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1.
Chem Biodivers ; 21(5): e202301741, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38477870

RESUMO

Diabetes mellitus is an endocrine disease characterized by prolonged hyperglycemia. Prolonged high blood sugar levels interfere with the differentiation and maturation process of OBs and OCs, leading to the onset of osteoporosis. However, OCs differentiation and maturation is a complex regulatory process. In this study, we used a co-culture system of RAW264.7 and MC3T3-E1 cells under HG concentration to explore the effect of CYM on OCs in a HG environment. The effects of CYM on the formation and function of OCs were observed using TRAP-positive cell counts and bone resorption pits. Then, mRNA and protein expression levels of OCs-related genes were detected by real-time qPCR and western blotting. The results showed that CYM had an inhibitory effect on OCs differentiation and bone resorption, reduced mRNAs expression of OCs-associated genes, and downregulated RANKL/RANK/TRAF6 pathway that mediates OCs differentiation. CYM could be a promising natural compound against diabetic osteoporosis.


Assuntos
Diferenciação Celular , Glucose , Osteoclastos , Ligante RANK , Animais , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteoclastos/citologia , Camundongos , Glucose/metabolismo , Glucose/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células RAW 264.7 , Ligante RANK/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Células Cultivadas , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/genética , Relação Dose-Resposta a Droga , Reabsorção Óssea/metabolismo , Reabsorção Óssea/tratamento farmacológico
2.
J Am Chem Soc ; 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37021910

RESUMO

Electrocatalytic carbon dioxide reduction (CO2R) in neutral electrolytes can mitigate the energy and carbon losses caused by carbonate formation but often experiences unsatisfied multicarbon selectivity and reaction rates because of the kinetic limitation to the critical carbon monoxide (CO)-CO coupling step. Here, we describe that a dual-phase copper-based catalyst with abundant Cu(I) sites at the amorphous-nanocrystalline interfaces, which is electrochemically robust in reducing environments, can enhance chloride-specific adsorption and consequently mediate local *CO coverage for improved CO-CO coupling kinetics. Using this catalyst design strategy, we demonstrate efficient multicarbon production from CO2R in a neutral potassium chloride electrolyte (pH ∼6.6) with a high Faradaic efficiency of 81% and a partial current density of 322 milliamperes per square centimeter. This catalyst is stable after 45 h of operation at current densities relevant to commercial CO2 electrolysis (300 mA per square centimeter).

3.
Org Biomol Chem ; 21(23): 4881-4892, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37259536

RESUMO

An aminomethylation reaction of fulleropyrrolidines bearing ketone moieties in the presence of N-unsubstituted fulleropyrrolidines and paraformaldehyde with the aid of p-toluenesulfonic acid afforded a series of scarce pendant fullerene dimers. A simple change of reaction substrates from ketone to ketone-containing fulleropyrrolidines successfully realized the synthesis of a variety of novel pendant fullerene dimers, including those from methyl ketone-containing fulleropyrrolidines, which were considered to produce the known bridged fullerene dimers. It should be noted that pendant fullerene dimers are usually difficult to prepare by other methods and may have promising applications in perovskite solar cells. Density functional theory (DFT) has been employed to elucidate the regioselectivity of methyl ketone-containing fulleropyrrolidines to yield exclusively pendant fullerene dimers by investigating the Gibbs free energy profile of the reaction starting from methyl ketone-containing fulleropyrrolidines and iminium intermediates.

4.
J Nat Prod ; 86(10): 2348-2359, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37737089

RESUMO

Eleven diterpenoids, wulfenioidins D-N (1-11), classified into five distinct carbon skeletons with one unreported framework, and four modified abietane diterpenoids were isolated from the whole plant of Orthosiphon wulfenioides. The structures and absolute configurations were characterized by spectroscopic methods, single-crystal X-ray diffraction, and electronic circular dichroism analyses. Compounds 3 and 5 exhibited activity against Zika virus (ZIKV) with EC50 values of 8.07 and 8.50 µM, respectively, and showed no significant cytotoxicity toward Vero cells at 100 µM. Western blot and immunofluorescence experiments showed that compounds 3 and 5 interfered with the replication of the ZIKV by inhibiting the expression of the ZIKV envelope (E) protein.


Assuntos
Diterpenos , Orthosiphon , Infecção por Zika virus , Zika virus , Animais , Chlorocebus aethiops , Células Vero , Diterpenos/química , Estrutura Molecular
5.
Artigo em Inglês | MEDLINE | ID: mdl-35137675

RESUMO

PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) have been proved to be hazardous to health. Previous studies have focused on the distribution and sources of PAHs, whereas there is little knowledge of the damage to organs. Here we sought to investigate the pollution level and seasonal variation characteristics of PAHs in PM2.5 in Xi'an and assess the health risk, to establish a PAHs exposure model, and investigate the toxicological effects of PAHs on the respiratory and immune functions. A sub-chronic exposure model of PAHs was established by inhalation. The pathological changes of lung tissues were observed with a light microscope. Inflammatory reactions in alveolar lavage fluid were determined using the corresponding kit. The levels of interleukin-6 (IL-6) and interleukin-8 (IL-8) were detected with enzyme linked immunosorbent assay (ELISA) kit; the proliferation of lymphocytes in spleen was detected with methyl tetrazolium (MTT); DNA immune damage was determined with DNA gel electrophoresis. The results showed that (1) the total concentration of 16 PAHs ranged from 41.1 to 387 ng/m3, with a mean value of 170 ng/m3, and the concentration of PAHs in PM2.5 was higher in winter than in other seasons. (2) The sources of PAHs in the atmosphere of Xi'an urban area were mainly coal combustion, and the equivalent carcinogenic concentration of PAHs in PM2.5 was 3.9 ng/m3. (3) Foreign body granuloma formation and inflammatory cell damage were observed in the lungs of rats infected with toxin; the levels of reactive oxygen species (ROS) and mobile device assistant (MDA) increased while nitric oxide synthase (NOS) decreased with the increase of dose; the expression levels of IL-6 and IL-8 elevated with the increase of toxin dose, showing an obvious dose-effect relationship; the level of PAHs damage to cells showed a dose-effect relationship. Sub-chronic exposure to PAHs could cause sustained inflammatory injury to the organism. Measures should be taken to counter the problems of PAHs in PM2.5 in Xi'an and relevant health promotion strategies should be developed.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Animais , Ratos , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Estações do Ano , Interleucina-8 , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Interleucina-6/análise , Baço , Material Particulado/toxicidade , Material Particulado/análise , China , Medição de Risco
6.
Angew Chem Int Ed Engl ; 62(49): e202314539, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37880874

RESUMO

The semiconducting properties and applications of three dimensional (3D) covalent organic frameworks (COFs) are greatly hampered because of their long-ranged non-conjugated skeletons and relatively unstable linkages. Here, a robust imidazole-linked fully conjugated 3D covalent organic framework (BUCT-COF-7) is synthesized through the one-pot multicomponent Debus-Radziszewski reaction of the saddle-shaped aldehyde-substituted cyclooctatetrathiophene, pyrene-4,5,9,10-tetraone, and ammonium acetate. The semiconducting BUCT-COF-7, as a metal-free catalyst, shows excellent two electron oxygen reduction reaction (ORR) activity in alkaline medium with high hydrogen peroxide (H2 O2 ) selectivity of 83.4 %. When the BUCT-COF-7 as cathode catalyst is assembled into the electrolyzer, the devices showed high electrochemical production rate of H2 O2 up to 326.9 mmol g-1 h-1 . The accumulative amount of H2 O2 could totally degrade the dye methylene blue via Fenton reaction for wastewater treatment. This is the first report about intrinsic 3D COFs for efficient electrochemical synthesis of H2 O2 , revealing the promising applications of fully conjugated 3D COFs in the environment-related field.

7.
Org Biomol Chem ; 20(23): 4681-4698, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35617020

RESUMO

Salicyloylbenzene/heterocycles are privileged scaffolds found in many natural products and bioactive molecules. Numerous useful approaches for the preparation of these privileged scaffolds have been developed in recent years. Among these approaches, chromone-based reactants have demonstrated their importance in the synthesis of these salicyloylbenzene/heterocycle scaffolds with structural complexity and potential biological appeal. In this review, the recent advances in the synthesis of salicyloylbenzene/heterocycles are summarized and discussed according to the chromone-based reactants which could be achieved in one step via ring-opening and skeletal reconstruction reactions. Both the mechanisms and the applications of the corresponding products in organic and medicinal chemistry are also described.


Assuntos
Química Farmacêutica , Cromonas
8.
Asia Pac J Clin Nutr ; 31(4): 748-752, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36576291

RESUMO

BACKGROUND AND OBJECTIVES: Vitamin A is vital for the growth and health of children. This study aimed to estimate the current vitamin A status and the prevalence of vitamin A deficiency (VAD) among preschool children and explore the correlation between serum vitamin A concentration and changes in hematological parameters. METHODS AND STUDY DESIGN: The study included 697 children aged 1-6 years, presenting for routine checkups at the Department of Pediatrics, Peking University Shougang Hospital, Beijing, from April 2017 to December 2020. We obtained the complete laboratory test data of 630 children. RESULTS: The mean serum vitamin A concentration among preschool children was 0.29±0.08 mg/L, with a median of 0.29 mg/L. The proportion of children with VAD and marginal VAD (MVAD) was 9.84% and 43.49%, respectively. The highest prevalence of VAD and MVAD was in the 3- to 4-year age group. Compared with the normal vitamin A serum concentration group, other groups had lower mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and higher red blood cell distribution width. The mean serum vitamin A concentration among anemic children was significantly lower (0.27±0.07 mg/L) than among those children who were not anemic (p<0.05). CONCLUSIONS: VAD constitutes a public health problem in northern China. The prevalence of VAD is highest, and the serum vitamin A concentration was the lowest among preschool children aged 3-4 years. Vitamin A serum concentration was associated with red blood cell indices. We should attach more importance to those children aged 3-4 years.


Assuntos
Anemia , Deficiência de Vitamina A , Criança , Humanos , Pré-Escolar , Vitamina A , Pequim/epidemiologia , Deficiência de Vitamina A/epidemiologia , China/epidemiologia , Anemia/epidemiologia , Prevalência
9.
J Asian Nat Prod Res ; 24(12): 1157-1168, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35435096

RESUMO

Hyperoside (HP), as a natural product, can promote proliferation and differentiation of osteoblasts and presents a protective effect on ovariectomized (OVX) mice. However, the inhibitory effect of HP on osteoclasts (OCs) and the potential mechanism remain to be elucidated. In this study, it was found that HP could effectively inhibit the differentiation and bone resorption of OCs, and its intrinsic molecular mechanism was related to the inhibition of TRAF6/p38 MAPK signaling pathway. Therefore, HP could be a promising natural compound for lytic bone diseases.


Assuntos
Osteoclastos , Fator 6 Associado a Receptor de TNF , Camundongos , Animais , Osteoclastos/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Fator 6 Associado a Receptor de TNF/farmacologia , Ligante RANK/farmacologia , Ligante RANK/metabolismo , Estrutura Molecular , Sistema de Sinalização das MAP Quinases , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Diferenciação Celular , Osteogênese
10.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(1): 78-84, 2022 Jan 15.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-35177180

RESUMO

OBJECTIVES: To study the efficacy and safety of early intratracheal administration of budesonide combined with pulmonary surfactant (PS) in preventing bronchopulmonary dysplasia (BPD). METHODS: A prospective randomized controlled trial was designed. A total of 122 infants with a high risk of BPD who were admitted to the neonatal intensive care unit of the Third Affiliated Hospital of Zhengzhou University from January to July 2021 were enrolled. The infants were randomly divided into a conventional treatment group with 62 infants (treated with PS alone at an initial dose of 200 mg/kg, followed by a dose of 100 mg/kg according to the condition of the infant) and an observation group with 60 infants (treated with PS at the same dose as the conventional treatment group, with the addition of budesonide 0.25 mg/kg for intratracheal instillation at each time of PS application). The two groups were compared in terms of the times of PS use, ventilator parameters at different time points, oxygen inhalation, incidence rate and severity of BPD, incidence rate of complications, and tidal breathing pulmonary function at the corrected gestational age of 40 weeks. RESULTS: Compared with the conventional treatment group, the observation group had a significantly lower proportion of infants using PS for two or three times (P<0.05). Compared with the conventional treatment group, the observation group had a significantly lower fraction of inspired oxygen at 24 and 48 hours and 3, 7, and 21 days after administration, significantly shorter durations of invasive ventilation, noninvasive ventilation, ventilator application, and oxygen therapy, a significantly lower incidence rate of BPD, and a significantly lower severity of BPD (P<0.05). There was no significant difference in the incidence rate of glucocorticoid-related complications between the two groups (P>0.05). CONCLUSIONS: Compared with PS use alone in preterm infants with a high risk of BPD, budesonide combined with PS can reduce repeated use of PS, lower ventilator parameters, shorten the duration of respiratory support, and reduce the incidence rate and severity of BPD, without increasing the incidence rate of glucocorticoid-related complications.


Assuntos
Displasia Broncopulmonar , Surfactantes Pulmonares , Síndrome do Desconforto Respiratório do Recém-Nascido , Displasia Broncopulmonar/tratamento farmacológico , Displasia Broncopulmonar/prevenção & controle , Budesonida , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Estudos Prospectivos , Surfactantes Pulmonares/uso terapêutico , Respiração Artificial , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia
11.
Org Biomol Chem ; 19(10): 2269-2276, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33624683

RESUMO

A methanesulfonylation reaction for the synthesis of sulfone-containing tetrasubstituted carbon stereocenters is described for the first time by simple treatment of indanedione-chromanone synthons with Et3N and easily accessible MsCl without any use of organometallic chemistry. This technology gave the corresponding valuable chromone-based 2-methanesulfonylated 1,3-indanediones in good yields (up to 89% yield) under mild conditions. The present work provides an attractive strategy for the construction of biologically interesting sulfone-containing tetrasubstituted carbon stereocenters, which might be valuable in medicinal chemistry.

12.
Med Sci Monit ; 27: e930369, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34253706

RESUMO

BACKGROUND Fentanyl-induced cough (FIC) during general anesthesia induction and postoperative nausea and vomiting are common complications, yet the risk factors for FIC remain controversial. This retrospective study was conducted at a single center in China and aimed to investigate the risk factors for fentanyl-induced cough following general anesthesia in adults. MATERIAL AND METHODS A total of 601 adult patients undergoing elective surgery were enrolled, and the incidence of FIC during general anesthesia induction and postoperative adverse events were recorded. The risk factors for FIC during general anesthesia induction and postoperative nausea and vomiting were assessed using multivariate logistic regression analysis. RESULTS The incidence of FIC, nausea, and vomiting were 21.8%, 6.3%, and 4.5%, respectively. The results of multivariate logistic regression analysis indicated that pharyngitis history was associated with an increased risk of FIC during general anesthesia induction (odds ratio [OR]: 2.852; 95% confidence interval [CI]: 1.698-4.792; P<0.001), whereas use of lidocaine could protect against FIC risk (OR: 0.649; 95% CI: 0.557-0.757; P<0.001). However, the characteristics of patients were not associated with the risk of postoperative nausea and vomiting. CONCLUSIONS The findings from this study showed that a history of pharyngitis increased the risk of FIC, while the use of lidocaine was associated with a reduced risk of FIC. The risk of postoperative nausea and vomiting was not affected by fentanyl use or patient characteristics.


Assuntos
Adjuvantes Anestésicos/efeitos adversos , Anestesia Geral , Tosse/induzido quimicamente , Fentanila/efeitos adversos , Administração Intravenosa , Adulto , Anestésicos Intravenosos , Procedimentos Cirúrgicos Eletivos , Humanos , Incidência , Lidocaína , Pessoa de Meia-Idade , Razão de Chances , Náusea e Vômito Pós-Operatórios , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
13.
Angew Chem Int Ed Engl ; 60(25): 14124-14130, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-33856098

RESUMO

We report that continuous MOF films with highly controlled thickness (from 44 to 5100 nm) can be deposited over length scales greater than 80 centimeters by a facile, fast, and cost-effective spray-coating method. Such success relies on our discovery of unprecedented perfectly dispersed colloidal solutions consisting of amorphous MOF nanoparticles, which we adopted as precursors that readily converted to the crystalline films upon low-temperature in situ heating. The colloidal solutions allow for the fabrication of compact and uniform MOF films on a great deal of substrates such as fluorine-doped tin oxide, glass, SiO2 , Al2 O3 , Si, Cu, and even flexible polycarbonate, widening their technological applications where substrates are essential. Despite the present work focuses on the fabrication of uniform cobalt-(2-methylimidazole)2 and zinc-(2-methylimidazole)2 films, our findings mark a great possibility in producing other high-quality MOF thin films on a large scale.

14.
J Am Chem Soc ; 142(13): 6400-6408, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32176485

RESUMO

Selective and efficient catalytic conversion of carbon dioxide (CO2) into value-added fuels and feedstocks provides an ideal avenue to high-density renewable energy storage. An impediment to enabling deep CO2 reduction to oxygenates and hydrocarbons (e.g., C2+ compounds) is the difficulty of coupling carbon-carbon bonds efficiently. Copper in the +1 oxidation state has been thought to be active for catalyzing C2+ formation, whereas it is prone to being reduced to Cu0 at cathodic potentials. Here we report that catalysts with nanocavities can confine carbon intermediates formed in situ, which in turn covers the local catalyst surface and thereby stabilizes Cu+ species. Experimental measurements on multihollow cuprous oxide catalyst exhibit a C2+ Faradaic efficiency of 75.2 ± 2.7% at a C2+ partial current density of 267 ± 13 mA cm-2 and a large C2+-to-C1 ratio of ∼7.2. Operando Raman spectra, in conjunction with X-ray absorption studies, confirm that Cu+ species in the as-designed catalyst are well retained during CO2 reduction, which leads to the marked C2+ selectivity at a large conversion rate.

15.
Bioorg Med Chem Lett ; 30(9): 127087, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32160978

RESUMO

The first example of Ca(OH)2-activated p-regioselective synthesis of chrysin-fused chromene was reported through a cascade Michael/cyclization of chrysin and arylidenemalononitrile. The newly synthesized structurally diverse 2-amino 3-cyano chromene-chrysin hybrids 3 were evaluated for their in vitro anticancer activity, and some of the compounds showed stronger anti-proliferative activity against K562, PC-3, A549 and NCI-H1299 than parent compound chrysin, and demonstrated equipotent potency compared with the reference drug of cisplatin. In particular, compound 3h had the highest cytotoxicity towards K562 cells (IC50 = 6.41 µM). Furthermore, compound 3h induced apoptosis of K562 cells in a concentration-dependent manner, as well as induced the apoptosis possibly through promoting the formation of apoptotic DNA of cancer cell via the intrinsic apoptotic pathway. Thus, our results provide in vitro evidence that compound 3h may be a potential candidate for the development of new anti-tumour drugs.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Benzopiranos/química , Flavonoides/química , Antineoplásicos/química , Linhagem Celular Tumoral , Cisplatino/farmacologia , Descoberta de Drogas , Humanos , Estrutura Molecular
16.
Org Biomol Chem ; 18(44): 9039-9043, 2020 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-33141141

RESUMO

A set of cascade benzannulations of readily accessible chromone-3-carboxaldehydes and γ-nitroaldehydes for synthesizing biologically relevant 2-hydroxybenzophenones has been developed. The cascade was found to provide a transition-metal-free strategy for synthesizing 2-hydroxybenzophenones in acceptable yields (up to 57%).


Assuntos
Benzofenonas
17.
Org Biomol Chem ; 18(38): 7649-7655, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-32966527

RESUMO

To reveal the factors governing the chirality transfer from a chiral unimolecule to a supramolecular assembly, we constructed a series of [2]pseudorotaxanes through the intermolecular noncovalent interaction of a pair of chiral binaphthalene crown ethers with achiral secondary ammonium salts with different chromophores, and found that the binaphthalene groups can induce new circular dichroism (CD) signals only in the [2]pseudorotaxane structures between the host crown ethers and the guest molecule with the anthryl group. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations show that the generation of the new CD signal is mainly due to the intermolecular chiral induction between the anthryl group in the guest and the naphthalene groups in the host.

18.
Org Biomol Chem ; 18(35): 6866-6880, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32844859

RESUMO

A series of scarce amino-substituted cyclopentafullerenes instead of the expected N-alkyl-2,5-disubstituted fulleropyrrolidines were synthesized in moderate to excellent yields via the simple one-step reaction of [60]fullerene with cheap and easily available ß-substituted propionaldehydes and secondary amines in the absence/presence of magnesium perchlorate. The in situ generation of allylic amines from ß-substituted propionaldehydes and secondary amines played a crucial role in the successful preparation of amino-substituted cyclopentafullerenes without additional carbons. With the addition of magnesium perchlorate, secondary amines containing ethyl group(s) could produce novel amino-substituted cyclopentafullerenes with two additional carbons. All the obtained cyclopentafullerenes displayed high stereoselectivity with cis isomers as the exclusive or major products. Plausible reaction mechanisms are proposed to elucidate the above-mentioned reaction process.

19.
Org Biomol Chem ; 18(5): 964-974, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-31930265

RESUMO

A facile one-step reaction of [60]fullerene with cinnamaldehydes and amines promoted by magnesium perchlorate/ferric perchlorate under air conditions afforded a series of rare amino-substituted cyclopentafullerenes in moderate to good yields. Stereoselectivity was readily achieved. Secondary amines exclusively produced N,N-disubstituted cyclopentafullerenes as cis isomers, while arylamines gave N-monosubstituted cyclopentafullerenes with a preference of cis isomers as major products. N-Monosubstituted cyclopentafullerenes could be further converted into other scarce cyclopentafullerenes in the presence of acid chloride or paraformaldehyde. A possible reaction pathway was proposed to elucidate the formation of amino-substituted cyclopentafullerenes.

20.
Angew Chem Int Ed Engl ; 59(22): 8706-8712, 2020 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-31884699

RESUMO

A considerable challenge in the conversion of carbon dioxide into useful fuels comes from the activation of CO2 to CO2 .- or other intermediates, which often requires precious-metal catalysts, high overpotentials, and/or electrolyte additives (e.g., ionic liquids). We report a microwave heating strategy for synthesizing a transition-metal chalcogenide nanostructure that efficiently catalyzes CO2 electroreduction to carbon monoxide (CO). We found that the cadmium sulfide (CdS) nanoneedle arrays exhibit an unprecedented current density of 212 mA cm-2 with 95.5±4.0 % CO Faraday efficiency at -1.2 V versus a reversible hydrogen electrode (RHE; without iR correction). Experimental and computational studies show that the high-curvature CdS nanostructured catalyst has a pronounced proximity effect which gives rise to large electric field enhancement, which can concentrate alkali-metal cations resulting in the enhanced CO2 electroreduction efficiency.

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