. The desirable electrochemical properties are attributed to the ability of the complexes to prevent the formation of solid precipitates over a fairly wide range of voltage.

5.
J Am Chem Soc ; 145(34): 18865-18876, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37589666

RESUMEN

Beyond lithium-ion technologies, lithium-sulfur batteries stand out because of their multielectron redox reactions and high theoretical specific energy (2500 Wh kg-1). However, the intrinsic irreversible transformation of soluble lithium polysulfides to solid short-chain sulfur species (Li2S2 and Li2S) and the associated large volume change of electrode materials significantly impair the long-term stability of the battery. Here we present a liquid sulfur electrode consisting of lithium thiophosphate complexes dissolved in organic solvents that enable the bonding and storage of discharge reaction products without precipitation. Insights garnered from coupled spectroscopic and density functional theory studies guide the complex molecular design, complexation mechanism, and associated electrochemical reaction mechanism. With the novel complexes as cathode materials, high specific capacity (1425 mAh g-1 at 0.2 C) and excellent cycling stability (80% retention after 400 cycles at 0.5 C) are achieved at room temperature. Moreover, the highly reversible all-liquid electrochemical conversion enables excellent low-temperature battery operability (>400 mAh g-1 at -40 °C and >200 mAh g-1 at -60 °C). This work opens new avenues to design and tailor the sulfur electrode for enhanced electrochemical performance across a wide operating temperature range.

6.
Artículo en Inglés | MEDLINE | ID: mdl-38141203

RESUMEN

OBJECTIVES: Systemic lupus erythematosus (SLE) is a complex autoimmune disease with varying symptoms and multi-organ damage. Relapse-remission cycles often persist for many patients for years with the current treatment. Improved understanding of molecular changes caused by SLE flare and intensive treatment may result in more targeted therapies. METHODS: RNA-sequencing was performed on peripheral blood mononuclear cells (PBMCs) from 65 SLE patients in flare, collected both before (SLE1) and after (SLE2) in-hospital treatment, along with 15 healthy controls (HC). Differentially expressed genes (DEGs) were identified among the three groups. Enriched functions and key molecular signatures of the DEGs were analyzed and scored to elucidate the transcriptomic changes during treatment. RESULTS: Few upregulated genes in SLE1 vs HC were affected by treatment (SLE2 vs SLE1), mostly functional in interferon signalling (IFN), plasmablasts, and neutrophils. IFN and plasmablast signatures were repressed, but the neutrophil signature remained unchanged or enhanced by treatment. The IFN and neutrophil scores together stratified the SLE samples. IFN scores correlated well with leukopenia, while neutrophil scores reflected relative cell compositions but not cell counts. CONCLUSIONS: In-hospital treatment significantly relieved SLE symptoms with expression changes of a small subset of genes. Notably, IFN signature changes matched SLE flare and improvement, while enhanced neutrophil signature upon treatment suggested the involvement of low-density granulocytes (LDG) in disease development.

7.
Cancer Cell Int ; 23(1): 298, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38012755

RESUMEN

Methyltransferase-like 3 (METTL3) is the key subunit of methyltransferase complex responsible for catalyzing N6-methyladenosine (m6A) modification on mRNA, which is the most prevalent post-transcriptional modification in eukaryotes. In this study, we utilized online databases to analyze the association between METTL3 expression and various aspects of tumorigenesis, including gene methylation, immunity, and prognosis. Our investigation revealed that METTL3 serves as a prognostic marker and therapeutic target for liver hepatocellular carcinoma (LIHC). Through experimental studies, we observed frequent upregulation of METTL3 in LIHC tumor tissue and cells. Subsequent inhibition of METTL3 using a novel small molecule inhibitor, STM2457, significantly impeded tumor growth in LIHC cell lines, spheroids, and xenograft tumor model. Further, transcriptome and m6A sequencing of xenograft bodies unveiled that inhibition of METTL3-m6A altered genes enriched in SMAD and MAPK signaling pathways that are critical for tumorigenesis. These findings suggest that targeting METTL3 represents a promising therapeutic strategy for LIHC.

8.
Genomics ; 114(1): 23-30, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34843903

RESUMEN

HBV integration and function has gradually been expanding. However, the exact mode of HBV integration remains unclear. In our research, the high-throughput long-read sequencing was combined with bioinformatics to study the complete mode of HBV integration in hepatocellular carcinoma (HCC) cells. The results demonstrated that: 1) The HBV insertion sequences of HBV integration events accounted for 49.5% of the total HBV sequences. 2) Short insertion segments with the length of 0-1 kbp accounted for 50% and the long insertion segments (>3 kbp) accounted for 25% of HBV insertion events. 3)There were different HBV insertion length in the breakpoints formed within different regions. 4) The occurrence of HBV integration events was accompanied by more frequent structural variations. 5)Furthermore, multiple HBV integration patterns were confirmed based on complete HBV insertion sequences. Our research not only clarified a variety of perfect HBV integration models but also determined multiple specific features of HBV integration.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis B , Neoplasias Hepáticas , Carcinoma Hepatocelular/genética , ADN Viral , Virus de la Hepatitis B/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Neoplasias Hepáticas/genética , Integración Viral
9.
Nano Lett ; 22(3): 1382-1390, 2022 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-35099190

RESUMEN

Sodium (Na) metal batteries are promising as next-generation energy storage systems due to the high specific capacity of the Na metal anode as well as rich natural abundance and low cost of Na resources. Nevertheless, uncontrolled growth of dendritic/mossy Na arising from the unstable solid-electrolyte interphase (SEI) leads to rapid electrode degradation and severe safety issues. In this work, we introduce cetyltrimethylammonium bromide (CTAB) as an electrolyte additive that enables a synergistic effect from both the CTA+ cation and Br- anion in stabilizing the Na metal anode. Notably, cryogenic transmission electron microscopy is utilized to investigate the effect of the additive, revealing the critical morphology and structure of the SEIs and Na electrodes at the nano/atomic scale. Benefiting fromthe additive, a stable Na anode can be realized at an ultrahigh capacity of 30 mAh cm-2 at 10 mA cm-2 over 400 h.

10.
Nano Lett ; 22(23): 9335-9342, 2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36379039

RESUMEN

By virtue of high theoretical capacity and appropriate lithiation potential, phosphorus is considered as a prospective next-generation anode material for lithium-ion batteries. However, there are some problems hampering its practical application, such as low ionic conductivity and serious volume expansion. Herein, we demonstrated an in situ preoxidation strategy to build a oxidation function layer at phosphorus particle. The oxide layer not only acted as a protective layer to prolong the storage time of phosphorus anode in air but also carbonized N-methyl pyrrolidone and poly (vinylidene fluoride), strengthening the interfacial interaction between phosphorus particles and binder. The oxide layer further induced the formation of a stable solid electrolyte interface with high lithium-ion conductivity. The oxidized P-CNT maintained high specific capacity of 1306 mAh g-1 and 89% capacity after 100 cycles, much higher than that of pristine P-CNT (17.1%). The strategy of in situ oxidation is facile and conducive to the practical application of phosphorus-based anodes.

11.
Nano Lett ; 21(1): 816-822, 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33369431

RESUMEN

Dendrite growth has been severely impeding the implementation of sodium (Na) metal batteries, which is regarded as one of the most promising candidates for next-generation high-energy batteries. Herein, SnO2 quantum dots (QDs) are homogeneously dispersed and fully covered on a 3D carbon cloth scaffold (SnO2-CC) with high affinity to molten Na, given that SnO2 spontaneously initiates alloying reactions with Na and provides low nucleation barrier for Na deposition. Molten Na can be rapidly infused into the SnO2-CC scaffold as a free-standing anode material. Because of the affinity between SnO2 and Na ion, SnO2 QDs can effectively guide Na nucleation and attains site-directed dendrite-free Na deposition when combined with the 3D CC scaffold. This electrochemically stable anode enables almost 400 cycles at ultrahigh current density of 20 mA cm-2 in Na symmetric battery and delivers superior cycling performance and reversible rate capability in Na-Na3V2(PO4)3 full batteries.

12.
Nano Lett ; 21(20): 8664-8670, 2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34618467

RESUMEN

Rechargeable batteries with metallic lithium (Li) anodes are attracting ever-increasing interests because of their high theoretical specific capacity and energy density. However, the dendrite growth of the Li anode during cycling leads to poor stability and severe safety issues. Here, Li3Bi alloy coated carbon cloth is rationally chosen as the substrate of the Li anode to suppress the dendrite growth from a thermodynamic aspect. The adsorption energy of a Li atom on Li3Bi is larger than the cohesive energy of bulk Li, enabling uniform Li nucleation and deposition, while the high diffusion barrier of the Li atom on Li3Bi blocks the migration of adatoms from adsorption sites to the regions of fast growth, which further ensures uniform Li deposition. With the dendrite-free Li deposition, the composite Li/Li3Bi anode enables over 250 cycles at an ultrahigh current density of 20 mA cm-2 in a symmetrical cell and delivers superior electrochemical performance in full batteries.

13.
Biochem Biophys Res Commun ; 553: 160-164, 2021 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-33773138

RESUMEN

Hepatitis B virus (HBV) DNA integration is closely related to the occurrence of liver cancer. However, current studies mostly focus on the detection of the viral integration sites, ignoring the relationship between the frequency of viral integration and liver cancer. Thus, this study uses previous data to distinguish the breakpoints according to the integration frequency and analyzes the characteristics of different groups. This analysis revealed that three sets of breakpoints were characterized by its own integrated sample frequency, breakpoint distribution, and affected gene pathways. This result indicated an evolution in the virus integration sites in the process of tumor formation and development. Therefore, our research clarified the characteristics and differences in the sites of viral integration in tumors and adjacent tissues, and clarified the key signaling pathways affected by viral integration. Hence, these findings might be of great significance in the understanding of the role of viral integration frequency in hepatocellular carcinoma.


Asunto(s)
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virología , Virus de la Hepatitis B/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virología , Integración Viral/genética , Carcinogénesis/genética , Estudios de Casos y Controles , Puntos de Rotura del Cromosoma , Frecuencia de los Genes , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Transducción de Señal/genética
14.
Rheumatology (Oxford) ; 60(9): 4407-4417, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-33493351

RESUMEN

OBJECTIVES: To identify novel genetic loci associated with systemic lupus erythematosus (SLE) and to evaluate potential genetic differences between ethnic Chinese and European populations in SLE susceptibility. METHODS: A new genome-wide association study (GWAS) was conducted from Jining, North China, on 1506 individuals (512 SLE cases and 994 matched healthy controls). The association results were meta-analysed with existing data on Chinese populations from Hong Kong, Guangzhou and Central China, as well as GWAS results from four cohorts of European ancestry. A total of 26 774 individuals (9310 SLE cases and 17 464 controls) were included in this study. RESULTS: Meta-analysis on four Chinese cohorts identifies KLF2 as a novel locus associated with SLE [rs2362475; odds ratio (OR) = 0.85, P=2.00E-09]. KLF2 is likely an Asian-specific locus as no evidence of association was detected in the four European cohorts (OR = 0.98, P =0.58), with evidence of heterogeneity (P=0.0019) between the two ancestral groups. Meta-analyses of results from both Chinese and Europeans identify STAB2 (rs10082873; OR= 0.89, P=4.08E-08) and DOT1L (rs4807205; OR= 1.12, P=8.17E-09) as trans-ancestral association loci, surpassing the genome-wide significance. CONCLUSIONS: We identified three loci associated with SLE, with KLF2 a likely Chinese-specific locus, highlighting the importance of studying diverse populations in SLE genetics. We hypothesize that DOT1L and KLF2 are plausible SLE treatment targets, with inhibitors of DOT1L and inducers of KLF2 already available clinically.


Asunto(s)
Moléculas de Adhesión Celular Neuronal/genética , Predisposición Genética a la Enfermedad , N-Metiltransferasa de Histona-Lisina/genética , Factores de Transcripción de Tipo Kruppel/genética , Polimorfismo de Nucleótido Simple , Adulto , Alelos , Estudios de Casos y Controles , China , Femenino , Frecuencia de los Genes , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Lupus Eritematoso Sistémico/genética , Masculino , Persona de Mediana Edad , Adulto Joven
15.
Chem Soc Rev ; 49(12): 3783-3805, 2020 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-32469031

RESUMEN

Rechargeable sodium (Na) based batteries have gained tremendous research interest because of the high natural abundance and low cost of Na resources, as well as electrochemical similarities with lithium (Li) based batteries. However, despite the great potential as a candidate for next-generation grid-scale energy storage, the implementation of the Na metal anode has been primarily hindered by dendritic and "dead" Na formation that leads to low Coulombic efficiency, short lifespan and even safety concerns. Na dendrite formation mainly originates from the uncontrolled Na deposition behavior in the absence of nucleation site regulation. Hence, the Na nucleation and initial stage of growth are critically important for the final morphology of Na metal. Here, this tutorial review aims to provide a comprehensive understanding of the importance of the nucleation behavior towards dendrite-free Na metal anodes. Firstly, we start with an introduction about the advantages of Na metal batteries over the Li counterpart and the challenges faced by Na metal anodes. The differences between metallic Li and Na are summarized according to advanced in situ characterization techniques. Next, we elucidate the key factors that influence the Na nucleation and growth behaviors based on the existing theoretical models. Then, we review the state-of-the-art approaches that have been applied to effectively regulate Na nucleation for dendrite-free Na deposition. Lastly, we conclude the review with perspectives on realizing safe Na metal batteries with high energy density.

16.
Nano Lett ; 20(10): 7700-7708, 2020 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-32931696

RESUMEN

Although sodium (Na) is one of the most promising alternatives to lithium as an anode material for next-generation batteries, uncontrollable Na dendrite growth still remains the main challenge for Na metal batteries. Herein, a novel 1D/2D Na3Ti5O12-MXene hybrid nanoarchitecture consisting of Na3Ti5O12 nanowires grown between the MXene nanosheets is synthesized by a facile approach using cetyltrimethylammonium bromide (CTAB)-pretreated Ti3C2 MXene. Used as a matrix for the Na metal anode, the Na3Ti5O12 nanowires, formed benefiting from the CTAB stabilization, have chemical interaction with Na and thus provide abundant Na nucleation sites. These 1D nanostructures, together with the unique confinement effect from the 2D nanosheets, effectively guide and control the Na deposition within the interconnected nanochannels, preventing the "hot spot" formation for dendrite growth. A stable cycling performance can be achieved at a high current density up to 10 mA cm-2 along with an ultrahigh capacity up to 20 mAh cm-2.

17.
Nano Lett ; 20(5): 3620-3626, 2020 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-32212736

RESUMEN

All-solid-state sodium-carbon dioxide (Na-CO2) battery is an emerging technology that effectively utilizes the greenhouse gas, CO2, for energy storage with the virtues of minimized electrolyte leakage and suppressed Na dendrite growth for the Na metal anode. However, the sluggish reduction/evolution reactions of CO2 on the solid electrolyte/CO2 cathode interface have caused premature battery failure. Herein, nitrogen (N)-doped nanocarbon derived from metal-organic frameworks is designed as a cathode catalyst to solve this challenge. The porous and highly conductive N-doped nanocarbon possesses superior uptake and binding capability with CO2, which significantly accelerates the CO2 electroreduction and promotes the formation of thin sheetlike discharged products (200 nm in thickness) that can be easily decomposed upon charging. Accordingly, reduced discharge/charge overpotential, high discharge capacity (>10 000 mAh g-1), long cycle life, and high energy density (180 Wh kg-1 in pouch cells) are achieved at 50 °C.

18.
Angew Chem Int Ed Engl ; 60(11): 5978-5983, 2021 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-33258244

RESUMEN

Enabling high-performing alkali metal anodes at low temperature and in lean electrolyte conditions is critical for the advancement of next-generation batteries with high energy density and improved safety. We present an ether-ionic liquid composite electrolyte to tackle the problem of dendrite growth of metallic sodium anode at low temperatures ranging from 0 to -40 °C. This composite electrolyte enables a stable sodium metal anode to be deeply cycled at 2 mA cm-2 with an ultrahigh reversible capacity of 50 mAh cm-2 for 500 hours at -20 °C in lean electrolyte (1.0 µL mAh-1 ) conditions. Using the composite electrolyte, full cells with Na3 V2 (PO4 )3 as cathode and sodium metal as anode present a high capacity retention of 90.7 % after 1,000 cycles at 2C at -20 °C. The sodium-carbon dioxide batteries also exhibit a reversible capacity of 1,000 mAh g-1 over 50 cycles across a range of temperatures from -20 to 25 °C.

19.
J Am Chem Soc ; 142(52): 21656-21669, 2020 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-33305565

RESUMEN

The use of reticular materials in the electrochemical reduction of carbon dioxide to value-added products has the potential to enable tunable control of the catalytic performance through the modulation of chemical and structural features of framework materials with atomic precision. However, the tunable functional performance of such systems is still largely hampered by their poor electrical conductivities. This work demonstrates the use of four systematic structural analogs of conductive two-dimensional (2D) metal-organic frameworks (MOFs) made of metallophthalocyanine (MPc) ligands linked by Cu nodes with electrical conductivities of 2.73 × 10-3 to 1.04 × 10-1 S cm-1 for the electrochemical reduction of CO2 to CO. The catalytic performance of the MOFs, including the activity and selectivity, is found to be hierarchically governed by two important structural factors: the metal within the MPc (M = Co vs Ni) catalytic subunit and the identity of the heteroatomic cross-linkers between these subunits (X = O vs NH). The activity and selectivity are dominated by the choice of metal within MPcs and are further modulated by the heteroatomic linkages. Among these MOFs, CoPc-Cu-O exhibited the highest selectivity toward CO product (Faradaic efficiency FECO = 85%) with high current densities up to -17.3 mA cm-2 as a composite with carbon black at 1:1 mass ratio) at a low overpotential of -0.63 V. Without using any conductive additives, the use of CoPc-Cu-O directly as an electrode material was able to achieve a current density of -9.5 mA cm-2 with a FECO of 79%. Mechanistic studies by comparison tests with metal-free phthalocyanine MOF analogs supported the dominant catalytic role of the central metal of the phthalocyanine over Cu nodes. Density-functional theory calculations further suggested that, compared with the NiPc-based and NH-linked analogs, CoPc-based and O-linked MOFs have lower activation energies in the formation of carboxyl intermediate, in line with their higher activities and selectivity. The results of this study indicate that the use of 2D MPc-based conductive framework materials holds great promise for achieving efficient CO2 reduction through strategic ligand engineering with multiple levels of tunability.

20.
Nano Lett ; 19(6): 3925-3932, 2019 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-31034237

RESUMEN

Electrochemical reduction of carbon dioxide (CO2) into value-added chemicals and fuels provides a promising pathway for environmental and energy sustainability. Copper (Cu) demonstrates a unique ability to catalyze the electrochemical conversion of CO2 into valuable multicarbon products. However, developing a rapid, scalable and cost-effective method to synthesize efficient and stable Cu catalysts with high selectivity toward multicarbon products at a low overpotential is still hard to achieve and highly desirable. In this work, we present a facile wet chemistry approach to yield well-defined cuprous halide (CuX, X = Cl, Br or I) microcrystals with different degrees of truncations at edges/vertices, which can be ascribed to the oxidative etching mechanism of halide ions. More importantly, the as-obtained cuprous halides can be electrochemically transformed into varied Cu nanoarchitectures, thus exhibiting distinct CO2 reduction behaviors. The CuI-derived Cu nanofibers composed of self-assembled nanoparticles are reported for the first time, which favor the formation of C2+3 products at a low overpotential with a particular selectivity toward ethane. In comparison, the Cu nanocubes evolved from CuCl are highly selective toward C1 products. For CuBr-derived Cu nanodendrites, C1 products are subject to form at a low overpotential, while C2+3 products gradually become dominant with a favorable formation of ethylene when the potential turns more negative. This work explicitly reveals the critical morphology effect of halide-derived Cu nanostructures on the CO2 product selectivity, and also provides an ideal platform to investigate the structure-property relationship for CO2 electroreduction.

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