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1.
Small ; 17(29): e2101573, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34137160

RESUMO

Single-phase perovskite oxides that contain nonprecious metals have long been pursued as candidates for catalyzing the oxygen evolution reaction, but their catalytic activity cannot meet the requirements for practical electrochemical energy conversion technologies. Here a cation deficiency-promoted phase separation strategy to design perovskite-based composites with significantly enhanced water oxidation kinetics compared to single-phase counterparts is reported. These composites, self-assembled from perovskite precursors, comprise strongly interacting perovskite and related phases, whose structure, composition, and concentration can be accurately controlled by tailoring the stoichiometry of the precursors. The composite catalyst with optimized phase composition and concentration outperforms known perovskite oxide systems and state-of-the-art catalysts by 1-3 orders of magnitude. It is further demonstrated that the strong interfacial interaction of the composite catalysts plays a key role in promoting oxygen ionic transport to boost the lattice-oxygen participated water oxidation. These results suggest a simple and viable approach to developing high-performance, perovskite-based composite catalysts for electrochemical energy conversion.

2.
Angew Chem Int Ed Engl ; 60(13): 7418-7425, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33372346

RESUMO

A rational design for oxygen evolution reaction (OER) catalysts is pivotal to the overall efficiency of water electrolysis. Much work has been devoted to understanding cation leaching and surface reconstruction of very active electrocatalysts, but little on intentionally promoting the surface in a controlled fashion. We now report controllable anodic leaching of Cr in CoCr2 O4 by activating the pristine material at high potential, which enables the transformation of inactive spinel CoCr2 O4 into a highly active catalyst. The depletion of Cr and consumption of lattice oxygen facilitate surface defects and oxygen vacancies, exposing Co species to reconstruct into active Co oxyhydroxides differ from CoOOH. A novel mechanism with the evolution of tetrahedrally coordinated surface cation into octahedral configuration via non-concerted proton-electron transfer is proposed. This work shows the importance of controlled anodic potential in modifying the surface chemistry of electrocatalysts.

3.
Small ; 16(20): e2001204, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32309914

RESUMO

The oxygen evolution reaction (OER) is pivotal in multiple gas-involved energy conversion technologies, such as water splitting, rechargeable metal-air batteries, and CO2 /N2 electrolysis. Emerging anion-redox chemistry provides exciting opportunities for boosting catalytic activity, and thus mastering lattice-oxygen activation of metal oxides and identifying the origins are crucial for the development of advanced catalysts. Here, a strategy to activate surface lattice-oxygen sites for OER catalysis via constructing a Ruddlesden-Popper/perovskite hybrid, which is prepared by a facile one-pot self-assembly method, is developed. As a proof-of-concept, the unique hybrid catalyst (RP/P-LSCF) consists of a dominated Ruddlesden-Popper phase LaSr3 Co1.5 Fe1.5 O10-δ (RP-LSCF) and second perovskite phase La0.25 Sr0.75 Co0.5 Fe0.5 O3-δ (P-LSCF), displaying exceptional OER activity. The RP/P-LSCF achieves 10 mA cm-2 at a low overpotential of only 324 mV in 0.1 m KOH, surpassing the benchmark RuO2 and various state-of-the-art metal oxides ever reported for OER, while showing significantly higher activity and stability than single RP-LSCF oxide. The high catalytic performance for RP/P-LSCF is attributed to the strong metal-oxygen covalency and high oxygen-ion diffusion rate resulting from the phase mixture, which likely triggers the surface lattice-oxygen activation to participate in OER. The success of Ruddlesden-Popper/perovskite hybrid construction creates a new direction to design advanced catalysts for various energy applications.

4.
Small ; 16(51): e2006800, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33251694

RESUMO

Exploring active, stable, and low-cost bifunctional electrocatalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is crucial for water splitting technology associated with renewable energy storage in the form of hydrogen fuel. Here, a newly designed antiperovskite-based hybrid composed of a conductive InNNi3 core and amorphous InNi(oxy)hydroxide shell is first reported as promising OER/HER bifunctional electrocatalyst. Prepared by a facile electrochemical oxidation strategy, such unique hybrid (denoted as EO-InNNi3 ) exhibits excellent OER and HER activities in alkaline media, benefiting from the inherent high-efficiency HER catalytic nature of InNNi3 antiperovskite and the promoting role of OER-active InNi(oxy)hydroxide thin film, which is confirmed by theoretical simulations and in situ Raman studies. Moreover, an alkaline electrolyzer integrated EO-InNNi3 as both anode and cathode delivers a low voltage of 1.64 V at 10 mA cm-2 , while maintaining excellent durability. This work demonstrates the application of antiperovskite-based materials in the field of overall water splitting and inspires insights into the development of advanced catalysts for various energy applications.

5.
Electrophoresis ; 39(17): 2218-2227, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29869395

RESUMO

A rapid, simple, and efficient sample extraction method based on micro-matrix-solid-phase dispersion (micro-MSPD) was applied to the extraction of polyphenols from pomegranate peel. Five target analytes were determined by ultra-HPLC coupled with Q-TOF/MS. Carbon molecular sieve (CMS) was firstly used as dispersant to improve extraction efficiency in micro-MSPD. The major micro-MSPD parameters, such as type of dispersant, amount of dispersant, grinding time, and the type and the volume of elution solvents, were studied and optimized. Under optimized conditions, 26 mg of pomegranate peel was dispersed with 32.5 mg of CMS, the grinding time was selected as 90 s, the dispersed sample was eluted with 100 µL of methanol. Results showed that the proposed method was of good linearity for concentrations of analytes against their peak areas (coefficient of determination r2 > 0.990), the LOD was as low as 3.2 ng/mL, and the spiking recoveries were between 88.1 and 106%. Satisfactory results were obtained for the extraction of gallic acid, punicalagin A, punicalagin B, catechin, and ellagic acid from pomegranate peel sample, which demonstrated nice reliability and high sensitivity of this approach.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Lythraceae/química , Espectrometria de Massas/métodos , Polifenóis/isolamento & purificação , Extração em Fase Sólida/métodos , Carbono/química , Limite de Detecção , Modelos Lineares , Extratos Vegetais/química , Polifenóis/análise , Polifenóis/química , Reprodutibilidade dos Testes
6.
J Sep Sci ; 41(19): 3677-3685, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30058774

RESUMO

A miniaturized solid-phase method was proposed for the extraction of aflatoxin M1 and B1 from milk and jujube samples. Target analytes were identified by ultra high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry in positive mode. The main factors that affected the extraction ability and sensitivity of the analytical method were evaluated in detail. In the optimal conditions, 30 mg of silica particles functionalized with octadecyltrimethoxysilane and methanol were used as sorbent and desorption solvent in miniaturized solid-phase extraction, respectively. The calibration curves for aflatoxin B1 and M1 showed good linearity (r2  > 0.9921) within linear ranges. The limit of detection (S/N = 3) were determined to be 0.049 and 0.023 µg/kg for aflatoxin M1 and B1, respectively. In addition, the good spiked recoveries were obtained ranging from 88.24 to 105.35%. The results demonstrated that the proposed method had significant advantages including simple, inexpensive, rapid, and accurate, which considered as a suitable method for the trace analysis of aflatoxins.


Assuntos
Aflatoxina B1/análise , Aflatoxina M1/análise , Leite/química , Extração em Fase Sólida , Ziziphus/química , Animais , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem , Fatores de Tempo
7.
Nano Lett ; 16(1): 512-8, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26619096

RESUMO

Solid oxide fuel cells (SOFCs) have potential to be the cleanest and most efficient electrochemical energy conversion devices with excellent fuel flexibility. To make SOFC systems more durable and economically competitive, however, the operation temperature must be significantly reduced, which depends sensitively on the development of highly active electrocatalysts for oxygen reduction reaction (ORR) at low temperatures. Here we report a novel silver nanoparticle-decorated perovskite oxide, prepared via a facile exsolution process from a Sr0.95Ag0.05Nb0.1Co0.9O3-δ (SANC) perovskite precursor, as a highly active and robust ORR electrocatalyst for low-temperature SOFCs. The exsolved Sr0.95Ag0.05Nb0.1Co0.9O3-δ (denoted as e-SANC) electrode is very active for ORR, achieving a very low area specific resistance (∼0.214 Ω cm(2) at 500 °C). An anode-supported cell with the new heterostructured cathode demonstrates very high peak power density (1116 mW cm(-2) at 500 °C) and stable operation for 140 h at a current density of 625 mA cm(-2). The superior ORR activity and stability are attributed to the fast oxygen surface exchange kinetics and the firm adhesion of the Ag nanoparticles to the Sr0.95Nb0.1Co0.9O3-δ (SNC0.95) support. Moreover, the e-SANC cathode displays improved tolerance to CO2. These unique features make the new heterostructured material a highly promising cathode for low-temperature SOFCs.

8.
Zhongguo Yi Liao Qi Xie Za Zhi ; 41(1): 29-32, 2017 Jan.
Artigo em Zh | MEDLINE | ID: mdl-29792656

RESUMO

Objective: In order to overcome the problems that bone rongeur and Kirschner forcep's less function and easy damage, trivial and inefficient, bulky volume, bone and needle broken edge is not neat, needle tail easy spatter wounding and other defects, integrated "U" shaped cutting edge rongeurs of pruning finger-toe and bending-truncating pin is desigened. Methods: Pruning-truncating rongeurs set the trimming, bending and shearing, straight and twisting, loading and unloading, filing and stripping, string devices, aintenance functions and other functions in one, compare with bone rongeurs in clinical application. Results: Pruning-truncating rongeurs are molding once, manipulation convenient, light and safe, anti damage and maintenance free, cost-effective. Conclusion: Pruning-truncating rongeurs are highly integrated and portable anti-lost, preparation instrument swift, man-machine coordination, sharp instrument injury prevention, to improve the operation efficiency.


Assuntos
Instrumentos Cirúrgicos
9.
Angew Chem Int Ed Engl ; 55(31): 8988-93, 2016 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-27294808

RESUMO

The Aurivillius oxide Bi2 Sr2 Nb2 MnO12-δ (BSNM) was used as a cobalt-free cathode for intermediate-temperature solid oxide fuel cells (IT-SOFCs). To the best of our knowledge, the BSNM oxide is the only alkaline-earth-containing cathode material with complete CO2 tolerance that has been reported thus far. BSNM not only shows favorable activity in the oxygen reduction reaction (ORR) at intermediate temperatures but also exhibits a low thermal expansion coefficient, excellent structural stability, and good chemical compatibility with the electrolyte. These features highlight the potential of the new BSNM material as a highly promising cathode material for IT-SOFCs.

10.
Zhongguo Yi Liao Qi Xie Za Zhi ; 40(2): 111-4, 2016 Mar.
Artigo em Zh | MEDLINE | ID: mdl-29763226

RESUMO

Objective: In order to overcome the problems that the ordinary sounder's volume is bulky, has less function, is inconvenient to carry, its adaptation is weak, easy faling damage or occurrence of sharp instrument injury and other defects, the multifunctional portable universal safety type bone hole probe pen is developed. Methods: This pen set detection, loading and unloading, twisting and winding, straight, guide and maintenance functions in one. Take reference to contrast with ordinary sounder after surgery, experiment and teaching application. Results: This pen is a multipurpose, safe and universal, damage-resistant and portable, high cost-effective. Conclusions: This pen is easy to carry and store, the apparatus preparation is simple and quick, it can free instrument box, prevent of sharp injuries, improve the operating efficiency. Its adaptation is high, it is suitable both in peacetime and in wartime.


Assuntos
Osso e Ossos/lesões , Humanos , Segurança do Paciente
11.
Zhongguo Yi Liao Qi Xie Za Zhi ; 40(6): 421-4, 2016 Nov.
Artigo em Zh | MEDLINE | ID: mdl-29792603

RESUMO

Objective: In order to overcome the disadvantages of the common single handle cold scalpel such as cicatrix cutting inefficient, large amount of skin losses, margin concave and convex, cutting marks poor healing, a safe and general type of convenient instalation and instantly removable"A"shaped scalpel handle was developed. Methods: For the convenience of the single hand independent, cicatrix cutting smoothly and conveniently, man-machine design"A"shaped scalpel handle and application. Results: The"A"shaped scalpel handle has good precision and controllability. When loading or unloading the blades, it's convenient, efficient and safe, free choice of direction. Conclusion: The"A"shaped scalpel handle with cicatrix cutting single hand is independent, universal for al blades, can conveniently instal and instantly remove, is portable and easy to storage, has wide range of applications. The prevention of sharp instrument injuries reduces the occupation injury risks and improves operation efficiency


Assuntos
Instrumentos Cirúrgicos , Cicatriz , Humanos , Masculino
12.
Angew Chem Int Ed Engl ; 54(13): 3897-901, 2015 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-25653050

RESUMO

The perovskite SrNb0.1 Co0.7 Fe0.2 O3-δ (SNCF) is a promising OER electrocatalyst for the oxygen evolution reaction (OER), with remarkable activity and stability in alkaline solutions. This catalyst exhibits a higher intrinsic OER activity, a smaller Tafel slope and better stability than the state-of-the-art precious-metal IrO2 catalyst and the well-known BSCF perovskite. The mass activity and stability are further improved by ball milling. Several factors including the optimized eg orbital filling, good ionic and charge transfer abilities, as well as high OH(-) adsorption and O2 desorption capabilities possibly contribute to the excellent OER activity.

13.
Neurobiol Dis ; 68: 57-65, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24769004

RESUMO

Although sleep complaints are very common among pregnant women, the potential adverse effects of sleep disturbance on the offspring are not well studied. Growing evidence suggests that maternal stress can induce an inflammatory environment on the fetal development. But people are not sure about the consequences of prenatal stress such as the inflammatory responses induced by maternal sleep deprivation (MSD). In the present study, we investigated the effects of MSD on long-term behavioral and cognitive consequences in offspring and its underlying inflammatory response pathway. The pregnant Wistar rats received prolonged sleep deprivation (72h) on gestational day (GD) 4, 9, and 18, respectively. The post-natal day (PND) 21 offspring showed impaired hippocampus-dependent spatial learning and memory in the Morris Water Maze task and anhedonia in sucrose preference experiment. Quantification of BrdU(+) and DCX(+) cells revealed a significant decrease in hippocampus neurogenesis in prepuberty offspring, especially for the late MSD (GD 18) group. Real-time RT-PCR showed that after MSD, the expression of pro-inflammatory cytokines (IL-1ß, IL-6 and TNFα) increased in the hippocampus of offspring on PND 1, 7, 14 and 21, whereas anti-inflammatory cytokine IL-10 reduced at the same time. Immunofluorescence found that the cells of activated microglia were higher in the brains of MSD offspring. Taken together, these results suggested that the MSD-induced inflammatory response is an important factor for neurogenesis impairment and neurobehavioral outcomes in prepuberty offspring.


Assuntos
Hipocampo/fisiopatologia , Interleucina-10/metabolismo , Neurogênese/fisiologia , Efeitos Tardios da Exposição Pré-Natal/patologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Privação do Sono/complicações , Fatores Etários , Animais , Peso Corporal/fisiologia , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/patologia , Proteínas do Domínio Duplacortina , Proteína Duplacortina , Feminino , Preferências Alimentares/fisiologia , Idade Gestacional , Masculino , Aprendizagem em Labirinto/fisiologia , Proteínas Associadas aos Microtúbulos/metabolismo , Neuropeptídeos/metabolismo , Gravidez , Ratos , Ratos Wistar , Razão de Masculinidade , Sacarose/administração & dosagem
14.
Environ Sci Technol ; 48(12): 7122-7, 2014 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-24856957

RESUMO

In this study, we propose and experimentally verified that methane and formic acid mixed fuel can be employed to sustain solid oxide fuel cells (SOFCs) to deliver high power outputs at intermediate temperatures and simultaneously reduce the coke formation over the anode catalyst. In this SOFC system, methane itself was one part of the fuel, but it also played as the carrier gas to deliver the formic acid to reach the anode chamber. On the other hand, the products from the thermal decomposition of formic acid helped to reduce the carbon deposition from methane cracking. In order to clarify the reaction pathways for carbon formation and elimination occurring in the anode chamber during the SOFC operation, O2-TPO and SEM analysis were carried out together with the theoretical calculation. Electrochemical tests demonstrated that stable and high power output at an intermediate temperature range was well-maintained with a peak power density of 1061 mW cm(-2) at 750 °C. With the synergic functions provided by the mixed fuel, the SOFC was running for 3 days without any sign of cell performance decay. In sharp contrast, fuelled by pure methane and tested at similar conditions, the SOFC immediately failed after running for only 30 min due to significant carbon deposition. This work opens a new way for SOFC to conquer the annoying problem of carbon deposition just by properly selecting the fuel components to realize their synergic effects.


Assuntos
Carbono/análise , Formiatos/química , Metano/química , Óxidos/química , Temperatura , Catálise , Coque/análise , Eletricidade , Eletrodos , Microscopia Eletrônica de Varredura , Oxigênio/química , Fatores de Tempo
15.
R Soc Open Sci ; 11(2): 231616, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38356873

RESUMO

Dormancy release pattern, sprout growth and later reproduction were studied among various tuber sizes of Cyperus esculentus to determine effective methods to release dormancy and further to select suitable tuber size of this species in production. The results showed that medium tubers performed better during sprouting than large and small tubers under all pre-sprouting treatments. Pre-sprouting treatments at 25°C, 35°C, RT (room temperature) and -2°C were effective in relieving dormancy in medium tubers. Tiller number from medium tubers were significantly higher under 25°C, RT and 45°C than under 35°C and -2°C. Shoot and root mass from medium tubers were significantly higher under the 25°C, 35°C and RT than under other treatments. Tiller and tuber numbers both decreased with decreasing tuber size, as did tuber yield after three months of growth. Furthermore, leftover mass decreased with decreasing tuber mass and remained unchanged at sprouting and maturity periods. A significantly negative allometric correlation was found between plant mass and tuber mass from small tubers. However, a significantly positive allometric correlation was found between tuber size and tuber number from large tubers. In conclusion, medium tubers had a competitive advantage in sprouting, growth and reproduction.

16.
Int J Biol Macromol ; 263(Pt 2): 129939, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38423909

RESUMO

Polysaccharides are biologically essential macromolecules, widely exist in plants, which are used in food, medicine, bioactives' encapsulation, targeted delivery and other fields. Suitable extraction technology can not only improve the yield, but also regulate the physicochemical, improve the functional property, and is the basis for the research and application of polysaccharide. High pressure (HP) extraction (HPE) induces the breakage of raw material cells and tissues through rapid changes in pressure, increases extraction yield, reduces extraction time, and modifies structure of polysaccharides. However, thus far, literature review on the mechanism of extraction, improved yield and modified structure of HPE polysaccharide is lacking. Therefore, the present work reviews the mechanism of HPE polysaccharide, increasing extraction yield, regulating physicochemical and functional properties, modifying structure and improving activity. This review contributes to a full understanding of the HPE or development of polysaccharide production and modification methods and promotes the application of HP technology in polysaccharide production.


Assuntos
Medicina , Polissacarídeos , Polissacarídeos/farmacologia , Polissacarídeos/química , Extratos Vegetais/química , Substâncias Macromoleculares , Antioxidantes/química
17.
Theor Appl Genet ; 126(10): 2499-509, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23836385

RESUMO

Increasing seed oil content has become one of the most important breeding criteria in rapeseed (Brassica napus). However, oil content is a complex quantitative trait. QTL mapping in a double haploid population (SG population) emerging from a cross between a German (Sollux) and Chinese (Gaoyou) cultivars revealed one QTL for oil content on linkage group A1 (OilA1), which was mapped to a 17 cM genetic interval. To further validate and characterize the OilA1, we constructed a high-resolution map using B. rapa sequence resources and developed a set of near-isogenic lines (NILs) by employing a DH line SG-DH267 as donor and Chinese parent Gaoyou as recurrent background. The results showed highly conserved synteny order between B. rapa and B. napus within the linkage group A1 and revealed a possible centromere region between two markers ZAASA1-38 and NTP3 (2.5 cM). OilA1 was firstly validated by 250 BC5F2 plants and was confirmed in a 10.6 cM interval between the markers ZAASA1-47 and ZAASA1-77. Further substitution mapping was conducted by using two generations of QTL-NILs, 283 lines from eight BC5F3:4 families and 428 plants from six BC5F4 sub-NILs and thus narrowed the OilA1 interval to 6.9 cM and 4.3 cM (1.4 Mb), respectively. Field investigations with two replications using homozygous BC5F3:4 sister sub-NILs indicated that NILs, which carry a Sollux chromosome segment across the target region showed significant higher oil content (1.26 %, p < 0.001) than their sister NILs containing Gaoyou chromosome. The OilA1 locus is of particular interest for breeding purpose in China because 80 % of Chinese cultivars do not carry this desirable allele.


Assuntos
Brassica napus/genética , Genes de Plantas/genética , Óleos de Plantas/metabolismo , Locos de Características Quantitativas/genética , Alelos , Cruzamentos Genéticos , Marcadores Genéticos , Genótipo , Endogamia , Mapeamento Físico do Cromossomo , Reprodutibilidade dos Testes
18.
Artigo em Inglês | MEDLINE | ID: mdl-37067968

RESUMO

Joint entity and relation extraction is an important task in natural language processing, which aims to extract all relational triples mentioned in a given sentence. In essence, the relational triples mentioned in a sentence are in the form of a set, which has no intrinsic order between elements and exhibits the permutation invariant feature. However, previous seq2seq-based models require sorting the set of relational triples into a sequence beforehand with some heuristic global rules, which destroys the natural set structure. In order to break this bottleneck, we treat joint entity and relation extraction as a direct set prediction problem, so that the extraction model is not burdened with predicting the order of multiple triples. To solve this set prediction problem, we propose networks featured by transformers with non-autoregressive parallel decoding. In contrast to autoregressive approaches that generate triples one by one in a specific order, the proposed networks are able to directly output the final set of relational triples in one shot. Furthermore, we also design a set-based loss that forces unique predictions through bipartite matching. Compared with cross-entropy loss that highly penalizes small shifts in triple order, the proposed bipartite matching loss is invariant to any permutation of predictions; thus, it can provide the proposed networks with a more accurate training signal by ignoring triple order and focusing on relation types and entities. Various experiments on two benchmark datasets demonstrate that our proposed model significantly outperforms the current state-of-the-art (SoTA) models. Training code and trained models are now publicly available at http://github.com/DianboWork/SPN4RE.

19.
Sci Adv ; 9(34): eadh9487, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37624888

RESUMO

Developing technologies based on the concept of methanol electrochemical refinery (e-refinery) is promising for carbon-neutral chemical manufacturing. However, a lack of mechanism understanding and material properties that control the methanol e-refinery catalytic performances hinders the discovery of efficient catalysts. Here, using 18O isotope-labeled catalysts, we find that the oxygen atoms in formate generated during the methanol e-refinery reaction can originate from the catalysts' lattice oxygen and the O-2p-band center levels can serve as an effective descriptor to predict the catalytic performance of the catalysts, namely, the formate production rates and Faradaic efficiencies. Moreover, the identified descriptor is consolidated by additional catalysts and theoretical mechanisms from density functional theory. This work provides direct experimental evidence of lattice oxygen participation and offers an efficient design principle for the methanol e-refinery reaction to formate, which may open up new research directions in understanding and designing electrified conversions of small molecules.

20.
Nat Commun ; 14(1): 2467, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37117165

RESUMO

Understanding and mastering the structural evolution of water oxidation electrocatalysts lays the foundation to finetune their catalytic activity. Herein, we demonstrate that surface reconstruction of spinel oxides originates from the metal-oxygen covalency polarity in the MT-O-MO backbone. A stronger MO-O covalency relative to MT-O covalency is found beneficial for a more thorough reconstruction towards oxyhydroxides. The structure-reconstruction relationship allows precise prediction of the reconstruction ability of spinel pre-catalysts, based on which the reconstruction degree towards the in situ generated oxyhydroxides can be controlled. The investigations of oxyhydroxides generated from spinel pre-catalysts with the same reconstruction ability provide guidelines to navigate the cation selection in spinel pre-catalysts design. This work reveals the fundamentals for manipulating the surface reconstruction of spinel pre-catalysts for water oxidation.

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